Contents
A. Identification of the Area ........................................................................................................................................................... 1
A.1 Name of the Proposed Geopark ........................................................................................................................................... 1
A.2 Location of the Proposed Geopark ....................................................................................................................................... 1
A.3 Surface Area, Physical and Human Geographical Characteristics ....................................................................................... 1
A.3.1 Physical Geographical Characteristics .......................................................................................................................... 1
A.3.2 Human Geographical Charactersitics ........................................................................................................................... 3
A.4 Organization in charge and Management Structure ............................................................................................................. 5
A.4.1 Izu Peninsula Geopark Promotion Council ................................................................................................................... 5
A.4.2 Structure of the Management Organization .................................................................................................................. 6
A.4.3 Supporting Units/ Members .......................................................................................................................................... 7
A.4.4 Finances ........................................................................................................................................................................ 7
A.5 Application contact person ................................................................................................................................................... 7
B. Geological Heritage ................................................................................................................................................................... 8
B.1 General geological description of the proposed Geopark .................................................................................................... 8
B.2 Listing and description of geological sites within the proposed Geopark .......................................................................... 13
B.3 Details on the interest of these sites in terms of their international, national, regional or local value................................ 20
B.4 Listing and description of other sites of natural, cultural and intangible heritage interest and how they are related to thegeological sites and how they are integrated into the proposed Geopark.................................................................................. 29
C. GEOCONSERVATION ............................................................................................................................................................ 32
C.1 Current and Potential Pressure on the proposed Geopark .................................................................................................. 32
C.2 Curent status in terms of protection of geological sites wothin the proposed Geopark ..................................................... 32
C.3 Data on the management and maintenance of all heritage sites ......................................................................................... 33
C.3.1 The Management of heritage sites .............................................................................................................................. 33
C.3.2 The Conservation and Preservation Management of Geosites ................................................................................... 34
D. Economic Activity and Business Plan...................................................................................................................................... 36
D.1 Economic activity in the proposed Geopark ...................................................................................................................... 36
D.1.1 Characteristics of Local Industries ............................................................................................................................. 36
D.1.2 Tourism ....................................................................................................................................................................... 37
D.1.3 Agriculture, Forestry, and Animal Husbandry ............................................................................................................ 37
D.1.4 Fisheries ..................................................................................................................................................................... 38
D.2 Existing and Planned Facilities in the proposed Geopark .................................................................................................. 38
D.2.1 Central Facility ........................................................................................................................................................... 38
D.2.2 Provision of Visitor Centers ....................................................................................................................................... 39
D.2.3 Guidance and Interpretation Panels ............................................................................................................................ 39
D.3 Analysis of geotourism potential of proposed Geopark ..................................................................................................... 40
D.3.1 Geotourism Strengths ................................................................................................................................................. 40
D.3.2 Geotourism Weaknesses ............................................................................................................................................. 40
D.3.3 Ongoing Activities and Future Vision ........................................................................................................................ 41
D.4 Overview and policies for the sustainable development .................................................................................................... 42
D.4.1 Geotourism and Economy .......................................................................................................................................... 42
D.4.2 Geo-education ............................................................................................................................................................ 43
D.4.3 Geo-heritage ............................................................................................................................................................... 44
D.5 Policies for community empowerment in the proposed Geopark ...................................................................................... 45
D.6 Policies for public and stakeholder awareness in the proposed Geopark ........................................................................... 45
E. Reasons for Seeking Recognition as a UNESCO Global Geopark........................................................................................... 47

A. Identification of the Area
A.1 Name of the Proposed Geopark
The name of the proposed Geopark is the “Izu Peninsula Geopark”.
The Izu peninsula is blessed with a rich natural environment, where history, culture, and cuisine have grown and flourished. As
one of the most famous regions in Japan for hot springs, it has long welcomed many visitors. Much of this natural and social
environment is closely entwined with the creation of the peninsula and its current geology.

A.2 Location of the Proposed Geopark
fig. 1 shows the location of the Izu Peninsula Geopark. It extends from 34°32′42.4″ to 35°13′16.3″ North, and from 138°42′18″ to139°12′32.4″ East. It is 100 km WSW of Tokyo, the capital of Japan, and by train is about 40 minutes from Tokyo, and 1 hourfrom Tokyo International Airport. In order to make area including all terrestrial areas where resident exists, Geopark area is set
also in the sea area (3km from the coastline). And, the boundary on the north side is in agreement with the administrative

Hatsushima Island

Narita Airport

Tokyo
Haneda Airport

Shizuoka Pref.

Izu
Peninsulaboundaries.
fig. 1 Location of the Proposed Geopark

A.3 Surface Area, Physical and Human Geographical Characteristics
The proposed Geopark covers the whole area of the Izu Peninsula, 2,027 km2 (land area: 1585 km2). This covers the area incommon between the geophysical “Izu”, which was carried from the south by the motion of Philippine Sea plate and collided
with Honshu(Japan main island) , and the cultural and tourist “Izu”, the old “Izu-no-Kuni”.
There are 15 administrative units within the Geopark :Tokyo
Numazu City, Atami City, Mishima City, Ito City, Shimoda
Mt.Fuji
City, Izu City, Izunokuni City, Higashiizu Town, Kawazu
Town, Minamiizu Town, Matsuzaki Town, Nishiizu Town,
Kannami Town, Shimizu Town, and Nagaizumi Town.
Izu
Peninsula

A.3.1 Physical Geographical Characteristics
Nagoya[Topography/Relief]
The Izu peninsula is a peninsular landmass that extends about
60 km southward at the eastern edge of Shizuoka Prefecture: it
has a maximum east-west width of 40 km, and a total coastal
length of 318 km. Most of the area, apart from the Tagata plain
1

fig. 2 Topography

in the north, is covered by mountains of low to moderate elevations. The highest point of the peninsula is Mt. Banzaburo (1405 m
asl) in the Amagi Range. The protrusion of these mountains over the sea causes heavy rain to fall in some regions of the peninsula,and also creates a diverse coastal topography. This complex landscape also forms natural barriers between localities within thepeninsula, and creates scenic diversity between and within areas.
Sagami bay, located to the east of the peninsula, has a depth of 1000m off the shore of Hatsushima Island and 1500m in the bay
off the south shore of Ōshima Island. Suruga bay in the west is still deeper, 2500m in the baymouth between Irozaki andOmaezaki. These deep bays are influenced by water coming in from outlying oceanic systems. The Kuroshio current, flowing
along the south of the Japanese archipelago, is impeded by the volcanic rise to the south of the Izu peninsula and changes its
path to flow into the bays. Cold seawater originating from large scale circulation off Greenland flows beneath the warmer
Kuroshio. Fig. 2 shows the topographical characteristics of and around the Geopark.
The Kanogawa river (length 46 km) is the longest river of the peninsula. It is one of the few rivers that flows northward into the
Pacific Ocean (Suruga bay). In the lower parts of the Kano plain, the width of the river narrows due to the inflow of volcanic
ejecta and debris flow, and it tends to flood during heavy rain and typhoons. The peninsula has no large river systems apartfrom the Kanogawa river, and therefore sediment inflow into the surrounding sea is negligible. The deep waters near the coastand different temperature ranges and water qualities in the bays make these water bodies rich fishing grounds.

[Climate]
According to the Köppen-Geiger classification, theIzu peninsula is located in the temperate humid
climate zone, as with most locations in Japan.
However, the climate within the peninsula varies
appreciably between the coastal and interior parts.
The coastal regions are influenced by the warm
Kuroshio current and have a mean annual
temperature of 15–17 ºC; the southern tip ofIrozaki Cape does not receive any snowfall even in
the winter. In contrast the northern Tagata plain has
Source: Japan Meteorological Agency
fig. 3 Annual Temperature
a wide difference between day and nighttemperatures, and winter in this area is noticeably colder. The central Amagi highland receives a flow of humid air from the
Pacific, resulting in high levels of precipitation (over 4000 mm/year at Mt Amagi) and frequent snowfall during winter. On theother hand the western part of the peninsula is relatively dry due to the prevailing winds depositing their moisture content over thecentral highlands. Compared to the Tokyo metropolitan area, the coastal areas are warm in winter and cool in summer.
[Ecosystems and Biodiversity]
The climatic diversity of the peninsula directly contributes to its biodiversity. The Amagi highlands, with multiple prominent
peaks such as Banjiro and Banzaburo-dake, is known for its forests of deciduous broadleaf trees: Fagus crenata (Buna orJapanese Beech), Stia monadelpha (Himeshara) and Aceraceae family. In particular, it is unusual to find a Fagus crenata foreston the Pacific coast. A 2.2 km2 tract of old-growth forest is located in Kannami Town, on the slopes of the Quaternary volcanic
mountains (500–850 m asl of elevation) that rise at the east of the Tagata plain. Broadleaf trees such as 700 year old giant Fagus
crenata, as well as gigantic Quercus acuta (Akagashi), and Stewartia monadelpha are found there. This tract of forest is known
for its contribution to the watershed, and has been preserved for this purpose since the Edo Period (1603–1868).
In the northwestern part of the peninsula, a curious sand spit formation in the Osezaki area allows a large group of very old juniper
trees to thrive. These junipers mark the northernmost extension of the natural range of juniper in the Japanese archipelago, andsome of the giant trees are estimated to be nearly a thousand years old. The Osezaki Juniper Colony is registered as a National
Natural Monument.

Osezaki Juniper

Amagi beech

2

Pennant coralfish

A diverse range of marine organisms, mostly native to a warm marine environment, can be found in the sea around thepeninsula. In the past, new marine species like Bodianus masudai (Shimakitsunebera) were discovered off the coast of the Izu
peninsula, and marine species previously unknown in Japan continue to be discovered from the depths of the seas around this
proposed Geopark. In addition some marine species such as Pseudanthias leucozonus (Shiroobihanadai) and Pseudotrichonotus
altivelis (Hotate’eso) are only found off the coasts of Izu, and they are therefore endemic to the region. The Uchiura bay ishome to the Acropora reef building coral family (Acropora tumida, Japanese name Edamidoriishi), and this location is thenorthernmost limit of Acropora’s range around the Japanese archipelago. Several deep sea species such as Regalecus russelii(Ryūgūnotsukai), Diaphus watasei (Hadakaiwashi lanternfish), Chiroteuthis imperator (Yūreiika or phantom squid), Paralomis
dofleini (Tsubuezoibaragani) as well as the Japanese Spider Crab (Macrocheira kaempferi) have their habitats in the deep
waters around the peninsula. The Japanese Spider Crab, or Takaashigani, is the largest crab species in the world, and it lives inthe deep Suruga bay to the west of Izu. Seaweed beds are widespread along most coastal areas: the rocky coastal areas are
known for Sargassum and Gelidium seaweed, while sandy beaches are known for Zostera (sea grass). Vegetation such as
Ecklonia is the food for the Abalone (Awabi), Turban shell (Sazae) and Sea Urchin (Uni).

A.3.2 Human Geographical Charactersitics【Population】
The total population of the proposed Geopark area is669,585 (2015 census), comprising 278,158 households.
Because mountains and highlands predominate, thepopulation is mostly concentrated in the coastal andnarrow plain regions. 62% of the total population isconcentrated in the 5 administrative units (Numazu City,
Mishima City, Kannami Town, Shimizu Town andNagaizumi Town) around the Tagata plain.
【Historical and Cultural Backgrounds】
Human occuptaion of the peninsula goes back around
30,000 years. This was the latter part of the Paleolithic
era in Japan. The discovery of varied remains in the
Ashitaka mountains and western parts of the lower
Hakone mountain area testifies to the existence ofsizable populations at this period. Later, Izu became astrategic location for marine traffic. The evidence
comes from the discovery of obsidian from Kozushimaisland in the Mitakadanma ruins in Kawazu Town; thisshows that this place was a storage point for obsidianthat entered Izu from outside.
Artifacts from the Yayoi Era (300 BC–250 AD), when
wet rice cultivation became widespread throughout
Japan, are found in the southern part of the peninsula.
The Hizume ruins of Minamiizu Town, Himemiya ruinsof Kawazu Town, and Ebisujima ruins of Shimoda City
are valuable evidence for the history of this period,
when the coastal areas in the south of the peninsula
were developed due to the lack of flat land.
Notable ruins of the Kofun Era (250 AD–600AD)
include the Mukaiyama, Kashiya, and Ema burial
mounds. The Mukaiyama mounds are the first keyhole
Kofun burial mounds found in Izu, while the mounds in
Kashiya park are accessible to tourists. The Jo-ri-sei

Topography of the Izu Peninsula3

primitive land grid system was developed in the Asuka Period (592–710 AD) and this formed the basis of the development ofcropland and roadways in the Tagata plain.
Izu has been the site of important turning points in history. Minamoto no Yoritomo (A.D. 1147 – 1199. The founder and the first
shogun of the Kamakura Shogunate of Japan.) was exiled to Izu after the Heiji Rebellion of 1160, and raised the banner ofKashiya tunnel-tombs

Ebisujima Ritual Ruins

Nirayama Reverberatory Furnaces（Part of World Heritage）

rebellion there in the battles that led to the creation of the Kamakura bakufu. In the mid-19th century, Shimoda was the site of theagreement of treaties to open Japan to trade. Designated National Historic Sites include Hirugakojima, where Minamoto no
Yoritomo is said to have spent 20 years of exile, Ganjojuin, where his wife Hojo Masako was born, the Nirayama Reverberatory
Furnaces, which was built by Hidetatsu Egawa in the mid-19th century in an attempt to construct large guns, and which survives
almost intact, and Gyokusenji, which was the first US consulate in Japan. The Nirayama Reverberatory Furnaces is part of the“Sites of Japan’s Meiji Industrial Revolution: Iron and Steel, Shipbuilding and Coal Mining” World Heritage Site.

[Use of Stone and Minerals]
The old stone quarries of Izu peninsula are a major cultural attraction of the area. ‘Izu Stone’ is a special stone quarried in Izu, andit was prized as a building material in pre-modern Japan. There are two types of Izu Stone: ‘hard’ and ‘soft.’ The hard stones are
generally andesitic stones that have excellent heat and trauma resistance properties; these were used as materials for castle wallsin Edo castle and Sunpu castle. The soft stones are generally softer and lighter volcanic ash, and were perfect materials to build
kilns or storehouses. These stones were also prized for their ornamental value.
The Usami Quarry in Ito, which supplied hard Izu Stone in the past, was registered as a historic site in 2011.
Izu Soft Stone was used throughout the Kanto region of Japan (the area around Tokyo in east central Japan), due to both the factthat these stones are easy to process, and to the historical importance of Izu as a marine trade point. Later, after the Kanto
earthquake (1923) and the development of overland routes, Oya stone from Tochigi replaced soft Izu Stone as the dominantquarried stone in Japan. Soft stone from Izu can still be seen in the baths and floors of many Japanese households, and in the wallsof many historical buildings and storehouses in Shimoda City.
In addition, minerals such as gold were extracted in large quantities from Izu’s mines in premodern times. Gold mining in Izu
rivaled the Tohoku region in the middle ages, and mines such as the Toi and Gantsuki Tensho goldmines were prominent. These
two goldmines are registered as historic sites by their local authorities.

Quarry Used for Edo Castle

Shimoda StreetscapeGantsuki Tensho goldmine[Beliefs and Festivals]
92 shrines from Izu are registered in the 10th-century Engishiki register ofshrines. This number is higher than other regions of Shizuoka Prefecture. Izu
has witnessed frequent natural disasters such as earthquakes, volcanism andtsunami since ancient times. These events directly contributed to local beliefs,
as local communities began to worship the deities who were supposed to ruleover natural forces. Many shrines were thus built in this region as places forworshipping such deities.
Mishima Taisha Shrine

4Mishima Taisha Shrine is the most important Shinto shrine in the Izu peninsula. The presiding deity, or kami, is Mishima
Daimyojin, a kami of fire. Whenever there was an eruption on the Miyakejima or Kozushima volcanic islands off Izu, the rank ofMishima Daimyojin was raised. The main sanctuary is a National Important Cultural Property. The legend of Mishima Daimyojin
says that the deity arrived in Mishima after initially lodging at Shirahama Jinja Shrine in Shimoda. Shirahama Jinja is the oldest
shrine in the Izu peninsula, and the shrine continues to worship the kami of the turbulent Izu islands through a fire ritual known as
the Hitachisai festival.
In addition there are many shrines such as Iro Jinja Shrine at the tip of southern Izu where people worship the kami of the seas andpray for safe voyages.

