Application Dossier for Nomination
to the Global Geoparks Network

A Story of Gifts from Deep Inside the Earth Connecting Land and People Together

Mt. Apoi GeoparkJAPAN

http://www.apoi-geopark.jp/

Mt.Apoi Geopark, JapanINDEX
A. Identification of the Area
A-1.

Name of the Proposed Geopark

01

A-2.

Location of the Proposed Geopark
Surface area, physical and human geography characteristics of the
proposed Geopark
Organization in charge and management structure of the proposed
Geopark
Application Contact Person

01

A-3.
A-4.
A-5.

02
06
07

B. Geological Heritage
B-1.

General geological description of the proposed Geopark

08

B-2.

Listing and description of geological sites within the proposed Geopark
Detailed on the interest of these sites in terms of their international,
national, regional or local value
Listing and description of other sites of natural, cultural and intangible
heritage interest and how they are related to the geological sites and how
they are integrated into the proposed Geopark

15

B-3.
B-4.

18
20

C. Geoconservation
C-1.
C-2.
C-3.

Current or potential pressure on the proposed Geopark
Current status in terms of protection of geological sites within the
proposed Geopark
Data on the management and maintenance of all heritage sites

27
27
28

D. Economic Activity & Business Plan
D-1.

Economic activity in the proposed Geopark

29

D-2.

Existing and planned facilities for the proposed Geopark

30

D-3.

Analysis of geotourism potential of the proposed Geopark

31

D-4.

Overview and policies for the sustainable development
Policies for, and examples of, community empowerment in the proposed
Geopark
Policies for, and examples of, public and stakeholder awareness in the
proposed Geopark

32

D-5.
D-6.

E. Interest and arguments for joining the GGN

36
38
39

Appendix
Cited Literature and References

41

1

List of Horoman Peridotite Publications

42

2

Mt. Apoi Geopark Geosite List

47

Mt.Apoi Geopark, Japan

A. Identification of the Area
A-1. Name of the Proposed Geopark
The name of the proposed area is Mt. Apoi Geopark. Mt. Apoi is 810 meters high and located in
Hokkaido, which is the northernmost island of the Japanese Archipelago.
The name Mt. Apoi derives from the language of the indigenous Ainu people of Hokkaido; it is acorruption of the term Ape-o-i-nupuri (meaning “the mountain where a big fire was made”), which
originated in a legend that tells the story of Ainu people making a fire on top of the mountain andpraying to a kamuy (god) for success in hunting deer (a vital part of the Ainu diet).
The most distinctive feature of Mt. Apoi Geopark is the mountain’s peridotites, which derive fromthe earth’s mantle. They are visible above ground because part of the upper mantle containing them,which is further beneath the crust, was pushed onto the earth’s surface by a collision of crustal plates.
These rocks form part of Mt. Apoi as a complex. Naturally man has never set foot on the mantle
because it is located deep under the earth’s surface. However, Mt. Apoi Geopark provides visitors witha window into the interior of the earth, allowing them to understand global-scale dynamic movements
underneath the earth. These movements have produced unique and valuable colonies of alpine flora on
Mt. Apoi that fascinate climbers from across Japan. The mountain also supports the daily lives of local
residents.
The Mt. Apoi Geopark Promotion Council in the town of Samani
hereby submits this application for the area to become a member of
the Global Geoparks Network (GGN) as a globally unique place thatprovides insight into the depths of the earth. The application is basedon the theme of narratives regarding our planet’s constitution, nature,and people connected by gifts from deep inside the earth (see B-2).
Fig. A-1 Location of Mt. Apoi
Geopark

A-2. Location of the Proposed Geopark
Mt. Apoi Geopark is located near the southern tip of
Hokkaido, which is the northernmost island of the JapaneseArchipelago (Fig. A-1). Hokkaido is the second largest of theJapanese Archipelago’s many islands. This northern region isa leading domestic tourist destination and is home to the Toya
Caldera and Usu Volcano Global Geopark, whose main theme
is coexistence between people and the ever-changing earth.
Hokkaido is often likened to a ray fish due to its shape. Its
backbone is the Hidaka Mountains, which have 1,500- to
2,000-meter peaks running 150 km from north to south. Mt.
Apoi Geopark is located at the southwestern end of this range
in the administrative district of Samani Town (Fig. A-2).

Fig. A-2 Mt. Apoi Geopark area

Geographic coordinates of the Mt.Apoi Geopark area
Samani Town office

Eastern end

Western end

Southern end

Northern end

Longitude142° 56' 02" E

143° 12' 11" E

142° 51' 49" E

143° 04' 04" E

143° 07' 01" E

Latitude42° 07' 40" N

42° 06' 15" N

42° 08' 11" N

42° 03' 39" N

42° 15' 37" N

Altitude0m - 1365m-1-

Mt.Apoi Geopark, Japan

A-3. Surface area, physical and human geography characteristics of the
proposed Geopark
A-3-1. Area of the Proposed Geopark
Mt. Apoi Geopark has a total area of 364.3 km2, extending 20.6 km from north to south and 20.2 km
from east to west, and has a Pacific coastline of 24.2 km. The area around Mt. Apoi is part (5,630 ha)of Hidaka-sanmyaku Erimo Quasi-National Park, the largest park of its kind in Japan (Fig. A-2).
A-3-2. Geographical Setting of the Proposed Geopark
The Hidaka Mountains formed when the North American Plate was pushed up onto the Eurasian Plate
due to a collision between the two. As a result, the area to the west of the mountains (known as the
Hidaka region), which was pushed by the overlying plate, is mostly hilly terrain and middle-relief
mountains, with settlements concentrated in the coastal area and river basins (Fig. A-3).
About 92% of Mt. Apoi Geopark is forestland. The Apoi Mountains (Mt. Apoi: 810 m; Mt.
Pinneshiri: 958 m) – a branch of the Hidaka Mountains – run from north to south in the eastern part of
the Geopark. Despite being under 1,000 meters high, these peaks serve as local landmarks. Meanwhile,
hilly terrain consisting of Cretaceous Period formations stretches over the western part of the Geopark,with settlements located along the coastline. The coast is characterized by a number of large intrusiverock monoliths, creating a beautiful contrast with the Apoi Mountains.

New Chitose Airport
Tokachi-Obihiro Airport
Hidaka Mountains
Hidaka region

Mt. Apoi Geopark

Fig. A-3 Locations of the Hidaka Mountains and Mt. Apoi Geopark
Pacific Ocean

A-3-3. Access(1) Hokkaido
Access to Hokkaido is generally by air. The most convenient route from outside Japan involves flying
to Hokkaido’s New Chitose Airport via Narita, Tokyo or Kansai International Airport on Japan’s mainisland of Honshu, but direct flights to New Chitose Airport also run from East Asia and Southeast Asia.
(2) Mt. Apoi Geopark
Train, bus and rental-car services are available from New Chitose Airport to Mt. Apoi Geopark. The
train journey involves transfers and takes about 3.5 hours, while the bus or rental-car journey takes just
3 hours.
Railway and road travelers alike have opportunities to enjoy the beautiful landscapes of Hokkaido
en route. The vast Yufutsu wilderness stretching to the south of New Chitose Airport consists of
volcanic ash ground formed by eruptions of Shikotsu Volcano, Mt. Tarumae and other volcanoes, andis home to the Bibi River, Lake Utonai, Benten Marsh and other marshes. Lake Utonai is a fresh-waterlagoon with an area of only about 2 km2, but serves as an important stopover for waterfowl such as
white-fronted geese and swans, and is a wetland site designated under the Ramsar Convention (1991).
After passing the Yufutsu wilderness, travelers head eastward along the coast to the west of the-2-

Mt.Apoi Geopark, Japan

Hidaka Mountains. Terraces extend along the coast and the surrounding area is dotted with farms
where thoroughbred racehorses are raised. Farther along, the ridge of the Hidaka Mountains in the
distance on the left gradually comes closer and meets with the Pacific Ocean at Mt. Apoi. Therefore,
the railway ends at Mt. Apoi.
A-3-4. Social Economy(1) Population
Samani Town, where Mt. Apoi Geopark is located, has a population of 5,114. This is almost half thepeak figure of 10,163 recorded in 1955 (population census data, 1955 – 2010). The depopulation rateis particularly high for the most recent decade at approximately 1.8 percent a year (population census
data, 2000 – 2010).
Although provincial depopulation affects the whole of Japan, it is pronounced in Samani due largely
to a lack of people returning to the town because of its fragile industrial infrastructure.
(2) Economic Activity
The main local industries are fishing, mining, and manufacturing. While the annual production valueof the latter two industries is 10,279 million yen (Census of Manufacturers, 2010), that of the fishingindustry is only 2,480 million yen (Catch Statistics, 2011). Despite this disparity, the fishing industry
can be considered to support the local economy in terms of the large number of jobs it creates and its
significant ripple effects on the region’s economic wellbeing. The tourist industry accounts for only asmall part of the local economy, but an average of 100,000 visitors come to the region annually.
A-3-5. Natural environment(1) Landscape
Mt. Apoi Geopark is located at the point where the Hidaka Mountains meet the sea. This flat areaaffords sweeping views of the Apoi Mountains (Fig. A-4) to the east and the main ridgeline of thesouthern part of the Hidaka Mountains to the north. In addition to the main ridgeline, the Apoi
Mountains also form another sharp ridgeline unique to their main range (the Hidaka Mountains),
creating a beautiful form against the sky. Meanwhile, the relatively monotonous coastline thatstretches to the western part of the region drastically changes in Mt. Apoi Geopark with extensive sea
cliffs to the south of Mt. Apoi. This scenic spot is known as Hidaka Yabakei.
The region is characterized by a combination of mountainous and coastal landscapes. This isexemplified by the view of rocky monoliths formed by coastal erosion and Mt. Apoi behind them (Fig.
A-5) as seen from high ground in the western part of the region. Typical local scenes along the coast
include fishing ports of varying sizes, traditional fishing villages, fishing boats on the sea and dryingof kelp (a local specialty) (Fig. A-6).

Fig. A-4 Mt. Apoi – Mt. Pinneshiri

Fig. A-5 Rocky monoliths along
the coast and Mt. Apoi

Fig. A-6 Family kelp drying(2) Natural Monuments and Scenic Spots
The alpine plant communities found across the summit area of Mt. Apoi have been designated by theJapanese government as a Special Natural Monument of Japan. They consist of ultrabasic plants
endemic to the mountain, such as Hidakaso (Callianthemum miyabeanum), Ezokozorina (Hypochoeris
crepidioides) and Apoikuwagata (Veronica schmidtiana var. yezoalpina form. exigua.), a number ofrare species, and alpine types that grow even at low altitudes on Mt. Apoi (Fig. A-7). The-3-

Mt.Apoi Geopark, Japan

Himechamadaraseseri (Pyrgus malvae) butterfly, whose habitat is Mt. Apoi and the surrounding area
(i.e., the Apoi Mountains and Mt. Horoman), has also been designated as a Natural Monument ofJapan. This is a northern species seen extensively in Eurasia, but in Japan is found only on Mt. Apoi
and the surrounding area (Fig. A-8). The spread of Kitagoyo (P. parviflora var. pentaphylla) trees
across the foot of Mt. Horoman is another Natural Monument of Japan known as the Northern Limit ofHoroman Japanese White Pine’s Habitat. Black woodpeckers and Blakiston’s fish owls living inwoodland areas of Mt. Apoi and the surrounding area as well as Steller’s sea eagles, white-tailed
eagles, bean geese, and white-fronted geese that fly to the region in winter are also Natural
Monuments of Japan (Fig. A-9).
The region’s concentration of Natural Monuments highlights the significance of its naturalenvironment. It is also noteworthy that these rare biotic communities are closely related togeohistorical factors unique to Mt. Apoi and the surrounding area.

Fig. A-7 Hidakaso (Callianthemum
miyabeanum) – an endemic
species native to Mt. Apoi

Fig. A-8 Himechamadaraseseri(Pyrgus malvae) – a Natural
Monument of Japan

Fig. A-9 Steller’s sea eagle – a
Natural Monument of Japan(3) Climate
The region’s climate, which is hemiboreal (Dfb) according to the Köppen classification, is strongly
influenced by the sea. The average yearly temperature is 8.0°C, and the average temperature of thecoldest month (January) is 2.5°C – considerably higher than other regions of Hokkaido. However, thetemperature of even the warmest month (August) is below 20°C at 19.9°C. These characteristics arise
because this sea-facing region is not affected by strong radiative cooling in winter, while dense fog
brought in by winds passing over cold currents mitigates temperature increases in summer (Fig. A-10).
The annual minimum temperature is around 11°C, and the
30°C level has been exceeded only three times in therecorded history of over 50 years. The annual average
number of foggy days is 56, and many of these are in summer.
The annual average number of days with maximum windspeeds of at least 10 meters is 121, which rises to 270 at Cape
Erimo in the eastern part of the region. Annual precipitationis relatively low at around 1,000 mm, but shows a slightincreasing tendency in summer. As the region faces the
Pacific Ocean, the amount of snowfall is small; the average Fig. A-10 Sea fog – a common local
sight in summer
maximum snow depth is just 21 cm.
(4) Ecosystems
The region is largely characterized by relatively limited economic activity and a smooth transition
from a coastal environment to an alpine environment across a compact tract of land. The coast near Mt.
Apoi and its surroundings remain particularly unspoiled, with characteristic continuity between local
marine and terrestrial ecosystems. The region is predominantly covered by trees, with forests ofevergreen coniferous or mixed coniferous and broad-leaved species stretching over Mt. Apoi, Mt.
Horoman and the surrounding areas (Fig. A-11). The forest communities in this region represent oneof the world’s only habitats where Kitagoyo (P. parviflora var. pentaphylla; a cool temperate-zone-4-

Mt.Apoi Geopark, Japan

species) and alpestrine Glehn’s spruce trees grow together. This spectacular natural environment hasbrought Mt. Apoi and the surrounding area, including the coastal zone, designation as part of Hidakasanmyaku Erimo Quasi-National Park.
This region provides habitats for alpine plants and animals, such as the Japanese pika, that arenormally not found in low altitudes, and also represents the eastern limit for numerous temperate-zone
plants (e.g., Stephanandra incise and Quercus serrata). An extraordinary ecosystem characterized by
the coexistence of northern and temperate flora and fauna has consequently formed, making the area abiodiversity hotspot. The presence of alpine plants at low altitudes is attributed to light snowfall andstrong winds in winter, cool summer weather and unique geological conditions. The distribution ofseveral temperate-zone plants in this region defies explanation based on present climatic conditions
alone, and is therefore seen to reflect the ancient connection of land between Hokkaido and thenorthern Honshu region of Japan, which are today separated by the Tsugaru Strait.
Mt. ApoiFig. A-11 Vegetation map of Mt. Apoi and the surrounding area (source: National Survey on the Natural
Environment (Vegetation Survey), Ministry of the Environment). The main local species are deciduous
broad-leaved trees (e.g., Japanese oak), but coniferous trees dominate Mt. Apoi and its surroundings(mostly corresponding to the area of surface peridotite exposure).

A-3-6. History and Culture(1) Historical Background
Hokkaido’s indigenous Ainu people (those who lived in northern
Japan before people of ethnic Japanese decent) carried on the
traditions of the nearly 10,000 year long prehistoric Jomon period(12,000-300BC), and thus subsisted on hunting, fishing, andgathering. The relevant eras are the Epi-Jomon culture period (2ndcentury B.C. – 6th century A.D.), the Satsumon and Okhotsk culture
periods (7th century – 12th century) and the Ainu culture period(13th century onward). Most Hokkaido place names are derived fromthe Ainu language, and oral folklore tells of the region’s geology.
Hokkaido is home to more than 500 known sites previously occupied
by Ainu forts called chashi, and legends of such forts are also
associated with Mt. Apoi Geopark (Fig. A-12).
Everyday aspects of Ainu culture are no longer passed down today
due to the assimilation of Ainu people into Japanese society
following the settlement of wajin (people of ethnic Japanese descent)from the main island of Honshu and elsewhere primarily in the 18th
century. However, oral traditions (such as yukar epic poetry) and

Fig. A-12 Mt. Kannon – thesetting of a chashi legend
Mukkur (mouth harp)

Traditional Ainu danceFig. A-13 Preserved elementsof traditional Ainu culture-5-

Mt.Apoi Geopark, Japanother aspects of the culture have been passed down from generation to generation. Traditional Ainu
dance, which has been preserved in the region, was designated as an Important Intangible Folk
Cultural Property of Japan in 1984 (Fig. A-13).
(2) Culture and Customs
The region is home to numerous shrines dedicated to prayers for safe and bountiful fishing activities
and good harvests. Small-scale festivals have long been held in settlements where these shrines arelocated (Fig. A-14).
The annual summer Apoi Fire Festival features the re-enactment of a legend in which Ainu people
built a fire at the top of the mountain. This major event promotes enjoyment of the short local summer,with floats created by local communities being paraded through the region (Fig. A-15). Events at
which local products are sold are also held in autumn.
In this region of sea and mountains, locals harvest wild edible greens in the mountains in spring andmake izushi from salmon or other fish in winter. Izushi is a traditional preserved food made byfermenting fish with vegetables, rice, other ingredients and lactic acid. The recipe varies from family
to family (Fig. A-16).

Fig. A-14 Annual Sumiyoshi
Shrine Festival

Fig. A-15 Apoi Fire Festival

Fig. A-16 Production of
salmon izushi

A-4. Organization in charge and management structure of the proposed
Geopark
A-4-1. Management Body
Mt. Apoi Geopark is operated by the Mt. Apoi Geopark Promotion Council in Samani, which wasestablished in July 2008 by the Samani municipal government and assembly, economic, industrial, andcitizen councils, and other organizations. The Mayor of Samani serves as its President.
As a rule, a General Committee meeting is held once a year for the discussion and approval ofbudgetary matters and plans. The Executive Committee consists of the President, the Vice-President
and subcommittee chairs, and makes coordinated decisions on business plans discussed by threesubcommittees (the Planning and Finance Subcommittee, the Education and Public AwarenessSubcommittee and the Tourism and Industry Subcommittee). The subcommittees create and formulate
plans in conjunction with the Secretariat (Fig. A-17).
A-4-2. Secretariat Structure
The Secretariat is part of the Samani Town Government’s Commerce, Industry and Tourism
Department, and has staff tasked with the promotion of Mt. Apoi Geopark. As of November 2014, theSecretariat has six staff: one administrator, three clerks, one geological expert (with an MS degree inpetrology) and one curator (botany). The Secretariat also has four clerks who additionally work forindividual subcommittees. In fiscal year 2015, an expert in history will be hired to reinforce
investigation and utilization efforts relating to local historical matters (e.g., Ainu culture).

