Guide Book

The 6th International
Symposium of International
Geoscience Programme
IGCP Project 608“Cretaceous Ecosystems
and Their Response to
Paleoenvironmental Changes
in Asia and the Western Pacific”

November 12-14, 2018
Khon Kaen-Udon Thani-Bueng Kan-Nakhon Phanom-Kalasin

The 6th
International Symposium ofInternational Geoscience Programme
IGCP Project 608
Excursion Guidebook, 12-14 November 2018
: Geology of the Northeastern Thailand 2018

II Pre-Symposium Geology Excursion Guidebook

Preface
The excursion guide book was prepared for the field trip to the northeastern          Thailand during November 12-14, 2018. The aims of this excursion is the fulfillment forthe 6th International Symposium of International Geoscience Programme IGCP Project 608
on Cretaceous Ecosystems and their Response to Paleoenvironmental Changes in Asiaand the Western Pacific that has been held at Charoen Thani Hotel, Khon Kaen, Thailand
during 15-17 November 2018.
This guide book was described 9 stops of visit, including not only geological sites
but also attractive places for tourists. The authors hope that all participants would achieveand exchange their knowledge and experience on geology of the northeastern Thailand
during the excursion.

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Table of Contents
II
III
IV
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25
27
29
31
33
35
37
39
41

:: Preface:: Content:: Excursion programme:: The story of Khorat Plateau:: Dinosaur on the Khorat Plateau:: The excursion stops• Stop 1 Dinosaur excavation pits no. 3• Stop 2 Phu Wiang Fossil Research Centerand Dinosaur Museum• Stop 3 Chao Pu Lup Shrine• Stop 4 150 Million Years Shell Museum• Stop 5 Wat Jetiyakhiri (Wat Phu Thok)• Stop 6 Dinosaur Footprints• Stop 7 Wat Phra That Phanom• Stop 8 Huai Huat Reservoir• Stop 9 Sirindhorn Museum

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PRE-SYMPOSIUM EXCURSION PROGRAM

Khon Kaen-Udon Thani-Bueng Kan-Nakhon Phanom-Kalasin

DAY 1: 12/11/2018 Khon Kaen-Udon Thani
Time
Programme
08.00 Depart from the Rachawadee Hotel, Khon Kaen, Thailand
08.00 – 09.30 Travel to Phu Wiang National park, Khon Kaen Province
09.30 – 10.30 Stop 1: Dinosaur excavation pits no. 3 at Phu Wiang National park,
Khon Kaen Province
10.30 – 10.45 Travel to Phu Wiang Fossil Research Center and Dinosaur Museum
10.45 – 11.00 Coffee break at Phu Wiang Fossil Research Center and Dinosaur Museum

11.00 – 12.00 Stop 2: Visit the Phu Wiang Fossil Research Center and Dinosaur Museum,
Khon Kaen Province
12.00 – 13.00 Lunch at Phu Wiang Fossil Research Center
13.00 – 14.45 Travel to Chao Pu Lup Shrine and coffee break in the bus
14.45 – 15.45 Stop 3: Chao Pu Lup Shrine
16.00 – 16.45 Stop 4: Visit to the 150 Million Years Shell Museum, Nong Bua Lam Phu Province
17.30 – 19.30 Dinner at VT Namnueng restaurant, Udon Thani Province
19.30 – 20.00 Check in at Brown House Hotel, Udon Thani Province

DAY 2: 13/11/2018 Udon Thani-Nakhon PhanomTime
Programme
07.00 Depart from the Brown House Hotel, Udon Thani Province
07.00 – 10.30 Travel to Wat Phu Thok and coffee break in the bus
10.30 – 12.30 Stop 5: Type section of Phu Thok Formation at Wat Jetiyakhiri (Wat Phu Thok)
12.30 – 15.00 Travel to Tha Uthen District and have packed lunch in the bus
15.00 – 16.00 Stop 6: Study on the Dinosaur Footprints and trackways at Dinosaur Footprintsite at Tha Uthen District, Nakhon Phanom Province
16.00 – 17.00 Check in at The River Hotel, Nakhon Phanom Province
17.00 – 18.30 Sightseeing river bank on both Thai and Laos sides by Mekong River cruise
18.30 – 21.00 Dinner at The River Hotel, Nakhon Phanom ProvinceV IGCP 608

DAY 3: 14/11/2018 Nakhon Phanom-Khon KaenTime
Programme
08.00 Depart from The River Hotel, Nakhon Phanom Province
09.00 – 09.45 Stop 7: Visit Wat Phra That Phanom, Nakhon Phanom Province
09.45 – 12.00 Travel to Huai Huat Reservoir, Phu Pha Yol National Park, Sakon Nakhon Province
12.00 – 13.00 Lunch at Phu Pha Yol National Park
13.00 – 14.00 Stop 8: Study on Phu Phan Formation at Huai Huat Reservoir, Phu Pha Yoi National Park, Sakon Nakhon Province
14.00 – 16.00 Travel to Sirindhorn Museum, Kalasin Province and coffee break in the bus
16.00 – 17.30 Stop 9: Visit Sirindhorn Museum (the biggest dinosaur museum, dinosaur
conservation and excavation pit in Southeast Asia), Kalasin Province

17.30 – 18.30 Dinner at Sirindhorn Museum, Kalasin Province
18.30 – 20.00 Depart from Sirindhorn Museum to Charoen Thani Hotel
20.00 Check in at Charoen Thani Hotel, Khon Kaen Province1 Pre-Symposium Geology Excursion Guidebook