Iro Jinja Shrine

Kawakanjo (Prayer for the safety of Kanogawa River)[Writers and Izu]
Izu is a famous hot spring destination, and many famous writers frequented this area. Yasunari Kawabata, who received the Nobel
Prize in Literature in 1968, set his novel The Dancing Girl of Izu in the Izu peninsula. Another famous novel is Shirobamba,
written by Yasushi Inoue, set in the Amagi Yugashima area. Other notable authors who wrote stories set in the area include Osamu
Dazai and Banana Yoshimoto. There are many inns, spring baths and other buildings in Izu that were visited by literary
luminaries.

A.4 Organization in charge and Management Structure
A.4.1 Izu Peninsula Geopark Promotion Council
The Izu Peninsula Geopark Promotion Council is the body responsible for managing the Geopark. It is composed of 72 bodies,including local authorities, transport companies, and local media organizations. The members are listed following table.
【Local Government】Shizuoka Prefecture, Numazu City, Atami City, Mishima City, Ito City, Shimoda City, Izu City, Izunokuni City,
Higashiizu Town, Kawazu Town, Minamiizu Town, Matsuzaki Town, Nishiizu Town, Kannami Town, Nagaizumi Town, Shimizu Town
【Regular Members】16 Tourist Associations (Numazu, Heda, Atami, Mishima, Ito, Shimoda, Izu, Izunokuni, Higashiizu town, Kawazu
town, Minamiizu town, Matsuzaki town, Nishiizu town, Kannami town, Shimizu town, Nagaizumi town),
5 Chambers of Commerce and Industry (Numazu, Atami, Mishima, Ito, Shimoda)
11 Societies of Commerce and Industry (Numazu, Izu, Izunokuni, Higashiizu town, Kawazu town, Minamiizu town, Matsuzaki town,
Nishiizu town, Kannami town, Shimizu town, Nagaizumi town)
3 Guide Clubs (Amagi Nature Guide Club, Izu Peninsula Geoguide Association, Ito Geo marine Club)NPO Machikon ITO, Shizuoka Prefectural Izu Sogo High School, Mishima Building Contractors Society, Shimoda Building Contractors
Society,
Izukyu Holdings Co.Ltd., Izuhakone Railway Co.Ltd., Izuhakone Bus Co.Ltd., Tokai Jidosha Co.Ltd., Shizuoka Taxi Association Izu
Section, Izubus Co.Ltd., S-pulse Dream Ferry Co.Ltd., Shizuoka Road Public Corp.,
Shizuoka Bank Ltd., Mishima Shinkin Bank, Numazu Shinkin Bank, Izukyu Cable Network Co.Ltd.,【Research Institution】Shizuoka University Center for Integrated Research and Education of Natural Hazards【National Ministries and Offices】MLIT. Numazu Office of River and National Highway, MLIT. JMA. Shizuoka Meteorological Office,
MAFF. Forestry Agency Izu Office, MoE. Hakone Environmental Office
MoE: Ministry of the Environment, MLIT: Ministry of Land, Infrastructure, Transport and Tourism JMA: Japan Meteorological
Agency, MAFF: The Ministry of Agriculture, Forestry and Fisheries of Japan
Local Government】Shizuoka Prefecture, Numazu City, Atami City, Mishima City, Ito City, Shimoda City, Izu City, Izunokuni City,
Higashiizu Town, Kawazu Town, Minamiizu Town, Matsuzaki Town, Nishiizu Town, Kannami Town, Nagaizumi Town, Shimizu Town
【Regular Members】16 Tourist Associations (Numazu, Heda, Atami, Mishima, Ito, Shimoda, Izu, Izunokuni, Higashiizu town, Kawazu
town, Minamiizu town, Matsuzaki town, Nishiizu town, Kannami town, Shimizu town, Nagaizumi town),
5 Chamber of Commerce and Industry (Numazu, Atami, Mishima, Ito, Shimoda)
11 Society of Commerce and Industry (Numazu, Izu, Izunokuni, Higashiizu town, Kawazu town, Minamiizu town, Matsuzaki town,
Nishiizu town, Kannami town, Shimizu town, Nagaizumi town)
5
3 Guide Club (Amagi Nature Guide Club, Izu Peninsula Geoguide Association, Ito Geo marine Club)NPO Machikon ITO, Shizuoka Prefectural Izu Sogo High School, Mishima Building Contractors Society, Shimoda Building Contractors
Society,
Izukyu Holdings Co.Ltd., Izuhakone Railway Co.Ltd., Izuhakone Bus Co.Ltd., Tokai Jidosha Co.Ltd., Shizuoka Taxi Association Izu

A.4.2 Structure of the Management Organization
The Izu Peninsula Geopark Promotion Council is composed of a General Assembly, an Executive Committee, the Promotion
Council Bureau, and a number of Working committees. The General Assembly is made up of representatives of all the member
organizations, and meets once a year to set regulations, strategy, and budget, and to discuss other important issues. The
Executive Committee investigates issues to be submitted to the General Assembly, and is responsible for putting plans into
effect. The Promotion Council Bureau carries out day-to-day work on the ground and serves as a contact point for the Geopark.
The Working committees provide specialist support, and at present there are four: Geoconservation, Geotourism, Education,
and Academic Research.
The Promotion Council Bureau is located in the Shuzenji area of Izu City, near the entrance to the peninsula, and currently has
11 staff. The Bureau employs a specialist geologist, in earth sciences and disaster mitigation. His responsibilities include
carrying out research within the park, preparing scientific interpretations and explanatory panels for the geosites, andeducational and promotional activities. The Bureau has a budget to hire two specialists (geologists or relevant specialists), but at
the time of writing one post is vacant, and the Bureau is advertising to fill it.
The Academic Research Working Group supports these scholarly activities, and has 17 members drawn from the natural sciences,including the geosciences and ecology, social sciences, archaeology, and conservation. The Education Working Group is
primarily a contact body with local schools, and both shares information and holds meetings to present the results of educational
activities.

fig. 4 Organization structure

6A.4.3 Supporting Units/ Members
The Geopark receives a range of academic, research and capacity-building advice, as well as joint-research, geoguide educationand geoscience lecture support from Shizuoka University (one of the National Universities of Japan). Efforts are ongoing to
expand academic outreach and involve other universities and think-tanks.
Professor Masato Koyama of the Center for Integrated Research and Education of
Natural Hazards at Shizuoka University is the main academic advisor. Dr. Koyama
is a well-known volcanologist in Japan, and he has made extensive contributions to
the Geopark in the form of lectures, advisory support and publications on the
Geopark from before the establishment of the Promotion Council, and continuing
today. In addition, the Center for Integrated Research and Education of Natural
Hazards supports joint research with the Geopark.
Further, the Council has a system of support for research, with the goal of building
up scientific knowledge of the area, and it is building contacts with and supporting
researchers in a variety of fields.

Poster presentation of the research thatwas supported by the councill

A.4.4 Finances
The Promotion Council has independent funding exclusively for Geopark promotion and management. The main income
sources are financial commitments from each of the 15 administrative units, the special tourism promotion body for the Izu
peninsula, and funds allocated to the Geopark by Shizuoka Prefecture Government. The structural costs, such as visitor center
management, explanation panel construction, managing trails, parking spaces and toilet facilities, are met from the common
funds of the 15 administrative units, as subsidized by Shizuoka Prefecture. The chart below gives a summary of the available
budget.
Table 1 shows the management budget, and Table 2 the budget for hard infrastructure.
Table 1 Izu Peninsula Geopark Promotion Council maintains its own budget(Units: ¥1,000)

Council Budget

2011
33,7592012
30,0002013
38,0482014
39,4402015
45,2402016
40,240

Table 2 Expenditure on Geopark Facilities by local authorities, subsidized by Shizuoka Prefecture(Units: ¥1,000)
2011

2012

2013

2014

2015

2016

Total Expenditure

140,034

329,919

465,061

384,528

374,313486,300

Prefectural Subsidy

70,000197,700

286,900

196,400

199,300

296,700

A.5 Application contact person
Izu Peninsula Geopark Promotion Council
President: Yutaka Kikuchi
838-1 Shuzenji, Izu-shi, Shizuoka-ken, Japan. 410-2416
Tel: +81-558-72-0520
Fax: +81-558-72-1355
E-mail: info@izugeopark.org

7

Yutaka Kikuchi

Dr. Masato Koyama

President of Izu Peninsula
Geopark Promotion Councill

The main academic advisor

B. Geological Heritage
B.1 General geological description of the proposed Geopark
The Izu peninsula is located at the northern edge of the Philippine Sea plate, at the far northern end of the Izu-Bonin arc. The
Izu-Bonin arc was born where the Pacific plate, an oceanic plate, subducts under the Philippine Sea plate, another oceanic plate.
This subduction continues today, and an arc of volcanism and an archipelago of volcanic islands have been formed along with it.
The Izu peninsula and its adjacent seas form the northern extremity of this active volcanic arc (fig. 5, fig. 6).
The Philippine Sea plate, carrying the Izu-Bonin arc on its eastern edge, is moving northwest relative to the Japanesearchipelago (Honshū Arc), which straddles the boundary between the Eurasian and North American (Okhotsk) plates. In thearea of the Izu peninsula, it moves about 3cm/year relative to the North American plate. To absorb this motion, the Philippine
Sea plate is subducting beneath the Eurasian plate at the Suruga-Nankai trough and Ryūkyū trench, and beneath the North
American plate at the Sagami trough. However, the Izu-Bonin arc, an active volcanic arc with a thick, buoyant crust, cannot
easily be subducted, and is colliding with the Honshu arc. The Izu peninsula is located at the very point of collision.
Due to this tectonic pattern, the Izu peninsula is sandwiched between two plate subduction boundaries: the Suruga trough in thewest, and the Sagami trough to the east. As a result, within 20km of the east and west coasts of the peninsula there are deep seasof 1500–2500m, and plate boundary earthquakes of magnitude 8 or more arise there every 100 to 300 years. The shaking andtsunamis caused by these earthquakes have repeatedly inflicted great damage on the Izu peninsula.

North American PlateTokyo

Eurasian Plate(Okhotsk Plate)
AkaishiMountains(Amurian plate)

Nank
ai
Trou
gh

Tanzawa
Mt.Fuji Mountains

8～10cm/year
N35°

Pacific Plate
Izu-Oshima Island

Izu Peninsula

3～6cm/year

Niijima Island

Philippine Sea Plate

Miyakejima Island

N34°

Philippine Sea Plate

Geopark area (Terrestrial)
E138°

E139°

Source : ETOPO2

fig. 5 Tectonic situation of the Izu Peninsula and adjacent areas

8

N33°
E140°

On the other hand, as the ridge of the Izu-Bonin arc
extends south from the southern end of the peninsula,this area is occupied by a large area of shallow ocean,under 500m in depth, studded with many islands. Theseislands, the Izu islands, are almost all volcanic islands,
and many submarine volcanoes have also been
identified in the surrounding area. Many of theseterrestrial and submarine volcanoes are active. These
active volcanoes have erupted many times in thehistorical period, and the eruption of Izu Ōshima in1986 and of Miyakejima in 2000 led to the evacuationof the entire population of those islands.
Further, where the north and northwestern edges of thepeninsula form the collision zone with the Honshu arc,
the Ashigara, Tanzawa, Misaka, Tenshu, and Akaishi
fig. 6 Izu Peninsula at plate junction
fold mountains rise up to 1000 to 3000 m, and thecompression and uplift continue today. This area also includes the Fuji River Mouth and Kannawa-Kozu-Matsuda fault zones.
Further, continental Quaternary volcanoes such as the Fuji volcano and Hakone volcano have erupted to cover the area, andsome of them are still active. Fuji volcano had a large scale eruption in 1707, and even Hakone volcano saw a small scale
eruption in 2015.
The interior of the Izu peninsula, that is, the region within the Izu Peninsula Geopark, is mostly occupied by eroded mountains
with a height of under 1400 m, such as Amagi volcano and Daruma volcano, and there are no large rivers or plains. The only
significant river is the Kanogawa river, which flows north from the region around Amagi volcano, and the largest plain in the Izu
peninsula, the Tagata plain, is found in its downstream region. As the peaks of the Izu peninsula are surrounded by water on threesides, the moist air from the sea brings annual rainfall of as much as 4000 mm. This means that landslides and similar disasters
often occur, and the Kanogawa river and Tagata plain are both notorious for flooding. In addition, lava and mud flows from Fuji
volcano in the north, and pyroclastic and mud flows from Hakone volcano in the northeast, sometimes reach the plain.
The basement of the mountain range that makes up the
Izu Peninsula Geopark is composed of Neogene
submarine volcanic rock, and Quaternary volcanoes suchas Amagi volcano are distributed on top (Fig. 5).
However, in the last 150,000 years the Izu Tobu volcanogroup, an independent monogenetic volcano group of a
type that is rare in the Japanese archipelago, has become
active, and over 100 small volcanoes are scattered acrossthe eastern Izu peninsula and the adjoining sea bed (fig. 7).
The only currently active volcanoes in the Izu peninsula
are in this Izu Tobu volcano group. The magma reservoir
for the Izu Tobu volcano groups gives rise to earthquake
swarms from time to time, damaging the surrounding areaand leaving people unsettled. In July 1989, the firstsmall-scale eruption on the Izu peninsula or within its
surrounding waters in 2700 years occurred, on the sea bed
off the coast of Ito.

fig. 7 Distribution of terrestrial volcanoes

9The influence of the collision between the Izu-Bonin and Honshū arcs can be seen in
the crustal movements of the Izu peninsula, where the east coast is undergoing uplift
while the west coast subsides. The evidence for this can be seen in wave-eroded
platforms, and the other geomorphology of the coasts. Further, many active faults,
most prominently the Tanna fault, lie in the region, and have repeatedly given rise tomagnitude 6 to 7 earthquakes over the course of history, such as the magnitude 7.3
North Izu Earthquake in 1930, and the magnitude 6.9 Izu Peninsula Oki Earthquake in
1974. These earthquakes have done a lot of damage to the peninsula.
This completes the summary of the present geological situation of the Izu peninsula
and its surrounding region, but it is worth noting that many research findings also
directly support the assumption that the Izu peninsula was located further to the southin the past. In other words, the Izu peninsula is an allochthonous crustal block thatwas brought into collision with Honshū by the northwards movement of thePhilippine Sea plate. Strata and rocks from almost the whole of the past 20 million
years are found at the surface across the peninsula, and it is possible to follow afaithful geological record from before the collision with the Honshū arc, that is, fromwhen the peninsula was located to the south (Figs 6 & 7).
The strata and rocks found in the Izu peninsula can be broadly divided into two groups.
The lower (20 to 2 Ma) are pre-collisional submarine volcanics (Nishina group,
Yugashima group, Shirahama group), and the upper (from 2 Ma) are post-collisionalterrestrial volcanoes (the Atami group). The former are strata from the long
pre-collisional period of submarine volcanism, while the latter are strata dating fromafter collision and continental uplift. Further, at the base of the latter are syn-collisional
trough-filling sedimentary rocks, which built up in the trough that formed between theIzu peninsula and Honshū during the collision.
Most of the submarine volcanics in the lower strata are made up of volcanic rocks
from submarine eruptions and the associated secondary sediments and intrusive rocks.
These strata and rocks, which were originally on the sea bed, have been widely
exposed on the surface as a result of uplift and emergence caused by the collision.
When compared to the older Nishina and Yugashima groups (from 20 Ma to 10 Ma),the younger Shirahama group (from 10 Ma to 2 Ma) contains many shallow-water
fossils and terrigenous volcanic rocks. This shows that, over time, the island arc
developed, and shallow seas and volcanic islands appeared. Further, the low dip of thepaleomagnetic traces in these rocks and strata, along with the marine fossils, showthat the Izu region was, at the time of eruption or deposition, located at a lower
latitude than at present, in the tropical or sub-tropical zones.
Later, between 2 Ma and 1 Ma, concomitant with the collision with Honshū and uplift,
sea floor sediments disappear from the strata, and by around 1 Ma the whole of theIzu peninsula became terrestrial. The strait between Izu and Honshū, joining the
Suruga and Sagami troughs, disappeared due to sedimentation and uplift, and by
about 600,000 years ago, the present form of the peninsula was established.