-6-

Mt.Apoi Geopark, Japan

A-4-3. Academic Support Structure
The Mt. Apoi Geopark Promotion Council in Samani receives academic support from experts on
peridotites and alpine plants – two main features of Mt. Apoi Geopark (Fig. A-18).
Geology
Shoji Arai
Tsuyoshi Toyoshima
Eiichi Takazawa
Takashi Sawaguchi
Kiyoaki Niida
Takehiro Masuzawa
Ken Sato
Masashi Ohara
Yoshimi Takahashi

Faculty of Natural Systems,
Institute of Science andEngineering,
Kanazawa
University
Graduate School of Scienceand Technology, Niigata
University
Graduate School of Scienceand Technology, Niigata
University
Department of Economics,
Faculty of Economics, Toyo
University
GeoLab Mt. Apoi

Biology

Facultyof
Science,
Shizuoka University
Department of Life Scienceand Technology, Faculty ofEngineering,
HokkaiGakuen University
Faculty of Environmental
Earth Science, Hokkaido
University
Researcher, former juniorhigh school teacher

Fig. A-18 Academic support structure(advisors)

Fig. A-17 Organization of the Mt. Apoi Geopark
Promotion Council in Samani

A-4-4. Budget and Finance
The Mt. Apoi Geopark Promotion Council in Samani is funded primarily by subsidies from the
Samani Town Government, tour revenue and income from merchandise sales. Funding is allocated to
the Council’s operation, public awareness enhancement activities (e.g., workshops, campaigns, guidetraining), matters concerning geo tours and other considerations.
Meanwhile, guidebooks, pamphlets, signs, websites and other informational tools are developed by
the Samani Town Government based on plans devised by the Mt. Apoi Geopark Promotion Council in
Samani.
The Hokkaido Government is in charge of local preservation and environmental improvement
efforts in the area designated as part of the quasi-national park.

A-5. Application Contact Person
Mr. Takumi Harada
Mt. Apoi Geopark Promotion Council in Samani Secretariat
Assistant director
Commerce, Industry and Tourism Department, Samani Town Government
Odori 1-chome 21, Samani Town, Samani-gun, Hokkaido 058-8501, Japan
Tel.: +81-146-36-2120 Fax: +81-146-36-2662
E-mail: apoi.geopark@festa.ocn.ne.jp-7-

Mt.Apoi Geopark,

Japan

B.

Geological Heritage

B-1.

General geological description of the proposed Geopark

B-1-1.

Geological position and background

Hokkaido is the northernmost island of Japan, and is located between the Pacific Ocean and the AsianContinent. The Hidaka Mountains in the central axial region of Hokkaido are characterized by
2,000-meter peaks, running from north to south, forming the island’s backbone, and dividing into
eastern and western Hokkaido. As shown in Fig. B-1, Mt. Apoi (altitude: 810.2 m; 42° 06’ 28’’ N, 143°
01’ 31’’ E) lies at the southern end of the
Hidaka Mountains, facing the Pacific
Ocean.
Looking at Hokkaido from the ocean
floor of the Pacific, there are steep
escarpments off of the Kuril Islands andNorthern Honshu. The Kuril Trench(running from Kamchatka to eastern
Hokkaido) intersects with the Japan
Trench (running further southward fromwestern
Hokkaido
to
Honshu).
Geographically speaking, this is the sitewhere the Kuril arc is merging with the Fig. B-1 Topographical map around Hokkaido and Mt. Apoi
Honshu arc.
(courtesy: Google Earth)As shown in Fig. B-2, Hokkaido is located at a triple junction of three major plates covering theearth’s Northern Hemisphere: the Pacific Plate, the North
American Plate, and the Eurasian Plate. This section highlights
the location of Mt. Apoi Geopark in relation to these plates. The
Pacific Plate subducts to the northwest beneath the Japanesearchipelago at the northwestern margin of the Pacific Ocean. The
subduction rate is approximately 10 centimeters a year. As
clearly shown in the map of Fig. B-1, Hokkaido was located at
the boundary between the North American Plate and theEurasian Plate, both of which stayed above the subduction slabof the Pacific Plate, at the beginning stage of the Hidaka
Mountains building.
Figure B-3 (map of the Northern Hemisphere) shows anarrangement of these three major plates on a global scale. The Fig. B-2 Map showing relationship of 3
plates in areas near Hokkaido, at
northern extension of the plate boundary between the North major
the beginning stage of the Hidaka
American and the Eurasian plates can be traced to the Atlantic mountain building (Niida, 1999). Mt. Apoi
Ocean, on the other side of the globe. Here, successive was located at the southwestern marginof the North American Plate, colliding onsubmarine volcanic activity along the axis of the Mid-Atlantic the Eurasian plates.
Ridge creates an oceanic lithosphere (comprising the crust to theuppermost mantle) of the Atlantic Ocean floor. The average spreading rate is 2~3 centimeters a year
on one side, which has continued steadily since the end of the Jurassic Period, when the seafloor
spreading began to form the Atlantic Ocean.
As shown in Figure B-3, the divergent plate boundary of the Mid-Atlantic Ridge continues
northward to the Arctic Ocean near the North Pole. The sense of divergence in plate motion changes
into a convergent boundary, near the North Pole onward. In the area surrounding Hokkaido, the plateboundary between the two plates is located at the eastern margin of the Sea of Japan (thick solid line).
At the present stage, the Eurasian Plate is considered to have begun a new subduction eastward
beneath Hokkaido along the boundary. The other boundary along the central axial zone of Hokkaido-8-

Mt.Apoi Geopark,Japan(thick broken line in Fig. B-3) was there when the Hidaka Mountains started lifting up, 13 million
years ago. Then, the western margin of the North American Plate is thought to have been thrust onto
the Eurasian Plate to the west, resulting in the formation of the mountains.
B-1-2.

Geological Overview

This section outlines the geological characteristics of Mt. Apoi Geopark and the surrounding area. The
Hidaka Main Thrust (HMT) extends along the western foot of the Hidaka Mountains in the central partof Fig. B-4. The eastern and the western areas of the HMT have completely different geologicalfeatures. Metamorphic and plutonic rocks are observed in the Hidaka Metamorphic Belt, covering the
Hidaka Mountains to the east, while the western area is characterized by the Cretaceous fore-arc basin
sedimentary rock and the accretionary complexes that formed on trench slopes from the late
Cretaceous to the Paleogene period.
The HMT can be recognized as a global-scale mobile belt of the Earth. The location corresponds
to the convergent plate boundary shown by the thick broken line over central Hokkaido in Fig. B-3(map of the Northern Hemisphere). Therefore, Mt. Apoi Geopark is a showcase which is composed of
two distinct geological formations that were created in different places of the different plates. Mt.Apoi
Geopark gives an opportunity to experience the outcome of global-scale motion of the Earth forvisitors.

Fig. B-3 Map of the Northern Hemisphere of the Earth,showing the relationship between of the Northern American andEurasian plates. (Niida, 2010). The thick solid line shows thepresent boundary between the Northern American and Eurasianplates. The thick broken line running along the central axial
zone of Hokkaido indicates the plate boundary at the Hidaka
mountains building stage (late Miocene). See Fig. B-2.

Fig. B-4 Simplified geological map of
Mt. Apoi Geopark and the surroundingarea, showing major geological units.
Referred from the Seamless Digital
Geological Map of Japan 1:200,000:
Hokkaido (Geological Survey of Japan,
2003).

(1) Geological features of the Hidaka Mountains and local rocks
The Hidaka Metamorphic Belt extends from the Hidaka Main Thrust (HMT) to the eastern foot of the
Hidaka Mountains as shown in Fig. B-4 (geological map). The Horoman peridotites derived from theupper mantle are exposed on the earth’s surface at the base of the metamorphic belt, and are overlaid
with a sequence of geological formations formed within the deep-seated Earth's crust to the east. These
are granulites and amphibolite (high-grade metamorphic rocks representing the lower crust), biotite
gneiss and biotite schist (representing the middle crust) and schistose hornfels and other hornfels(representing the upper crust). Large masses of gabbro that solidified in basaltic magma chambers in-9-

Mt.Apoi Geopark,Japanthe lower crust are exposed on thewestern side of the Hidaka Mountains,and diorite and granite that formed inmagma chambers in the shallow crust
are exposed from the eastern side to thefoot of the mountain range. The
east-west geological cross-section of the
Hidaka Mountains is shown in Figure
B-5, indicating the most representative
metamorphic and plutonic rock types inthe Hidaka Mountains, as well as
geological structures dipping eastward.
This section highlights two valuablerock specimens collected from the Fig. B-5 Geological cross-section of the Hidaka Mountains
Hidaka Mountains. The first is (Niida, 1997). HMT: Hidaka Main Thrust. This profile shows asequence of the most representative metamorphic
granulites, which is a high-grade geologicaland plutonic rock types, which are typically observed in E-W
metamorphic rock representing the traverse of the Hidaka mountain range. All the geological piles
lowermost crust (Fig. B-6). Granulites are dipping eastward.
are primarily composed of garnet,
orthopyroxene, cordierite and plagioclase, and the estimated equilibrium temperature and pressure
based on geothermobarometry are T = 800°C and P = 7.5 kbar (Osanai, 1985). The other is sillimanite
tonalite (Fig. B-7), which was crystallized from tonalitic magmas injected into biotite gneiss in the
middle crust, containing large crystals of sillimanite.
Extensive research has been conducted to determine the age of the metamorphic and the igneousrocks by using radioactive isotopes. The Hidaka Metamorphic Belt is known as an extremely young
formation based on the age determination indicating between 55 and 17 million years ago (from early
Paleogene to middle Miocene) (The Geological Society of Japan, 2010).

Fig. B-6 Granulite from the upper Horobetsu River,composed of garnet, orthopyroxene, cordierite andplagioclase. This represents a high ‐ grade
metamorphic rock from the lowermost crust.

Fig. B-7 Sillimanite tonalite from the beach at
Chipira, containing columnar megacrysts ofsillimanite. This represents a typical rock forming
the middle crust of an active island arcs.

The temperature-pressure chart of Fig. B-8 plots the estimated equilibrium temperature andpressure for typical metamorphic rocks, such as granulites, amphibolite, biotite gneiss, schist andhornfels, obtained from the Hidaka Mountains (Osanai, 1985). The thick broken line shows ageothermal gradient (i.e., the rate of temperature increase with depth) during metamorphism within the
Earth's crust. The highest geothermal gradient of metamorphic rock in the Hidaka Mountains isapproximately 34°C/km as clearly shown in Fig. B-8. This is identical to that of the undergroundtemperature gradient beneath the central axial ranges of an island arc with ongoing volcanic activity
such as the Japanese island arc. Geothermal gradients of around 30°C/km are not as high as thoseobserved in mid-ocean ridges, but are substantially higher than continental gradients (approx.
10°C/km) and oceanic island gradients (approx. 15°C/km).
The Hidaka Mountains are made up of geological units formed at the deeper interior of an island
arc lithosphere. They are scientifically and educationally significant because they provide a visual- 10 -

Mt.Apoi Geopark,Japan

representation of deep-seated lithospheric geology of avery active island arc. In the Hidaka Arc as shown in Fig.
B-8, granulites and amphibolite in the lowermost crust
partially melted when the underground temperature
exceeded approximately 850°C, which is a melting point
for felsic tonalite magma. In the Japanese archipelago andother tectonically active island arcs, metamorphic rockbelow 25 kilometers underground is heated totemperatures above the melting curve, causing melt
generation. Here we can consider melting events
generating in an active lower crust of an arc such as Japan.
In the Hidaka Mountains, regularly stratified
geological formations are well preserved from the upper
mantle to the shallow crust, where these metamorphic andigneous rocks formed. As a result, the geological eventof magma generation beneath the island arc is possibly
explained as shown in a reconstruction model of the
Hidaka Mountains (Fig. B-9). In the Hidaka Mountains,
the representative types of metamorphic and igneousrocks can be observed in outcrops on the earth’s
surface, providing outstanding opportunities for people
to understand the depths of an island arc lithosphere.

Fig. B-8 Temperature-pressure chart formetamorphic rocks from the Hidaka
Mountains (Niida, 1999), showing a highgeothermal gradient (approximately 34°C/
km).

(2) Geology of the western mountains foot to thecoastal areas
The sedimentary rocks, observed in the areas from thefoot of the Hidaka Mountains west of the Hidaka Main
Fig. B-9 Reconstruction model for generations
Thrust (HMT) to the coastal areas, are originated fromof the Hidaka metamorphic and igneous rocks(Niida, 1999), showing a spatial distribution of
the Cretaceous arc-trench systems (i.e., those in the
representative rock types. This corresponds toCretaceous fore-arc basin area, and the late Cretaceousthose in the geological cross-section (Fig. B-5).
to Paleogene accretionary complex area). This geology
differs significantly from that of the Hidaka Metamorphic Belt, which includes metamorphic andplutonic rocks. The ages of the rocks are also different (The Geological Society of Japan, 2010).
Accordingly, it is stressed that Mt. Apoi Geopark is a showcase of a level of geodiversity that clearly
represents a typical arc-trench system.
(a) Cretaceous system (fore-arc basin area)
As shown in the geological map (Fig. B-4), sedimentary rocks(e.g., sandstone, mudstone, and their alternations) thatoriginated in the Cretaceous fore-arc basin are distributed in
the coastal area from Urakawa Town to Samani Town aroundthe lower streams of the Horobetsu and the Samani rivers. The
Cretaceous system in this region often corresponds to the Yezo
Group (mostly to the Middle Yezo Group distributed along thecentral axial part of Hokkaido). In part of the region (i.e., thatin the northwestern area of the figure), the Lower Yezo Group Fig. B-10 Alternating sandstone andand the Sorachi Group are also distributed on a smaller scale. mudstone layers (Middle Yezo Group)
behind Samani Elementary School.
These areas belong to the southernmost region of the
Sorachi-Yezo Belt in the tectonic division for Cretaceous systems in Hokkaido (The GeologicalSociety of Japan, 2010).
(b) Upper Cretaceous – Paleogene System (accretionary complex area)
The late Cretaceous to Paleogene accretionary complex is distributed in areas across the middle to theupper streams of Horobetsu and Samani rivers in the foot of the Hidaka Mountains. The complex was- 11 -

Mt.Apoi Geopark,Japan

formed from the late Cretaceous to the early Paleogene in the accretionary prisms near the trench slopeof the Cretaceous arc-trench system. They consist mostly of sandstone and mudstone, and also include
a large number of blocks of limestone, chert, basaltic pillow lava, and other types of greenstones
everywhere. The rocks vary in size from gigantic (several hundred meters) to small (several
centimeters), and are incorporated within a matrix of sandstone and mudstone. The blocks are exotic,
having older ages from the Triassic to the Jurassic Period, and are considered to have formed inseamounts and oceanic islands on an old oceanic plate (The Geological Society of Japan, 2010). The
Upper Cretaceous to Paleogene systems are also extensively distributed in areas to the northeast of the
Hidaka Metamorphic Belt, and are characterized by transition to hornfels of the Hidaka Metamorphic
Belt in the area shown by the broken line in Fig. B-4.
(c) Neogene System (sedimentary rocks and porphyrite dykes)
Neogene sedimentary rocks and porphyrite dykes are distributed in a limited small area of the coastal
region, which is a residential area of Mt. Apoi Geopark. The
sedimentary rocks are composed primarily of conglomerate,
sandstone, and mudstone, containing shell fossils fromshallow-sea habitats. The porphyrite dykes are observed insandstones and mudstones in the Cretaceous System (thefore-arc basin area), forming a beautiful landscape of oddly
shaped rocks along the Samani coast. As the porphyrite dykes
at Mt. Kannon, Shiogama Tunnel, Rosoku-iwa, Oyako-iwa,
Sobira-iwa, and Cape Enrumu are harder than the surrounding
Fig. B-11
A distinctive coastal
sedimentary host rocks, it forms landscapes of oddly shaped landscape of Mt. Apoi Geopark formedby porphyrite dykes.
masses unaffected by coastal erosions.

(3)

Terraces at the foot of Mt. Apoi (Samani – Horoman coasts)

Fig. B-12 Marine terraces observed in coastal areas from the Samani coast to the Horoman coast at
the southern foot of Mt. Apoi. (Terrace surfaces t1 – t4: after Kanie and Sakai (2002)).

Remarkable terraces can be observed from the Samani
coast to the Horoman coast at the southwestern foot of Mt.
Apoi. Figure B-12 is a view of Mt. Apoi from Cape
Enrumu; flat coastal terraces can be seen at the foot of themountain. The 1:50,000 Geological Map of Horoizumi
shows four planes with the highest at an elevation over
300 meters and the lowest at 20 meters. The presence ofmarine terrace deposits consisting of gravel, sand and clay
has been confirmed in the area (Hunahashi and Igi, 1956).
The coastal terraces located in the area from the Samani
coast to the Horoman coast were also examined in anarticle by Ouchi (1978) on the history of terrace
development in areas near the Hidaka Mountains.

Fig. B-13 Terrace deposits covering the rockat Geosite D-1, Fuyushima’s Ana-iwa. The
yellow arrow points to pebble layers.