The sTory ofKhorat Plateau

Based on the geology of Thailand (DMR, 2014) most of the continental rocks crop out in the northeastern region of Thailand. Detailed studies of the Mesozoic rocks began in 1921, when exploration forcoal and petroleum was carried out to supply the Royal State Railway’s energy requirements. In 1951,
Sethaputra et al. gave the name Khorat Series to all Mesozoic rocks found in Thailand.
Chaleechan and Bunnag (1954) divided the sedimentary rocks of the northeastern region into 4groups, from older to younger, the Phu Kradung Group and Phra Wihan Group of Triassic, and the Phu
Phan Group and an unnamed group of Rhaetian to Jurassic age.
In 1964, Ward and Bunnag (1964) named the Khorat Group and seven formations, from older toyounger, the Nam Phong Formation (Rhaetian), the Phu Kradung, Phra Wihan, Sao Khua, Phu Phan and
Khok Kruat Formations of Jurassic to Cretaceous and an unnamed unit of Cretaceous to Early Tertiaryage. In the same year, Iwai and Asama (1964) divided the Khorat Group into only six formations by combining the Phra Wihan and Sao Khua Formations together as the Phra Wihan Formation. Their sequenceof older to younger rocks was the Nam Phong (Rhaetian), Phu Kradung, Phra Wihan, Phu Phan, Ban Na
Yo Formations of Jurassic to Cretaceous, and Lomsak Formation of Late Cretaceous age.
In 1967, Gardner et al. (1967) named the Maha Sarakham Formation for the unnamed formationof Ward and Bunnag (1964).
In 1971, Bunopas (1971) named the Nam Pha Formation for a unit of rocks which may be equivalent to the Huai Hin Lat Formation. He also combined the Nam Phong and Phu Kradung Formations
together as the Phu Kradung Formation.
In 1973, Iwai (1973) reported dolomitic limestone close to Phu Kradung mountain and included
this unit in the Phu Kradung Formation.
Hite (1974) made numerous studies of the evaporates occurring on the Khorat plateau and in Lao
PDR, leading to the exploitation of potash deposits in Thailand and Lao PDR (Hite and Japakasetr, 1979).
In 1978, Chonglakmani and Sattayarak (1978) combined the Nam Pha Formation with the Huai
Hin Lat Formation as the Huai Hin Lat Formation. In the same year, Sattayarak and Suteethorn (1979)
informally designated the Phu Thok Formation for the unnamed formation of Ward and Bunnag (1964)
above the Maha Sarakham Formation of Gardner et al. (1967).
As part of a study of red beds in the northeast, Maranate and Vella (1986) dated formations in
the Khorat Group by paleomagnetic methods. Heggemann et al. (1991) dated Phra Wihan Formation to
be Middle Jurassic based on fossils of leaves and arthopoda. In 1991, a report of correlation between
surface stratigraphy and seismic profiles was made by Sattayarak et al. (1991). In the following year,
conclusion of structural geology of the northeast was made by Thanomsap (1992).
Mouret et al. (1993) described rocks in part of Phu Phan mountain range in the vicinity of Waritchaphum district, Sakon Nakhon Province.

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Structural geology of the northeast was studied by Chuaviroj (1997) who showed that there wereat least three episodes of tectonism in the region. Paleoenvironment, paleoclimate and fossils of Cretaceous were interpreted using criteria found in the rocks of the Khorat Group.
Brief history of paleontological studies is as follows.
In 1963, Kobayashi et al. (1963) named some Khorat Group fossils, especially the bivalves.
In 1980, Buffetaut and Ingavat (1980) studied fossil vertebrates found in rocks of the Phu Kradung
Formation along the road from Nong Bua Lamphu to Udon Thani Provinces. New species of crocodile
was found and named as Sunosuchus thailandicus. Paleogeography of Southeast Asia during Mesozoic
was also describe. After finding of crocodile fossils, Buffetaut (1981) continued studying of fossil of thesame era in the northeastern part of Thailand. Hahn (1982) made stratigraphic study of the rocks in the
Khorat Group. After all, Buffetaut (1983) has compiled all data and written report about vertebrate fossils of Thailand.
Sattayarak and Suteethorn (1983) conducted geological survey and published a geologic map
scale 1:500,000 of the northeastern part of Thailand based on the previous data and reports. Later on,
Buffetaut and Ingavat (1984) wrote a report about small Late Jurassic carnivorous dinosaur of the northeastern region. Suteethorn and Jarnyaharn (1985) made a geologic map, scale 1:250,000, Sheet Roi Et.
This map contained more details than the previous 1:500,000 scale map. This map served as basis formore detailed mapping in other areas.
Buffetaut and Ingavat have made a report involving Mesozoic vertebrate fossils in the northeastern part in 1986 (Buffetaut and Ingavat, 1986).
Heggemann et al. (1991) studied leaf fossil and animal fossil of Arthopoda and concluded that ageof the Phra Wihan Formation was Middle Jurassic.
After making more vertebrate study, Buffetaut and Suteethorn (1993) have compiled all available
data concerning dinosaur and other vertebrates in Thailand and published.
In 1994, new species of herbivorous dinosaurs and bivalve fossils indicated Early Cretaceous werediscovered by Martin et al. (1994) and Meesook (pers. Comm). Meesook et al. (1995a and 1995b) studied
bivalve fossils in the Sao Khua Formation which indicated Cretaceous. They also made a conclusion ofCretaceous rocks in the northeastern Thailand in the same year.
In 1996, Racey et al. (1996) studied the Mesozoic rocks in the northeast emphasis on palynomorphs. He concluded that most of rocks in the Khorat Group was described as Early Cretaceous.
Buffetaut et al. (1997) reported about new findings of Jurassic and Cretaceous dinosaur in thenortheast. Correlation between dinosaurs found in Thailand and in other counties were made and reported by Buffetaut and Suteethorn (1998).
The oldest dinosaur (Triassic) was found in the Nam Phong Formation by Buffetaut et al. (2000). It
was named as Isanosauras attavipachi.
In general, rock sequences of the Khorat Group in Khorat plateau comprise 9 formations, i.e. fromolder to younger rocks, the Huai Hin Lat, Nam Phong, Phu Kradung, Phra Wihan, Sao Khua, Phu Phan,
Khok Kruat, Maha Sarakham, and Phu Thok Formations. These formations unconformably overlie Triassic
and Permian rocks and underlie Tertiary and Quaternary deposits. However, the Nam Phong Formation