fig. 8 Geological history of Izu
Peninsula since 20 million years ago

10Volcanic eruptions continued across almost the whole of the peninsula after it became a landmass, and by about 200,000 BP thelarge scale terrestrial volcanoes such as Amagi volcano had formed, and the mountainous scenery that we see in the peninsula
today had taken shape. From about 150,000 years ago, the independent monogenetic volcanoes of the Izu Tobu volcano group
have erupted until the present.

fig. 9 Simplified geological map and structure of Izu Peninsula

11

fig. 10 Geological map of the Izu Peninsula Geopark12

B.2 Listing and description of geological sites within the proposed GeoparkID

Si te N a me
1 Momozawagawa River
2 Surugadaira
3 Southern foot of Ashitakayama Volcano
4 Nagakubo
5 Southwest foot of Hakone Volcano
6 Ayutsubo Falls
7 Mishima
8 Kubo waterspring
9 Kiyozumi Green Area, Maruike Pond

10 Gekko Astronomical Observatory
11 Tashiro Basin
12 Jikkokutoge Pass
13 Izusan
14 Kakitagawa River
15 Tanna Basin
16 Atami
17 Mt. Kanukiyama
18 Senbonhama, Ushibuseyama
19 Ohira
20 Kashiya
21 Mt.Kurotake
22 Ikenoyamatoge Pass
23 Cape Uomizaki
24 South Nirayama Pass
25 Izunagaoka
26 Sizuura, Uchiura
27 Osezaki
28 Ita29 Nishiura
30 Ukihashi
31 Ajiro
32 Hatsushima Island
33 Mt. Joyama, Mt. Katsuragiyama
34 Takatsukayama Volcano, Sukumoyama Volcano
35 Usami, Oishigasawa
36 Heda37 Sanagiyama, Kinkanzan
38 Darumayama Volcano
39 Shuzenji Spa
40 Ohito, Shuzenji
41 Shimoshiraiwa, Kadono
42 Hinata
43 Kitaomi
44 Yokoyama, Umegi
45 Hiekawa, Kashiwatoge Pass
46 Ito Spa
47 Teishi Sea-Knoll
48 Okuno, Kadono
49 Joboshi
50 Cape Shiofukizaki, Kawana
51 Komuroyama Volcano
52 Lake Ippekiko, Umenokidaira Volcano
53 Funayama
54 Odoi
55 Funabara
56 Kawagodaira Volcano
57 Kokushigoe Pass
58 Maruno Highland
59 Omuroyama Volcano
60 Futo Coast, North Jogasaki Coast
61 South Jogasaki Coast
62 Ioyama Volcano, Akakubo Volcano
63 Ike64 Toi Gold Mine
65 Seigoshi Mine
66 Mochikoshi mine
67 Yugashima
68 Togasayama Volcano
69 Yahazuyama Volcano
70 Koshimoda
71 Ugusu mine
72 Nishina Pass, Nekkodake Volcano
73 Hachikuboyama Volcano
74 Namesawa
75 Cape Koganezaki
76 Ojiro, Miyagahara
77 Amagitoge Pass
78 Source of Shiratagawa river
79 Shiranutanoike Pond
80 Dogashima, Nishina Port
81 Nishinagawa River, Hozoin Temple
82 Numanokawa River
83 Kawazu Seven Falls
84 Mt. Kannonyama
85 Okusagano
86 Sekiguchi, Kawakubogawa River
87 Atagawa, Hokkawa
88 Hosono Plateau
89 Ikeshiro, Chokuroyama Volcano
90 Hachinoyama Volcano
91 Nashimoto, Yugano
92 Oike, Koike
93 Inatori
94 Hachigakubo, Ogawasawa
95 Mine, Sawada
96 Kadono
97 Matsuzaki, Sakurada
98 Iwachi, Ishibu, Kumomi
99 Cape Hagachizaki
100 Tenjinbara, Jaishi
101 Nawaji
102 Rendaiji
103 Shirahama Coast
104 Mera, Koura
105 Shimoda Port
106 Shimogamo Spa
107 Kisami, Toji
108 Yumigahama Beach
109 Suzaki
110 Cape Tsumekizaki
111 Okuiro Coast112 Irozaki Fault
113 Irozaki, Ikenohara
114 Karuizawa

D es cri pti on

V a l ue

Lava flows from Ashitaka volcano and its structure, Beech forest
The Graded Slopes at the Foot of Ashitaka Volcano
The Graded Slopes at the Foot of Ashitaka Volcano and land use
The Graded Slopes at the Foot of Ashitaka Volcano, Historic battlefield
The Graded Slopes at the Foot of Ashitaka Volcano and land use
Lava flows from Fuji volcano, Lava tree molds, Local folklore
Top section of Mishima lava and springwater, Gotenba mudflow
Spring water from the lavas by Fuji volcano, Lahar deposit, Ecosystem
Spring water from the lavas and its use
Astronomical observatory
1930 Kitaizu earthquake fault slip, Tashiro basin landscapeViewing spot ; Tanna fault, Tanna and Tashiro basin, Fuji volcano, Amagi volcano
Source of hot spring
Spring water from the lavas by Fuji volcano, Ecosystem, Environmental reconstruction
Lateral slip during 1939 Kitaizu earthquake, underground preservation of fault structure, Tanna fault model
Landscape of hot spring town
Volcanic necks, Viewing spot of large terrain
Submarine lava dome at seaside cliff, tsunami related local belief at Oasa shrine
Lock gate against Kanogawa river flood
Pyroclastic deposit of Hakone volcano and tunnnel tombs
Viewing spot ; Tanna fault, Tanna and Tashiro basin
Fault valley landscape
Early phase submarine volcanic deposits from Taga volcano
Cross section of Taga volcano(Strato volcano)
Submarine volcanic deposits, Kitaema tunnnek tombs, Kanogawa drainage canal and repository
Submarine volcanic necks and other deoisits, Outlet of Kanogawa drainage canal
Osezaki volcano lavas and vent, Sand spit and freshwater lans, Juniper forest
Ita volcano lavas, Sand spit and Myojin pond, Sungo ancient tombs
Submarine volcano deposit, Kanogawa drainage canalFault valley landscape
Volcanic ejecta of Taga volcano
Terraced terrain and uplift
Volcanic neck, Tuff stone quarry ruin
Scoria cone and maar of Izu Tobu Volcano GroupLava flow from Usami volcano, Stone quarry ruin
Good harbor formed from sand spit, Deep-sea organisms, Tsunami related forest
Landscape of large terrestrial volcanoes
Landscape associated with the collision between Izu and Honshu
Submarine volcano deposit and Hot spa
Gold mine ruin, Kanogawa river and life of local resident
Calcareous sandstone cliff, Lepidocyclina fossil
Outcrop of Turbidite
Usami volcano lava flow landscape and its land use
Sandstone/mudstone and gravel from the last sea od Izu block
Lava dome, Obsidian that was used in ancient times
Townscape of historical hot spa, Disaster(Tsunami) remains
Latest eruption of Izu Tobu Volcano Group, Volcano disaster
Lava from Kadono and Omuroyama volcanoes, Dam and society, surrounding landscape
Tuff Ring of Izu Tobu Volcano Group
Surf benches and wave-cut notches resulting from coseismic uplift
Scoria cone of Izu Tobu Volcano Group
Maar of Izu Tobu Volcano Group, Vegetation of wetlands
Cross section of Darumayama volcano(Strato volcano)
Cross section of Darumayama volcano(Strato volcano), Terraced rice fields
Lava flows of Izu Tobu Volcano Group and land use
Pumice lava layer and pyroclastic flow, Spring water from lava, Japanese horseradish field
Maar of Izu Tobu Volcano Group and its land use
Scoria cone of Izu Tobu Volcano Group and lava flow landscapeLargest scoria cone of Izu Tobu Volcano Group, Ecosystem maintained by mountain firing
Lavas flowing into the sea and related ecosystem
Lavas flowing into the sea and related ecosystem
Scoria cone of Izu Tobu Volcano Group
Damming of the river by the lava from Omuroyama volcano, Rice paddy fields created by the land reclamation
Gold mine ruinGold mine ruinGold mine ruin
Submarine volcano deposits, Gold mine ruin, related Novels
Scoria cone of Izu Tobu Volcano GroupLava dome of Izu Tobu Volcano GroupLava flows og Tanaba volcano ,Shrine associated with the tsunami
Silica mine ruinLandscape Of Nekko volcano, land use
Scoria cone and lava flow of Izu Tobu Volcano Group, Waterfalls, land use, related novels
Lava flow of Izu Tobu Volcano Group, related novels
Hydrothermal alteration
Dammed lake formes by landslide
Landscape of large terrestrial volcano, fault lake and its ecosystem,
Sulfur mine ruin
Freshwater pond formed by land slide, ecosystem around the pond
World-famous reserch field of submarine volcanoes
Oldest strata in Izu Penunsula, Pillow lavas
Lava flows of Izu Tobu Volcano GroupLava flows and waterfalls of Izu Tobu Volcano Group, Columnar joint, Colony of fern
Submarine volcano deposits and Stone Buddha made by tuff stone
Lava flows of Izu Tobu Volcano Group and its structure
Scoria cone of Izu Tobu Volcano Group
Cross section of stratovolcano, Hot spring, Geothermal utilization
Southeastern slope of Amagi volcano and surrounding panorama, Wetlands formed by lahar and its ecosystem
Landscape of Chokuro volcano, mine ruin
Scoria cone of Izu Tobu Volcano Group, Scoria deposit
Lepidocyclina fossil
Maar of Izu Tobu Volcano Group, Scoria deposit
Scoria cone of Izu Tobu Volcano Group and its cross section, Hot spring
Scoria cone of Izu Tobu Volcano Group, Folktales related to landslide disasters
Fountain of hot spring
Fossils in submarine volcano deposits
Cross section of submarine volcanoes
Volcanic neck, Tuff stone quarry ruin, faith associated with volcano eruption
Hydrothermal alteration
Landscape of Jaishi volcano
Gold mine ruinGold mine ruin, Townscape of hot spa
Calcareous sandstone include fossil, faith associated with volcano eruption
Magmatic dike, Folklore associated with the dike
Volcanic necks, Tsunami
Hot spring, Geothermal utilization, Stone quarry ruin
Sea cave and sand bank, Uplifted fossils
Cross section of Submarine volcanoes, Sand spit, Tsunami disaster prevention facility
Submarine volnoca deposits, Subaqueous debris flow deposit, Ritual ruins
Columnar joints of intrusive bodies, hydrothermal alteration
Large outcrop of submarine volcano
Active fault and 1974 Izu hanto oki earthquake
Outcrop of submarine and terrestrial volcano, Active fault
Fault valley and stream capture landscape13

National

National
International

International

International

International

National

National

National

International
National
National

National

National

International
International
National

International

International

International
National
Internationalg eol og i ca l

cul tura lbi ol og i ca ldi s a s ter

TannaBasin

Darumayama
volcanoShimoshiraiwa
KadonoOmuroyama
volcanoNishinagawa river
HozoinDogashima
Nishina port

KawazuSeven Falls

KisamiToji
Okuiro coast
Irozaki
Ikenohara

fig. 11 Distribution of the sites of Izu Peninsula Geopark(The numbers in this map corresponds to the ID of the previous page.)14

This section describes geosites that allow the characteristic and varied geological history of the Izu peninsula, as described in
section B.1, to be clearly grasped. Here and in section B.3 we will describe ten geosites of high value in detail, and the othergeosites are listed and briefly described in the appendix.

Site 1: Darumayama volcano - Southern Volcanic Islands in Collision with Honshū – →(fig. 11 Site ID: 37)
The ideal place to experience the collision of the Izu-Bonin and
Honshū arcs is in the north of the Izu peninsula.
This location is on the ridge of the Daruma volcano, at anelevation of 630m. The ridge was formed during the terrestrial
volcanism that followed the collision, and looks down on
Suruga bay, with Fuji volcano and Hakone volcano beyond.
Izu Peninsula
Further in the distance, one can see the fold mountain ranges
created by the collision: the Tanzawa mountains. The strata androcks making up the Tanzawa mountains are also part of the
Izu-Bonin arc, which collided with and were absorbed by
3D topographic map of northern Izu Peninsula andHonshū before the collision of the Izu peninsula.
Izu-Honshu collision zone
The Suruga trough, which forms the current plate boundary
between Honshū and the Izu peninsula, is found on the bed of Suruga bay. This plate boundary runs east to connect to the
Sagami trough, passing under Fuji volcano and Hakone volcano e and the Tanzawa mountains.

Panoramic view of the Izu-Honshu collision zone from Darumayama

Site 2: Shimoshiraiwa, Kadono - Southern Volcanic Islands in Collision with Honshū - →(fig. 11 Site ID: 41)
A strata of calcareous sandstone bearing an unusual number of fossils is
sandwiched between the turbidite strata of the Yugashima group, laid downby the submarine volcanoes of the central Miocene period.
In the Shimoshiraiwa region of Izu City, many marine fossils from thesouthern seas of 11 Ma, such as foraminifera, coral, sea urchin spines, andshell fragments, have been found in the calcareous sandstone that dips
towards the east at an angle of 30º to 40º. These fossils include large,
tropical to sub-tropical foraminifera such as Lepidocyclina and Miogypsina.
At this period, the warm period had finished in the rest of Japan, which was
Fossil-bearing calcareous sandstone at
influenced by cold currents, and so the occurrence of these fossils in the Izu
Shimoshiraiwa, Izu City
peninsula alone is evidence showing that, at that time, the peninsula was
located far to the south of the rest of Japan. Further, the paleomagnetism of
the calcareous sandstone shows a low dip, meaning that this region used to
be at a low latitude (20º to 30º north).
The large foraminifera fossils at this location are a Prefectural Natural
Monument. They can be seen with the naked eye, making this an importantgeosite for understanding the geohistory and plate movements of the Izu
peninsula.
Fossils from the calcareous sandstone at
Shimoshiraiwa, Izu City

15

Site 3: Nishinagawa River, Hozoin - Oldest Strata of the Izu Peninsula - →(fig. 11 Site ID: 81)
The basin of the Nishina river, which flows through western Izu, is the site of
the oldest strata in Izu, the pillow lavas of the Nishina group, and thus vital toan understanding of the roots of the peninsula.
The pillow lavas exposed at this location are water-modified grey-green
phenocryst-free basalt, in tubular forms of 30 to 80 cm in diameter. There aremany almond-shaped inclusions of minerals such as chlorite, packed with air
bubbles, within the basalt, and the stone has been used to line baths and washbasins in hot spring resorts due to this distinctive pattern. In addition, a double
dike can be seen passing through the pillow lavas at this point. This strata has
been dated to the early Miocene on the basis of calcareous nanofossils found in
Pillow lava at Ishiki, Nishi-Izu Town
the fine-grained tuff in the same area.
Site 4: Dogashima, Nishina Port – Submarine volcanoes- →(fig. 11 Site ID: 80)
The Shirahama group (late Miocene to Pliocene), which overlies thevolcanic bomb
Yugashima group, was built up by submarine eruptions in the shallow seasaround the volcanic island arc, and is made distinctive by various rockformations derived from this origin.
In the area around Dogashima in NishiIzu Town, submarine volcaniclastic
flows, pumice and volcanic ash that fell and built up on top of them, andwater-fractured lava that flowed along the seabed are widely distributed, andcontinuously exposed along the coast. Further, through studies of fossils, thedates of eruptions and order of layers, and the deposition environment, have
Photp4-1 : Submarine volcaniclastic flow
been constrained. As a result, a great deal of research has been carried out
underlies the cross-laminated tuff at
Dogashima
here into submarine volcanoes.
Along the southern Dogashima coast, submarine volcaniclastic flows andpumice and ash strata covering them can be observed. From thermal history
measurements on gravel incorporated in the volcaniclastic flows, it isestimated that they were embedded at a temperature of 450 to 500 ºC. The
upper levels of the volcaniclastic flow gradually transition to thoroughly
cross-bedded tuff while retaining their dominant trough shape, indicating that
this was part of the same activity. Further, these strata contain volcanic bombs
Photp4-2 : Sea cave with a beautiful skylightwith a history of sudden cooling.
at Dogashima
These favorable conditions for research contributed to the construction ofearly theories of explosive sea-floor eruptions (see, for example, Cashman and Fiske 1991).
Sea erosion has created caves in the cliffs of exposed volcanic material, and it is possible to enter the caves in boats and enjoy
the numinous atmosphere created by the “skylights” in the cave.
Fuji volcano
Photp4-2
Photp4-1

Nishina Port
Western coast of Izu peninsula and location of Dogashima, Nishi-Izu Town

16

Site 5: Okuiro Coast – Submarine volcanoes→(fig. 11 Site ID: 111)
There are many intrusive bodies in the Shirahama group. Somelarger intrusive bodies have been exposed by erosion, and rise up
here and there across the peninsula as volcanic necks. Smaller ones
decorate cliffs as dikes and sills with columnar joints. Together, theycreate a distinctive landscape.
The Southwestern Izu Coast, a National Site of Scenic Beauty, is animpressive coastline where many eroded intrusive masses take onremarkable shapes. Large numbers of intrusive bodies are exposed atCape Mitsuishi, a part of this coast. Submarine volcano deposits arecross-cut by many andesitic intrusive bodies which range in size
from less than a meter to several hundred meters at this cape.
Relationships between the beds and the intrusive bodies are assumed
to have originated mostly by interaction between hot magma andpoorly consolidated wet sediments at a shallow depth beneath the sea
floor.
These are a good example for understanding the realities ofsubmarine volcanic activity in the back-arc and shallow waters of therift zone of volcanic island arc.