The terraces at the foot of the mountain, particularly in one of Samani’s residential areas, areconsidered an important geological feature directly related to the natural environment involving local- 12 -

Mt.Apoi Geopark,Japanhuman and pre-human history. Accordingly, it is necessary to understand aspects of naturalenvironmental transition closely related to local life, such as ground movement caused by an uplift of
the Hidaka Mountains, which is a phenomenon that continued until relatively recently in geologicalterms, sea level changes brought by the cycle of glacial and interglacial periods, and relationships withthe glacial landform of the Hidaka Mountains. Research is scheduled at locations of low terrace
deposits less than 20 meters in height or less, such as at several sea cliffs located in the residential areaof Mt. Apoi Geopark, as shown in Fig. B-13.
B-1-3. Outline of the Horoman Peridotite Complex
Peridotites are distributed along the Hidaka Main Thrust (HMT) of the Hidaka Mountains. The
Horoman peridotite forms the largest complex, and similar masses of the Uenzaru, Pankenushi,
Menashunbetsu, Nikanbetsu complexes are exposed. Small complexes are also known on the earth’s
surface in the middle of Pon-Nikanbetsu River and Abeyaki River. The complexes are bounded byfaults in contact with high-grade metamorphic rocks and overlain by various kinds of metamorphic
and plutonic rocks. All the peridotite complexes in the Hidaka Mountains have layered structures
composed of a variety of peridotite types derived from the upper mantle 60 to 70 km deep from the
Earth's surface (Niida, 2010).
(1) Peridotite types with three different origins
The Horoman peridotites are divided into three peridotite suites (Main Harzburgite-Lherzolite(MHL), Spinel-rich Dunite-Wehrlit (SDW), and Banded Dunite-Harzburgite (BDH)) based on themodal and chemical compositions of the minerals (Takahashi, 1991). These are considered to havebeen derived from the upper-mantle with individually three different origins (Niida, 2010).
(a) MHL suiteThis peridotite suite is composed primarily of harzburgite, spinel lherzolite and plagioclase lherzolite,
which occupies the majority of the Horoman complex (over 90% of the complex). Detailed studies of
their whole-rock chemistry and chemical composition of the constituent minerals, such as olivine,orthopyroxene, clinopyroxene, and spinel, have been carried out. Basaltic melt components gradually
decrease and the degrees of partial melting increase from plagioclase lherzolite through spinellherzolite and to harzburgite. These characteristics in compositional change indicate that the MHL
suite represents peridotites from the solid upper mantle with varying degrees of depletion of basaltic
magma, from fertile undepleted plagioclase lherzolite to extremely depleted residual harzburgite.

Fig. B-14 Four typical peridotite types of the
Horoman complex

Fig. B-15 Pressure-temperature path, showing
ascent history of the Horoman peridotite complex(Ozawa, 2004).

(b) SDW suiteThis peridotite suite is mostly of spinel dunite containing clinopyroxene. Small amounts of wehrlitic
peridotites are also found. It is characterized by a large number of idiomorphic spinel grains, and theperidotites are believed to be cumulates formed by the accumulation of crystals from basaltic magma
based on the characteristic chemical composition of olivine and spinel.
- 13 -

Mt.Apoi Geopark,Japan(c) BDH suiteThis peridotite suite includes harzburgite and olivine pyroxenite, and is characterized by absence ofclinopyroxene. Characteristically, extremely high-Cr spinel and extremely high-Mg olivine arecontained in this peridotite suite. Therefore, the BDH peridotite suite has been explained as cumulate
crystallized from boninite and/or high-Mg andesite magmas.
(2) Magma channels in peridotite
Mafic rocks are found in various sizes in the Horoman peridotite complex. The mafic rock Type I (GBI) and Type II (GB II) have similar rare earth element (REE) contents and isotopic compositions withthose of the Mid-Ocean Ridge Basalt (MORB). Harzburgite in the lower zone of the complex isaccompanied by numerous numbers of dunite dykes. The dunite dykes have also attracted attention as
rocks in magma channels that were formed by an ascent and migration of basaltic magma through theupper mantle peridotites (i.e., rocks crystallized in basaltic magma channels), as shown in the upper
left-photo of Fig. B-14.
(3) Ascent history of the Horoman peridotite complex
The earliest ascent of the MHL suite in the Horoman peridotite complex is examined as the deepest
record on pressure and temperature conditions of the upper mantle. The conditions of the garnet
lherzolite stability field is clearly shown by symplectites with an external shape of euhedral garnet
contained in orthopyroxene porphyroclasts within spinel lherzolite in the lower zone of the complex.
Reddish-purple fine-grained aggregate layers (sp+opx+cpx) containing symplectites are also found inlherzolite, and are considered to be products of decompressional garnet breakdown. Detailed studies
on pressure and temperature of the Horoman peridotites have been carried out, based on thecompositional zoning of Al2O3 in orthopyroxene and clinopyroxene porphyroclasts and thecompositional change of Al (cation) and Wo (mol. %). As shown in Fig. B-15, the ascent history
indicates that the temperatures recorded in the upper zone of the complex are approximately 200°C
higher than those in the lower zone, and that the maximum pressure is at least P = 20 kbar.
Accordingly, the Horoman peridotite complex is considered to have been up-lifted from a depth
greater than 60 km in the upper mantle.
(4) Age of the Horoman peridotites
The formation age of the Horoman peridotites is still an
on-going subject, providing scientifically important
information on the Earth’s history (Niida, 2010). Althoughpreviously published ages are only a part of such endeavors,
the Sm-Nd whole-rock isochron age determined from Light
Rare Earth Element (LREE)-depleted plagioclase lherzoliteand spinel lherzolite is 833±78 Ma (Fig. B-16). Likewise,
the age determined from pyroxenes is 1.15 Ga (1.15 billion
years). These ages are interpreted as those when the
Horoman peridotites remained after major partial melting
in the upper mantle beneath the mid-ocean ridge. Studies
on 187Os/188Os -187Re/188Os whole-rock isochron of
B-16 Nd-Sm isochrons showing age
peridotites and mafic rocks have reported apparent ages of Fig.
of the Horoman peridotites (Yoshikawa
0.91±0.35 Ga (approx. 900 million years) and 1.12±0.24 and Nakamura, 2000).
Ga (approx. 1.1 billion years).
The presence of numerous veins of phlogopite in peridotites in the lower zone of the Horomanperidotite complex has been widely reported, and suggests that a compositional modification took
place during the final stage of up-lifting from the upper mantle. The Rb-Sr isochron age (23.0±1.2 Ma)
and 40Ar-39Ar plateau age (20.6±0.5 Ma) obtained from the veined peridotites indicate an age justbefore the building of the Hidaka Mountains.

- 14 -

Mt.Apoi Geopark,

B-2.

Japan

Listing and description of geological sites within the proposed Geopark

Mt. Apoi Geopark has 35 geosites in 5 areas labeled from A to E (Fig. B-17). The geopark ischaracterized by the closely related themes outlined below. It is hoped that it will eventually lead tothe revitalization of local communities through the establishment of self-sustaining symbiosis between
nature and people.
Main theme:
A Story of Gifts from Deep Inside the Earth Connecting Land and People Together
Theme A: Peridotites – the interior and dynamic movement of the earth
Theme B: Alpine Plants – scarcity and the natural environment
Theme C: Human History – the community of nature and human life

As the individual characteristics of Mt. Apoi Geopark’s 5 areas and 35 geosites have meaningfulconnections with the three themes, visits should ideally be planned with individual objectives in mind
(e.g., research, geological field trips, hiking or scenic tours). This section highlights characteristics andtypical geological sites of each area. For a complete list of geosites, see Appendix 2 (“Mt. Apoi
Geopark Geosite List”).

Fig. B-17

B-2-1.

Mt.Apoi Geopark map

Area A Horomankyo Area : A gorge of peridotites

The peridotite Horomankyo Gorge is located in the lower and middle basins of the Horoman River,which runs from north to south over the central Horoman peridotite complex. It is a well-known site
for peridotite viewing.
Geosite A3.
Japanese White Pine Monument(Typical lherzolite)
This riverside monument marks a habitat of Horoman Japanese white pines – a Natural Monument ofJapan. The area is a type locality for lherzolite, which is a representative peridotite type known for its
significant amounts of pyroxene: thin reddish-purple fine-grainedmineral layers containing spinel-pyroxene symplectites (one toseveral millimeters in diameter) formed during decompressional
garnet breakdown. The lherzolite here provides informations on the
deepest part (approx. 60 – 70 km below the surface) of the mantle
from which the Horoman peridotite derives.
- 15 -

Mt.Apoi Geopark,Japan

Geosite A6.
Horoman-gawa Inari Shrine(Typical plagioclase lherzolite and mafic rocks)
Peridotites containing plagioclase and mafic rocks (Type GB I)
several centimeters thick are observed on the riverbank 200 meters
upstream of Inari Shrine. The plagioclase lherzolite has a highcontent of orthopyroxene (dark brown) and clinopyroxene (darkgreen), and its streaky white parts contain plagioclase. The peridotite
here is considered to be free from partial melting of basaltic magma in the upper mantle, and is typicalof the primitive mantle in terms of chemical composition. The outcrops here have large numbers ofcylindrical potholes often found by rapid streams, creating a distinctive landscape.

B-2-2.

Area B

Mt. Apoi Area : A mountaineering route showcasing the scale of local

peridotites
Mt. Apoi’s terrain is characterized by layered peridotite and gabbroic mafic rocks. The layers are
believed to have formed when mantle peridotite under high temperature conditions flowed or partiallymelted to become magma.
Geosite B5.
Umanose flower fields(Alpine plants and fine views)
The western ridge of Mt. Apoi, known as Umanose (meaning“horse’s back” in Japanese) has an altitude of around 580 meters.
Colorful alpine plants influenced by peridotites are found along thetrail from Umanose to the mountaintop. This location affords
sweeping views of the ridge extending from the top of Mt. Apoi tothe peak of Mt. Pinneshiri to the east, the backbone of the Hidaka
Mountains to the north, and the Pacific Ocean to the south. These
are splendid sights of the Hidaka Mountains and Mt. Apoi, whichwere formed by a collision of tectonic plates.
Geosite B8.
Mt.Apoi to Mt.Yoshida(The upper zone of the Horoman peridotite complex)
This geosite is characterized by a route along the northern ridge
extending from the top of Mt. Apoi to the peak of Mt. Pinneshiri.
The peridotites in this area are part of the uppermost zone of the
Horoman complex, which is around 3,000 meters thick, andperidotites with a conspicuous layering of plagioclase lherzolite and mafic rocks are observed.
B-2-3.

Area C

Samani Coast Area : Landscapes of Cretaceous sedimentary strata

and intrusive rock
The hilly terrain to the west of Mt. Apoi is characterized by Cretaceous fore-arc basin sedimentaryrock (e.g., sandstone and mudstone), while Neogene sedimentary rock and porphyrite form the coastalarea’s unique landscape. Visitors can learn about the geological narratives hidden behind the area’s
different landscapes.
Geosite C1 –C 4.
Cape Enrumu, Oyako-iwa and other oddly shaped rocks(Porphyrite and dykes)
From Cape Enrumu to Shiogama and Fuyuni in the west, porphyrite
dykes running through the surrounding Cretaceous sedimentaryrocks has resulted in the presence of several large rocks along theshore. Magmatic intrusion occurred around 17 million years ago (inMiocene), and the current shapes were formed by coastal erosion.
- 16 -

Mt.Apoi Geopark,Japan

The wave-cut platforms that appear around the rocks at low tide teem with marine life. Magnificent
platy joints are also found at the cliffs behind Cape Enrumu.
Geosite C7.
Old quarry behind Samani Elementary School (Fore-arc basin sediments)
Sandstone and mudstone strata that formed in a Cretaceous fore-arc
basin around 100 million years ago are observed at the old quarry
behind Samani Elementary School. The hilly terrain in the western
half of Mt. Apoi Geopark consists of sedimentary rock from thisperiod and provides contrast with the Apoi Mountains to the east (i.e.,the Hidaka Metamorphic Belt).
B-2-4.

Area D

Hidaka Yabakei Area : A tectonic plate collision site

Hidaka Yabakei is a 6-kilometer stretch of rugged coast with cliffs running from Ana-iwa rock inFuyushima to the mouth of the Horoman River at the southern foot of Mt. Apoi. It is located at the oldboundary between the Eurasian Plate and the North American Plate.
Geosite D1.
Ana-iwa in Fuyushima (Hornfels and marine terrace)
Ana-iwa is a large rock with a hole running through it in Fuyushima
Fishing Port. The place name Fuyushima derives from the Ainu terms
puyo (hole) and shuma (stone). The hole is a sea cave through whichsurf boats traveled at high tide before the fishing port was built there.
The rock is mostly of fine-grained sedimentary rock, but biotite
formed when it was exposed to high temperatures deep in the earth
and then metamorphosed into hornfels. Terrace deposits are found on
top of Ana-iwa, and a small-scale coastal terrace is also located to its
east.
Geosite D2

Fault at the Higashi Fuyushima Tunnel(Serpentinite and metagabbro, and a convergent plate boundary)This geosite is a fault fracture zone by a national highway.
Metagabbro (in the Poroshiri Ophiolite Belt) is in the southwesternpart of the outcrop, and fractured serpentinite can be seen in the upper
part of its northern outcrop. The contact boundary between theserocks forms part of the Hidaka Main Thrust (HMT), and is consideredpart of the convergent plate boundary between the North American Plate and the Eurasian Plate.
Geosite D5.
Geological fold at the Ruranbetsu Tunnel(Hidaka Metamorphic Belt, amphibolite, biotite gneiss and terrace deposits)
In this rocky tract located at arock shed, folded biotite gneiss
and amphibolite of the Hidaka
Metamorphic Belt can beobserved. Amphibolite is ametamorphosed basaltic rock thatoriginated on an old oceanic plate.
Biotitegneissisrockmetamorphosed from terrigenous
clastic sandstone and mudstone. These metamorphosed rocks are considered to have been derived
from an accretionary prism that formed between the latest Cretaceous to the early Paleogene, and thenmetamorphosed. This geosite affords distant views of terrace deposits on the 100-meter-high sea cliffs,
thereby highlighting the area’s ground uplift.
- 17 -

Mt.Apoi Geopark,B-2-5.

Area EJapan

Shintomi Area : Rocks from far-off southern seas

The Shintomi Area is characterized by rocks formed at a Cretaceous accretionary prism, such as
limestone and chert. The accretionary prism is formed from the surface layer of oceanic plate that isaccreted onto a continental plate. Limestone, chert, and basalt derived from southern oceans,thousands of kilometers away, are mixed with terrigenous clastic sandstone and mudstone, forming a
mixture of different rocks known as a mélange. This site is at the southern end of the Idonnappu Belt,
which extends from south to north along the central axial zone of Hokkaido.
Geosite E1.
Old mine of Ono Kogyo Co., Ltd.
(Limestone, an accretionary mélange complex)
This geosite features an outcrop at an old quarry located behind alimestone processing plant. A mélange with blocks of limestone
surrounded by sandstone and mudstone can be observed. Prior
approval is needed to access to this geosite.
Geosite E2.
Lenticular sandstone at the Samani Dam(Sandstone and mudstone, an accretionary mélange complex)
An outcrop of mudstone and sandstone observed along the roadtoward the Samani Dam parking lot. A typical mélange structure canbe seen here, and lenticular sandstone without continuous bedding isobserved in the mudstone bed.
Geosite E3.
Chert in Shintomi(Chert, an accretionary mélange complex)
Translucent gray chert is found along the road near the confluence of
the Samani River and the Menashiesanbetsu River. Chert is denseand hard, and is composed mainly of very fine-grained quartz.

B-3. Details on the interest of these sites in terms of their international,
national, regional or local value
B-3-1.

A Global scale mobile belt

As shown in B-1-1, the geology of Mt. Apoi Geopark and the surrounding area results from global
scale dynamic ground motion.
One of the largest global-scale mobile belts in the world is the Tethyan ophiolite belt, extending
from the European Alps to Greece, Turkey, Iran, Oman, Pakistan, Indus Suture, Andaman, and theGreat Sunda. Here, the Alps mountain ranges were formed by a well-documented collision between
the African and the Eurasian continents, and the collision of the Indian continent and the Asian
continent generated to the uplift of the Himalayas. The Hidaka Mountains in Hokkaido were also
formed in a large mobile belt that divides the Northern Hemisphere almost vertically. The mountainbuilding was a global-scale geological event that took place at a convergent boundary between the
North American and the Eurasian plates. This suggests that the heavy peridotites located in the upper
mantle were up-lifted onto the earth’s surface from the depths of the North American Plate, thereby
forming Mt. Apoi.
B-3-2. Global significance of the Hidaka Mountains
The most attractive geological features of the Hidaka Mountains are summarized in the recent
monograph on "Geology of Japan" volume 1: Hokkaido (edited by the Geological Society of Japan, in- 18 -

Mt.Apoi Geopark,Japan2010). The following four characteristic aspects are mostly based on Chapter 1 Outline of Hokkaido(Niida, 2010) and Chapter 4 Geology and rocks in the Hidaka Collision Zone (Hidaka Mountains)(Osanai et al., 2010)
1. Hidaka Mountains are composed of rocks derived from the deep-seated lithosphere beneath anactive island arc.
2. The rocks are stratified in an original succession generated from the upper mantle to theshallow crust.
3. Such a regular sequence of lithospheric sections observed on the Earth's surface is very rare in theworld.
4. The age is extremely young (55~17 Ma in Cenozoic). The original state of the rocks is wellpreserved in the Hidaka Mountains, having a lot of information about the deep lithospherebeneath island arcs.

B-3-3. Origins of the Horoman Peridotite Complex and its Academic SignificanceThe peridotites on and around Mt. Apoi are scientifically well known around the world as the
Horoman peridotites, and are significant as a typical orogenic lherzolite. The Horoman peridotite
complex extends approximately 8 km from east to west and about 10 km from north to south, covering
the area along the ridgeline from Mt. Apoi to the north of Mt. Pinneshiri, and along the lower andmiddle streams of Horoman River, and the area near Mt. Horoman to the east (Niida, 2010).
The Horoman peridotites are characterized by a wide range of variety in peridotites types,
including dunite, harzburgite, spinel lherzolite and plagioclase lherzolite. Petrologically, they arecomparable to those in the composition range of upper mantle peridotites all over the world. These
diverse types of peridotite are interlayered with a remarkable number of thin layers of pyroxenite andgabbroic mafic rocks. The total thickness of the layered peridotite complex attains around 3,000
meters. As the Horoman peridotites are young and pure, the chemical compositions and the textural
patterns of minerals formed under the high-temperature and high-pressure conditions of the upper
mantle are also well preserved. It is well known that the Horoman peridotite complex is one of themost studied peridotite masses in the world (Appendix 1: List of Horoman Peridotite Publications).
The aims of research on peridotite complexes cover a wide range, and relate to the foundations ofearth science. They include elucidating processes of magma transport in the upper mantle, origins ofcompositional inhomogeneity of the upper mantle, mechanisms behind melt generation and melt
extraction, and solid-melt reactions during melt segregation to the Earth's surface. A further aim is toclarify the formation, modification, and evolution of the initial mantle in the earth’s history. The 4thInternational Orogenic Lherzolite Conference, held in Samani in 2002, was attended by around 100
scientists from 15 countries (Fig. B-18).