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Figure 2 Geological Map of the Khorat Plateau, northeastern Thailand showing the excursion
stops (from geological map of Thailand 1:1,000,000 scale; version 1999)

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Figure 3 Explanation of Geological Map of southwest the Khorat Plateau and the eastern Thailand

5 Pre-Symposium Geology Excursion Guidebook
and the Maha Sarakham Formations were not exposed in area of Phu Si Than wildlife sanctuary and its
vicinity, a part of Phu Phan mountain range.
In area north of Phitsanulok Province and west of Loei Province, red beds overlaying the Maha
Sarakham Formation were found in many locations. The red beds can be divided into 2 formations i.e.
Khao Ya Puk Formation and overlying Phu Khat Formation. Khao Ya Puk is equivalent to Phu Thok Formation on the Khorat plateau.
The Khorat Group was dated as Upper Triassic to Cretaceous-Lower Tertiary as determined by fossil assemblage of vertebrates (Buffetaut et al., 1997), bivalves (Meesook et al., 1995) and palynomorphs(Racey et al., 1994, 1996).
Rocks in the Khorat Group generally were exposed by folding structures as anticline and syncline
on the Khorat plateau and its vicinity except in the southwestern part of the plateau, the rocks were
exposed less due to flat terrain with overlying thick soil.

Triassic Rocks

Triassic formations are described from older to younger as follows:

Huai Hin Lat Formation
General information: The Huai Hin Lat Formation is the lowermost continental formation (Iwai etal., 1966). The formation was named after the type section in Huai Hin Lat stream where it crosses the
Chaiyaphum-Chum Phae-Lomsak road at km 252. Later, Bunopas (1971) named the lowermost formation of the Khorat Group as Nam Pha Formation but this formation was combined into the Huai Hin Lat
Formation by Chonglakmani and Sattayarak (1978) because of their lithological similarity and equivalentage.
Stratigraphic relations: An unconformable contact was found between the Huai Hin Lat Formation and underlying the Nam Duk Formation and other Upper Permian rocks. A gradational contact was
found between the Huai Hin Lat Formation and the overlying the Nam Phong Formation (Chonglakmani
and Sattayarak, 1979).
Lithology: The Huai Hin Lat Formation at its type section consists of two units. The lower unit
is 200 m thick comprising basal conglomerate with some limestone interbedded (Figure 1). The upper
unit is 50 m thick comprising gray sandstone and mudstone with interbedded dark gray calcareous mudstone. The dark gray calcareous mudstone became white when weathered. In other areas, this formation
was composed of basal conglomerate with interbedding of sandstone, mudstone, dark gray mudstoneand some gypsum.
Thickness and distribution: At its type section the formation is 250 m thick. Elsewhere its thickness varies between 100-400 m. The rocks of this formation are widely distributed along the western
rim of the Khorat plateau including Wang Saphung district, Tha Li district of Loei Province, Si Chomphu
district, Chum Phae district of Khon Kaen Province, Khon Sarn district, Phu Khiao district of Chaiyaphum
Province and Muang district, Lom Sak district, Lom Kao district of Phetchabun Province.
Paleoenvironment and paleoclimate: Study of the stratigraphy, lithology and fossil assemblages of the Huai Hin Lat Formation indicates deposition in an environment of flat and rolling terrain
at foot of mountains. Some sediments were deposited in small water pools containing high carbonate
concentration. The climate varied from slightly humid to semi-arid.

6 IGCP 608

Stratigraphic column of the rocks on the Khorat Plateau

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Fossil and Age: Iwai et al. (1966) reported
a floral of Neocalamites sp., Equisetites sp., Cladophebis sp., Clathropteris cf. meniscoides Brongnairt and Pterophyllum sp. indicating a Rhaetian(Triassic) age. The turtle Chelonian ruchae wasfound in dark gray limestone at Ban Khon Sawan,
Si Chomphu district, Khon Kaen Province (Broin
et al., 1987). Other vertebrates from the northeastern region include the toad; Cyclotosaurus cf.
posthumus Frass (Ingavat and Janvier, 1981), phytosaur crocodile Mystriosuchus sp. (Buffetaut and1
Ingavat, 1982; Buffetaut et al., 1993), and the fish
Ceratodus cf. szechuanensis (Martin and Ingavat,
1982). Palynomorphs (spores and pollen) include
Ovalipollis luzensis, Cycadopites carpenticri,
Alisporites sp., Zebrasporit fimbriatus, Camerosporites sp., Concavisporites luzensis and Verrucosporites
sp., dated as Carnian-Norian (Haile, 1973). The conchostracans Euestheria mansuyi Kobayashi, E. thailandica Kobayashi, E. buravasi Kobayashi, Khoratesteria macroumbo Kobayashi, Metarhabdosties (?), andAsmussia symmetrica Kobayashi (Kobayashi, 1975) were also found. Age of the Huai Hin Lat Formation istaken to be Late Triassic (Carnian-Norian, possibly extending into the Rhaetian).