Photp5-1

Photp5-2

The intrusive bodies which appeared on cross sectionin the submarine volcano

Cape Mitsuishi Photp5-1
Photp5-2

Iruma Port

Okuiro coast of Izu peninsula, Minami-Izu Town

17

Site 6: Irozaki, Ikenohara – The uplift of the whole Izu peninsula and subsequent terrestrial volcanism –→(fig. 11 Site ID: 113)
When, one million years ago, the Izu peninsula became a continental land mass due to the collision between the Izu-Bonin and
Honshū arcs, the volcanoes continued to erupt despite changing from submarine to terrestrial. In other words, the end of thelong period of submarine volcanism was the beginning of the period of terrestrial volcanism. The evidence of this can be seenaround Irozaki, at the southern tip of the Izu peninsula.
At this point, lava and scoria from the Nanzaki volcano (K-Ar date of 430,000 BP), in the Atami group, directly overlie thewhite submarine tuff of the Shirahama group. A brown weathered layer has formed on the upper surface of the Shirahama
group.
Visitor center
Yusuge park

Terrestrial lava and scoria of Nanzaki Volcano
overlie submarine tuff of the Shirahama GroupSouthern coast of Izu peninsula and location of
Yusuge park, Minami-Izu Town

Site 7: Omuroyama Volcano – The Active Monogenetic Volcano Group - →(fig. 11 Site ID: 59)
After the collision with the Honshū arc, eruptions of large-scale
Omuroyama Scoria Coneterrestrial volcanoes continued, but about 150,000 BP a groupof independent monogenetic volcanoes (Izu Tobu volcanogroup), which are unusual in the Japanese archipelago, became
Lava field from Omuroyama
active. The activity continues today.
(Izu plateau)
Omuroyama volcano is the largest scoria cone in the Izu Tobu
volcano group, and was formed in an eruption about 4000
Ippekiko Maar
years ago. From the peak, one can see the many volcanoes
scattered throughout Ito City, and landscape produced by theireruptions. The spread of the volcano group is visible.
The eruption of Omuroyama produced a great amount of lava,
Aeral view of a part of the Izu Tobu Volcano Group andwhich filled in the uneven topography that existed before thelocation of Omuroyama, Ito CIty
eruption, creating the gentle Izu plateau. Further, the lava thatreached Sagami bay created the scenic Jogasaki coast. The lava flows from the scoria cone arose from the base of the mountain.
In the final stages of the eruption the viscosity of the lava rose, creating a plug dome (Iwamuroyama) over the lava mouth.
Thanks to the annual burning of the mountain, the beautiful shape of Omuroyama, like an upturned bowl, has been preserved,
and the whole mountain is a Nationally Designated Natural Monument.

Beautiful bowl-like shape of Ōmuroyama ScoriaCone, Ito City

Panoramic view from the summit of
Omuroyama, Ito City

18

Site 8: Kawazu Seven Falls – The Active Monogenetic Volcano Group - →(fig. 11 Site ID: 83)
Lava flows from the Izu Tobu volcano group have created beautiful waterfalls in many locations. The Nanadaru falls in Kawazu
Town are one example.
Around 25,000 years ago, lava from the Noboriominami volcano that appeared on the southern slope of Amagi volcano flowed
about 2 km down the valley of the Kawazu river as it filled it in. Seven waterfalls were created by the elevation changes in thelava, and these are the famous Kawazu Seven falls.
The basal rocks of the waterfalls are carved into
beautiful columnar joints formed when the lava
contracted as it cooled and hardened, and thedifferent forms of the columnar joints at eachwaterfall create a dynamic landscape.
The Kawazu Seven falls and the nearby Amagi Pass,a difficult pass linking north and south Izu, are thesetting for “The Dancing Girl of Izu”, a famousnovel by the Nobel laureate Yasunari Kawabata,
who loved Izu. The area is visited by many hikers
tracing the dancing girl’s journey.
The Kawazu Seven falls, are far from the only
waterfalls created by lava from the Izu Tobu
Lava flow with beautiful columnar joints at Kamadaru
volcano group, and others include Joren Falls andwaterfall, Kawazu Town
Namesawa Gorge. These scenic locations are often
the setting for novels or films.
Site 9: Tanna Basin – Continuing Crustal Deformation and Active Faults - →(fig. 11 Site ID: 21)
Due to the collision between the Izu-Bonin and Honshū arcs, the whole of the Izu peninsula is the site of active crustal
deformation, and is criss-crossed with active faults. Some of those have repeatedly caused magnitude 6 to 7 earthquakes in thehistorical period.
In the early hours of November 26th 1930, a strong (magnitude 7.3)
earthquake struck northern Izu. During this North Izu Earthquake, the Tanna
fault and its southwest extension, and further the Himenoyu Fault on its
southeastern side, slipped by up to 2 metres. The horizontal slip preserved in
Tanna Fault Park is a Nationally Designated Natural Monument.
The past slippage on the Tanna fault adds up to over 1 km horizontally andabout 100 m vertically. The investigations of the topography generated by thisleft-slip fault were globally pioneering, making it a world-famous site.
he slippage generated by the North Izu Earthquake directly struck the
Geomorphology of Tanna fault, Kannami
construction site of the Tanna Tunnel, being dug beneath the Tanna Basin at
Town
that time. Due to the construction of this tunnel, the Tanna region, which had
been a prosperous wasabi farming area thanks to its many springs, saw thosesprings dry up. With the help of the Railways Ministry of the time, it changed
to a dairy farming region.

Historical left-lateral displacement along the
Tanna fault, preserved at the Tanna faultpark, Kannami Town

19

Site 10: Kisami, Toji – Continuing Crustal Deformation and Active Faults –→(fig. 11 Site ID: 107)
The collision has made the whole Izu peninsula a site of active crustal
deformation. In particular, over the last few hundred thousand years, the easternside of the peninsula has been uplifted, while the western side has subsided.
Due to this, marine terraces, wave-cut platforms, and wave-cut notches arefound mainly on the east coast.
In particular, such marine terraces and wave-cut platforms extend over several
levels in the Shimoda region. There are many examples of sea caves in the
wave-cut terraces, and layers of uplifted fossils are often preserved on thesurfaces of the caves. Detailed investigation of these fossils has shown that thearea has been uplifted several times, including three in the last few thousand
years.
There are large sea caves with beautiful skylights, such as Ryugukutsu, which,
together with the nearby Sand Ski Run, has become a popular geospot. Rocks
deposited by the tsunami caused by the 1854 Ansei Earthquake have been foundon the adjacent coast.

Layers of uplifted fossils in sea cave,
Shimoda city

Skylight of an uplifted sea cave
“Ryūgūkutsu”, Shimoda City

B.3 Details on the interest of these sites in terms of their international, national, regional or local value
As explained in section B.1, the distinctive features of the Izu Peninsula Geopark arise from the northward motion of submarine
volcanoes on the Philippine Sea plate, their collision with Honshū, and the associated diverse volcanism and crustal
deformation. The Izu peninsula is globally unique as the site of a collision between two active volcanic arcs. In addition to thegeological heritage of this distinctive origin, the natural landscape, ecosystems, and culture arising from it are “Gifts ofVolcanoes from the South”. This section will discuss the importance of the geological heritage under three headings, linked to
the 10 important geosites introduced in section B.2.

1. A Unique Point on Earth — The Meeting of Two Active Volcanic Arcs (Section B.2 Sites 1 & 2)
The Izu peninsula is the location where two active volcanic arcs, the Izu-Bonin arc and the Honshū arc, meet (fig. 12). Let us
consider whether there are any other such places. Active volcanic arcs arise in subduction zones where plate subduction has
continued for some time, and the tip
Active volcanoes
Collisional zoneof the subducted slab has reached abetween Izu-Bonin
depth of around 100 km. As the
Izu Peninsula
arc and Japan arc
collision of two active volcanic arcs
must indicate that two subduction
Eurasian Platezones meet, let us first look for suchplaces. The only three candidates are
the region around the Izu peninsula,
Pacific
around Halmahera, and in the area
Platearound the Solomon Islands.
However, if we look carefully at theother two candidates, we see that as
one of the two subduction zones has
no clear volcanic chain, two active
Philippine Sea Plate
volcanic arcs do not meet there (fig.
13). In other words, the area aroundthe Izu peninsula is the only place in
fig. 12 Pseudo-3D topographic map around the Izu Peninsula (base map is by JCG)
the world where two active volcanicarcs meet clearly, and both the20

collision and the various phenomena that arise from it are in progress even now. No other Geoparks comprise a place with thissort of unique geoscientific theme.
Volcanic centers active
within the last one
million years

Izu Peninsula

Halmahera
Solomonfig. 13 Distribution of active volcanoes and Plate boundary (after NASA, 2002)
The collision of the two active volcanic arcs is reflected in the topography, geological structure, and development history of theIzu peninsula and surrounding region, and a great deal of research has been carried out there. The theory that the Izu peninsula,unlike the rest of Japan, is on the Philippine Sea plate (Sugimura, 1972), and that it is colliding with Honshu (Matsuda, 1978)
was proposed soon after the establishment of the theory of plate tectonics in the late 1960s, and in that sense we can say that
this region was identified as a collision between island chains very early, and the site of pioneering research.
After that, it was determined that, before the beginning of the collision with the Izu crustal block about 1 Ma, the Tanzawa
crustal block had collided with
Honshu, about 5 to 6 Ma. It is also
thought that another crustal block(the Misaka-Kushigatayama block)
had collided even earlier (Amanoet al., 2007). The collisions
between island arcs in this area arethus associated with discontinuousand multiple collisions, and theresulting subterranean structure has
been carefully investigated (Araiand Iwasaki, 2014). It is thoughtthat the bending, rotation, anduplift of the geological band
structure that gives central Honshu
its distinctive features has had amajor influence on geologicalstructure and topography (Tamura
fig. 14 Geotectonic structure of central Japan (left), collision of island arcs (right)（after Amano et al., 2007）
et al., 2010, Site 1,fig. 14, fig. 15).

21

NNW

SSE

Izu Peninsula

Izu PeninsulaAA’

fig. 15 Tanzawa–Izu collision zone cross-section (Tamura et al., 2010)
Further, the region around Izu, as the site of multiple collisions between island arcs, has not just been valuable for research onplate movement and collisions, but has also given rise to the working hypothesis that continental crust itself arises from thedevelopment of island arcs and their mutual collisions. A great deal of work to substantiate this hypothesis is in progress(Tatsumi and Stern, 2006; Tatsumi et al., 2008; Tamura et al. 2010).
The southern origin and northward movement of the Izu crustal block are mainly confirmed by two types of evidence:
paleomagnetism and paleontology (Geosite 2). Paleomagnetic data has been obtained from several locations on the Philippine
Sea plate (Koyama et al., 1992; Yamazaki et al., 2010,fig. 16), and using these data and geological data as constraints, thehistory of the structural development of the Philippine Sea Plate has been reconstructed (Wu et al., 2016, fig. 17). It has become
clear that the Izu crustal block rotated clockwise in the course of its northward motion

fig. 16 Northward drift of Izu Peninsula and Philippine Sea Platerevealed by paleomagnetic measurements (Koyama et al., 1992)22

fig. 17 Tectonic Evolution of the Philippine Sea Plate (Wu et al., 2016)23

The paleontological data is primarily based on Lepidocyclina foraminifera. These species flourished throughout the tropical andsubtropical regions of the world from the Eocene to Miocene (Matsumaru, 1971,fig. 18).

fig. 18 Geological distribution of larger
foraminifera Lepidocyclina and its family (Eocene
to Miocene) (Matsumaru, 1971)
Lepidocyclina Spp. were found in various areas of Honshū from the early to mid Miocene, but for some reason fossils from thelate Miocene and early Pleistocene are found only in the Izu peninsula (Ikebe 1972, fig. 19, left). This puzzling spatio-temporal
distribution is explained by the fact that in the late Miocene and early Pleistocene, when the various regions of Honshū werealready under the influence of cold currents, the Izu crustal block alone was still located further south, where Lepidocyclina
continued to flourish under the influence of warm currents (Tsuchi, 1984, fig. 19 right)

fig. 19 Distribution of larger foraminifera Lepidocyclina/Miogypsina modified from Ikebe (1972)24

2. The Varied History of the Land of Volcanoes (Section B.2, Sites 3 to 6)
In the last section we covered the dynamic origin and history of the Philippine Sea plate and the Izu-Bonin arc, but for almostthat whole period it seems that the Izu crustal block was at the edge of the Philippine Sea plate, where there was continuous
volcanic activity due to the subduction of the Pacific plate. As strata and rocks recording the last 20 million years of this history
are exposed at the surface of the Izu peninsula, a great deal of research has already been carried out. Further, recent deep ocean
drilling expeditions, such as ODP Leg 126 and IODP Expedition 350, have recovered cores from the seas around the Izu
peninsula, giving the geological and volcanological research on the Izu peninsula additional importance as a source ofcomparative data.
As already explained in section B.1, the history of volcanic activity in the Izu peninsula can be split into three periods: Neogene
submarine volcanism; Quaternary terrestrial volcanism on a large scale, after the collision with the Honshū and conversion toland mass; and the scattered activity of the independent monogenetic volcanic group, continuing from 150,000 years ago until
the present day. This volcanic activity, occurring at different times and in different environments, has left visible many different
aspects of volcanoes. These range from the subterranean structure of old submarine volcanoes, exposed as volcanic necks androck structures (Sites 3 to 5), to the newly-minted volcanic forms and eruption products of the active Izu Tobu volcano group.
At some locations, you can even see the transition from submarine to terrestrial layers of volcanic ejecta (Site 6).
In the Izu Peninsula Geopark, you can enjoy these volcanoes and the landforms and rocks they have produced as an organic
whole (Koyama 2009, 2010, 2012, 2013, 2014, 2015a, 2015b). There are already a significant number of Geoparks, both inJapan and in the rest of the world*, that take volcanoes as their theme, but the Izu peninsula stands out. Nowhere else is it
possible to trace the multifarious and dramatic changes of volcanism over such a long period of time, as the environmentchanges from deep sea, to shallow sea, to terrestrial, and as the change in stress field caused by a collision transforms thevolcanism from large scale to monogenetic.
In particular, it should be noted that the collision between the Izu peninsula and the Honshū arc, resulting in rapid conversion tocontinental crust followed by erosion, means that submarine volcanoes, which cannot normally be viewed, are exposed allalong the coast, creating an ideal research environment. As result, a great deal of work has been carried out, particularly on thewest and south coasts (Ito et al., 1984, Matsumoto et al., 1985, Kano, 1989, Tamura et al., 1991, Cashman and Fiske, 1991,
Jutzeler et al., 2014, 2015, 2016), and the Izu penisula can be described as a driving force behind global research on submarine
volcanoes.
*The following Geoparks take active volcanoes as their theme. Global: Katla, Reykjanes (Iceland); Jeju Island (South Korea); Toya Caldera and Usu
Volcano, Unzen Volcanic, Aso (Japan). Japanese: Mt Bandai, North Slopes of Mt Asama, Hakone, Izu Ōshima, Kirishima, Sakurajima/Kinkowan.

fig. 20 Mode of emplacement of intrusive bodies in the southern coast of Izu Peninsula, estimated by method of
structural geology (Kano, 1989)
For example, Kano (1989) used principles of structural geology to explain the complex intrusive bodies found across south andwest Izu (Site 5) in terms of the penetration of magma into unhardened sediment. Tamura et al. (1991) showed that submarine25

volcaniclastic sediments (Site 4) were the product of gravitational flow concomitant on an eruption, by using magnetic
petrology to investigate the thermal history of included gravel, and showing that its fixing temperature was 450 to 500 ºC.
Cashman and Fiske (1991) carried out detailed analysis of the terminal velocity of pumice and volcanic rock particles in thesame sediments, and by comparison with particle size showed that they had fallen underwater. These results are internationally
important and pioneering in the fields of intrusion, eruption, and deposition by submarine volcanoes.
At the Izu Geopark, materials are made available explaining the varieties of submarine volcanic ejecta and what to look for on
the ground by summarizing this research in an easily-understood way (Koyama 2012, fig. 21). The research on the monogenetic
volcanoes also deserves special mention, but as it concerns active volcanoes it will be covered in the next section.