Fig. B-18 Memorial of the International Orogenic
Lherzolite Conference held in Samani in 2002.

- 19 -

Fig. B-19 Geological map of the Horomanperidotite complex (Niida, 1984) and major
observation sites.

Mt.Apoi Geopark,Japan

B-4 Listing and description of other sites of natural, cultural and intangible
heritage interest and how they are related to the geological sites and how they
are integrated into the proposed Geopark
As described in B-2, Mt. Apoi Geopark has five areas, each with its own geological andgeomorphological characteristics, and its own natural and cultural heritage elements. The geopark is
associated with a natural environment and local lifestyles closely related to the area’s peridotite andother geological / geomorphological characteristics. In this section, B-4-1 highlights non-geologicalelements by area, and the parts from B-4-2 to B-4-4 detail noteworthy natural and cultural heritage
resources.
B-4-1.

Summary of geosites with non-geological elements(1) Horomankyo Area
The entire gorge is covered in primeval forest, making the landscape even more spectacular. Amongother features, the area of Kitagoyo (P. parviflora var. pentaphylla) trees growing at the northern limitof their habitat across the side of Mt. Horoman is designated as a Natural Monument of Japan (Fig.
B-20). The Kitagoyo trees also form a unique plant community developed under the strong influenceof peridotites. Despite its low altitude, the area near a peridotite research site here provides a habitat toultrabasic plants found in the alpine area on Mt. Apoi. Hydroelectric power facilities (Fig. B-21) built
to leverage the gorge’s landform highlight the relationship between local industry and topography.

Fig. B-20 Japanese white pine habitat in Horoman (designated as a
Natural Monument of Japan; Geosite A3)

Fig. B-21 Horoman RiverPower Station No. 3 – astructure built to leverage
the gorge’s landform(2) Mt.Apoi Area
This area is characterized by internationally recognized alpine plant communities, which developed
under the influence of local ultrabasic peridotite. The flowers along the mountain trail here fascinate
climbers with their beauty. Diverse vegetation along with a variety of ultrabasic plant communities isfound in the area where peridotites are visible on the ground from near Rest Spot No. 4 to themountaintop. The steep terrain makes the land feel higher than it actually is, and the upper part of Mt.
Apoi affords sweeping views of the Pacific Ocean and the Hidaka Mountains (Fig. B-22). However,accelerated environmental change and anthropogenic factors caused the recent rapid decline of plantcommunities, prompting local residents and others to engage in plant protection and regeneration
activities (Fig. B-23). In this area, visitors can learn about the importance of the natural environment
and the link between the unique geological conditions and ecosystems.
(1)

(2)

Fig. B-22 (1) View from the Geosite B4 area; (2) Evidence of theinfluence of peridotites on Mt. Apoi’s alpine plant community- 20 -

Fig. B-23 Alpine plant regeneration
initiative involving locals, researchers
and the government (Geosite B2)

Mt.Apoi Geopark,Japan(3) Samani Coast Area
Intrusive-rock monoliths along the coast to the west of Mt. Apoi create a beautiful contrast with themountain. This unique landscape is the source of numerous legends passed down by indigenous Ainu
people, who have lived in harmony with nature here for hundreds of years. This area encompassing therocky monoliths and Mt. Apoi became a major transit point for thriving maritime trade with Japan’s
main island of Honshu in the latter half of the 18th century, laying the foundations for its development
today. In this area, visitors can learn about local history and lifestyles associated with the landform(Fig. B-24).
(1)

(2)

(3)

Fig. B-24 (1) One of the 33 stone statues of Kannon (the Buddhist deity of mercy), from which the name Mt.
Kannon derives (Geosite C4); (2) Tojuin Temple – one of three temples established in Hokkaido by the Edo
shogunate, and a structure that has witnessed the history of Hokkaido’s development (Geosite C5); and (3) arestored traditional Ainu cise dwelling (Geosite C8)(4) Hidaka Yabakei Area
Precipitous cliffs extend 6 km along the coast of the Pacific Ocean, into which the foot of Mt. Apoi
plunges. This area is believed to be where the Eurasian Plate and the North American Plate once
collided. It was also notoriously difficult to pass, dividing Hokkaido into eastern and western parts.
The cliffs are home to the Samani Mountain Path, which was built around 200 years ago (Fig. B-25).
At the bottom of the cliffs, high-quality Hidaka Kombu kelp (also known as Mitsuishi Kombu or
Laminaria angustata Kjellman) grows on nutrients from the region’s peridotite, and kelp drying
grounds covered with crushed peridotite are extensively found here (Fig. B-26). This area highlights
the history of locals who have overcome the issue of passing through the area and showcases theblessings brought by the landform.
(1)

(2)

Fig. B-25 (1) Samani Mountain Path (built around 200 years ago); (2) a
Wasuke Jizo statue at the Samani Mountain Path east trailhead (bothGeosite D6)

Fig. B-26 Hidaka Kombu
growing on nutrients from theregion’s peridotite

B-4-2. Unique ecosystems nurtured by the local geology(1) Alpine Flora on Mt. Apoi
Mt. Apoi provides habitats to nearly 900 species of vascularplants. The most distinctive feature of its flora is the sheer
variety of alpine plants present despite the mountain’s
altitude of only 810 meters. This is considered to stem fromgeological and climatic factors; the most salient of these is
the unique geology of Mt. Apoi and the surrounding area,
which is mainly composed of ultramafic rocks (peridotites).
Peridotites have a remarkably high content of magnesium
and nickel – elements known to inhibit plant growth. Fig. B-27 Sea fog engulfing Mt. Apoi in
Undeveloped soils in the region also tend to have low summer- 21 -

Mt.Apoi Geopark,Japanfertility due to their oligotrophic and dry nature. In addition, limited snowfall in winter tends to cause
freeze-thaw action within soil in windswept ridge areas. This action affects plants directly andindirectly by damaging roots and destabilizing soil on slopes. The sea fog that often engulfs Mt. Apoi
and the surrounding area also causes lower temperatures during the plant growth season (Fig. B-27).
These multiple factors inhibit forest formation in areas around ridges, thereby leaving more room for
alpine plant growth.
Mt. Apoi provides habitats to numerous endemic ultrabasic plants in areas around the ridge nearits peak, forming a unique floral environment. These include Hidakaso (Callianthemum miyabeanum),
Ezokozorina (Hypochoeris crepidioides) and Apoikuwagata (Veronica schmidtiana var. yezoalpina
form. exigua.). In particular, plants such as Hidakaso (a species from the genus Callianthemum, which
is localized in mid-latitude alpine environments in the Northern Hemisphere) and Ezokozorina (anendemic genus) are of academic significance. There are also four endemic species, one endemic
subspecies, eight endemic variant species, and eight quasi-endemic species among others. Such a
concentration of endemic species (including endemic subspecies, variant species, and others) is seen in
few places worldwide (Fig. B-28). This diversity highlights the role of Mt. Apoi and the surroundingarea as a stage for plant evolution. Relict species with markedly disjunct distribution, such as Kinrobai(Potentilla fruticosa var. rigida) and Ezorurimurasaki (Eritrichium nipponicum var. yezoense), also
grow in the region. The unique environment of Mt. Apoi is seen to have served as a refugium for theseplants, allowing them to survive today. Although the evolution of endemic species and the survival of
disjunct-distribution species are clearly attributable at least in part to the geological and climatic
factors detailed above, the geohistorical fact that the region has not been beneath the sea since the
Tertiary period (approx. 15 million years ago) is also considered important.
It should further be noted that the region is a hotspot for rare wildlife, with over 50 endangered
species living locally.

Fig. B-28

Plants endemic to Mt. Apoi

(2) Fauna on Mt. Apoi
Mt. Apoi and the surrounding area provide habitats to mammals, with brown bears at the top of thefood chain. These include Hokkaido sika deer, Japanese pikas, and Hokkaido sables (Martes zibellina
brachyura). Brown bears – Japan’s largest terrestrial mammal – require vast areas of land and diverse
environments for survival, ranging from seashores and waterfront areas to mountainous regions.
Although these animals are not sighted so often on Mt. Apoi or in the surrounding area, the highfrequency with which footprints, claw marks and other traces of activity are seen suggest that theregion’s favorable environment provides them with a supportive habitat. The close proximity of thesalmon-rich Horoman River and the alpine zone of Mt. Apoi with its abundance of dwarf stone pinecones – both of which are important for brown bears – create an environment found in few places inJapan.
Often referred to as relics of the Ice Age, Japanese pikas are generally seen as an alpine species inJapan. However, they are also found in areas at an altitude of only 50 meters or so in the HoromanRiver basin, which is known as their lowest-altitude habitat in Hokkaido (Fig. B-29). Pikas inhabit thecrevices between rocks on talus landforms, and geological conditions supporting the creation of such
- 22 -

Mt.Apoi Geopark,Japan

landforms are essential for their survival.
Hokkaido sika deer – Japan’s largest herbivorous animal – are also a typical mammal found on
Mt. Apoi and in the surrounding area. It is thought that they used to winter together in the region due
to its limited snowfall. However, the sika deer population has recently grown significantly, leading to
the disappearance of broad-leaved saplings and the decline of bamboo grass in woodland areas. There
are also concerns over their possible impacts on rare plant species in alpine zones (Fig. B-30).
(1)Fig. B-29 Japanese pika

(2)

Fig. B-30 (1) Traces of bamboo grass grazed by Hokkaido sika
deer; (2) installation of deer fences to support investigation of sika
deer’s impacts on alpine plants

Around 150 bird species are known to inhabit the region, andraptors such as falcons, buzzards and mountain hawk-eagles are often
sighted. As falcons nest on precipitous terrain, the coastal cliffs near Mt.
Apoi and in the surrounding area serve as prime nesting places. In
winter, Steller’s sea eagles and white-tailed eagles – both designated as
Natural Monuments of Japan – fly from the Eurasian continent to thecoastal area of Japan. Black woodpeckers – also a Natural Monumentof Japan – are often seen in forests at the foot of the mountain. In theridge area, spotted nutcrackers are frequently observed feeding on
dwarf stone pine cones and Kitagoyo (P. parviflora var. pentaphylla)
trees.
A small snail species named Apoimaimai (Paraegista apoiensis)
inhabits Mt. Apoi and the surrounding area. It is endemic to themountain and is found in cracks between peridotites (Fig. B-31). Its
brown shell, which measures around a centimeter in diameter, has hardhairs on its surface. It is suggested that the region’s unique geologicalenvironment, as represented by its peridotites, facilitated this speciation.
A
rare
disjunct-distributionsnail
speciesknown
asKadobarihimemaimai (Ainohelix editha var.) also inhabits Mt. Apoi
and its surroundings (Fig. B-32).
A notable insect species is the Himechamadaraseseri (Pyrgus
malvae) butterfly from the Hesperiidae family. It is found extensively
in northern parts of the Eurasian Continent, but its only habitat in Japanis Mt. Apoi and the surrounding area (Fig. B-33). The larval food plantof this species is almost exclusively Kinrobai (Potentilla fruticosa var.
rigida) – a rare species from the Rosaceae family. The region is also
home to Apoikiashioobuyu (Prosimulium apoina n. sp.) – an insect
described as a new species.

Fig. B-31
Apoimaimai(Paraegista apoiensis)

Fig. B-32
Kadobarihimemaimai (Ainohelix editha
var.)Fig. B-33
Himechamadaraseseri(Pyrgus malvae)(3) Bounties of the Sea off Mt. Apoi
The coastal waters off the Hidaka region, where Mt. Apoi Geopark is located, contain seaweed beds
providing habitats for kombu kelp and other forms of marine life. The kombu beds play a very
important role in conserving biodiversity and enhancing fishery output by serving as places of primary
production in this cold-sea area and acting as an environment for a variety of fish and shellfish.

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Mt.Apoi Geopark,Japan

The kombu kelp species found along the coastof Mt. Apoi Geopark are Chigaiso (Alaria
crassifolia Kjellman), Aname (Agarum clathratum
Dumortier), Sujime (Costaria costata (C. Agardh)
Saunders) and Mitsuishi (Laminaria angustata
Kjellman). Local growth of Ma Kombu (Laminaria
japonica Areschoug) has also been observed. Amongthese, Mitsuishi Kombu, also known as Hidaka
Kombu, is the main type of seaweed found in thesebeds and is an important resource, accounting for
approximately 30 percent by value of the region’s
overall marine production. The species is not foundFig. B-34 Distribution of local kombu kelp
outside Japan, and thrives mainly along the Pacific
Coast of Hokkaido around Mt. Apoi Geopark (Fig. B-34).
It generally grows with Chigaiso and Sujime kelp on
rocks in relatively shallow waters from the intertidal zone
to depths of 8 meters or so. In the coastal waters off Mt.
Apoi Geopark, masses of long Mitsuishi Kombu kelp
grow densely at depths of 3 meters and less. Its
appearance when exposed at low tide is a magnificent
sight (Fig. B-35). At the eastern end of its distributional
range, the species is replaced by Naga Kombu (Laminaria
longissima Miyabe). The results of recent molecularphylogenic studies have suggested that Mitsuishi Kombu Fig. B-35 An exposed Mitsuishi Kombu
evolved from Naga Kombu and underwent speciation into community at low tide
Ma Kombu along the Pacific Coast of western Hokkaido. It has a close phylogenetic relationship withNaga Kombu, and genetic analysis shows that the two species form a phyletic group among Japanese
kombu types. No other species in the world are included in this group.
Mitsuishi Kombu was first noted in a publication by Swedish botanist F. R. Kjellman based on
his research on dried kelp for export to China. He had obtained the kelp from an English trading
merchant in Hakodate during a visit to Japan on a scientific expedition ship in 1879. The kelp products
he purchased are thought to have been Urakawa Kombu (“Uragaiva
Combu”), Samani Kombu (“Shamani Combu”) and Tokachi Kombu(“Tokatsu Combu”), suggesting that the species has been produced in
the area from the Hidaka region to the eastern Tokachi region sincethen, and that the coastal area of Samani has long been a production
area for this kelp variety.

B-4-3. Local History and Culture Relating to the Region’s
Geological Features(1) Ainu Hardships and their Restoration as an Indigenous
People
The culture of the indigenous Ainu people of Hokkaido is considered
to have originated with the marine-centered Okhotsk culture(400-800CE) and Satsumon culture (600-1100CE), which wasstrongly influenced by the culture of Honshu (Japan’s main island).
While the Ainu subsisted on hunting, fishing, and gathering, they
were also traders who traveled across the Tsugaru Strait to Honshu
and across the Soya (La Perouse) Strait to Sakhalin and the Eurasiancontinent. Hokkaido was a crossroads of civilization where Japanese- 24 -

Fig. B-36
Kelp (Kombu) Harvesting(Byozan Hirasawa, 1822–1876)

Mt.Apoi Geopark,Japan

culture met with the culture of the continent (Northeast Asia). The goods Ainu people sold included
pelts from land and sea animals (e.g., sea otters, seals, and sables), eagle and hawk tail feathers,
salmon, and kombu kelp. From the Middle Ages onward in particular, kelp was a main trade item inthe Hidaka region (Fig. B-36).
However, the increasing number of wajin (people of ethnic Japanese descent) from Honshu who
settled in Hokkaido in subsequent years gradually wrested the initiative of free trade from the Ainu.
When a trading system favoring wajin was established in the 18th century, Ainu people, who had been
producers and trading partners with the wajin, were forced to work and suffered great hardships
including discrimination and forced assimilation by the wajin.
In the 20th century, efforts to restore the Ainu as an indigenous people gained momentum. They
were encouraged to engage in activities that would preserve their unique language and traditionalrituals as well as other aspects of their culture. In Mt. Apoi Geopark as well, initiatives to promote theindigenous culture have remained ongoing, including the preservation of traditional dance and therestoration of cise (traditional Ainu dwellings) (see pp. 5 and 21).
(2) The Dawn of Samani Supported by Early-Modern Distribution Routes
In the 18th century, Japan witnessed full-scale development of its commodity economy anddistribution. With Osaka, often called the “Kitchen of the Nation,” and northern Japan connected byroutes across the Sea of Japan, large volumes of goods were traded (Fig. B-37). The routes extended to
the Kuril Islands just to the east of Hokkaido. Against this background, the region drew attention as animportant trading hub connecting the Kuril Islands and Japan’s main island of Honshu because Mt.
Apoi was a landmark when viewed from the sea, and more importantly, Cape Enrumu (a land-tiedisland composed of intrusive rock) served as a natural port (Fig. B-38).
In 1799, the Edo Shogunate that ruled Japan took the southern half of Hokkaido under its directcontrol in response to a sense of urgency over Russia’s ongoing southward expansion along the Kuril
Islands via the Kamchatka Peninsula. The shogunate established a kaisho (outpost office) at the baseof Cape Enrumu and built Tojuin Temple as part of efforts to win the hearts and minds of locals. To
facilitate the dispatch of troops for Hokkaido’s defense, the shogunate also constructed Hokkaido’s
first government-administered road, known as the Samani Mountain Path, on the sea cliffs (Hidaka
Yabakei) to the south of Mt. Apoi.
These developments are discussed as important themes in local history, and documents describing
them along with related structures and ancient structural remains have been designated as culturalproperties in recognition of their value in terms of local historical heritage.