Nam Phong Formation
General information: Ward and Bunnag (1964) named the Nam Phong Formation for rocks at
type section along the Lam Nam Phong river and Lam Phong Go in Phu Kradung district, Loei Province.
Stratigraphic relation: A gradational contact is found between the Nam Phong Formation andthe underlying Huai Hin Lat Formation (Chonglakmani and Sattayarak, 1979). Interbedding of Nam Phong
red beds and Huai Hin Lat conglomerate was found between the two formations and the base of the
Nam Phong Formation was defined as the base of reddish brown conglomerate.
Lithology: Ward and Bunnag (1964) divided the Nam Phong Formation into three units. The lowest unit consists of reddish brown siltstone, sandstone, and mudstone. The rocks in this unit are easily
weathered. The middle unit comprises sandstone and conglomerate containing pebbles of vein quartz,
chert, reddish brown siltstone and igneous rocks. Clasts up to 5 cm diameter are found but their average
size is less than 2 cm. The upper unit is composed of reddish brown shale, mudstone, and siltstone.
Thickness and distribution: Thickness of the Nam Phong Formation at its type section is 1,465
m. Elsewhere it varies between 100-1,500 m. The formation is widely distributed along the western edgeof the Khorat plateau in parallel with the Huai Hin Lat Formation and is found in Wang Saphung district,Tha Li district of Loei Province, Si Chomphu district, Chum Phae district of Khon Kaen Province, Khon
Sarn district, Phu Khiao district of Chaiyaphum Province, Muang district, Lom Sak district, Lom Kao districtof Phetchabun Province, Muang district, Si Bun Rueang of Nong Bua Lam Phu Province, and Phu Wiang
district, Nong Rua district of Loei Province.
Paleoenvironment and paleoclimate: Lithology, stratigraphy and fossils found in the rocks of
the Nam Phong The formation is believed to be deposited in the alluvial fan and then changed to me-8 IGCP 608
andering river system having channels and flood plains in semi-arid paleoclimate.
Fossil and Age: Ward and Bunnag (1964) found some teeth-like fossil along Huai Khlong Bong
stream on Sura Narai road in Chai Badan district, Lopburi Province. Maranate (1982), determined ageof the Nam Phong Formation to be Lower Jurassic, based on his paleomagnetic study. Buffetaut etal. (1995) found a large bone of a prosauropod dinosaur. Early dating of the formation was as Rhaetian. However, the age of the formation in Chaiyaphum, based on the oldest dinosaur Isanosaurus attavipachi, was revised to be Ladinian to Rhaetian (Buffetaut et al., 2000). Based on the fact that the Nam
Phong Formation overlies the Norian Huai Hin Lat Formation, the age of the Nam Phong Formation isregarded as Rhaetian.

Jurassic Rocks

Jurassic rocks are described from older to younger formations as follows:

Phu Kradung Formation
General information: Ward and Bunnag (1964) named this formation after Phu Kradung Mountain
where the type section is in Lam Phong Go stream where it is crossed by a track leading to the top of
the mountain.
Stratigraphic relation: From data of seismic profiles contact between the Phu Kradung Formation and the underlying the Nam Phong Formation is unconformable (Sattayarak et al., 1991). However,
because of similarity in the stratigraphy, paleoclimate and environment of deposition of both formations, they might be expected to be conformable. The Phra Wihan Formation conformably lie on the
Phu Kradung Formation.
Lithology: Ward and Bunnag (1964) described the Phu Kradung Formation at its type locality ascomprising of lower beds of calcareous siltstone intercalated with 1-5 cm thick beds of limestone andthe upper beds comprising of grayish brown siltstone (Figure 2). The upper beds underlie white massive
sandstone of the Phra Wihan Formation. Elsewhere the formation consists of reddish purple siltstone,
mudstone, sandstone, and conglomerate. Calcrete nodules, caliches and nodular silcretes are found on
top of mudstone. Beds of light gray sandstone with 5-10 m thick are locally intercalated.
Thickness and distribution: The thicknessof the Phu Kradung Formation at its type sectionis 1,001 m. It varies between 800-1,200 m elsewhere. The formation is widely distributed along
the western rim of the Khorat Plateau in parallel with the Huai Hin Lat Formation and the Nam
Phong Formation. It is found in Wang Saphung district, Tha Li district of Loei Province, Si Chomphu
district, Chum Phae district of Khon Kaen Province, Khon Sarn district, Phu Khiao district of Chaiyaphum Province and Muang district, Lom Sak district, Lom Kao district of Phetchabun Province. It
is also found in other parts of the Khorat plateau,2such as in Phu Phan mountain range, Phu Wiang
mountain range, Muang district, Si Bun Ruang of