Guide to submarine volcanic products (Koyama, 2012)

Mode of emplacement of volcaniclastic flows at
Dogashima, estimated from thermo-petromagnetic
analysis (after Tamura et al., 1991)

fig. 21 The material to explain an earth science phenomenon

3. Dynamic Scenery Born of Ongoing Collision and Volcanism (Section B.2 Sites 7 to 10)
The biggest difference between the Izu peninsula and other Geoparks is that the collision between two active volcanic arcs andthe accompanying changes are still ongoing. As a result, the Izu peninsula is undergoing continuing crustal deformation andmany faults are active even now. Further, the Izu peninsula is sandwiched between two plate subduction boundaries, in the
Suruga-Nankai trough to the west and the Sagami trough to the east. The Suruga-Nankai trough generates plate boundary
earthquakes every 100 to 200 years on average, while the Sagami trough does so every 250 years or so.
The active terrestrial faults generate plate interior earthquakes in themagnitude 6 to 7 range every few hundred to few thousand years,
while the adjoining seabed generates plate boundary earthquakes ofaround magnitude 8. The peninsula has been repeatedly assaulted bythese tremors and, in the latter case, tsunamis. There are relatively
recent examples of earthquakes that caused significant damage to thepeninsula: for plate interior earthquakes, the magnitude 7.3 Tannaearthquake in 1930, and the 1974 Izu Peninsula Oki earthquake, andfor plate boundary earthquakes, the magnitude 8.4 Ansei earthquakeof 1854 and the magnitude 7.9 Great Kanto Earthquake of 1923
(Usami et al., 2013). The tsunami caused by the 1854 Ansei
earthquake struck the port of Shimoda, and its destruction of theRussian battleship Diana, anchored in Shimoda bay while
fig. 22 Contemporary paintings recorded the tsunami
negotiations to open Japan took place, is well known (fig. 22).
caused by the 1854 Ansei Earthquake26

On the other hand, as the Izu peninsula is directly above the active volcanic arc generated by the subduction of the Pacific plate,
it is densely populated with Quaternary volcanoes, including active volcanoes. The magmatic activity of the monogenetic
volcano group found in the peninsula and adjoining seas, the Izu Tobu group, continues sporadically. In July 1989 there was asmall seafloor eruption about 3 km offshore of the town of Ito in northeastern Izu, and although it was the first in about 2700
years, it scared the local residents (Koyama 2015).
In addition, the continuing collision and uplift have given the Izu peninsula a rugged topography, which leads to high rainfall.
That, in turn, means that landslides, floods, and similar disasters are historically common, including those caused by the
Kanogawa typhoon of September 1958 (MLITT Numazukawa Roads Office).
As we can see, the Izu peninsula has been assaulted by the forces of nature over both geological and historical time, but if wetake the long view these same phenomena are also responsible for creating the dynamic and beautiful scenery of the peninsula.
The active monogenetic volcanoes of the Izu Tobu volcano group have, over the geologically extremely short period of 150,000
years, created a veritable outdoor museum of volcanoes: a landscape studded with over a hundred scoria cones, tuff rings, maars,
and lava domes, and overlaid with the lava, pyroclastic flows, and ejecta from those volcanoes’ eruptions (Koyama, 2010,2015a, 2015b). Furthermore, these beautiful volcanoes and ejecta landforms have suffered almost no erosion, and are all but
perfectly preserved (Sites 7 and 8).
Beyond that, by carefully analysing the order of deposition of the ejecta from these volcanoes and their periods, changes in thelocation and type of eruption, the existence of simultaneously erupting fissures, and the relationship with the crustal stress field
have all been determined (Hayakawa and Koyama 1992, Koyama et al., 1995, Koyama 2015, Koyama and Suzuki 2016, fig.
23). This knowledge is used together with geophysical monitoring data in the construction of hazard maps and eruption
scenarios, and is being used in the prediction of eruptions in the Izu Tobu Volcano group and in disaster mitigation strategies(Shizuoka Prefecture, 2011; Japanese Meteorological Agency 2011,fig. 24, fig. 25). Monogenetic volcano groups for which theeruption history is known in such detail and used in eruption scenarios and disaster mitigation plans, are very few*.

fig. 23 Time and spacevariation of eruptive site,mass and rock type of eachmonogenetic volcano of
Izu Tobu Volcano Group(Koyama, 2015)

fig. 24 Hazard map of Izu Tobu Volcano Group(Shizuoka Prefecture, 2011)

fig. 25 Eruption scenario of Izu Tobu
Volcano Group (Shizuoka
Prefecture, 2011)27

* The Izu Tobu volcano group is an independent volcano group with no parent volcano, which is rare in the Japanese archipelago.
There are two UNESCO Global Geoparks including independent monogenetic volcano groups, Vulkaneifel (Germany) and
Wudalianchi (China), but in neither case is the eruption history as clear as it is for the Izu Tobu Volcano group, and there is noevidence of contemporary subterranean magma activity. As the long-term eruption frequency is low, there is no disaster mitigation
strategy in either place. In areas that are not Geoparks, the eruption history of the Aukland monogenetic volcano group (New Zealand)
is understood to some extent, and there is a disaster mitigation plan in place.

On the other hand, the collision with the Honshū arc has created many active faults and much uplifted topography in the Izu
peninsula. The most famous and notable of these faults is the Tanna fault.
The Tanna fault is running north-south in the northern part of the Izu peninsula, showing left-lateral slip. Its most recent activity
was in 1930, and caused a magnitude 7.3 earthquake. In the wake of this earthquake, topographical and geological research was
carried out, and discovered left slip of 1 km along the fault (Kuno 1936). This was the first time that slip of such distance had
been discovered. After that, detailed topodynamical research was carried out (Matsuda 1972), and from the early eighties thehistory of the fault’s activity was investigated through trenches (Tanna Fault Excavation Research Group, 1983; Earthquake
Research Institute, 1988; Kondo et al., 2003). As a result, its detailed activity history (on average, once in a thousand years) has
been determined (fig. 26). The discovery of nine slip events in a single trench was unprecedented in the early 1980s, and thisresearch demonstrated the value of this research method. In other words, we can say that, along with the discovery of thelarge-scale lateral slip in the 1930s, the research on the Tanna fault has led global research on faults, and it is raised in astandard textbook on paleoseismology (McCalpin and Nelson, 1996). Recently, it has also been discovered, based on
paleomagnetic studies, that the block defined by the Tanna fault and the fault group to its east is undergoing large-scale
structural anti-clockwise rotation (Koyama 1982, 1992, Kimura et al., 2011).

fig. 26 Trench excavation survey on Tanna Fault. Left photo shows the upper part of the fault sketch on the right(Earthquake Research Institute, 1988)
The 1 meter of lateral slip arising from the 1930 North Izu
earthquake is preserved in two locations as a nationally designated
Natural Monument. One of these locations is now a park, with afacility allowing the subterranean structure to be viewed from a
trench, and this is one of the core sites of the Geopark (Site 9).
Based on the fact that, in broad terms, marine terraces and upliftedwave-cut platforms and notches are only found on the eastern
coast, it is believed that, over the last few hundred thousand years,
crustal deformation has been proceeding with uplift in the east andsubsidence in the west. In recent years, research on the fossil upliftlayers in sea caves bored into the wave-cut platforms has advanced,
showing that there have been several episodes of uplift over the
past few thousand years, including three in the historical period.
The relationship with plate boundary and off-shore fault
earthquakes is debated, and along with the investigation of
28

fig. 27 Uplifted sea cave and fossil beds on the cave wallat Shimoda and Itotsunami deposits, the implications of this research for disastermitigation are drawing a lot of attention (Kitamura and Kobayashi
2014; Kitamura et al. 2014; Kitamura and Kawade 2015,
Kitamura et al., 2014, 2015, 2016,fig. 28).
These uplifted fossil layers are valuable sites, so they are not listed
as public sites, but rather classified as research sites and managed
appropriately to preserve them. However, a nearby large sea caveand skylight, along wth the adjacent sand deposit, are are populargeosite (Site 10).

fig. 28 Elevation and chronology of fossil beds on thewall of a sea cave at Shimoda (Kitamura et al., 2015)

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 sections B.1 and B.3, the crustal deformation arising from the collision with the Honshu arc has created a steep,
mountainous landscape in the Izu peninsula and the region to its north. As this collision zone is also sandwiched between twoplate subduction troughs, both the land and the sea have exceptionally steep and varied topography. The shallow seas and flowof the Kuroshio current along the coast of the peninsula are responsible for a rich marine environment and a warm climate.
Further, the uplifted mountains of the peninsula receive a lot of rain, which generates many springs at the boundary between thepermeable terrestrial volcanic rock and impermeable submarine volcanic rock layers.
As a result, many natural environments and ecosystems have arisen both on the Izu peninsula and in the surrounding seas. Thisrich environment, together with the geology described in section B.1, has given birth to a varied natural landscape anddistinctive local products. The local products deserving of special mention are gold deposits, silicastone deposits, various kindsof stone, hot springs, fish, tengusa seaweed, wasabi, rice, and dairy products. Local industries and society have developed on
the basis of these resources.
The steep topography of land and sea created by the crustal deformation attendant on collision meant that the peninsula was abarrier to travel between east and west Japan, but for that very reason it came to play an important role in such communication.
In particular, when sea travel was at its height, ports like Shimoda and Mera flourished. A prime example of a key transport
point on land is Nirayama, the administrative capital of the old Izu region. The number of surviving religious artifacts,
particularly Heian period (794–1192) Buddhist images, show that this region was also a spiritual center.
This geographical nexus became both a meeting point for the cultures of east and west Japan, and a strategic base for the rulersof every period. The Kamakura Bakufu (13th century), established by the Nirayama-based Minamoto and Hojo families, and
the World Heritage-listed Nirayama reverberatory furnaces built by the Nirayama magistrate Egawa Hidetatsu were born in thisenvironment.
Thanks to this situation, the products, ideas, and culture born in Izu did not remain there, but rather created a wide cultural areaand had a strong impact on the history and culture of Japan as a whole. As ancient examples, we can see the trade in obsidian
tools, and the religious rituals performed as a high political matter by the Heian court in response to volcanic eruptions in theregion. More recently, Izu’s hot springs and seafood were treated as treasures as far away as Edo, the present Tokyo. In themodern period, many literati and artists, drawn by the spectacular scenery and local products, stayed in Izu, and produced many
works of art and literature. In particular, the Nobel laureate Yasunari Kawabata’s novel The Dancing Girl of Izu has been filmed
many times, and is widely popular in Japan.
Further, as Izu has been exposed to the fury of nature throughout geological and historical time, not only are the scars of pastdisasters preserved as lessons for the future, but the avoidance and mitigation of disasters is an integral part of the traditions,wisdom, skills, religion, social structure, and culture of the region. As concrete examples, we can look to the Tsunami Stones,
Wave-Breaking Jizo images, the legend of the red cow, the Tanna Fault Park, the Kanogawa River Drainage Canal, and the29

Byūo Tsunami Gate in Numazu port.
Within the Izu Geopark, beyond the specifically geological sites, there are many places worth seeing that depend on the history,
culture, and natural scenery that are so closely tied to the geological background of the region. In this section, we provide a listin Table 2.
Table 3 Non-Geological Sites and Relationship to Geopark
Category

Site Name

Kannami Virgin Forest

Water and Forests

Natural Disasters

History

OsesakiAmagi Virgin Forest

Old Amagi Tunnel

Shimoda Port

Sacred spring, juniper, connected to tsunamis and vegetation
National park special protection area, high altitude, related to precipitation

Legend of Kobo Daishi, stories of Yoritomo and the Hojo, hot springs withliterary connections
Difficult point on the Shimoda Road, appears in novels, including The
Dancing Girl of Izu, and the famous enka song “Crossing Amagi”.
Large port city on the maritime route, Perry’s Black Ships and smuggling
incident, Ansei Earthquake and tsunami and the story of the Diana,
buildings in Izu stone and black-and-white namako walls

Obsidian

Chohachi Irie’s Kote’e arts, San’yo Tsuchiya’s San’yo Juku (School),buildings in Izu stone and namako walls
Kashiwa Pass (stone tools found across central Japan), Ikadaba (Kokaseki)Izu Stone

Nirayama Reverberatory Furnaces,
streetscapeMatsuzaki

andThis watershed protection forest has been preserved since the Edo period(1603–1868), and occupies the slopes of a Quaternary volcano. It includes
500-year-old Japanese evergreen oak.
Close to geosites such as the Tanna Basin and Jukkoku Pass, it shows thegently-sloping topography of the volcano and its characteristic vegetation.