Fig. B-37 A kitamaebune
merchant vessel and Meiji
Period (1868 – 1912)
marine routes

Fig. B-38 Cape Enrumu and Mt. Apoi, painted
around 150 years ago (“Hokkaido Rekiken-zu,”
Samani)(3) Kombu Kelp Harvesting – an aspect of local culture for the past 400 years
Commercial harvesting of local Mitsuishi Kombu is considered to have begun between the mid-17th
century and the 18th century. Much of the kombu kelp harvested in those days was transported to
Osaka in western Japan for the manufacture of kizami-kombu (dried shredded kelp), which laid the- 25 -

Mt.Apoi Geopark,Japanfoundations for the city’s development as a kelp
processing center. As this kelp species contains highlevels of iodine, it was also exported to China whereiodine deficiency was a serious problem, and wasused for goiter treatment (Fig. B-39). Its soft fiber
also makes it suitable for simmered dishes, and it
creates a mild flavor when used to make soup stock.
Due to a variety of uses not shared by other species,
Hidaka Kombu – the commercial name for Mitsuishi
Kombu – is widely known in Japan and is anindispensable part of the national diet. It is versatileand popular with the general public, but theFig. B-39 Kombu Road
differences in the areas along the Hidaka coast
where the kelp is harvest, known as shore disparity,
leads to variations in its commercial value. Different shores are ranked as extra- high quality, highquality, medium and regular, and prices depend on where kelp is harvested. Today, extra-highand high-quality shores are found in Samani, where Mt. Apoi Geopark is located, and intowns adjacent to it on both sides. However, Samani is the only town where all fisherydistricts are ranked as high-quality or above (Fig. B-40). This rich resource supports thediet of the Japanese both qualitatively and quantitatively.
Throughout the long history of Hidaka, Kombu harvesting and production areas have often faceddifficulties. These have included devastation of fishing grounds by oil pollution, environmental
degradation of fish habitats due to deforestation, and the decline of trade with China. However, thesecrises were overcome by the untiring efforts of local fishermen and related parties. Such work has
involved fishing ground improvement, product enhancement resulting in the production of sand-freekelp, drying ground improvement, and market expansion campaigns. In this way, traditional local
industry has been preserved (Fig. B-41).

Fig. B-40 Differences in the commercial value of
Hidaka Kombu among different production areas

Fig. B-41 Kelp harvesting using hooks thathave remained unchanged for 400 years- 26 -

Mt.Apoi Geopark, Japan

C. Geoconservation
C-1. Current or potential pressure on the proposed Geopark
C-1-1. Peridotite Mining
Peridotite mining has been under way for more than half a century at the southwestern margin of the
Horoman peridotite complex (Figs. C-1 and C-2). As this rock is hard and fire-resistant with a highmagnesium content, it is in great demand as an industrial material. The local quarry company – Toho
Olivine Kogyo Co., Ltd. – supports the regional economy in its role as a local-capital company. The
mined area so far covers approximately 330,000 m2, which accounts for 0.8% of the total area ofoutcrops in the Horoman peridotite complex.

Fig. C-1 Extent of Horoman peridotite
complex outcrops and quarry location

Fig. C-2 Peridotite quarry and plantC-1-2. Decline of Alpine Flora
Along with peridotites, Mt. Apoi’s alpine plant communities are valuable natural heritage resources of
Mt. Apoi Geopark, but their decline is proceeding at a rapid pace (Fig. C-3). Although the cause of thedecline is yet to be fully established, it is assumed that many years of plant harvesting by various
hikers for personal gardens and flower shops has exacerbated a situation already made problematic byelements of environmental change such as global warming.
1977

1989

2007

Fig. C-3 Disappearance of rocky areas (i.e., habitats for flowering plants) due to the expansion of dwarf
stone pine habitats near the Umanose area of Mt. Apoi

C-2. Current status in terms of protection of geological sites within the
proposed Geopark
C-2-1. Regulations Against Peridotite Mining
The peridotite quarry in Fig. C-1 is located in a Class III Special Zone of Hidaka-sanmyaku Erimo
Quasi-National Park according to the Natural Parks Act (Fig. C-4). Any and all large-scale mining isessentially prohibited in such zones. However, the Hokkaido Prefectural Government granted special- 27 -

Mt.Apoi Geopark, Japan

permission to mine in the minimum
required area in consideration of theregional economic effects that could arise
if the quarry operator withdrew from thearea and the fact that the operator also
worked there before it was designated asa quasi-national park. The minimum
required area is interpreted as beingaround the current mining location, whichis in the Horomankyo Area of Mt. Apoi
Geopark but is not a geosite.
The Mt. Apoi Geopark website
provides information on applying forindividual permission to collect sand andstones within the quasi-national park, andon other matters concerning relevant
regulations.
Fig. C-4

QuarryScope of regulations in Hidaka-sanmyaku Erimo Quasi-National Park and quarry location

C-2-2. Protection and Restoration of Alpine FloraAs shown in Fig. C-4, Mt. Apoi and the surrounding area are part of Hidaka-sanmyaku Erimo
Quasi-National Park. Development activities and any other changes to current conditions in the area
are subject to regulation. In particular, the ridge from Mt. Apoi to Mt. Pinneshiri and the summit areaof Mt. Horoman, where alpine plants grow, are designated as Special Protection Zones and are thus
subject to highly stringent regulations. In these zones, the Hokkaido Prefectural Government (thequasi-national park’s administrator) regularly makes patrols to check for illegal digging of flora.
Members of the Mt. Apoi Supporters’ Club (a member organization of the Mt. Apoi Geopark
Promotion Council in Samani) engage in a range of initiatives, including patrols, mountain trail
development, alpine plant restoration, investigation of deer-related plant damage, and publicawareness activities (Fig. C-5).
The alpine plant restoration initiative is intended to secure habitats for growth by removing dwarf
stone pines and other plants. Restoration testing involving experimental surface soil disturbance is also
conducted (Fig. C-6).
(1)

Fig. C-5 Mt. Apoi Supporters’
Club campaign to prevent illegal
digging(2)

Fig. C-6 (1) Samaniyukiwari (Primula modesta var. samanimontana)in bloom at the Alpine Plant Restoration Test Site; (2) test cutting of
dwarf stone pines

C-3. Data on the management and maintenance of all heritage sites
Concerted efforts are made by both the public and private sectors to protect the environment of Mt.
Apoi. Two rangers and an alpine patrol from the Hokkaido Prefectural Government, which is thequasi-national park administrator and landowner, regularly conduct checks in the area. Additionally,
15 members of the Mt. Apoi Supporters’ Club conduct frequent patrols to prevent illegal alpine plant- 28 -

Mt.Apoi Geopark, Japan

digging under commission from the Hokkaido Government.
In areas other than Mt. Apoi, local residents have
implemented annual cleaning for more than 30 years, thereby
helping to maintain the environment of Mt. Apoi Geopark (Fig.
C-7).
Fig. C-7 Annual springtime cleanup volunteer operation

D. Economic Activity and Business Plans
D-1. Economic Activity in the proposed Geopark
D-1-1. Fisheries
The waters off Mt. Apoi Geopark are known as good fishing grounds thanks to the confluence of thewarm Tsushima and Kuroshio currents and the cold Oyashio Current. The region’s rich marine
resources include salmon, cod, flounder and other fish, kombu kelp and other types of seaweed, andaquatic life such as octopuses and squid. Fisheries are a key local industry employing more than 500
people (significantly more than other industries) according to the 2010 population census, although theyield in fiscal year 2011 amounted to only around 2.5 billion yen (approx. 23 million US dollars). Dueto a noticeable dwindling of resources in recent years, particular efforts have been made to enhancetheir sustainability. These have included fishing-ground improvement, aquaculture promotion, and theadjustment of fish catches.
D-1-2. Agriculture and Forestry
Geographically speaking, most of the region consists of rolling hills and mountainous terrain
stretching from the Hidaka Mountains. Accordingly, only a fraction of the land is suitable for crop
cultivation. However, local farmers are able to grow Apoi Rice using low amounts of agriculturalchemicals and cultivate strawberries thanks to the cool temperate climate.
Over 90% of Mt. Apoi Geopark is covered by forestland, but production activities in forestry havebecome sluggish due to lower timber prices caused by an influx of imported wood and other factors.
However, forests are systematically developed with public funding to maintain their multiple functions,such as watershed conservation, disaster prevention in mountainous areas, and the conservation of thearea’s living environments.
D-1-3. Mining and Manufacturing Industries
Industrial product shipment in fiscal year 2010 amounted to around 10 billion yen (approx. 93 million
US dollars) – the highest in the Hidaka region. This is largely due to hydroelectric power generation
capitalizing on the topography of the peridotite gorge, as well as peridotite and limestone mining in thepermitted area.
D-1-4. Tourist Industry
Around 100,000 tourists who visit the region annually participate in many activities, including
climbing Mt. Apoi, camping, and attending events. On average, 7,000 to 8,000 people climb Mt. Apoi
every year, accounting for the core of long-stay tourism in the area. Despite the fundamental problem
of a lack of accommodation, geopark activities have gradually helped to improve the region’s
preparedness to host visitors. These include the development of new products (e.g., souvenirs) and theestablishment of a guide system. Accordingly, the number of tourists visiting the region is expected to
grow in the future.

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Mt.Apoi Geopark, Japan

D-2. Existing and planned facilities for the proposed Geopark
D-2-1. Educational and Research Facilities
Mt. Apoi Geopark Visitor Center
In April 2013, the old visitor center for climbers on Mt. Apoi wasrenovated to create the Mt. Apoi Geopark Visitor Center. The centerhas drawn around 28,000 visitors over the past two years, during
which it was in actual operation only for 16 months. As the principal
facility of Mt. Apoi Geopark, it provides information andopportunities to learn about the region’s geology and nature as well
as related history and culture. Exhibit commentaries on geology areprovided in two levels; they are essentially tailored to junior high school students, but simple
illustrations are also shown to help elementary school students grasp the basics.
Samani Folk Museum
This museum showcases local history. It exhibits some remarkablepieces despite its small scale, including old documents held by
Tojuin Temple (which are collectively designated as a National
Important Cultural Property), Ainu artifacts, and documents of the
Yamoto family that give insights into the early-modern days of
Hokkaido’s development. A historian will be employed in fiscal year
2015 to improve the exhibition environment through enhanced
investigation and research.
Mt. Apoi Peridotite Plaza
This town-center outdoor rock museum primarily showcases
polished peridotite, but also displays other cut and polished rocks
from the Hidaka Mountains. All the specimens are highly polishedto facilitate identification of the individual minerals contained
within. The plaza is a popular site for university geological field
trips.

GeoLAB Mt. Apoi
This laboratory in the science lab of a former elementary school
showcases rock specimens collected over many years by a Horomanperidotite researcher who was an associate professor at Hokkaido
University. It is a regional hub for earth science studies.

Mt. Apoi Research Support Center
This budget accommodation facility (500 yen per night) caters toresearchers by supporting university field trips as well as fieldworkin Mt. Apoi Geopark and the surrounding area. The facility
promotes exchanges between locals and researchers, and benefits
local communities based on the fruits of research.

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Mt.Apoi Geopark, Japan

D-2-2. Geotourism and Tourist Facilities
Apoi Sanso HotelThis hotel is the area’s largest tourist accommodation facility. It also
serves as a base camp for people climbing Mt. Apoi, and is locatedin Sanroku Park where the Mt. Apoi Geopark Visitor Center is also
found.

Samani Tourist Information Center
This center in JR Samani Station (the railway line terminus)
provides a wealth of information despite its limited size, such asdetails of Mt. Apoi Geopark and local excursions. The center isstaffed by a guide and also sells local specialties and souvenirs.

Tojuin Temple – one of three temples established in
Hokkaido by the Edo shogunate
This temple was established in 1806 by the ruling Edo Shogunate. It
is one of three temples founded in Ezo (known today as Hokkaido)
by the shogunate as part of efforts made to win the hearts and mindsof locals due to fears of possible invasion by foreign troops(particularly Russians) into Hokkaido, which was recognized as aborder island.
Mt. Apoi Geopark Visitor Center
The old visitor center for climbers on Mt. Apoi was renovated to create the Mt. Apoi Geopark Visitor
Center and reopened in April 2013. As the principal facility of Mt. Apoi Geopark, the center fulfills thedual functions of giving information and providing learning opportunities.
Oyako-iwa Fureai BeachThis seaside beach is situated on the foreshore of the Oyako-iwa Rocks, which are seen as a symbol of
the area along with Mt. Apoi. Tourists flock to the beach in summer.
Campsites
Non-demarcated campsites are located at the foot of Mt. Apoi, at Oyako-iwa Fureai Beach and at the
Samani Dam.

D-3. Analysis of geotourism potential of the proposed Geopark
D-3-1. Strengths
・Mt. Apoi is highly significant in Japanese and international academia due to the large number of
low-altitude endemic alpine plants that grow only here. This mountain of flowers fascinates those
who climb it.
・Mt. Apoi is located at a point where the mantle deep in the earth was pushed onto the surface. Mt.
Apoi Geopark is Japan’s only area where the perception of global-scale dynamic ground movement
differs from that experienced with volcanoes.
・The beautiful olive green peridotites visible above ground on Mt. Apoi are large even by international- 31 -

Mt.Apoi Geopark, Japan

standards, and are relatively pure in that they remain in the condition of their time in the mantle.
They are a globally rare resource by which the inaccessible mantle can be viewed.
・The geopark features scenic landscapes with mountains providing striking contrast against coastal
areas.
・The geopark area has witnessed the history of human societal development supported by its beautiful
coastal terrain, and is therefore characterized by clear narratives connecting people with the earth.
・The geopark area is home to an established network of families engaging in agriculture, forestry andfisheries who can host students in their houses.
D-3-2. Weaknesses
・At first glance, the geopark area does not seem like a place to experience and learn about the Earth’s
dynamic movements
・Access to the area is inconvenient, as it is far from major cities and airports.
・There is room for improvement in terms of visitor readiness regarding the limited number ofaccommodation facilities, as well as the limited availability of local specialties, souvenirs,
restaurants serving local food, guided tours, hands-on programs, and other products and services.
D-3-3. Future Vision
As Mt. Apoi Geopark suffers from population dispersion and insufficient preparedness to host tourists,
there would be little geotourism potential if the Mt. Apoi Geopark Promotion Council in Samani
simply waited for tourists to turn up. There is a need to identify target demographic visitors anddevelop locally unique excursions and hands-on programs to meet demand. In order to add value andextend periods of stay, geological narratives should also be provided to people who come to see Mt.
Apoi’s renowned alpine plant communities.
It is additionally important to develop appealing food and other products and to improve guidance
among other services. The success or failure of hands-on tours depends on user-friendly guidance andunique, delicious, local food. Mt. Apoi Geopark’s accommodation capacity must also be improved incollaboration with neighboring areas, and this should include the utilization of homestay programs forstudents. While enhancing visitor-readiness, the Mt. Apoi Geopark Promotion Council in Samani alsoplans to promote strategic marketing activities in order to develop geotourism as a key local industry.

D-4. Overview and policies for the sustainable development
D-4-1. Geo-tourism and economy(1) Hands-on tours to attract tourists
The Mt. Apoi Geopark Promotion Council in Samani plans and implements guided tours for mountainclimbing, footpath walking, vocational experiences, and other activities. These are intended tohighlight the magnificence and bounty of the geo-heritage that underpins local life here through avariety of hands-on programs. In this regard, the Council will step up its efforts while incorporating
creative ideas in these endeavors. In particular, in recognition of the geopark’s unique coastal
topography stemming from Mt. Apoi’s proximity to the sea, steps are being taken to create
infrastructure for the realization of marine geo-tours using fishing boats (Fig. D-1).
The geopark offers various tourist information resources, such as a dedicated website, literature(i.e., guidebook, handbook, pamphlet and leaflet publications), signboards, and a smartphone map app(Fig. D-2). Tools available in languages other than Japanese include a pamphlet (a partial translation ofa Japanese pamphlet into English and Chinese), a leaflet (in English), signboards (in English) and a
website (a partial translation of the Japanese website into English). Publication of a new English
leaflet is also planned for fiscal year 2014, and more English information will be provided on thewebsite and via the smartphone map app.

- 32 -

Mt.Apoi Geopark, Japan

Fig. D-1 Experimental geo-tour
using a fishing boat

Fig. D-2 Pictorial map information
accessed using a smartphone app

Fig. D-3 Geopark guide

The remodeled Mt. Apoi Geopark Visitor Center is the primary facility from where geosite tours
begin. However, as its location at the foot of Mt. Apoi may not be optimal for tourists, the Mt. Apoi
Geopark Promotion Council in Samani plans to further enhance the information function of the Tourist
Information Center in the town center. The Council will also provide information to guide visitors to
the Tourist Information Center.
Presently, Mt. Apoi Geopark has 12 geopark guides. The Mt. Apoi Geopark Promotion Council in
Samani, which is responsible for providing guide services, assigns guides to meet individual needs
based on requests submitted using the form on the website (Fig. D-3). Requests for English-speaking
guides are fulfilled by a local resident who is fluent in English and two assistant English teachers
working at local elementary and junior high schools.
(2) Utilization of Local Industries
Tours have helped to raise the profile of local products by bringing
visitors to commercial establishments in fisheries and other local
industries for hands-on experience opportunities. As workers in various
industries serve as geopark guides, they also enhance the entire area’s
involvement in efforts to promote geotourism. The Mt. Apoi Geopark
Promotion Council in Samani will continue to develop tours incollaboration with local industries (Fig. D-4).
Previously, fish, shellfish, and farm produce from the area wereseldom sold over the counter or subjected to secondary processing forsales. However, a shop selling local fishermen’s catches has now been
established, and geopark-related souvenirs and other products havebeen developed. Additionally, to promote local cuisine, the Apoi Sanso
Hotel has collaborated with a neighboring hotel to develop new menu
items made with seasonal ingredients (Fig. D-5), and a restaurant
serving food made with locally produced ingredients has been opened.
The logo and mascots of Mt. Apoi Geopark are also used to provide
added value to existing products. The Mt. Apoi Geopark Promotion
Council in Samani will continue to promote relationships between thegeopark and the local economy.