9 Pre-Symposium Geology Excursion Guidebook
Nong Bua Lam Phu Province, Phu Wiang district, Nong Rua district of Loei Province, Loeng Nok Tha of
Yasothon Province, Pho Sai district of Ubon Ratchathani Province, Ta Phraya district of Sa Kaeo Provinceand Khlong Yai district of Trat Province.
Paleoenvironment and paleoclimate: Lithology, stratigraphy and fossils found in the Phu Kradung Formation indicate a depositional environment of meandering rivers with high energy level of current along the river channels. Later, the environment of deposition changed to be in flood plains, fresh
water lakes and ponds in semi-arid paleoclimate (Meesook, 2000).
Fossil and Age: Fossils found in the Phu Kradung Formation include the freshwater bivalves Unio
thailandica Hayami, Unio sp., and Neomiodon (?) khoratensis Hayami. These fossils were found at Wat
Pa Re Rai, Khon San district of Chaiyaphum Province, on the Mae Nam Chern river bank, Ban Nong Pa,
Phu Khiao of Chaiyaphum Province and on southern side of road between Khon Kaen Province andChum Phae district, Ban Khok Soong, Chum Phae district of Khon Kaen Province. Fossil of pleleosaur
Teeth of pleseosaur marine reptiles was found on road side between Udon Thani and Nong Bua Lamphu Provinces. At the same location, Buffetaut and Ingavat (1980) found the teeth and lower jaw of the
freshwater crocodile Sunosuchus thailandicus. Palynomorphs (spores and pollen) include ?Ballosporites
sp., Calamospora sp., Classopollis striatus Madler, Ballosporites hians Madler, ? Ovalipollis sp., and Cyclotriletes subgranulatus Madler are recorded. Classopollis sp., Cyathidites sp. and Ballosporites hians
Madler were found on tract to the top of the Phu Kradung mountain.
Many different types of vertebrates are found in Phu Si Than wildlife sanctuary and Ban Na Pung,
Khamcha-i district, Mukdahan Province (1:50,000 scale map, Khamcha-i district map sheet 5842-II). The
fish Lepidotes was discovered at Ban Pon Sawang, Khao Wong district of Kalasin Province (1:50,000
scale map, Kuchinarai district map sheet 5842-III), 15 km west of Phu Si Than wildlife sanctuary. Teethof the sauropod dinosaur in Ban Khok Sanam, Kham Muang district of Kalasin Province are different
from Phuwiangosaurus sirindhornae (Martin et al., 1994) found in the Sao Khua Formation. This latter issimilar to fossil of Jurassic dinosaurs from China (Buffetaut et al., 1997), such as genus Euhelopus andMamenchisaurus. Thus, dating of the Phu Kradung Formation is based on a variety of vertebrate fossils
including fish scales, turtleplates, temnospondyl amphibian, crocodilian teeth and theropod and sauropod dinosaur teeth.
Based on palynomorph evidence, the Phu Kradung Formation should be dated as Late Jurassic to
Early Cretaceous (Racey et al., 1994, 1996). In this case, sediments of Jurassic age are 1996). In this case,sediments of Jurassic age are missing and there is no reason to explain why deposition of sediments had
stopped during Jurassic, a period of 60 Ma. However, discoveries of vertebrate and invertebrate fossils in
the formation pinpointed the age of the Phu Kradung Formation to be Middle to Late Jurassic.

Jurassic-Cretaceous Rocks

Jurassic-Cretaceous formations are described from older to younger as follows:

Phra Wihan Formation
General information: Chaleechan and Bunnag (1954) named the Phra Wihan Formation for agroup of rocks exposed at Khao Phra Wihan, Cambodia. Later, Ward and Bunnag (1964) used the term
Phra Wihan Formation in a more restricted sense as the old formation was now divided into the Phra
Wihan Formation, Sao Khua Formation, and Phu Phan Formation. Ward and Bunnag (1964) also studied
the Khorat Group on a track up to the top of the Phu Kradung mountain where they found rocks of the10 IGCP 608
Phra Wihan Formation in the Sam Hak area to consist of two beds with total thickness of 56 m.
Stratigraphic relation: Contacts between the Phra Wihan Formation and the underlying Phu
Kradung Formation and the overlying Sao Khua Formation are generally conformable. The conformable contact between the Phra Wihan Formation and the Phu Kradung Formation can be seen in Phu Si
Than wildlife sanctuary on highway no. 2287 between Khao Wong and Dong Loung Seismic  profiles innear vicinity confirmed the conformable contact between the two formations. The sequence boundary
between the Phra Wihan Formation and the Phu Kradung Formation was caused by transition of environment of deposition from meandering river to braided river systems. Contact between the Phra Wihan
Formation and the Sao Khua Formation was not seen as it was covered by soil. However, conformablecontact was presumed and environment of deposition reversed from braided river systems to meandering river in slightly humid to semi-arid conditions.
Lithology: The Phra Wihan Formation comprises well sorted, rounded, fine- to coarse-grained,
pale yellow sandstone, thin-bedded siltstone, mudstone and conglomerate. Most of the detrital grains
in sandstone are quartz (Figure 3).
Thickness and distribution: Generally, thickness of the Phra Wihan Formation is 100-250 m. At
the Phu Si Than wildlife sanctuary it is 30 m on average, ranging between 20-50 m. Distribution of this formation is similar to that of the Phu Kradung Formation, earlier described. However, it is best exposed in
Kham Muang district, Somdet district, Huai Phueng district of Kalasin Province, Kaset Sombun district of
Chaiyaphum Province, Kantharalak district of Si Sa Ket Province, Ta Phraya district of Sa Kaeo Province.
Paleoenvironment and paleoclimate: Lithology, stratigraphy, and fossils found in the Phra
Wihan Formation indicate a depositional environment of braided streams and occasional meanderingrivers in slightly humid conditions (Meesook, 2000). Thick sandstone beds, occurred as high cliff were
deposited in braided stream environment, whereas thinner sandstone beds were deposited in meandering rivers. Intercalations of siltstone and mudstone are found mainly in the latter sandstone beds whichshow little resistance to weathering which reduced them to small hills.
Fossil and age: Fauna fossil Dicotyledon was found in Phra Wihan Formation in Phu Wiang, northof Chum Phae District of Khon Kaen Province. It was dated Jurassic to Early Cretaceous. Palynomorphs
include Cyathidites sp., Classopollis sp., Ballosporites hians, Lycopodiacidites sp., Calamospora sp.,
Monosuleites sp., ?Ballosporites sp., Cyclotriletes
subgranulatus MADL, Minutosaccus sp., Chasmatosporites sp., and cf. Anulatizonites indicatinga Late Triassic to Early Jurassic age which is thesame age as pollen in the Phu Kradung Formation(Hahn, 1982).
Dinosaur foot print are found in sandstonesof the Phra Wihan Formation in several locations,such as Phu Faek, Na Khu District of Kalasin Province (1:50,000 scale map, Kuchinarai District sheet
5842-III). This location is at 25 km west of Phu Si
3Than wildlife sanctuary and exposes a foot printof a carnivorous dinosaur 45 cm long. Using Thul-