Mishima Springs
Mt Fuji springs
Kakitagawa Springs
Mt Fuji springs
Suidoyama, Ito
Scoria cone, related to landslides
Miyagahara Deep Water
Related to landslides and landslide dams
Earthquake Slip Scars
North Izu Earthquake, Nationally Designated Natural Monument
Koshimoda Mishima Jinja Shrine reached down a slope (very unusual), tsunami legends
ShrineLegend of Nichiren’s tsunami-averting prayer, Ansei Earthquake tsunami
Senbonhama-Ushibuseyama
pool, Byūo (Large tsunami water gate)
Kanogawa River Drainage Loss of the Kanogawa River’s mouth, Kanogawa Typhoon
Canal
Collapse of Jabamiyama
Pyroclastic plateau, Divine era cypress, Kanogawa Typhoon
Collapse of Kajiyama
North Izu Earthquake
Tsunami-Stones,
Records of tsunami due to Meio, Keicho, Genroku Kanto, Ansei, andWave-Breaking Jizo images, Taisho Kanto earthquakes
tsunami flood marks
World Heritage Site. Iron-making furnaces built at the end of the Edo period
for the manufacture of large guns. Izu stone is used for part of the structure.
The bricks were made from Kawazu hot spring clay. The skills of
Nirayama
construction and mining workers from the Izu area were also put to use in
Reverberatory Furnaces
the construction and operation of the reverberatory furnaces. It is part of theSites of Japan’s Meiji Industrial Revolution: Iron and Steel, Shipbuilding
and Coal Mining World Heritage Site.
Important figures from many eras were exiled to Izu, a place far from thecapital in Kyoto. One such was Minamoto Yoritomo, the founder of the
Kamakura Bakufu. Hirugakojima, to which Yoritomo is said to have been
exiled, is now surrounded by rice fields, but the Kanogawa river used to
Izu Administrative Capitalflow through the area, before its course changed. Tours telling the story of
Yoritomo and the Hojo, and the influence of geography, are alreadyhappening.
Shuzenji

Resources

Description

Industry30

EdoCastle,Odaiba,ShimodaGold deposits
Silica stone deposits
Amagi Wasabi
Pool rice culture
Ishibu Terraced Rice Fields
Vegetables from SE slopesof Hakone
Tanna Dairy
Amagi Tengusa
Deep Sea Creatures
Fish, marine products

Tago Salted Tuna Factory

Shirahama Jinja Shrine
Mishima Taisha Shrine

Religion

Hot Springs

Naranda no Sato (Nazenji)
Hotoke no Sato Museum

Hashiriyu at IzusanMinë Geyser

Izu Modern Literature Museum(Showa Forest Hall)

Literature

Intangible
Heritage

Toi gold mine etc. Second-most productive in Japan after the Sado gold
mines
Ugusu silica stone (had the largest share of industrial glass production),
Koganezaki, Crystal ParkTop share for domestic production, relation to geological structure andwater springs
Creation of rice fields by forced drainage of lakes dammed by lava flows
Related to Jaishi volcano and springs
Related to Hakone, Yugawara, and Taga volcanoes
Related to Tanna Tunnel and North Izu Earthquake
Kanten made from Tengusa seaweed using the cool and dry climate of Mt
Amagi.
Japanese Spider Crab, related to Suruga TroughRich fish and marine products of the Kuroshio current, related totopography and marine currents
Traditional preserved food of the Tago area of Nishi-Izu City. Tagoprospered from its skipjack tuna fishery, in which high-quality fish werelanded, and used to offer salted tuna when praying for safe voyages, richcatches, and prosperous descendants. As an auspicious fish, it was alsooffered as “New Year Fish”. It is possible to visit the factory, and it isincluded in tours.
Volcano deities cult
Volcano deities cult
The Izu peninsula boasts a surprisingly high number of Buddhist images atthe level of National Treasure or Important Cultural Property. This isbelieved to be because the images were shipped from Kyoto or Nara to Izu,
which was a key point on the maritime routes. As it was a common site ofexile, the exiles could easily bring the culture of the capital with them.
The connection between people and the sea, including transport, and theflow of culture in from the outside are often raised on geotours, and as anextension of that these museums are sometimes included.
All the hot springs are gifts of the colliding volcanic arcs, but only thosewhere the source can be seen or the character of hot spring country can beseen particularly clearly are registered as geosites. Even the hot springs thatare not registered are good places to relax after a walking tour.
Many authors loved the scenery and hot springs of Izuand included them intheir works, either directly described as setting, or as metaphors for the stateof mind of characters.
Many geotours also follow in the footsteps of authors and trace the courseof their works, and visit literary monuments and places associated with theauthors.

Yasushi Inoue Literature
Museum (Nagaizumi Town)

Yasunari Kawabata’s Nobel Prize for Literature, The Dancing Girl of Izu
Shirobamba, Natsukusa fuyunami, Chronicle of My MotherYugashima Hot Springs

Setting of Shirobamba, Yugashima Elementary School, Yasushi Inoue’s
grave, Place where Yasunari Kawabata wrote and setting of many essays
and works of fiction

Kawakanjo
Burning of Ōmuroyama
Red Cow Legend
Enka songs

A traditional repose of souls ceremony connected with Kanogawa riverflood
Preservation of the form of the scoria cone
Legend of the Ogawasawa mudslide“Crossing Amagi (Amagi goe)”, “Jogasaki Blues”

31

C. GEOCONSERVATION
C.1 Current and Potential Pressure on the proposed Geopark
Due to the Geopark’s proximity to the Tokyo metropolitan area, urban and tourism development are putting pressure on somegeosites and some of the geological heritage. Population and development related pressure have affected the mountains, seas,
ecosystems, and landscapes of the region in the past. Also, as Izu is a prominent tourist destination near the capital city ofTokyo, ongoing mass tourism trends remain a worry; the Geopark must strive to make travel more environmentally friendly andreduce anthropogenic impact on the natural environment.
In addition, the geological and natural heritage face damage from people who do not understand them, such as through theremoval of fossils or plants, or destruction of geological heritage during works to recover from disasters.

C.2 Curent status in terms of protection of geological sites wothin the proposed Geopark
The concept of geological heritage is a holistic one: it unifies all cultural,
landscape, and ecological heritage systems as parts of the planet’s heritage. This
concept allows us to understand that the earth itself, with its land formation andvarious geodynamic processes, provides the basis for all the diversity we see inliving and non-living nature. Therefore, it is important to understand and evaluate
the interrelationships between land, ecosystems and culture, in order to effectively
address the issue of geoconservation. It is also important to evaluate the various
traditional knowledge systems, and tangible and intangible cultural heritage
components, along with the scientific evaluation of natural processes. Theinterrelationship between ecological and social systems has been explored through‘Social-Ecological System’ (SES) research (Berkes et al. 2012). A newer, morecomprehensive ‘Geosystem’ (Gray 2004) concept is now being discussed by manyscholars to unify living nature and non-living nature as an interrelated system. The
key component of the Geosystem approach is ‘geodiversity’—the idea that all thediversity we encounter in life is interrelated as parts of the same planet.
At Izu Peninsula Geopark, there is an ongoing effort to understand theinterrelationship between geological heritage and local society, which is reflectedin the research on and evaluation of the geological heritage that the Geopark has
undertaken. The 2013 Survey of Conservation and Utilization of Natural andCultural Resources, conducted in coordination with the Ministry of theEnvironment, created a database of all types of natural and cultural resources
around the geosites of the Izu peninsula. This database includes information on
intangible heritage and local beliefs.
Based on this documentation, the Geopark is currently drafting a Conservation
Manual. Efforts are being made to make this manual flexible, so that it can
incorporate new research findings and feedback. The idea is to create an‘Adaptive Management’ platform for conservation of geological heritage.

fig. 29 Image of geosystem

Monitoring
Implementation

Plans

SurveyreseachAcademic
research

fig. 30 Adaptive governance cycle

fig. 31 Image of geosite andadjacent nature/culture heritage(left) and database screenshot (right)
32

C.3 Data on the management and maintenance of all heritage sites
C.3.1 The Management of heritage sites
The geosites of the Izu Peninsula Geopark tell a single story, of an area defined by a group of closely connected phenomena.
Several viewpoints have been established within each geosite, with each viewpoint representing one thing to see.
At present, 114 geosites, including those introduced in the previous section, and 313 viewpoints have been defined within the
Geopark. These viewpoints include some that cannot be viewed safely, and others to which access is restricted. Such viewpoints
would not generally be appropriate for inclusion in geotours, but they have been included on the list to support the monitoringand management of the scientifically important locations within the Geopark. In light of this, the viewpoints have been divided
into the four categories given in the table below, based on intended use.
Table 4 Viewpoint categories and details
Viewpoint Type
General access

Limited access

Educational
purposes

Research purposes

Details
These sites can be visited by anyone: tourists, residents or researchers. They pose
little or no difficulty of access, and visitors can get a sense of the geostory of thepeninsula. Website or pamphlet based guidance is available, and explanation
panels are also present in many of these sites.
These sites can be visited by anyone: tourists, residents or researchers. However,some of them are difficult to access or raise some safety concerns. While thesesites can contribute to geotourism, visitors should access these sites accompaniedby geoguides or tour operators.
These sites have particular value for geoscience researchers. There are no or few
access issues, but the significance of the site cannot be easily explained to alllevels of visitors. Information about these sites can be provided by the Geopark if
requested, and is included in the viewpoint manual.
Mainly for research purposes. They have geoscientific value but access isgenerally difficult. The Geopark provides special guidance about these sites on acase-by-case basis.

Number
159

27

105

22
Total 313

These geosites and viewpoints have been recorded as GIS data in order to facilitate management of the many locations. This
database is not fully public, out of concern for the safety of visitors and conservation, but the data is made available to publicbodies that are commissioning construction or conservation projects, to ensure that development does not destroy any of thegeosites or viewpoints.

fig. 32 Geosite/Viewpoint Management Database33

C.3.2 The Conservation and Preservation Management of Geosites
In this section, we will explain the management status of geosites and geological heritage as governed by the following threefactors:i.
Legal protection of geological heritageii.
De-facto protection as result of nature restoration and traditional managementiii.
Geopark initiatives and related schemes.

i. Legal Protection — National Parks Law, Cultural Properties Protection Law, Local Ordinances
The Izu Peninsula Geopark includes a 224 km2 area of the Fuji-Hakone-Izu
National Park. This area is protected under the National Park Conservationlaw (national level). The Fagus crenata forests of the central Amagi highlands,
some of the most valuable indigenous ecosystems, and coastlines are themain parts of this protected area. 132 viewpoints (of 313) are protected under
this law. Among these, 110 viewpoints are subject to ‘Special Zone’ status,
while the Haccho-Ike Pond viewpoint has the ‘Specially Protected Land
Feature’ status. Stringent legal stipulations safeguard these sites frompressures such as development, construction or logging.
In addition there are 750 ‘Cultural Properties’ designated by the ‘Cultural
Property Protection Act’, and 40 are designated as viewpoints. Apart fromthese, there are a number of locations where unique plant colonies or
ecosystem features are subject to special protection status. There are many
instances of historical town landscapes (parts of Shimoda, Atami, Mishima,and Izunokuni cities) and environment-related features (Nagaizumi town)that are protected as cultural properties. Finally, coastal management plans
and forestry plans effectively protect natural features located in these areas.
fig. 33 National park and viewpoints

ii.De-facto protection as result of nature restoration and traditional management
A number of conservation efforts predate the Geopark activity in the area: some of these are nature restoration projects run by
local residents, and there are cases where parts of the natural environment have been traditionally managed as a form of‘commons’—effecting their protection and renewal.
(a) Nature restoration
This type of protection stems from efforts to ‘restore’ natural environments or landscapes that suffered serious deterioration in
the past. While most of these efforts are oriented towards the living aspects of the environment, the overall effect is theprotection of the geological diversity (as ecosystems are important part of geological diversity). A table listing some major
initiatives is given below.
Table 5 Examples of Nature Conservation and Restoration
KakitaRiver(Shimizu Town)

MishimaSpringwater(Mishima City）

Ishibu Rice Terrace(Matsuzaki Town)

1.2 km river entirely generated by springwater from Mount Fuji, important habitat.
The freshwater environment had deteriorated during the years of post-war economic growth, but 40 years of
restoration activity have improved it. Kakitagawa Midori-no Trust, one of the first National Trusts for theenvironment in Japan, played a key part. In 2011, the Ministry of Land, Infrastructure, Transport and Tourism
drew up a plan for restoring the Kakitagawa environment. The site continues to be a focal point for nature
conservation today.
Mishima City has a unique environment: natural springs form little rivers all over the city. Citizens of Mishima,
led by the NPOs Groundwork Mishima and Mishima Yūsuikai, have led an ongoing effort to clean up industrial
pollution and restore the freshwater environment.
This series of rice terraces, 370 in total covering an area of 42,000 m2, is unusual for east Japan. The region isaffected by the aging of society, but locals have made efforts to preserve this landscape, and restore somedamaged paddies. A ‘paddy owner system’ allows urban residents to own and invest in these rice paddies.
Agri-product development, and collaboration with industry and schools are other features. The area’s way ofmanaging natural resources through agriculture has been recognized as ‘good practice’ by the Ministry of theEnvironment.

34

Ishibu Rice Terraces

Springs in Shirataki Park

Kakita River(b) Management as a Local Commons
Traditional landscape management by local societies over generations is another important part of the conservation of theheritage of the Geopark. Some of these practices are geared to securing ‘ecosystem services’ and the renewal of resources (forexample, periodic grassland burning and regeneration), while other practices have philosophical or religious significance. The
result in both cases is the effective protection and renewal of parts of the natural ecosystems, which can be seen as form of‘local commons.’ A number of geosites and viewpoints are associated with this type of protection, and a list of some prominent
examples is given below. This type of traditional management of natural resources also has profound lessons for sustainability.
Table 6 Examples of Traditionally Managed Landscapes
Omuroyama（Ito City）
Mt Misuji(Hosono Plateau, Higashi
izu Town)
Marine Commons

Sacred Groves
Shiranuta-no-Ike Pond
(Higashiizu Town）

Ōmuroyama (581 m asl) is one of the largest scoria cones in Japan. Created through a monogenetic
eruption 4000 years ago, the mountain retains a beautiful pudding-like shape due to a long tradition (700years) of vegetation burning. This prevents large trees from growing; the pampas grass on the mountain
was once used for compost and roofing houses.
Mt Misuji is a gentle highland, a part of the former large volcanic system of Amagi. This plateau wascreated by the collapse of the southeastern slope, and the area is covered in pampas grass. LikeŌmuroyama, periodic cutting and burning of vegetation allow a good look at the landscape features.
The Izu peninsula is bracketed by the two deep bays of Sagami and Suruga. These seas provide habitats
for a very large number of marine organisms. The regional fishing cooperatives have devised traditional
informal resource management techniques such as stipulation of catch amount and no-fishing seasons, inorder to preserve coastal fisheries.
There are many gigantic and old trees in Izu. Most of these were preserved as parts of sacred groves or
shrine forests. This is a very good example of how local beliefs and traditions can help preserve valuableecosystem features.
Shiranuta-no-Ikë pond is a rainwater pond in a naturally hollowed cavity (landslide induced) in the
Kawakubo river basin. The area is within the Amagi volcanoes, which were active 800,000 to 200,000
years ago. The site is surrounded by natural forests and the pond itself is the habitat of the green tree
frog. As the area is hard to access, the environment is effectively secure from human impact.

iii.Geopark Initiatives and Related Schemes
The Geopark has provided an opportunity to re-evaluate the geological heritage of the region. Programs run by the Geopark
have succeeded in creating impetus for the conservation of outcrops and preservation of strata specimens. In addition, thegeopark provides training programs for construction personnel, forestry workers and farmers in the Shizuoka Prefecture. A shortlist is given below.
Table 7 Examples of Geopark Initiatives
Ishiki Pillow Lavaconservation(Nishiizu Town）

An outcrop of an old submarine lava formation (pillow lava) in the Ishiki region of Nishiizu Town is theoldest land outcrop in the peninsula. This outcrop became a focus for conservation after the Geopark was
established. A committee for preserving this outcrop was established in 2012.

Surface peel of outcrop
at Komuroyama (Ito City)

This surface peel was created by Geopark researchers, and the NPOs Machikon Ito and the Ito Historical
Guide Group in March 2012. The original outcrop was discovered during a road construction project,and is now exhibited on the Komuroyama in a space provided by the Tokai Automobiles group. Thissurface peel provides a record of 40,000 years of monogenetic volcanism in the area, and is therefore avery valuable geological specimen.

Training program for civilengineering,
agriculture-forestry,
and technical workers

Many geosites are located in steep terrain, and these are vulnerable to the construction of roadways andcheck weirs. The Geopark Promotion Council provides training for civil engineers, and construction andagroforestry workers in Shizuoka Prefecture in order to minimize construction impact and prevent
damage from lack of knowledge. New construction activities are expected to address these concerns. The
training program has continued for three years now, and has succeeded in expanding the awareness ofgeological heritage among these workers.

35

OtherIn addition, there are various maintenance, trail management and garbage removal programs that help the Geopark to maintainits heritage.
Table 8 Other Notable Conservation Activities
Cleaning of seabed(Minamiizu Town）

The NPO Izu Mirai Juku is engaged in seabed cleaning with the support of divers and locals. Efforts are
ongoing to evaluate marine landscapes.

Nature research by
citizens

There are many citizen groups that engage in informal research on the natural environment. A good example
is the Atami Shizen Gakko, an NPO in Atami City that undertakes various observation, survey, andexperience based activities to evaluate the local natural environment. Snorkeling, marine classrooms, andobservation cruises are notable activities.

Socioculturallandscapes

Many historical artifacts and cultural landscapes are preserved in Izu. Some of these are registered as culturalmonuments under the relevant laws. Many such artifacts are related to the geological heritage. Mishima
Taisha Shrine (Mishima Daimyojin, a fire deity) and Kakisaki Bentenjima Shrine (Ryūjin, a sea deity) are
examples from local beliefs. There are many literary reliefs and plaques commemorating famous writers
who visited Izu in or around geosites. There are also examples of preservation of historic buildings orobjects.