Fig. D-4 A tour to observe
fixed-net fishing for chumsalmonFig. D-5 New menu fair hosted
by a local hotel

Fig. D-6 Vocational experience involving high school students at athoroughbred horse farm as part of programs in which students stayat the homes of agriculture, forestry and fisheries operators(3) Hosting of School Field-Trip Students in Private Homes
Since fiscal year 2012, high school students on field trips from the western part of Japan’s main islandof Honshu have been hosted in Mt. Apoi Geopark. This initiative is intended to provide opportunities
for students to stay in small groups at the homes of local farmers and fishermen to experience theirwork. Students from five schools visited the area in fiscal year 2014 (Fig. D-6). Although geotourism- 33 -

Mt.Apoi Geopark, Japanis not yet a part of these tours, such a development will be examined in light of the significant
potential of private accommodation usage to combat the area’s limited number of beds.
D-4-2. Geo-education : Education Capitalizing on Geo-Heritage(1) School Education
The area has an elementary school and a junior high school (Samani
Elementary School and Samani Junior High School) at which
community studies of Mt. Apoi Geopark are promoted primarily as
part of general studies.
In academic year 2013, groups of first-year students from Samani
Junior High School investigated natural heritage resources (e.g.,
peridotites and alpine plants), local industries (e.g., hydroelectric
power generation), and the history of the town, and then made poster
presentations on their findings (Fig. D-7). Sixth-grade students at
Samani Elementary School also developed geopark tour routes andmade sightseeing pamphlets. In addition, sixth-graders at theneighboring Urakawa Elementary School studied the compositions of
Mt. Apoi and the Hidaka Mountains in science classes (Fig. D-8).
At Urakawa High School, community studies on Mt. Apoi
Geopark are part of the curriculum. Students there studied the originsof the Hidaka Mountains and alpine plants on Mt. Apoi in academic
year 2013 (Fig. D-8). In future work, more systematic programs will
be developed with emphasis on earth science and local area studies atschool.
Education that makes use of the geopark is expected to havevarious positive effects, not only giving students an understanding ofearth science but also developing their ability to pursue knowledge,
enhance their communication skills, and broaden their perspectives.
The local population is rapidly decreasing, due mainly to an outflow
of school graduates and a low percentage of people coming back to
the area. The Mt. Apoi Geopark Promotion Council in Samani plans toencourage people to return by promoting a range of educational
initiatives focusing on the area, such as earth science studies.
(2) GeoLAB Mt. Apoi
In 2012, the GeoLAB Mt. Apoi laboratory was opened in a renovatedclassroom of an old elementary school at the foot of Mt. Apoi. The
director, who was previously an associate professor at a Hokkaido
University graduate school, has long researched the Horomanperidotites and organizes public workshops in conjunction with acurator in geology (Fig. D-10). GeoLAB Mt. Apoi also supports
researchers visiting the geopark in its role as a local research hub.

Fig. D-7 Investigative learning at
the visitor center (first-year
students from Samani JuniorHigh School)

Fig. D-8 Extra-curricular science
lessonongeologicalcomposition (sixth-graders fromUrakawa Elementary School)

Fig. D-9 Earth science class at
Urakawa High School

Fig. D-10 Public workshop at
the GeoLAB Mt. Apoi laboratory(3) Disaster Management Education
The Great East Japan Earthquake caused unprecedented damage to Japan and left deep scars in Mt.
Apoi Geopark. The 3.3-meter-high tsunami that hit the area around 30 minutes after the earthquake
caused more than 700 million yen worth of damage (approx. 6.5 million US dollars) to the inundated
area around the fishing port (Fig. D-11). Fortunately there were no human casualties thanks to prompt
evacuation.

- 34 -

Mt.Apoi Geopark, Japan

Because Samani is located to the southwest of the Hidaka
Mountains and facing the Pacific Ocean, the area is occasionallyaffected by trench earthquakes. This has prompted the local
government to take a range of disaster management initiatives,
including the formulation of a local disaster management plan, theinstallation of a disaster prevention radio system in the coastal area,
the establishment of disaster management organizations and theimplementation of disaster drills. However, the Great East Japan
Earthquake necessitated fundamental reviews of these efforts. New
initiatives currently under development include the formulation of atsunami evacuation plan and a hazard map, the implementation ofevacuation drills, the installation of sea level signs, emergency
stockpiling and the designation of evacuation routes (Fig. D-12).
Ongoing efforts will be made to ensure that local residents shareaccurate information on disasters and remember the damage caused in
2011.

Fig. D-11 Samani Fishing Port– a site damaged by the Great
East Japan Earthquake

D-4-3. Geo-heritage and researcher support
Fig. D-12 One of 130 sea level
The area has supported exchanges with researchers primarily in signs installed in the area
geology and ecology since before the geopark designation. In 2013, a
total of 344 researchers and university students from 30 institutions visited Mt. Apoi Geopark (Fig.
D-13). The expansion of exchanges is largely attributed to the Mt. Apoi Research Support Center – aself-catering accommodation facility at the foot of Mt. Apoi. Its exceptionally low prices (500 yen per
night, 250 yen per night for the 15th night onward) are popular with researchers investigating the area
and those on university geological field trips (Fig. D-14).
Thanks to this support, three international conferences on earth science have been held in the area(the 2nd Joint Meeting of the Korean and Japanese Structure and Tectonic Research Group in 1999,
the 4th International Workshop on Orogenic Lherzolite and Mantle Processes in 2002, and the Ocean
Drilling Program (ODP) Leg 209 post-cruise meeting in 2005). The area was also commended by theJapanese Association of Mineralogists, Petrologists and Economic Geologists in 2002 and the
Geological Society of Japan in 2003 (Fig. D-15) for its efforts to support research.
The Mt. Apoi Geopark website provides researcher support resources such as forms to request
accommodation at Mt. Apoi Research Support Center, information on the regulatory procedures to befollowed for access to the quasi-national park and other areas, and a database of academic papers.
Renovation of the aging Research Support Center is also planned. Efforts will be continued to support
researchers in order to ensure the conservation of geological and natural heritage resources and benefit
local communities through research.

Fig. D-13 One of many
university field trips annuallyconducted in Mt. Apoi Geopark

Fig. D-14 Mt. Apoi Research
Support Center- 35 -

Fig. D-15 ODP Leg 209
post-cruise meeting (2005)

Mt.Apoi Geopark, Japan

D-5. Policies for, and examples of, community empowerment (involvement andconsultation) in the proposed Geopark
(1)

(2)

D-5-1. Public Workshops
To support sustainable development inprovincial areas, local residents must haveaffection for and a sense of identity with
their hometowns. To this end, in 2010 the
Mt. Apoi Geopark Promotion Council in
Samaniintroduced
Hometown(3)
Geo-workshop lectures to highlight thearea’s appeal. Over the past four years,
around 1,500 local residents have attended
workshops designed to provide education on
the area and support the development ofguides. Attendees learn about all the
resources of Mt. Apoi Geopark (geological,
Fig. D-16 Hometown Geo-workshop lectures:
ecological, and human) via presentations (1) the head priest of Tojuin Temple gives a lecture;
given by university professors and (2) a local historian explains the origins and history ofrocks from Mt. Kannon (Geosite C4);
researchers as well as by local residents, coastal(3) a technical expert describes the mechanism behindincluding teachers, experts, company owners, hydroelectric power generation leveraging the gorge
office workers, shopkeepers, fishermen, and landform
even the head priest of a temple. Inviting locals to present has helped to promote public awareness andparticipation in geopark-related activities (Fig. D-16).
Although the focus of the workshops has been shifted more toward guide training in fiscal year
2014, local residents in various fields will continue to present in their roles as Samani experts. This
will help to increase the number of local residents who come to the geopark as a place to learn about
and enjoy local history and resources.
D-5-2. Local Resource Conservation and Utilization based on Public Participation
In the area’s key industry of fisheries, kombu kelp harvesting is a traditional activity that has continued
since the Ainu culture period. The harvesting method is quite simple: a fisherman in a surf boat withan outboard engine pulls the seaweed from rocks using a long-handled hook and spreads it over apebbled site for sun-drying. Once the kelp is dry, it is simply cut to the right length, bound according
to quality and shipped. As sun-drying of kelp is labor-intensive, many locals work part-time tocomplete the task (these part-timers are referred to as okamawari, meaning “post-harvestingland-based workers”). As such, kelp harvesting forms an essential part of local culture as well as
supporting the regional economy.
The two initiatives described below are implemented at Mt. Apoi Geopark to ensure theconservation and utilization of kelp.
(1) Kelp ForumThe annual Hidaka Kombu Forum highlights
the crop’s role in supporting the local economy
and regional culture. Attended by local
fishermen and residents, it is intended topromote consideration for the future of kelp,
Fig. D-17 Hidaka Kombu Forum in Sapporo (2011)
which is an important part of Japan’s foodculture. The forum has also been held in Sapporo, which is a major neighboring area of consumption(Fig. D-17). The event features discussions on various kelp-related topics such as resource
conservation, production, processing, and recipes.
- 36 -

Mt.Apoi Geopark, Japan(2) Conclusion of a Comprehensive Partnership Agreement with Hokkaido University
Among Hidaka Kombu-producing areas, Mt. Apoi Geopark ranks
highly both qualitatively and quantitatively. In particular, the sea
cliff area at the southern foot of Mt. Apoi is known for producing
some of the highest-quality Hidaka Kombu available. The reason
why such outstanding kelp grows in the marine zone is yet to beunderstood, but the peridotite (ultramafic rock) of Mt. Apoi isconsidered to be a factor. Generally, soil derived from ultramaficrock has a high content of metals such as iron and magnesium,
which are both important for kelp growth even in extremely small
Fig. D-18 Environmental survey
quantities.
by the Hokkaido University Field
Against this backdrop, the government of Samani Town – the Science Center for Northernhome of Mt. Apoi Geopark – concluded a comprehensive Biospherepartnership agreement with the Hokkaido University Field Science Center for Northern Biosphere to
jointly investigate the causal relationships between favorable kelp growth and local conditions (Fig.
D-18).
The decline and disappearance of kelp beds due to changes in the marine environment havebecome serious issues across Hokkaido. Although such beds are still extensively found in the coastal
area of Mt. Apoi Geopark thanks to the area’s unique environmental conditions, the protection of theseunderwater forests requires understanding and conservation of the entire area, including the terrestrial
zone.
Collaborative survey work conducted by the university and local fishermen has led to a review ofapproaches in the fishing industry based on recognition of the need for resource conservation andmotivation to provide added value for consumers.
D-5-3. Exchanges with other geoparks(1) Japanese Geoparks Network
Japan currently has 7 Global Geoparks and 28 Japanese Geoparks,
all of which engage in lively mutual exchanges. Mt. Apoi Geopark
staff also work to improve local quality through exchanges andcollaboration with other geoparks. Such efforts have included
proactive participation in research meetings and the dispatch ofguides for training at the Toya Caldera and Usu Volcano Global
Geopark in fiscal year 2013 (Fig. D-19).

Fig. D-19 Guide training at Mt.
Showa-Shinzan (Toya Caldera
andUsu
VolcanoGlobalGeopark)(2) Global Geoparks Network
Representatives of the Mt. Apoi Geopark Promotion Council in Samani have attended the International
UNESCO Conference on Global Geoparks since its fourth meeting in Langkawi, and continue to makepresentations as part of efforts toward Global Geoparks Network (GGN) membership. The Council
seeks active exchanges with other regions based on the peridotite characteristics of the area. At the2014 6th International UNESCO Conference on Global Geoparks in Stonehammer, Canada, theCouncil held discussions with representatives of northern Italy’s Sesia-Val Grande Geopark, which isalso a peridotite site, with the idea to engage in further exchanges in the future (Fig. D-20).
In July 2014, the Council hosted a lecture meeting and a special exhibition highlighting thegeological features and geotourism of Oman in the Middle East (Fig. D-21). The events showcased the
Oman ophiolite complex (consisting of sequences of material from the oceanic crust and upper mantle
on the earth’s surface), which is often researched in reference to the Horoman peridotite complex, andwere held in collaboration with the Tokyo Embassy of the Sultanate of Oman.

- 37 -

Mt.Apoi Geopark, Japan(1)

Fig. D-20 With representatives
from Sesia-Val Grande Geopark(Stonehammer)(2)

Fig. D-21 (1) Lecture meeting and (2) special exhibition on the geology
and geotourism of Oman held at Mt. Apoi Geo Park

D-6. Policies for, and examples of, community empowerment (involvement andconsultation) in the proposed Geopark
D-6-1. Public Relations Activities
The Mt. Apoi Geopark Promotion Council in Samani engages in a variety of public relations initiatives
to promote the concept of geoparks and associated activities.
The Council provides detailed information via its website and works to publicize its daily activities
via a blog and a Facebook page. Principal efforts for communication with local residents include
presentations, geosite guidance, and PR campaigns at local gatherings, and other events such as photo
contests featuring beautiful Mt. Apoi Geopark landscapes (Fig. D-22) are organized. When planning
events, the Council also places importance on press releases and promotion to media outlets.
Mt. Apoi Geopark has two mascots that help to raise its profile. They have become established as alocal PR medium and appear on the sides of buses, traffic safety flags, clear document files anddesignated paid garbage bags (Fig. D-23).
The Promotion Council will continue its public relations activities, its hosting of symposiums, andits other initiatives to further enhance public interest in the geopark.
(1)

Fig. D-22 Photocontest poster(2)

Fig. D-23 Geopark mascot utilization:(1) on the side of a bus; (2) on a traffic safety flag

D-6-2. Merchandise Development
A variety of products bearing Mt. Apoi Geopark’s logo and mascots havebeen developed, including cell phone straps, badges, polo shirts, sake, rice,
honey and confectionery (Fig. D-24). A local company has also developed
a high-end take-home gift made with a local brand of whelk and includes
information on Mt. Apoi Geopark on its PR label (Fig. D-25).
The Mt. Apoi Geopark Promotion Council in Samani will continue toencourage local companies to develop geopark-related products while
stepping up its collaboration with stakeholders inefforts such as the introduction of Mt. Apoi Geopark
recommended product stickers on various local
products.
Fig. D-25 Whelks (a Samani specialty) pickled in spicy
soy sauce with a label featuring Mt. Apoi Geopark- 38 -

Fig.
D-24
Geopark
related merchandise

Mt.Apoi Geopark, Japan

E. Interest and arguments for joining the GGNThe Mt. Apoi Geopark Promotion Council in Samani offers a number of advantages for the Global
Geoparks Network (GGN) that would result from its membership.
One of the main characteristics of Mt. Apoi Geopark lies in the unique opportunity for visitors tosee, walk through, and come into contact with the otherwise inaccessible world of the earth’s deep
mantle. Its location in Japan and therefore within a mobile belt gives the area a feeling of global-scale
dynamic ground movement, creating an experience different from that felt in the vicinity of volcanoes.
Although peridotites are found in various parts of the world, and especially in mobile belts, few
are like those of Mt. Apoi. Here, they are of a certain size and are visible above the ground, and also
maintain information about the mantle thanks to their non-metamorphosis. As a result, international
conferences attended by peridotite researchers from around the world have been held in the area. The
Mt. Apoi Geopark Promotion Council in Samani hopes to establish collaborative international
relations with regions where peridotites are present by actively promoting this valuable geological
heritage on a global scale.
Another main characteristic of Mt. Apoi Geopark is found in its unique ecosystems, which are
greatly influenced by geological and geomorphological resources. Mt. Apoi is home to an amazingly
diverse range of alpine plant species considering its low altitude and the isolated, small area of its
alpine zone. The presence of numerous endemic (variant), disjunct-distribution, and rare species in theregion highlights Mt. Apoi’s role as a stage for plant evolution. In other words, these species would not
be present without the area’s special peridotite rock and the mountain’s formation. Few places on earth
exhibit such strong links between geological and geomorphological resources and ecosystems; Mt.
Apoi Geopark exemplifies a range of geo-narratives and guidance methods that create these ties.
The value of the geopark’s connections among geological and geomorphological resources, nature,and people would also represent a significant contribution to the GGN.
As described earlier, the main theme of Mt. Apoi Geopark is A Story of Gifts from Deep Inside theEarth connecting Land and People Together. This expresses the close relations between local residents
and peridotites appearing from far below the earth’s surface as a result of global-scale dynamic groundmovement. It also encompasses the Promotion Council’s efforts for community revitalization based onsustainable, symbiotic relations between nature and people.

Main theme:
A Story of Gifts from Deep Inside the Earth Connecting Land and People Together
Theme A: Peridotites – the interior and dynamic movement of the Earth
Theme B: Alpine Plants – scarcity and the natural environment
Theme C: Human History – the community of nature and human life
The unique geological features of peridotite and the climate of Mt. Apoi allow alpine plants togrow on this modest 810-meter peak. Local alpine plant communities including Hidakaso(Callianthemum miyabeanum) and other endemic species have been collectively designated as aSpecial Natural Monument of Japan. The pretty flowers found on the rugged peridotite terrain
highlight the close relations between geological resources and ecosystems. A number of rocky- 39 -

Mt.Apoi Geopark, Japan

monoliths along the coast to the west of Mt. Apoi form unique landscapes. These landforms, whichwere created at almost the same time as Mt. Apoi due to crustal movement and subsequent coastal
erosion, gave rise to a fine natural port that led to the development of the area today. The rich varietyof minerals contained in peridotites also supports a wealth of marine resources, and the local peridotite
landforms have led to the development of renewable energy and consequent support for local
industries.
In this way, the area has a variety of narratives to offer despite its limited scale. Mt. Apoi Geopark
promotes various educational initiatives and geotourism using these narratives in its role as a Japanese
geopark. In the meantime, the extensive involvement of residents in such activities has enhanced theidentity of local communities, which is one of the aims of geopark promotion. Mt. Apoi Geopark is
located in a very small town with a population of just 5,000. Against this background, the Mt. Apoi
Geopark Promotion Council in Samani hopes to prove that the geopark concept helps to enhance thesustainability of local communities.
The Council hereby submits its GGN membership application for Mt. Apoi Geopark. We hope thatmembership will help people around the world to experience the magnificent natural phenomena ofgifts from the deep inside the earth and see locals living together with the geo-heritage toward theultimate goal of achieving sustainable development in the area.
The Mt. Apoi Geopark Promotion Council in Samani hereby expresses its desire to join the Global
Geoparks Network in order to achieve these goals and make a truly global contribution.