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born’s equation (Thulborn, 1990), the height of this dinosaur is calculated as 2 m up to its hip. Small dinosaur foot prints are found in other areas, such as at Hin Lad Pa Chad, Phu Wiang District of Khon Kaen
Province (Buffetaut and Suteethorn, 1993). These foot prints cannot be used for dating the rocks, however palynomorphs in the Phra Wihan Formation indicate the age to be Early Cretaceous (Racey et al.,
1994, 1996). Arthropod and plant fossils were interpreted as Middle Jurassic (Heggemann et al., 1991).
In conclusion, the age of the Phra Wihan Formation is regarded as Middle Jurassic to Early Cretaceous.

Cretaceous Rocks
Sao Khua Formation

General information: Ward and Bunnag (1964) named the Sao Khua Formation from Sao Khua
stream north of road between Udon Thani and Nong Bua Lam Phu Provinces. The formation comprises
60-70% of reddish brown siltstone withgray bands and 30% of fine to very fine grained pink sandstone
with some conglomerate. Other rocks in the Sao Khua Formation are mudstone, reddish brown andgreenish gray calcareous conglomerate, and white sandstone.
Stratigraphic relation: The Sao Khua Formation has conformable contacts with the underlying
Phra Wihan Formation and the overlying Phu Phan Formation.
Lithology: The Sao Khua Formation consists of cycles of reddish brown sandy mudstone withinterbedded siltstone, fine- to medium-grained sandstone and conglomerate. Caliches, calcrete nodules
and thin-bedded and nodular silcretes are included in the formation (Figure 4). The color of this formation is generally reddish brown. Beds of calcretes
and silcretes are thicker than those found in the
Phu Kradung and the Khok Kruat Formations.
An Exploration Project for uranium deposits at Phu Wiang national park, Hahn (1982) divided the Sao Khua Formation into three units.
Unit A is the uppermost unit. It comprises
red to violet shale and siltstone, fine- to medium-grained grayish purple sandstone.
Unit B mostly composed of fine- to medium-grained light gray sandstone with some shaleand conglomerate. Plant fossils, copper ore anduranium were found in this unit.
Unit C consists of red to purple shale andsiltstone with interbedded reddish purple, pink
and dark red sandstone.
In comparison with other upper formationsof the Khorat Group, the Sao Khua Formationshows the most lateral changes in both lithology
4and thickness. In some locations, the formationis only 60 m thick, elsewhere only pebbly sandstone with interbedded siltstone is found and lo-12 IGCP 608
cally calcrete horizons 3 m thick are interbedded. Calcrete horizons are also found 20-30 m below the
top of the formation, overlying fossiliferous conglomerate.
Thickness and distribution: Generally, the Sao Khua Formation is 200-760 m thick. However, insome locations such as at Phu Phan mountain, Average thickness is 120 m with a range of 50-200 m. The
formation is widely distributed on the Khorat plateau, like the Phu Kradung and Phra Wihan Formations.
Large areas of Sao Khua Formation are found in Phu Phan district (1:50,000 scale map 5842-I), Tao Ngoi
district of Sakon Nakhon Province (map 5842-IV) and Dong Luang district of Mukdahan Province. The
northwestern-southeastern trend of the formation was found located in sheet Amphoe Somdet (5742-II)
and sheet Amphoe Kuchinarai (5842-III). The southernmost occurrence of the formation is found in sheet
Amphoe Khamcha-i (5842-II).
Paleoenvironment and paleoclimate: Based on studies of lithology, stratigraphy, and fossils,
sand and gravels were deposited in meandering rivers and in swamps on the river bank in semi-arid
paleoclimate (Meesook, 2000).
Fossil and age: Occurrences of freshwater naticoid gastropods and marine bivalves Cardinoides
magnus, Mytilus rectangularis and Solemya sp., marine ichthyosaur and plesiosaur were reported by
Ward and Bunnag (1964). Kon’no and Asama (1973) found plant remains of Sphenoptheris goeppati,
dated Late Jurassic to Early Cretaceous. Early to Middle Jurassic pollen and spores include Circulina,
Smooth Triletes, Disaccites, Vitteisporites cf. pallidus, and Ephedripites.
In comparison with the other Mesozoic formations in Thailand, The Sao Khua Formation is themost prolific horizon for vertebrate fossils. The fossils include fresh water hybodont sharks, antinopterygian fishes, turtles, crocodiles, theropodand sauropod dinosaurs and bivalves. The crocodile foundin this formation is Goniopholis phuwiangensis (Buffetaut and Ingavat, 1980). The theropod dinosaur is
Siamotyrannus isanensis, which is believed to be an ancestor of tyranosaurids (Buffetaut et al., 1996).
Fossil of ostrich-like dinosaur was also found. Martin et al. (1994) found the sauropod dinosaur Phuwiangosaurus sirindhornae in many locations where the Sao Khua Formation outcrops. At present, vertebrate
and invertebrate fossils were found in many locations of Sakon Nakhon Province, such as Phu Pha Yol,
Phu Phan district (1:50,000 scale map, sheet Amphoe Tao Ngoi 5842-IV). Study of palynomorphs in the
Sao Khua Formation indicated an Early Cretaceous age. Fossils of continental vertebrates were foundin the Phu Wiang area and include dinosaurs, crocodiles, turtles and fishes (Ingavat and Taquet, 1978;
Ingavat and Buffetaut, 1981; Racey et al., 1994, 1996; Buffetaut et al., 1997) and bivalves (Meesook etal., 1995a). These fossils also indicate an Early Cretaceous age. Thus, all the avidence confirms an Early
Cretaceous age for the Sao Khua Formation.