D. Economic Activity and Business Plan
D.1 Economic activity in the proposed Geopark
D.1.1 Characteristics of Local Industries
Industries in the peninsula can be divided into two broad zones: the northern part enjoys good traffic infrastructure, while thesouthern part is relatively rural and scenic. The Tokaido Shinkansen (Bullet Train Line), and the Tomei and Shin-Tomei
Expressways (Highways) are major traffic arteries that connect the northern region to urban hubs like Tokyo, Yokohama andNagoya. The area is only 1 hour by train from Tokyo, and due to the presence of abundant water, manufacturing industries haveflourished in the region. The area has also been developed as a suburban commuter hub for people working in the Tokyo
metropolitan region.
The central and southern parts of the peninsula are famous as tourist destinations, and attract a lot of tourists throughout the year.
For this reason, tourism is also the biggest industry in the peninsula. Services industries account for 69.4% of employment,
higher than the national average of 66.5%. If the northern region is excluded, service industries account for over 70% of
employment, with tourism providing a particularly high proportion.
Table 9 Industrial workers and employment rate
City/Town

Total working
population

Primary
industry
workers
population

Secondaryindustry
workers
population

Tertiary
industry
workers
population

Tertiary
sectoremployment
percentage
population

Numazu City
Atami City
Mishima City
Ito City
Shimoda City
Izu City
Izunokuni City
Higashiizu Town
Kawazu Town
Minamiizu Town
Matsuzaki Town
Nishiizu Town
Kannami Town
Shimizu Town
Nagaizumi Town

100,487
18,04754,80232,277
11,863
17,07924,569
6,961
3,927
4,330
3,578
4,280
18,554
16,072
20,323

2,818
286
1,230
810
566
1,129
1,361
595
517
499
256
249
705
191
455

30,9432159
15,173
4,312
1,519
3,928
6,347
849
535
560
626
919
5,294
5,084
7,261

64,58915,102
37,181
26,207
9,630
11,84816,562
5,503
2,862
3,204
2,691
3,102
12,404
10,536
12,495

64.3
83.7
67.8
81.2
81.2
69.4
67.4
79.1
72.9
74.0
75.2
72.5
66.9
65.6
61.5

Total

337,149

11,66785,509233,916

69.4

36

D.1.2 Tourism
Tourism to the Izu peninsula is primarily supported by its hot springs. In Japan, with its many volcanoes, people have made useof hot springs since ancient times to refresh their bodies and minds, and bring themselves back to full health and vigor.
Nevertheless, the number of tourists staying at hot spring resorts has shown a long-term decline, and Izu is no exception.
Despite this, over 10 million people stay in the candidate area every year. We aim to increase consciousness of environment
preservation of local residents and touristsby Geopark and to preserve fromdestruction of heritages due to overuse.
In 2009, inspired by the changing needs ofincreasingly diverse tourists, the people ofthe Izu peninsula started to formulate anddevelop the Geopark, aiming to take pridein what was truly good in the area, and,while preserving it, share it with visitors ina sustainable way. As this process advanced,
the Izu Geopark Promotion Council wasestablished in 2011. The 2014 Tourism
fig. 35 Changes of the number of staying guests
Basic Plan of Shizuoka Prefecture includes
the Geopark as a major focus for the future
development of tourism.

D.1.3 Agriculture, Forestry, and Animal Husbandry
The Izu peninsula is mostly mountainous. As a result, apart from the Tagata plain in the north and narrow strips of land in thevalleys, land suitable for rice agriculture is limited. Many local farm products make use of the soil conditions of the gentle
slopes of quaternary volcanoes. Notable products from the eastern part of the Tagata Plain, and southern and western extensionsof the Hakone volcanic area, include potato, radish, watermelon, and shiitake mushroom. Kannami watermelon and Mishima
vegetables are among the well-known local brands from these areas.
Satsumas (tangerines) are cultivated on the mountainsides facing the sea. Dairy farming is popular in the Tanna and West
Amagi areas. Horseradish (wasabi) cultivation is practiced on the areas of quaternary volcanoes that are cleft and partiallyeroded by natural agents. The wasabi plantations cover full streams at places, and intensively use the spring water to cultivate
the crop.
Flower cultivation with the help of the warm climate and ‘hot-spring melon’ farming with the use of geothermal heat are someother notable farming activities. Daisies and carnations are notable among the cultivated flower varieties. The Agriculture
Research Institute of Shizuoka Prefecture has recently started a program of cultivating 11 traditional vegetables of the peninsula
as local alternatives to imported vegetables.

Sunlight dried radish at
Hakone flank

Horseradish farm in
IkadabaWest Amagi Plateau

37

Flier of traditional
vegetables

D.1.4 Fisheries
The deep Suruga and Sagami troughs and the overlying bay waters are rich fishing grounds, yielding catch of a very large
variety of shallow marine and deep marine fish. The spider crab, the largest crab species in the world, is caught off the coast of
Heda cape in Numazu on the west coast. Off the east coast, the Kinmedai (Beryx splendens) is caught widely and products suchas canned Kinmedai are popular. The Geo-don (Geopark seafood dish) is a specialty of the Ito City Fishing Cooperative: avariety of fish are caught by lowering a fixed net, and served fresh on a rice bowl. This type of catch involves anticipation of
tidal patterns and understanding of geological properties of the coast.
Fisheries are managed sustainably through two main mechanisms. The first is legal, in which the country carries out regularscientific surveys of stocks to assess sustainability, and the country and prefecture issue licenses and quotas. The second isthrough voluntary management by local fishing cooperatives.

D.2 Existing and Planned Facilities in the proposed Geopark
D.2.1 Central Facility
In April 2016 the Izu Peninsula Geopark Museum “GEORIA” was opened as the based of operations for the Geopark. It is used
to provide information to visitors, as a base for educational activities, and to support researchers.
GEORIA serves as a hub, providing information and the results of academic research to all the visitor centers, and gathering
information about each region within the park from those visitor centers in turn. It also gathers information about other
Geoparks, both within Japan and across the world.
A researcher is permanently based here, and in addition to the display space, it also houses a library and other educational
facilities, the Bureau offices, and a base for guides. It also has the facilities to collect and manage specimens (stone cutters etc),
and the displays are under constant revision as it supports both internal and external researchers.
The aim is make GEORIA a place where people interested in the Geopark can become involved in its management and build
links with one another, so that they can build the Geopark together.

Elementary School Students at
GEORIA

Tour Design Workshop

Exhibition RoomThis facility is also used forcontact between students.
The picture to the left shows
local high school students
using GEORIA to introduce
the region to visiting highschool students from the USA.

38

D.2.2 Provision of Visitor Centers
This Geopark covers a wide area, and visitors can enter from many directions. Further, geosites and accommodation are widely
scattered within the Geopark. In such a situation, GEORIA would not suffice to distribute information by itself. Thus, theGeopark aims to establish one visitor center in each of the administrative regions (the 15 towns and cities) within the Geopark,each of which will provide information on the surrounding area. At present, 13 of the centers have opened.
While the visitor centers and GEORIA serve different functions, they also form a network of information exchange, ensuringthat visitors to any region of the Geopark can be offered somewhere to enjoyably learn about the area. Further, the Geopark
aims at a system that allows visitor feedback to be shared between all the centers.

Visitor Center

Nagaizumi

already open

Mishimaopen within a few years

Izunoheso

GEORIAGEORIA
Ito Port

NumazuKoganezaki

Ito
Amagi
Higashiizu
KawazuMatsuzaki

ShimodaMinamiizumachi

fig. 34 Location of visitor centers

D.2.3 Guidance and Interpretation Panels
Bilingual (Japanese and English) geo-interpretation panels bearing simple
explanations of the origin of geosites have been set up throughout the park forvisitors and to support geotours. These panels have been set up while working withlocal authorities, companies and NPOs to ensure that they work well with existing
tourist information panels. By the end of March 2014, 100 panels had been set up in
85 locations. The content and design of the panels is decided under the supervision of
the Promotion Council’s researchers, taking account of local historical records andthe opinions of guides. The interpretation panels are made to have a common andeasy-to-understand design throughout the area, and have QR Codes linking back to
the Promotion Council’s website, encouraging access to further information.

Example of interpretation panel at
Asahidaki viewpoint. The panels provide
information not only on geology but also
on history and culture.

39

D.3 Analysis of geotourism potential of proposed Geopark
Geotourism in the Izu peninsula can perhaps be said to have begun in the 1990s, when NPOs and the local Education
Committee in Ito City in the east of the peninsula invited Professor Masato Koyama of Shizuoka University to lead educational
activities about volcanoes. However, at that time the activities were almost entirely confined to Ito City.
During the process of the establishment of the Izu Peninsula Geopark Promotion Council and of training geoguides with a view
to being recognized as a Japanese Geopark, a wide variety of geotours came to be carried out across the peninsula.
In 2014, the Promotion Council set its Basic Plan, and now operates the Geopark in accordance with that plan. In constructing
the plan, a web-based questionnaire was implemented among 350 local residents and responses about the awareness of andhopes for Geopark activities were analyzed. A workshop was subsequently conducted to exchange information between
Geopark personnel and local people. 100 people participated in this workshop, including local residents, administrative workers,
traffic system employees, guides and high school students. The results of the questionnaire and the workshop are discussed
below.

D.3.1 Geotourism Strengths









It is possible to witness different types of volcanism — submarine volcanoes, terrestrial volcanoes, and monogenetic
volcanoes — resulting from the tectonic motion of three plates around the peninsula. Izu’s position at the boundary of
three plates makes it a unique location on the planet.
Due to its relatively warm climate, the Geopark can be visited throughout the year. Geotours take place all over the
peninsula, across the four seasons.
Izu was a favorite among writers of modern times due to its hot springs. The area is one of the most well-known
hot-spring destinations of Japan, attracting 37 million visits (including day trips) per year. Walking trails and toilets are
well-managed, and touring the peninsula is possible with minimal trouble.
There are a number of ecotourism activities, as well as interesting local varieties of tourism combining the geological
heritage with such things as hot springs, literary tours, local cuisine, and marine sports.
70% of the respondents were hopeful that the Geopark would have a positive effect on tourism promotion and 80% were
hopeful that the Geopark would have positive effects on nature conservation.
The establishment of GEORIA has created a general natural history museum.

fig. 35 Web questionnaire results

D.3.2 Geotourism Weaknesses
Only 30% of the respondents were aware of the Geopark’s various activities, though 50% responded that they had heard
about the Geopark in some manner. This leaves ample room for further popularizing the Geopark among locals.
Lack of geoguides who can communicate in foreign languages.

40D.3.3 Ongoing Activities and Future Vision
Based on the findings of the survey and the discussion at the workshop, the following three areas of activity are seen to benecessary.

a. Attracting Visitors to Geotours
In addition to creating Geopark fans who visit the Geopark as their main
destination, it is necessary to attract other types of visitors to the Geopark
using a diverse range of strategies.
With regard to Geopark fans, the Promotion Council currently collects
information about geotours and Geopark events from the member local
authorities, companies, and geoguides, and distributes this information
through its website and monthly email newletter, classified by the month ofthe event. A system of registered supporters has also been established. If aregistered supported attends multiple tours or events, they may receive a
special bonus, and this scheme has increased the number of repeat visitors. In
Workshop for master plan
addition, the NPO Machikon Ito runs a series of tours over the course of a year.
This event has a membership system, and is aimed at people who areinterested in geoscience, with a particular focus on the Izu peninsula. There are 10 events over the course of a year, of which
one is a bus tour to another Geopark in Japan. Through learning about other regions, participants gain a renewed appreciation of
their home area, and this event is not only preparing the ground for receiving new fans, but also energizing the Geopark
network within Japan.
In order to draw in people who have visited the area for other regions, guidance panels are being set up at places that draw
many people, such as the “Michi no Eki” (local centers for people arriving by car) or other tourist spots. Further, training
courses for accommodation staff are conducted at GEORIA, and many articles are published in travel magazines.
b. Improving Residents’ Readiness to Welcome Tourists
In order for geotourism to expand in an area, local residents must have a good understanding of geotourism. Many lecturers anddemonstrations are organized by the Promotion Council, cities/towns, and geoguides to popularize the Geopark amongresidents. The number of such lectures, explanation meetings, demonstrations and study-meets reached 538 as of March 2016.
A total of about 22,500 people have participated in these events.

Publications (left),
Bilingual「Geo IZU」
application(right)

Local media, such as newspapers, have also helped to drive the spread of understanding of the Geopark. The Shizuoka Shimbun
and Izu Shimbun newspapers have been particularly helpful. The official guidebook to the Geopark, “Boken Hanto Izu e
Yokoso!” (“Welcome to Izu, Peninsula of Adventure!”), was published in cooperation with Shizuoka Shimbun, as was the “Izu
Peninsula Geopark Trekking Guidebook”. The newspaper is introducing examples of how the geological environment of thearea impacts people’s lives and work in its continuing “Living with the Earth” series. Similarly, Izu Shimbun has run acontinuing series on the Geopark over the last few years, and introduced the attractions of the Izu Peninsula Geopark from avariety of angles.

41

c. Multilingual Support
As tourism diversifies, group tours from Asia form a high proportion of general foreign tourists in the Izu peninsula. On theother hand, the number of individual Western tourists is also increasing, particularly in southern areas of the peninsula aroundShimoda. Geotourism, from the perspective of the preservation of geological heritage, landforms, and ecosystems, is primarily
targeted at individuals, rather than groups.
The Geopark has Japanese, English, Chinese, and Korean websites. Geopark maps and DVDs have been available in Japanese,
English, Chinese (mainland Putonghua and Taiwanese versions) and Korean since 2013. In March 2014, the Geo-Izu
smartphone application was released. This application targets individual tourists, and is available in Japanese and English. The
application features 12 videos running simultaneously on the screen, and it directs the user to the routes to geosites. The
Geopark will strive to implement special walking tours for foreigners that introduce aspects of geology as well as Japaneseculture, by collaborating with travel agencies that specialize in conducting international tours.
In March 2016, the park made a video targeting individual foreign tourists, and introducing activities such as kayaking, trekking,and diving, by which they could experience the beautiful geological heritage and natural environment of the peninsula. This
video was extremely well received, and the Promotion Council is now working with local businesses and tour companies toensure that people can easily participate in such geoactivities.

D.4 Overview and policies for the sustainable development
D.4.1 Geotourism and Economy
a. Geotours
Many geotours are conducted by various organizations across the peninsula. These tours have different objectives. Since theestablishment of the Geopark Promotion Council, and up to the end of March 2016, a total of 779 geotours were conducted by
the Promotion Council and officially recognized geoguides. These tours attracted total of around 30,000 participants. Geoguides
also conduct tours on their own, or collaborate with other organizations to design tours. The sightseeing cruise company
Dogashima Marine operates geosite cruise tours of 50 minute duration every Saturday; geoguides provide explanations of sites
on this tour. More specialized tours include photo-tours of geosites, hiking tours from visitor centers, bicycle and sea-kayak
tours, and walking tours.
If sustainable tourism is to be realized, it is necessary to train geoguides, develop souvenirs and foods that can be made in thelocal area, and conserve the geosites. Goods and guide training will be covered later, but steps are also being taken to conserve
popular geosites. For example, at Ōmuroyama, it is only possible to ascend the mountain by a chair lift, and signs have been
erected to stress the importance of preserving the form of the scoria cone. The Promotion Council will continue to work closelywith guides and local residents to ensure that conservation and tourism reinforce one another.
b. Product Development
One of the major attractions of the geopark is a variety of products developed by the
locals. The ideas behind these products and their unique sales strategies reflect theinnovativeness of the local people. The most famous product is the Geo-gashi(Geological sweets), and detailed information about these is provided in a later
section. Others include Geopark bread, and ‘Lava Georock’ candy, all of which are
inspired by geosites or landscapes. Pottery modeled on geological landforms isanother notable local product.
The Geopark visitor centers are actively involved in promoting and selling geo-gashi
Geopark related pamphlets
and other Geopark related products as souvenirs. Attractive geosites, geotours or
Geopark related products are also frequently featured in the programs aired on local
cable television channels.
The Geopark is also positively committed to promoting local agriculture, fisheries orprocessed food products such as spring-fed wasabi horseradish and eel, seafood fromthe deep trenches, and vegetables grown in the volcanic soils. In addition to items
that are directly related to the geology of the land, we are committed to promoting
traditionally famous food products like the seaweed of Matsuzaki or Shio-katsuo(salted bonito) as attractions of the Geopark, and incorporating them into tours.
Geopark bread

42

Sand-spit plate (left)
Actual sand-spit (right)

c. Geoguides
The training of geoguides is a key part of Geopark development because these guides show the attractions of the land to visitors
and promote education and geotourism. A geoguide training program has been run by the Geopark every year since 2011 (since2013, the training program has required an enrollment fee), and every year around 50 people take the training. The current
system trains potential geoguides through a series of lectures and field demonstrations and conducts a test that includes
simulation of field guiding after 2 months. In the five years to March 2016, 179 geoguides successfully completed this training.
In 2012, the Izu Peninsula Geoguide Organization was established by certified geoguides. This is a voluntary organization andit helps geoguides to cooperate among themselves. The organization provides a platform for geoguides with knowledge about
different areas to communicate and develop guiding skills that can be used across the peninsula, conduct emergency rescue
drills, and develop other related guiding skills. Further information about their activities is given later.
A program to develop ‘Geoguide-associates’ began in 2013. This is mainly aimed at nature guides who also want to introduce
some aspects of the Geopark. It is currently not possible to organize lectures or training trips for these guiding associates, but
the program will have the effect of expanding the use of the Geopark to other areas of nature tourism. A notable development
has been the establishment of the ‘Ito Geomarine Club,’ which conducts geo-snorkeling and geo-diving for diving enthusiasts.
Geoguides played a major part in the 11 geotours held after the “7th All-Japan Geopark Conference”, held in the Izu peninsula
in October 2016. The guides led various types of tour, including hiking, cruising, and kayaking, while Ito Geomarine Club
organized snorkeling expeditions. Elementary school geoguides also helped, and in all 380 people participated in the 11
geotours.