- 40 -

Cited Literature and References
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Geological Survey of Japan, 2003, GEOLOGICAL MAP OF JAPAN 1:200,000 "Hokkaido", National Institute of Advanced Industrial
Science and Technology (AIST). (In Japanese)
Hunahashi, M., and lgi, S., 1956, Explanatory text of the geological map of Japan "Horoizumi" (scale 1: 50,000). Geol. Surv. Japan.,
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Kanie, Y. and Sakai, A., 2002, Quadrangle Series 1:50,000 Kushiro (2) No.69 NK-54-9-4 Geology of the Urakawa District, . Geological
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Niida, K., 1984. Petrology of the Horoman ultramafic rocks in the Hidaka Metamorphic Belt, Hokkaido, Japan. Jour. Fac. Sci.,
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Niida, K., 1997, Erimo Hometown Rediscovery Series 1: A Look into the Earth. Erimo Town Board of Education, 1-11. (In Japanese)
Niida, K., 1999, Hidaka Mountains: Rocks Generated in Deep Lithosphere beneath the Island-arc. Earth Science of the Island Arc –Where Northern Land and Ocean Meet. Hokkaido University Museum Exhibition of Academic Specimens, 22-28.
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Osanai, Y., 1985, Geology and Metamorphic Zoning of the Main Zone of the Hidaka Metamorphic Belt in the Shizunai River Region,
Hokkaido. Jour.Geol.Soc.Japan, 91, 259-278. (In Japanese with English abstract)
Ouchi, Y., 1978, Terrace Formation on the Eastern Coast of the Hidaka Region in Hokkaido. Annals of the Hokkaido GeographicalSociety, 52, 1-8. (In Japanese)
Ozawa, K., 2004. Thermal history of the Horoman peridotite complex: A record of thermal perturbation in the lithospheric mantle. Jour.
Petrol., 45, 253-273.
Takahashi, N., 1991, Origin of three peridotite suites from Horoman peridotite complex, Hokkaido, Japan: Melting, melt segregationand solidification processes in the upper mantle. J. Min. Petr. Econ. Geol., 86, 199-215.
Yoshikawa, M., Nakamura, E., 2000. Geochemical evolution of the Horoman peridotite complex: Implications for melt extraction,
metasomatism, and compositional layering in the mantle. JGR, 105, 2879-2901.
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Miyasaka, S., Tanaka, M., Oka, T., Okamura, S. and Nakagawa, M., 2011, Walking in the Nature of Sapporo 3rd Edition. Introduction to
the Geology of Central Hokkaido, Hokkaido University Press. (In Japanese)
Nakai, T., 1930, Vegetation of Mt.Apoi in the Province of Hidaka, Hokkaido, Survey Report on Natural Monuments of Japan, 12:1-80.
Ministry of Education, Science and Culture. (In Japanese)
Nihon Konbu Kyokai, 1986, Kelp – Nihon Konbu Kyokai 10th Anniversary Journal. (In Japanese)
Norishige Yotsukura et al.,2006, Nucleotide sequences diversity of the 5S rDNA spacer in the simpleblade kelp genera Laminaria,
Cymathaere and Kjellmaniella (Laminariales, Phaeophyceae) from northern Japan, Phycological Research, 54: 269-279 (2006)
Oishi, K., 1987, Kombu no michi. Daiichi Shobo Co., Ltd. (In Japanese)
Ono H, 1977, Prosimulium apoina n. sp. from Japan (Diptera, Simuliidae). Res. Bull. Obihiro Univ., 10: 749-757.
Sato, K., 2007, Geobotanical study on the alpine vegetation of Hokkaido, Japan, Hokkaido University Press. (In Japanese)
Takahashi, Y., 1973, Alpine Plants on Mt. Apoi. Samani Town Government. (In Japanese)
Takahashi, Y. and Tanaka, M., 2008, Alpine Plants and Grass on Mt. Apoi. Mt. Apoi Supporters’ Club. (In Japanese)
Tatewaki, M., 1927, The Vernal Vegetation in the Vicinity of cape Erimo and Mt.Apoi, Prov.Hidaka Hokkaido, Journal of the Sapporo
Society of Agriculture and Forestry, 85: 137-156. (In Japanese)
Tatewaki, M., 1928, The Vegetation of Mt. Apoi, Prov. Hidaka. Research Bulletins of the College Experiment Forests, College ofAgriculture, Hokkaido Imperial University, 5: 49-134. (In Japanese)
Tatewaki, M., 1952, Vegetation on Mt. Apoi and the Coastal Area. Survey Report 1 on the Vegetation of Areas under Management of the
Urakawa Forestry Office, Forests 5: 49-59. (In Japanese)
Watanabe, S., 2001, Decline of ultrabasicosaxicolous flora from 1954 to 1999 on Mt. Apoi, Hidaka Province, Hokkaido, Japan．Bulletinof Geo-environmental Science, Rissho University, 3: 25-48. (In Japanese)- 41 -

Appendix 1

List of Horoman Peridotite Publications

The Horoman peridotite complex has extremely high academic value. It is one of the world’s most studied peridotite masses, and thislist includes numerous related papers published in renowned international journals. The aims and details of research works on theperidotite complex are varied, and relate to of earth science. They include processes of magma movement in the upper mantle, origins of
the upper mantle’s compositional inhomogeneity, mechanisms behind melt generation and melt extraction, and solid-melt reactions
during melt segregation, ascent and transfer as well as the formation, modification and evolution of the initial mantle in the earth’s
history.
To clarify the trends and challenges of research on the Horoman peridotites, publications in this list are organized by theme under
the following nine headings:
1.
2.
3.
4.
5.
6.
7.
8.

Pioneer/comprehensive research on geology and petrology the Horoman peridotite complex as a whole
Examination of the petrological and mineralogical properties and origins of the Horoman peridotites
Elucidation of metasomatism (compositional modification during the island-arc stage) in the Horoman peridotites
Elucidation of symplectites (decompressional modification and the ascent processes) in the Horoman peridotites
Examination on geochemical properties and origins of the Horoman peridotites
Examination on evolutionary history of the Horoman peridotites based on isotope geochemistry and dating
Examination of compositional modification resulting from basaltic magma generation and melt migration, ascent and transportation
Analysis of textual patterns in the Horoman peridotites and their deformation and flow within the mantle
Regional geology, petrology, structures, tectonics and other aspects of the Hidaka Mountains, including the Horoman peridotite
complex

List of Horoman Peridotite Publications
1. Pioneer/comprehensive research on geology and petrology of the Horoman peridotite complex as a whole
Yamamoto, H., Nakamori, N., Terabayashi, M., Rehman, H.U., Ishikawa, M., Kaneko, Y., Matsui, T., 2010. Subhorizontal tectonic
framework of the Horoman peridotite complex and enveloping crustal rocks, south-central Hokkaido, Japan. Island Arc, 19,458-469.
Morishita, T., Ozawa, K. and Obata, M., 2010. A recent trend in sciences on mantlederived materials, with special emphases onrefertilization, rheology, and ophiolite problems: a report of the Fifth International Conference on Orogenic Lherzolite. Japanese
Magazine of Mineralogical and Petrological Sciences, 39, 85-103. (In Japanese with English abstract)
Niida, K., 2009, JGN’Mt. Apoi Geopark: Attractions for science, education, and geotourism. In: East Asian Geoparks-Vision, Problems
and Prospects, ed by Jiun-Chuan Lin. Geogr. Soc. China, 274-286.
Niida, K., Takazawa E., 2007. Origin of layering observed in the Horoman peridotite complex, Japan. Journal of Geological Society ofJapan, 113, Supplement 167-184. (In Japanese with English abstract)
Takahashi, Y., Niida, K., Sawaguchi, T. and Takahashi, N., 2002, Geoscience map of Mt. Apoi area at 1:50,000. Open file report of GSJ,
AIST, no. 376．
Niida, K., Takahashi, N., Takazawa, E., Sawaguchi, T., Morishita, T., Ozawa, K., Arai, S., and Obata, M., eds., 2002, Guide book forfield excursion to the Horoman peridotite complex. Field Guide, 4th International Workshop on Orogenic Lherzolite and Mantle
Processes. Samani, 1-98.
Obata, M., and Nishimoto, H., 1992, Whole-rock chemistry of the Horoman ultramafic rocks, Hokkaido, Japan. Kumamoto Jour. Sci., 13,
25-36.
Takahashi, N., 1991. Origin of three peridotite suites from Horoman peridotite complex, Hokkaido, Japan: Melting, melt segregationand solidification processes in the upper mantle. Journal of the Japanese Association of Mineralogists, Petrologists and Economic
Geologists, 86, 199-215.
Niida, K., 1984. Petrology of the Horoman ultramafic rocks in the Hidaka Metamorphic Belt, Hokkaido, Japan. Journal of the Facultyof Science, Hokkaido University. Series 4, Geology and mineralogy, 21, 197-250.
Niida, K., 1974, Structure of the Horoman ultramafic massif of the Hidaka metamorphic belt in Hokkaido, Japan. Jour. Geol. Soc. Japan,
80, 31-44.
Research Group of Peridotite Intrusion, 1967, Ultrabasic rocks in Japan. J. Geol. Soc. Japan, 73, 543-553.
Nagasaki, H., 1966, A layered ultrabasic complex in Japan. J. Fac. Sci., Tokyo Univ., Sec. 2, 16, 313-346.
Komatsu, M. and Nochi, M., 1966, Ultrabasic rocks in Hidaka metamorphic belt, Hokkaido, Japan. I. Mode of occurrence of the
Horoman ultlabasic rocks. Earth Science, 87, 21-29. (In Japanese with English abstract)
Onuki, H., 1965, Petrological research on the Horoman and Miyamori ultramafic intrusives, northern Japan. Sci. Rep., Tohoku Univ., 3rdSer., 9, 217-276.
Hunahashi, M., and lgi, S., 1956, Explanatory text of the geological map of Japan "Horoizumi" (scale 1: 50,000). Geol. Surv. Japan.,
64p. (In Japanese with English abstract)Igi, S., 1953, Petrographical studies on the peridotite in the Horoman region at the southern end of the Hidaka mountain range,- 42 -