Phu Phan Formation
General information: The type section of the Phu Phan Formation is at Phu Pha Phung in the
Phu Phan mountain range, Khao Wong district of Kalasin Province.
Stratigraphic relation: Contacts of the Phu Phan Formation with both the underlying the Sao
Khua Formation and the overlying the Khok Kraut Formation are conformable.
Lithology: The Phu Phan Formation consists of medium- to coarse-grained light gray sandstone.
Some sandstones grade into thick beds of conglomerate with large planar and trough cross-bedding (Figure 5). Pebbles consist of white quartz, gray and green volcanic rocks, and gray, dark gray, reddish brown,
black, light gray and green chert. Detrital grains are well rounded but poorly sorted. In some areas,

13 Pre-Symposium Geology Excursion Guidebook

5lenses of dark gray shale are found interbedded.
Other lithologies found in the Phu Phan Formation
are siltstone, shale, conglomerate with calcareous
lens, and reddish brown sandstone.
Thickness and distribution: Generally,
thickness of the Phu Phan Formation is 80-140 m
but this varies due to weathering and erosion. The
coarse-grained sandstone of this formation madeit resistant to erosion and so it always caps highmountains and has dips of less than 100. The Phu
Phan Formation is widely distributed on the Khorat
Plateau, especially along the outer rim of the Sao
Khua Formation, such as in Phu Phan district and
Tao Ngoi district of Sakon Nakhon Province, Nong
Sung district, Kham Cha-i district and Dong Luang

district of Mukdahan Province.
Paleoenvironment and paleoclimate: Based on studies of lithology, stratigraphy, and fossils,
the Phu Phan Formation was deposited in braided streams and occasional meandering rivers in a rather
hot and humid to semi arid paleoclimate (Meesook, 2000).
Fossil and age: No vertebrate remains have been found, but the foot print of a theropod dinosaur occurs on Phu Luang Mountain, Loei Province (Buffetaut et al., 1985a, b). Beds of bivalves are foundin the lowermost part of the formation, but they are broken and abraded having been reworked fromthe Sao Khua Formation. Since the Phu Phan Formation overlies the Early Cretaceous Sao Khua Formation and underlies the Khok Kruat Formation of the same age, then the age of the Phu Phan Formation
should be Early Cretaceous. Dating by palynomorphs confirms this Early Cretaceous age (Racey et al.,
1994, 1996).