D.4.2 Geo-education
In order to achieve long term sustainable economic development, it is important to educate the next generation about the
Geopark. Along with this children’s education, adult education about natural disasters such as earthquakes, volcanoes, storms,
and flooding is important. Moreover, such knowledge must be transmitted effectively and disaster response measures must be
developed. The section below introduces some important education and natural disaster response efforts of the Geopark.

a. Geoscience Education
Izu Sogo High School has incorporated the Geopark into its educational activities since the very first days of the park, startingeven before the Geopark was admitted to the Japanese Geoparks Network. It was the first prefecture administered school togain UNESCO School status, and was recognized for its active curriculum of geopark-related activity. The Sogo High School
science division prepares geosite leaflets and fliers, and provides special lecturers for elementary school students. The school
children are also involved in guiding geosites with local support. Geopark education is mandatory for the 2nd year students
enrolling for general education, and in October 2016 around 240 pupils visited the park for study. The opening of GEORIA hada strong positive effect on the Geopark’s educational activities.
Matsuzaki High School runs collaborative learning programs with Izu Sogo High School. Geosite trips and conservation
activities are undertaken by students at this school. They have already started collaboration with locals to help in conservation
activities and foster Geopark related products. Further, they participated in the APGN2015 Symposium, in September 2015,
giving presentations on their activities.
The Ito High School Arts Section developed a birds-eye view representation of the land created by the lava flow from the Izu
Tobu Volcano Group. Panels of this view were made and distributed to elementary and middle schools in the area. This project43

was the result of a collaboration between the school and the local Rotary Club, and there is evidence that initiatives such as thisare helpful in deepening the interaction between schools and local residents.
It is also important that teachers also have a good understanding of the Geopark and the geology of the land. The Geopark
Promotion Council Bureau provides expert support for a volcano experiment toolkit and data about past disasters. Guidance isprovided to school teachers who are interested in geological science and natural disaster prevention. In this way the geopark is
conducting various educational outreach activities. Further, when an educational contact meeting was held in May 2016, many
schools expressed a strong interest in the Geopark, and at the All-Japan Geopark Conference in October, many high schools
gave poster presentations about their activities.
Recently, study of the Geopark has started to develop in elementary schools, some of which visit GEORIA, and the Promotion
Council is responding by sending its researchers to give classes in schools.
In addition, the Geopark runs booths and exhibitions at various local events with the support of geoguides. Simple experiments
and quizzes are arranged for children and their parents who visit the booths. In this way, the Geopark aims to popularize
geoscience among visitors. In August 2013, the ‘Earthquake-Volcano Summer School for Children’ was organized in Shimoda
and Minamiizu (the southern part of the peninsula). A total of 33 children from different parts of Japan participated.

Tour by Izu Sogo High School

Birds eye view of landscapeChildren summer schoolb. Disaster Mitigation Education
Geoparks are places to enjoy the earth’s heritage, but they are also places where visitors can learn about past natural disasters.
Education about such disasters allow us to assimilate knowledge gained from the past and prepare ourselves to respondeffectively in the case of any future disaster. Thus, this type of education helps to develop local level disaster-preparedness.
The Izu Peninsula is a land of active volcanoes (the Izu Tobu Volcano Group), steep mountains, and heavy rainfall, so the riskof a natural disaster striking the region is high. The Geopark runs a variety of disaster preparation programs as a key part of its
activity. We make efforts to teach people to see the evidence of past natural disasters in the geological structure of the landthrough the interpretation panels and geotour contents. Remains from past natural disasters and disaster mitigation
infrastructure are also featured in our geosites. Such measures are helpful for spreading natural disaster awareness more directly.
While adults are also very interested in disaster mitigation, the Geopark is utilized in disaster mitigation education forelementary school children in Minanmiizu Town, and geoguides serve as teachers.

D.4.3 Geo-heritage
Geoparks are places to conserve geological heritage, but they are also places where local societies can use that heritage forsustainable development. We have provided detailed information about conservation in Section C, and here we talk aboutsustainable utilization of the geological heritage.
As geological heritage is a matter of local pride, it is utilized in the various tours and learning activities in the Geopark area.
Natural landscapes and ecosystems provide the basis for the livelihood of many people, especially for those in the coastal areas.
The Geopark promotion council runs many types of programs such as awareness programs for the general public, humanresource development (geoguide training and collaboration with schools), surveys, and research programs. In addition, theGeopark is committed to promoting sustainable resource use by local communities. Such conservation and usage must be basedon academic studies.
In 2012, a survey of volcanic gas release at Teishi Sea Knoll off the Ito coast was conducted in collaboration with the Center for
Integrated Research and Education of Natural Hazards, Shizuoka University. In 2013, Dr. Nemesio Perez from the CanaryIslands visited the area. We hosted a joint lecture by Dr. Perez and Dr. Motoo Ukawa of Nihon University about continuing44undersea volcanism. At that time, we provided support for Dr. Perez’s field survey. Further, as described earlier, the Geopark
provides support for young researchers conducting studies connected with the peninsula. In the future, the Geopark will provide
research results for public use through its academic activities.

D.5 Policies for community empowerment in the proposed Geopark

HarmfulHelpfulThe local governments of the Izu
Internal origin
External origin
peninsula came together in April
Strength
Opportunity
2013 to create the “Izu Peninsula Short distance from Tokyo
 Traffic infrastructure development
Grand Design”, and now follow
 Warm and comfortable climate
 World heritage designation (Nirayama
common policies in certain fields.
 Natural resources are abundantReverberatory Furnaces) Tourism and lodging facilities
 Haneda International Airport, Shizuoka
This Grand Design included a SWOT
 History and literature influence
Airport development
analysis of the peninsula, where Local brands with long history
 Development of Asia and increase of
tourism is the main industry, and a
tourists
collective pledge was made to makeWeakness
Threatthe Geopark a ‘leading project’ for Internal communications not ideal  Natural disasters
regional development. The pledge
 Traffic network issues
 Decline of tourism industry
called for increased collaboration
 Natural disasters
 Transport network change
between different areas of the Depopulation and aging( Access improvement to other tourist spots)
peninsula, based on the concept of a
 Large scale tourist facilities near Tokyo
common heritage of a beautiful yet attimes dangerous nature. Planning
fig. 36
analysis from Izu Peninsula Grand Design
documents
fromdifferent
administrative units feature Geopark related aspects, and this raises the hope that the Geopark will be a key to tool for local
development in the future. Within that, there are particular hopes for the Geopark’s role in responding to natu
ral disasters, and in disaster mitigation education.
In 2012, the Volcanic Disaster Prevention Council was set up to monitor the Izu Tobu Volcano Group and design effective
responses in the case of an emergency. This council is currently preparing evacuation plans and other related emergency
responses. The disaster management plans of Shizuoka Prefecture, Ito City and Izu City clearly mention that the relevant
administrative units will liaise with the Izu Peninsula Geopark Promotion Council and disseminate information about volcanism
to tourists and concerned parties. The Promotion Council is a member of the Volcanic Hazard Prevention Council and various
programs to involve the Geopark in disaster prevention are currently
being designed and implemented.
The involvement of women in the Geopark is also moving forward.
There are 179 people who have taken and passed the guide training
courses run by the Geopark Promotion Council, and about 40% ofthem are women. The Izu Geoguide Association is currently led by awoman, and the geoguides responsible for the Geogashi and
Geo-Ikebana described later are all women. The flexible anddistinctive ideas of these women are a cornerstone of the Geopark.

D.6 Policies for public and stakeholder awareness in the proposed Geopark
As the Geopark is about local people, geoguides who know about the geological heritage of the land are a most valuable asset
for the Geopark. They take a central role in promoting the Geopark within and outside its immediate locality. Several innovative
efforts by our geoguides to promote the Geopark have attracted widespread attention.
The Geogashi Ryokodan (Geological sweets travel group), a guide group consisting of two local women, has developed novel
sweets that replicate landforms and landscapes of the Geopark. The sweets are made with local ingredients and each package
includes a Japanese and English description of the landform or landscape. This brand is now famous, and the activities of
Geogashi Ryokodan are often featured in the media. They were also a big hit with visitors from Asia at the APGN international
meeting. The Geogashi Ryokodan is involved in designing geogashi tours, joint product development with local schools, and45

assisting with the development of products at other Geoparks, and has a stand at regional science events across the country.
Their involvement in activities that capture the ideals of the Geopark is continuing to develop.
A geoguide based in Mishima designed a unique Ikebana flower arrangement style that depicts geosites. Ikebana is a traditional
Japanese flower art, and is also an intangible heritage. An exhibition of this Ikebana in Mishima in December 2013 attracted
347 visitors in one day. This Geo-Ikebana was also displayed to the 1,000 participants in the 7th All-Japan Geopark Conference
held in Izu in October 2016.
The All-Japan Conference is the largest Geopark-related event in Japan. The aims of holding the conference in Izu were,
naturally, to support Geoparks across Japan, and also to increase the interest of people living in this region in Geoparks. The
conference encouraged interest inGgeoparks from many angles, including the appeal of geology and landforms, researchpresentations that involved children, experience events, and food, the blessings of the earth. In cooperation with the Japan
Geopark Network, we also welcomed 10 people representing UNESCO and three southeast Asian countries seeking to registerand develop Geoparks, and as well as holding meetings with Japanese Geopark representatives, we provided tours with
geoguides, and further raised the interest in Geoparks of both the visitors and local residents through an appreciation of ourdifferences and unique features.
Local businesses are becoming increasingly attached to the Geopark. The Izukyū Cable Network and Izukyūko group (cable car
and railway) have started to run ‘geo-trains’ with the Geopark logo and geosite photographs. Further, Tokai Automobile, whichruns the local scheduled buses, is helping to raise local awareness of the Geopark by including its logo in buses and on bus
stops.
The Promotion Council Bureau is directly responsible for several initiatives, such as special lectures for residents and local
schools, the Geopark Aptitude Test (2,147 people have taken this simple web-based test over 5 years), demonstration booths invarious programs, and providing lectures or demonstrations upon request.

GeogashiGeoikebana
Traditional flower arrangement

Geotrain guidancein local train

Cliff Edge Project
Art project by local artists.
Two arrow shaped objects located on bothsides of the fault show the direction of the
movement of Tanna fault.

South-pointing arrow in“Chokoji” temple

North-pointing arrow in“KURUBUSHI-BASE” art gallery

46

E. Reasons for Seeking Recognition as a UNESCO Global Geopark
The Izu Peninsula Geopark is committed to the ideals of a Geopark, to contributing to the conservation of the nature, history
and culture of the area, and to promoting tourism, local development, education, and the mitigation of natural hazards. The
Geopark is engaged with other Japanese and international Geoparks, and we aim to bring benefits to our area as well as toenrich Geoparks in general in the process. As the peninsula is located close to Tokyo and is popular as a tourist destination, Izu
Peninsula Geopark has a unique opportunity to spread Geopark awareness among a large number of people, and to develop a
new value system for the Japanese people, who live on a geologically active and dynamic land.
We are motivated to reach new goals of research, education, disaster mitigation, and conservation of geological heritage byimplementing global-level Geopark activities and communicating the activities of geoguides and local residents to the world.
We have the following three contributions in mind as a UNESCO Global Geopark.

The first contribution is to bring the heritage of the Izu peninsula, a land of globally important geological
heritage, to the network.
The Izu peninsula originated as a submarine volcanic massif in the southern ocean. It collided with Honshū and created new
landforms through volcanism and crustal motion due to the tectonic motion of the Philippine Sea plate. Izu’s geological history
and ongoing volcanism and crustal motion allow us to gain insight into the planetary processes of land formation and evolution.
The Izu peninsula in this sense is a unique place in the world, with many features not otherwise represented in the Geopark
network. In all areas of the peninsula evidence of this geological heritage can be found. The geological story of the peninsula
can be followed in the following order: ancient submarine volcanism in a deep marine environment followed by transition tosubmarine volcanism in a shallow marine environment, collision with Honshū, assimilation to continental crust and terrestrial
volcanism, and finally the ongoing monogenetic volcanism (itself rare in Japan). The foremost aim of our Geopark is to provide
knowledge about the process of evolution of the earth’s crust through our geological heritage.

The second contribution is the value system of living in a geologically active location, the utilization ofgeological heritage, and advanced disaster mitigation initiatives.
The people of Izu have used volcanic gifts such as hot springs, horseradish plantations that use the abundant springwater of thecentral Amagi mountains, and the spectacular natural scenery of seaside cliffs as an economic base for local society. But on theother hand, Izu has suffered from serious natural disasters. Earthquakes and volcanic eruptions due to ongoing crustal motion,
flooding and landslides due to heavy rainfall and steep terrain—these are some typical examples of natural disasters in thisregion. A Geopark in this area is therefore a tool for raising natural hazard awareness among locals, by extending understandingof nature and the cause of natural hazards. Several structures such as a flood bypass channel in a flood-prone river, a massive
tidal surge lock-gate with an observation facility, and volcanic activity observation apparatus, are all used in Izu geotours.
We believe that by promoting our region as a Geopark, and by communicating local efforts to use the benefits of nature andrespond to natural hazards we can reach out to people who suffer from similar disasters and share useful information.

The third contribution is that at our geopark there are ongoing efforts for sustainable development driven
by local society.
Whatever landscape appears before our eyes has a special meaning, and the world appears a different place when we are able tounderstand the deeper significance of our everyday experiences. The local people of the Izu peninsula have started to feel asense of wonder through knowing more about their Geopark, and learning about the earth in the process. The Geopark allows
local inhabitants to re-evaluate the landscapes they are naturally familiar with, and Geopark activities have begun tocommunicate the heritage of Izu to visitors and future generations. The Geopark contributes to a deeper sense of pride among
local people, and Geopark activities are successfully cultivating a common resolve to develop Izu in a sustainable way, paying
close attention to the characteristics of the land and preserving cultural traditions that stretch back generations.
Yasunari Kawabata, the Nobel Prize winning author, described Izu as ‘a huge park in itself’. We, as Izu Peninsula Geopark, willcontinually strive to develop this ‘huge park’ in a sustainable manner.
Then, we will share the experiences and knowledge gained through the above efforts to the Geopark network and aim to further
increase the value of Geopark.

47

Opening lines from “Introduction to Izu” by Yasunari Kawabata
People say Izu is a land of poets.
Historians say Izu is a miniature of Japan.
I add: Izu is a land resembling the south.
Izu is an art gallery that has every possible landscape of mountains and sea in its possession.
The whole Izu Peninsula is one large park...
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