Hokkaido. Jour. Geol. Soc. Japan, 59, 111-121. (In Japanese with English abstract)
2. Examination of petrological and mineralogical properties and origins of the Horoman peridotites
Kitakaze, A., Itho, H., Komatsu, R., 2011. Horomanite, (Fe, Ni, Co, Cu)9S8, and samaniite, Cu2(Fe,Ni)7S8, new mineral species from the
Horoman peridotite massif, Hokkaido, Japan. Journal of Mineralogical and Petrological Sciences, 106, 204-210.
Kitakaze, A., 2010. Sugakiite discovered as a new mineral species from the Horoman peridotite massif, Hokkaido, Japan. Japanese
Magazine of Mineralogical and Petrological Sciences, 39, 32-33. (In Japanese with English abstract)
Kitakaze, A., 2008. Sugakiite, Cu(Fe,Ni)8S8, a new mineral species from Hokkaido, Japan. Canadian Mineralogist, 46, 263-267.
Morishita, T., Arai, S., Ishida, Y., 2007. Occurrence and chemical composition of amphiboles and related minerals in corundum-bearing
mafic rock from the Horoman Peridotite Complex, Japan. Lithos, 95, 425-440.
Obata, M., Hirajima, T., Svojtka, M., 2007. Origin of eclogite and garnet pyroxenite from the Moldanubian Zone of the Bohemian
Massif, Czech Republic and its implication to other mafic layers embedded in orogenic peridotites. Mineralogy and Petrology, 88,
321-340.
Morishita, T., Takazawa, E., Arai, S., Obata, M., Kodear, T., Gervilla, F., 2006. Corundum-bearing mafic granulites in the Horoman(Japan) and Ronda (Spain) Peridotite Massifs: Possible remnants of recycled crustal materials in the mantle. Island Arc, 15, 2-3(pictorial).
Matsufuji, Y., Arai, S., Morishita, T., Ishida, Y., 2006. Petrology of exotic high-Mg, Cr peridotite bodies in the Horoman Peridotite
Complex, Japan. Japanese Magazine of Mineralogical and Petrological Sciences, 35, 231-243 (In Japanese with English abstract).
Ozawa, K., 2004. Thermal history of the Horoman peridotite complex: A record of thermal perturbation in the lithospheric mantle.
Journal of Petrology, 45, 253-273.
Morishita, T., Arai, S., Green, D.H., 2003. Evolution of low-Al orthopyroxene in the Horoman peridotite, Japan: An unusual indicator ofmetasomatizing fluids. Journal of Petrology, 44, 1237-1246.
Morishita, T., Arai, S., 2001. Petrogenesis of corundum-bearing mafic rock in the Horoman peridotite complex, Japan. Journal of
Petrology, 42, 1279-1299.
Morishita, T. and Kodera, T., 1998, Finding of corundum-bearing gabbro boulder possibly derived from the Horoman Peridotite
Complex, Hokkaido, northern Japan. Jour. Mineral. Petrol. Econ. Geol., 93: 52-63.
Morishita, T., 1998. Possible pseudotachylyte from the Horoman peridotite complex of the Hidaka belt, Hokkaido, northern Japan.
Journal of Geological Society of Japan, 104, 18-23.
Matsukage, K. and Arai, S. 1997, Ochiai-Hokubo peridotite and Horoman peridotite: a genetical comparison for insight into diverse
melting processes in the upper mantle. Mem. Geol. Soc. Japan, 47: 173-183. (In Japanese with English abstract)
Ozawa, K., 1997, P-T history of an ascending mantle peridotite constrained by Al zoning in orthopyroxene: a case study in the Horomanperidotite complex, Hokkaido, northern Japan. Mem. Geol. Soc. Japan, 47, 107-122.
Ozawa K., Takahashi, N., 1995. P-T history of a mantle diaper: the Horoman peridotite complex, Hokkaido, northern Japan.
Contributions to Mineralogy and Petrology, 120, 223-248.
Arai, S., and Takahashi, N., 1986, Petrographical notes on deep-seated and related rocks. (4) Highly refractory peridotites from
Horoman ultramafic complex, Hokkaido, Japan. Ann. Rep., Inst. Geosci., Univ. Tsukuba, 12, 76-78.
Arai, S., Hirai, H., 1985. Relics of H2O fluid inclusions in mantle-derived olivine. Nature, 318, 276-277.
Niida, K., 1977, Kaersutite, Ti-pargasite, and pargasite from gabbroic rock of the Horoman ultramafic massif, Japan. J. Japan. Assoc.
Min. Petr. Econ. Geol., 72, 152-161.
Tenpaku, T., 1967, On the plagioclase feldspar in the peridotite mass, in the Horoman Area, Hokkaido. Earth Science, 21: 10-13.
3. Elucidation of metasomatism (compositional modification during the island-arc stage) in the Horoman peridotites
Arai, S., Takahashi, N., 1989. Formation and compositional variation of phlogopites in the Horoman peridotite complex, Hokkaido,
northern Japan: implications for origin and fractionation of metasomatic fluids in the upper mantle. Contributions to Mineralogy
and Petrology, 101, 164-175.
Hirai, H. and Arai, S., 1987, H2O -CO2 fluids supplied in alpine-type mantle peridotites: electron petrology of relic fluid inclusions inolivines. Earth Planet. Sci. Lett., 85, 311-318.
Arai, S., 1986, K/Na variation in phlogopite and amphibole of upper mantle peridotites due to fractionation of the metasomatizing fluids.
Jour. Geol., 94, 436-444.
Arai, S., 1984, Pressure-temperature dependent compositional variation of phlogopitic micas in upper mantle peridotites. Contrib.
Mineral. Petrol., 87, 260-264.
Niida, K., 1975b, Phlogopite from the Horoman ultramafic rocks. Jour. Fac. Sci. Hokkaido Univ., Ser. IV, 16, 511-518.
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4. Elucidation of symplectites (decompressional modification and the ascent processes) in the Horoman peridotites
Odashima, N., Morishita, T., Ozawa, K., Nagahara, H., Tsuchiyama, A., Nagashima, R., 2008. Formation and deformation mechanismsof pyroxene-spinel symplectite in an ascending mantle, the Horoman peridotite complex, Japan: An EBSD (electron backscatter
diffraction) study. Journal of Mineralogy and Petrological Sciences, 103, 1-15.
Morishita, T., Arai, S., 2003. Evolution of spinel-pyroxene symplectite in spinel lherzolites from the Horoman Complex, Japan.
Contributions to Mineralogy and Petrology, 144, 509-522.
Morishita, T., 2000, Three-dimensional microstructure of symplectite minerals in the Horoman peridotite: a preliminary analysis. Jour.
Geol. Soc. Japan, 106, 800-811.
Morishita, T. and Arai, S., 1997, Diversity of occurrence of symplectite in the Horoman peridotite complex of the Hidaka belt, Hokkaido,
northern Japan, and its bearing on the P-T history. Memoirs of the Geological Society of Japan, 47, 149-162 (In Japanese withEnglish abstract).
Takahashi, N., and Arai, S., 1989, Textural and chemical features of chromian spinel-pyroxene symplectites in the Horoman peridotites,
Hokkaido, Japan. Sci. Rept., Inst. Geosci., Univ. Tsukuba, Sec. B, 10, 45-55.
Tazaki, K., Ito, E., and Komatsu, M., 1972, Experimental study on a pyroxene-spinel symplectite of high pressures and temperatures.
Jour. Geol. Soc. Japan, 78, 347-354.
5. Examination on geochemical properties and origins of the Horoman peridotites
Malaviarachchi, S.P.K., Makishima, A., Nakamura, E., 2010. Melt-Peridotite Reactions and Fluid Metasomatism in the Upper Mantle,
Revealed from the Geochemistry of Peridotite and Gabbro from the Horoman Peridotite Massif, Japan. Journal of Petrology, 51,
1417-1445.
Morishita, T., Arai, S., Green, D.H., 2004. Possible non-melted remnants of subducted lithosphere: Experimental and geochemical
evidence from corundum bearing mafic rocks in the Horoman peridotite complex, Japan. Journal of Petrology 45, 235-252.
Matsumoto, T., Chen, Y.L., Matsuda, J., 2001. Concomitant occurrence of primordial and recycled noble gases in the Earth’s mantle.
Earth and Planetary Science Letters, 185, 35-47.
Takazawa, E., Frey, F.A., Shimizu, N., Obata, M., 2000. Whole rock compositional variations in an upper mantle peridotite (Horoman,
Hokkaido, Japan): Are they consistent with a partial melting process? Geochimica et Cosmochimica Acta, 64, 695-716.
Yoshikawa, M., Nakamura, E., 2000. Geochemical evolution of the Horoman peridotite complex: Implications for melt extraction,
metasomatism, and compositional layering in the mantle. Journal of Geophysical Research, 105, 2879-2901.
Takazawa, E., Frey, F.A., Shimizu, N., Saal, A., Obata, M., 1999. Polybaric petrogenesis of mafic layers in the Horoman peridotite
complex, Japan. Journal of Petrology, 40, 1827-1851.
Rëhkamper, M., Halliday, A.N., Alt, J., Fitton, J.G., Sipfel, J., Takazawa, E., 1999. Non-chondritic platinum-group element ratios in
oceanic mantle lithosphere: petrogenetic signature of melt percolation? Earth and Planetary Science Letters, 172, 65-81.
Yoshida, H. and Takahashi, N., 1997, Chemical behavior of major and trace elements in the Horoman mantle diapir, Hidaka belt,
Hokkaido, Japan. J. Mineral. Petrol. Econ. Geol., 92, 391-409. (In Japanese with English abstract).
Takazawa, E., Frey, F.A., Shimizu, N., Obata, M., 1996. Evolution of the Horoman Peridotite (Hokkaido, Japan): Implications frompyroxene compositions. Chemical Geology, 134, 3-26.
Takazawa, E., Frey, F.A., Shimizu, N., Obata, M., Bodinier, J.-L., 1992. Geochemical Evidence for melt migration and reaction in theupper mantle. Nature, 359, 55-58.
Frey F. A., Shimizu N., Leinbach A., Obata M., and Takazawa E., 1991, Compositional variations within the Lower Layered Zone of the
Horoman peridotite, Hokkaido, Japan: Constraints on models for melt-solid segregation. In Orogenic Lherzolite and Mantle
Processes (ed. M. A. Menzies et al.); J. Petrol., Special Lherzolites Issue, 211-227.
6. Examination on evolutionary history of the Horoman peridotites based on isotope geochemistry and dating
Malaviarachchi, S.P.K., Makishima, A., Tanimoto, M., Kuritani, T., Nakamura, E., 2008. Highly unradiogenic lead isotope ratios fromthe Horoman peridotite in Japan. Nature Geoscience, 1, 859-863.
Weyer, S., Ionov, D.A., 2007. Partial melting and melt percolation in the mantle: The message from Fe isotopes. Earth and Planetary
Science Letters, 259, 119-133.
Saal, A.E., Takazawa, E., Frey, F.A., Shimizu, N., Hart, S.R., 2001. Re-Os isotopes in the Horoman peridotite: Evidence forrefertilization? Journal of Petrology, 42, 25-37.
Kaneoka, I., Takahashi, N., and Arai, S., 2001, 40Ar-39Ar analysis of phlogopite in the Horoman Peridotite Complex, Hokkaido, Japanand implications for its origin. Island Arc, 10, 22-32.
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Yoshikawa, M., Nakamura, E., 2000. Geochemical evolution of the Horoman peridotite complex: Implications for melt extraction,
metasomatism, and compositional layering in the mantle. Journal of Geophysical Research, 105, 2879-2901.
Yoshikawa, M., Nakamura, E., Takahashi, N., 1993. Rb-Sr isotope systematics in a phlogopite -bearing spinel lherzolite and its
implications for age and origin of metasomatism in the Horoman peridotite complex, Hokkaido, Japan. Journal of Mineralogy,
Petrology and Economic Geology, 88, 121-130.
7. Examination of compositional modification resulting from basaltic magma generation and melt migration, ascent andtransportation
Niida, K., Green, D. H., Yoshikawa, M., and Eggins, S. M., 2006, Dunite channels in the Horoman peridotites, Japan: Textural andgeochemical constraints on melt/fluid transport through the lithosphere. Geochim. Cosmochim. Acta, 70, 445.
Yoshikawa, M., Niida, K., Eggins, S. M., and Green, D. H., 2006, Trace element and isotopic (Sr and Nd) compositions ofclinopyroxenes in dunite channels of the Horoman peridotite complex, Hokkaido, Japan. Geochim. Cosmochim. Acta, 70, 724．
Obata, M., Takazawa, E., 2004. Compositional continuity and discontinuity in the Horoman peridotite, Japan, and its implication formelt extraction processes in partially molten upper mantle. Journal of Petrology, 45, 223-234.
Niida, K., 2001, Magma channeling systems in upper mantle peridotites: Observation and interpretation on dunite-chromitite channels.
In: Exploring the Earth: A Celebration of Four Journeys, RSES, ANU, 19-20.
Takahashi, N., 2001. Origin of plagioclase lherzolite from the Nikanbetsu Peridotite Complex, Hokkaido, Northern Japan: Implications
for incipient melt migration and segregation in the partially molten upper mantle. Journal of Petrology, 42, 39-54.
Takahashi, N., 1997, Incipient melting of mantle peridotites observed in the Horoman and Nikanbetsu peridotite complexes, Hokkaido,
northern Japan. Jour. Mineral. Petrol. Econ. Geol., 92, 1-24.
Shiotani, Y. and Niida, K., 1997, Origin of mafic layers in the Horoman peridotite complex. Mem. Geol. Soc. Japan, 47: 123-137. (InJapanese with English abstract)
Niida, K., and Shiotani, Y., 1997, Modes of magma channeling recorded in the Horoman peridotites: Replacive peridotites formed bymelt extraction and addition. Mem. Geol. Soc. Japan, 47: 139-147. (In Japanese with English abstract)
Takahashi, N., 1992. Evidence for melt segregation towards fractures in the Horoman mantle peridotite complex. Nature, 359, 52-55.
Obata, M., and Nagahara, N., 1987, Layering of Alpine-type peridotite and the segregation of partial melt in the upper mantle. Jour.
Geophys. Res., 92, 3467-3474.
8. Analysis of textural patterns in the Horoman peridotites and their deformation and flow within the mantle
Sawaguchi, T., 2004, Deformation history and exhumation process of the Horoman Peridotite Complex, Hokkaido, Japan.
Tectonophysics, 379, 109-126.
Sawaguchi, T. and Ishii, K., 2003, Three-dimensional numerical modeling of lattice and shape-preferred orientation of orthopyroxene
porphyroclasts in peridotites. Journal of Structural Geology, 25, 1425-1444.
Ishii, K., Sawaguchi, T., 2002. Lattice- and shape-preferred orientation of orthopyroxene porphyroclasts in peridotites: an application of
two-dimensional numerical modeling. Journal of Structural Geology 24, 517-530.
Sawaguchi, T., Goto, K., Takagi, H., 2001. Elongated orthopyroxene porphyroclasts as a shear sense indicator and kinematic history of
the Horoman Peridotite Complex, Hokkaido, Japan. Journal of Geological Society of Japan, 107, 165-178.
Toramaru, A., Takazawa, E., Morishita, T., Matsukage, K., 2001. Model of layering formation in a mantle peridotite (Horoman,
Hokkaido, Japan). Earth and Planetary Science Letters, 185, 299-313.
Takizawa, S., 1997, Flow fold of the Horoman peridotite complex, Hokkaido, Japan. Mem. Geol. Soc. Japan, 47: 209-218. (In Japanesewith English abstract)
Toramaru, A., 1997, Origin of layered structure of the Horoman ultramafic complex. Mem. Geol. Soc. Japan, 47: 185-192.
Sawaguchi, T. and Takagi, H., 1997, Inverted ductile shear movement of the Horoman peridotite complex in the Hidaka metamorphic
belt, Hokkaido, Japan. Mem. Geol. Soc. Japan, 47, 107-122.
Niida, K., 1975a, Textures and olivine fabrics of the Horoman ultramafic rocks, Japan. J. Japan Assoc. Min. Petr. Econ. Geol., 70,
265-285.
9. Regional geology, petrology, structures, tectonics and other aspects of the Hidaka Mountains, including the Horomanperidotite complex
Kita, S., Okada, T., Hasegawa, A., Nakajima, J., Matsuzawa, T., 2010. Anomalous deepening of a seismic belt in the upper-plane of the
double seismic zone in the Pacific slab beneath the Hokkaido corner: Possible evidence for thermal shielding caused by subducted
forearc crust materials. Earth and Planetary Science Letters, 290, 415-426.
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Kemp, A.I.S., Shimura, T., Hawkesworth, C.J., EIMF, 2007. Linking granulites, silicic magmatism, and crustal growth in arcs: ion
microprobe (zircon) U-Pb ages from the Hidaka metamorphic belt, Japan. Geology, 35, 807-810.
Gorczyk, W., Gerya, T.V., Connolly, J.A.D., 2007. Growth and mixing dynamics of mantle wedge plumes. Geology, 35, 587-590.
Niida, K., 2004, Hidaka Mountains: Rocks generated in deep lithosphere beneath the island-arc. In: Earth Science of ‘THE ISLAND
ARC’, The Hokkaido University Museum. 26-32.
Arita, K., Maeda, J., and Niida, K., 2003: Deep-seated plutonic and metamorphic rocks of the Hidaka mountains, Hokkaido. In: Field
Trip Guidebook, IUGG 2003: C2. Volc. Soc. Japan, 265-308.
Yamamoto, A., Yamada, K., Saito, M., Ishikawa, H., 2001. Gravity anomaly around the Horoman Peridotite Region, central Hokkaido,
Japan. Geophysical Bulletin of Hokkaido University, 64, 51-80 (In Japanese with English abstract).
Arita, K., Ikawa, T., Ito, T., Yamamoto, A., Saito, M., Nishida, Y., Satoh, H., Kimura, G., Watanabe, T., Ikawa, T., Kuroda, T., 1998.
Crustal structure and tectonics of the Hidaka Collision Zone, Hokkaido (Japan), revealed by vibroseis seismic reflection andgravity surveys. Tectonophysics, 290, 197-210.
Maeda, J., Kagami, H., 1997, Interaction of a spreading ridge and an accretionary prism: implications from MORB magmatism in the
Hidaka magmatic zone, Hokkaido, Japan. Geology, 21, 31-34.
Saeki, K., Shiba, M., Itaya, T., 1995. K-Ar ages of the metamorphic and plutonic rocks in the southern part of the Hidaka belt, Hokkaido
and their implications. Journal of Mineralogy, Petrology and Economic Geology, 88, 101-113.
Tagiri, M., Tanaka, H., and Shiba, M., 1995, Melting of amphibolites and the form of melt-trap in amphibolite-migmatites of thesouthern Hidaka metamorphic belt, Hokkaido, Japan. J. Min. Petrol. Econ. Geol., 90, 50-63.
Maeda, J., and Kagami, H., 1994, Mafic igneous rocks derived from N-MORB source mantle, Hidaka magmatic zone, Central
Hokkaido: Sr and Nd isotopic evidence. J. Geol. Soc. Japan, 100, 185-188.
Komatsu, M., Toyoshima, T., Osanai, Y., Arai, M., 1994. Prograde and anatectic reactions in the deep arc crust exposed in the Hidaka
metamorphic belt, Hokkaido, Japan. Lithos, 33, 31-49.
Osanai, Y., Komatsu, M., Owada, M., 1991, Metamorphism and granite genesis in the Hidaka metamorphic belt, Hokkaido, Japan. J.
Metamorphic Geol., 9, 111-124.
Miyamachi, H. and Moriya, T., 1984, Velocity structure beneath the Hidaka Mountains in Hokkaido, Japan. Jour. Phys. Earth, 32:
13-42.
Komatsu, M., Miyashita, S., Maeda, J., Osanai, Y., Toyoshima, T., 1983, Disclosing of a deepest section of continental-type crust
upthrust as the final event of collision of arcs in Hokkaido, North Japan. In: Hashimoto, M., and Uyeda, S. (eds.); Accretion
tectonics in the Circum-Pacific regions, TERRAPUB, Tokyo, 149-165.
Niida, K. and Katoh, T. 1978, Ultramafic rocks in Hokkaido. Monogr. Assoc. Geol. Collabo. Japan, 21: 61-81. (In Japanese withEnglish abstract)
Komatsu, M., 1975, Recrystallization of the high-alumina pyroxene peridotite of the Uenzaru area in Hidaka province, Hokkaido, Japan.
J. Geol. Soc. Japan, 81, 11-28.

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- 47 -

Mt. Apoi

Lherzolite
Harzburgite
Plagioclaselherzolite

Precambrian–

Precambrian–

Precambrian–

Precambrian–River beach near thequarryJapanese White Pine
Monument

Fudo-no-sawa

Dam of Power
Station No. 2

Horoman-gawa Inari
ShrineHoroman Dam (damof Power Station No.
3)

A2

A3

A4

A5

A6

A7

SpecialProtection Zone
SpecialProtection Zone

Top of Mt. Apoi
Ridge landform in the southern part of
the Hidaka Mountains

Precambrian–

Umanose flower
fields

Mt. Apoi

Horoman flower
fieldsApoi to Yoshida

Mt. Yoshida

Pinneshiri

B6

B7

B8

B9

B10

Plagioclaselherzolite
Mafic rock Type
GB I
Plagioclaselherzolite
Plagioclaselherzolite

Precambrian–

Precambrian–

Precambrian–

Peridotite

SpecialProtection Zone

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: uppermost
zone
Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: northernhalfSpecialProtection Zone

SpecialProtection Zone

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: upper zone

SpecialProtection Zone

SpecialProtection Zone

B5

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: magmachannelHoroman Peridotite Complex in the
Hidaka Metamorphic Belt: peridotite
massifPrecambrian–

Sixth to seventhstagesB4High-Mg peridotite
Mafic rock Types
GB I/II/IV

SpecialProtection Zone

Precambrian–

Fifth-stage mountain
lodge

B3

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: upper zone

Class IIISpecial Zone

Alpine Plant
Regeneration Test
Site

B2
Plagioclaselherzolite

Class IIISpecial Zone

Rest Spot No. 4

Class IIISpecial Zone

B1

Hidaka Metamorphic Belt:
lower to middle parts of the Middle
Zone

Gneiss, amphibolite
Gabbro, tonalite

Paleogene –NeogeneClass IIISpecial Zone

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: lowpressure type, gorge, potholes

Plagioclaselherzolite
Mafic rock TypeGB I

Precambrian–Class IIISpecial Zone

Quasi-nationalpark area

Class IIISpecial Zone

Research

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: contactrelated magma channel, gorge

Tourism

DuniteHarzburgite

Education

Class IIISpecial Zone

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: lowermost
zone, gorge
Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: gorge,boulders
Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: highpressure type, gorge

Geological/topographical features

Mt. Apoi Geopark Geosite List

Horoman Peridotite Complex in the
Hidaka Metamorphic Belt: gorge

Peridotite, gabbro

Harzburgite –Lherzolite

Precambrian–Power Station No. 2

A1

Horomankyo

Rock types

Geosite

Era

No.

Area

Appendix 2
Information
board

Special Natural Monument ofJapan, Japan's Top 100
Geological Features
Special Natural Monument ofJapan, Japan's Top 100
Geological Features

Special Natural Monument ofJapan, Japan's Top 100
Geological Features

Special Natural Monument ofJapan, Japan's Top 100
Geological Features
Special Natural Monument ofJapan, Japan's Top 100
Geological Features
Special Natural Monument ofJapan, Japan's Top 100
Geological Features
Special Natural Monument ofJapan, Japan's Top 100
Geological Features
Special Natural Monument ofJapan, Japan's Top 100
Geological Features

Natural Monument of Japan

Remarks

- 48 -

Tojuin Temple

Byobu Cliff in Hirau

C5

C6

Shintomi

HidakaYabakeiMt. Kannon

C4

NeogeneCretaceous

Paleogene

Paleogene –NeogeneFault at the Higashi
Fuyushima Tunnel

Metagabbro at the
Kotoni Tunnel

Granite at the Taisho
TunnelGeological fold at
the Ruranbetsu
TunnelSamani Mountain
Path and Wasuke
Jizo

D2

D3

D4

Limestone,
mudstone, sandstone

Triassic
Cretaceous –Paleogene

Limestone blocks in
Matsuokazawa

E4

Idonnappu Belt, accretionary prism
mélange

Idonnappu Belt, accretionary prism
mélange

Chert

Jurassic
Cretaceous –PaleogeneChert in Shintomi

E3

Idonnappu Belt, accretionary prism
mélange

Sandstone,
mudstone

Cretaceous –Paleogene

Lenticular sandstone
at the Samani Dam

E2

Idonnappu Belt, accretionary prism
mélange

Class II Special
Zone

Hidaka Metamorphic Belt:
lower part of the Middle Zone, sea cliff

Amphibolite, biotite
gneissClass II Special
Zone

Ordinary area

Quasi-nationalpark area

Class II Special
Zone

Research

Hidaka Metamorphic Belt:
lower part of the Middle Zone

Tourism

GraniteEducation

Class II Special
Zone

Hidaka Main Thrust (HMT)
Former plate boundary

Idonnappu Belt:
Fuyushima metamorphic rocks, sea
cave

Cretaceous (Yezo Group) fore-arc basin
area

Shallow sea sediment containing shellfossils

Dike intruding into the Cretaceous
System (Yezo Group), erosion

Dike intruding into the Cretaceous
System (Yezo Group), peridotite massif

Dike intruding into the Cretaceous
System (Yezo Group)

Dike intruding into the Cretaceous
System (Yezo Group)

Geological/topographical features

Poroshiri Ophiolite Belt

MetagabbroBlack mudstone,
serpentinite,metagabbro

Hornfels

Sandstone,
mudstone

Conglomerate,
sandstone, mudstone

Porphyrite

Porphyrite

Porphyrite

Porphyrite

Rock types

Limestone,
mudstone, sandstone

Triassic
Cretaceous –Paleogene

Old mine of Ono
Kogyo Co., Ltd.

E1

D6

D5

Paleogene

Cretaceous

NeogeneNeogeneAna-iwa inFuyushima

D1

C8

Old quarry behind
Samani Elementary
SchoolOkada District cise(traditional Ainu
dwelling)

Cape Enrumu

C3

C7

NeogeneOyako-iwa andSobira-iwa

C2

NeogeneNeogeneShiogama Tunnel
and Rosoku-iwa

C1

Era

Samani
Coast

GeositeNo.

Area

Information
board

Municipal cultural property

Hokkaido Remarkable
Geosites 100

Hokkaido Remarkable
Geosites 100

Hokkaido Remarkable
Geosites 100

Municipal cultural property

Municipal place of scenic
beautyMunicipal place of scenic
beauty, Hokkaido Remarkable
Geosites 100
Municipal place of scenic
beautyMunicipal place of scenic
beautyRemarks