Khok Kruat Formation
General information: Ward and Bunnag (1964) named the Khok Kruat Formation from the village
of Khok Kruat in Mueang district, Nakhon Ratchasima Province. Rocks in this formation outcropped at thisvillage and along Thai-American Friendship road.
Stratigraphic relation: Contact of the Khok Kruat Formation is conformable contact between theunderlying Phu Phan Formation which was found in Khong Chiam district, Ubon Ratchathani Province.
The contact is sequencial boundary in a non-marine environment, gradational from braided river tomeandering river systems. A sharp contact between the Khok Kruat Formation and the overlying basal
anhydrite of the Maha Sarakham Formation is found in a drilling well (Hite, 1974; Hite and Japakasetr,
1979). Seismic profiles also confirmed such contact (Sattayarak et al., 1991). Then, it can be infered that
contact between the Khok Kruat Formation and the overlying Maha Sarakham Formation is regarded as
unconformable contact (Figure 6).
Lithology: The Khok Kruat Formation comprises reddish brown, reddish purple sandstone, siltstone, mudstone and conglomerate. Pink, grayish red, pale brown fine-grained sandstone forms thickto massive beds. Some sandstone beds contain pebbles of reddish brown siltstone, claystone, and14 IGCP 608
some quartz. Calcrete nodules and caliche occur
at the top of some mudstones. Gypsum lens andlaminated interbeds of sandstone and siltstonealso occur. Changes in facies produced cycles
of channel conglomerate, channel sandstone,
overbank siltstone and flood plain siltstone andclaystone. Channel conglomerates are locally6absent.
Thickness and distribution: The thickness of the Khok Kruat Formation is generally inthe range of 430-700 m. However, the thickness
at Nam Phung dam is 100 m.
This formation is found in the northeastern region along both rims of basin in anticlinal structure.
This basin is situated in the northern part of Phu Phan mountain range. Phu Phan and Sao Khua Formation also crop out in these locations. The Khok Kruat Formation is found in Phu Phan sheet (5842-I),
and Amphoe Tao Ngoi sheet (5842-IV) of Na Mon district, Huai Phueng district, Kuchinarai district andSomdet district of Kalasin Province, Sakon Nakhon Province, Dong Luang district of Mukdahan Province.
The northwestern-southeastern trend of the formation was located in sheet Amphoe Somdet (5742-II)
and sheet Amphoe Kuchinarai (5842-III).
Paleoenvironment and paleoclimate: Based on studies of lithology, stratigraphy, and fossils,theKhok Kruat Formation was deposited in a meandering river system. Paleoclimate changed from semi arid
at the beginning to arid at the end (Meesook, 2000).
Fossils and age: Kobayashi (1964a) described the freshwater bivalves Nippononaia mekongensis, Trigonioides, Plicatounio, Paranodonta (?) khoratensis from Ban Na Yo, Mueang district, Mukdahan
Province and dated them initially as Early Cretaceous, but revised this to Late Cretaceous (Kobayashi,1968). Kobayashi’s material came from the Ban Na Yo Formation which regarded as a synonym of the
Khok Kruat Formation. Ichthyosaur teeth were found on Sura Narai road, Thep Sathit district, Chaiyaphum Province by Ward and Bunnag (1964). Teeth of freshwater hybodont sharks, other fresh water
fish,  and a theropod dinosaur were found on the road side at Ban Khok Kruat, Muang district, Nakhon
Ratchasima Province. Red sandstone of the Khok Kruat Formation at Nam Phung dam, Sakon Nakhon
Province contains the fresh water bivalves Plicatotrigonioides (?) subovalis Kobayashi, Pseudohyaia (?)
sp., Nippononaia carinate Kobayashi, Niotononaia (Mechongichoncha) subyuadrata Kobayashi, Nippononaia (Mechongichoncha) robusta Kobayashi, Plicatounio namphungensis, and Unio sampanoides, dated
as Early to Middle Cretaceous.
On the Khorat Plateau, fossils of dinosaurs have been found in Khok Kruat Formation for a longtime (Buffetaut, 1983). The first dinosaur fossils were teeth and bones of a theropod, found at Ban Dong
Bang Noi, Chaiyaphum Province. The small ceratopsian Psittacosaurus sattayaraki was more recently
found (Buffetaut and Suteethorn, 1992) and indicates a relationship with fossils from the northern partof Asia (Buffetaut et al., 1989).
In Ban Thung Bun, Si Mueang Mai district, Ubon Ratchathani Province, fragmants of dinosaurbones, turtle plate and fish scales of Lepidotes were found in reddish brown shale, siltstone and con-

15 Pre-Symposium Geology Excursion Guidebook
glomerate. Most of the fossils were found in a conglomerate lens. The dinosaur belongs to the genus
Iguanodon and is the first record of an ornithopod dinosaur in Thailand (Buffetaut et al., 1997). In the
Lao PDR, hadrosaurid dinosaurs were found in red beds at Mueang Phalane in the Savannakhet basin(Hoffet, 1944). Stratigraphic studies indicate that the red beds in the Lao PDR underlie salt beds (Vu Khucand Le Thi Nghinh, 1996). These salt beds are equivalent to the Maha Sarakham Formation in Thailand.
Based on vertebrate fossils, the Khok Kruat Formation was dated between Aptian and Albian in the Early
Cretaceous (Capetta et al., 1990).

Maha Sarakham Formation

General information: The Maha Sarakham Formation was named by Gardner et al. (1967) with
its type section in groundwater well F-34 in Ban Chiang Hian, Mueang district, Maha Sarakham Province.
The hole was drill in 1961. At that time, geologists believed that this location was in the middle of the
Khorat basin. The Maha Sarakham Formation is equivalent to the unnamed formation of Ward and Bunnag (1964).
Stratigraphic relation: Maha Sarakham Formation unconformably overlies Khok Kruat Formation(Sattayarak et al., 1991). It is conformably overlain by the Phu Thok Formation and Khao Ya Puk Formation.
Lithology: The Maha Sarakham Formation comprises interbedded claystone, siltstone and rocksalts. Based on data obtained from exploration for potash deposit and petroleum, it suggested that thisformation should not be included in Khorat Group (Sattayarak, 1983, 1985). Based on data in hands, theMaha Sarakham Formation can be divided into six layers.
1) Basal anhydrite is 0.8 to 3.3 m thick. This unit overlies Khok Kruat Formation on a disconformable contact.
2) Lower Rock Salt is the thickest unit at 437 m, and consists of thick salt beds and potash beds.
3) Lower Claystone is reddish brown in color with scattered green spots and small carnallite andhalite veins. This unit is 35 m thick.
4) Middle Rock Salt contains mostly halite, however, some anhydrite and gypsum are also found.
This unit is 100 m thick.
5) Middle Claystone is the same as the lower claystone unit without kanallite and halite veinlets.
This unit is 40 m thick.
6) Upper Rock Salt is 3 to 65 m thick. No potash was found in this unit.
An upper claystone unit was defined by Ward and Bunnag (1964) above the unnamed unit orMaha Sarakham Formation. This unit consists of claystone with siltstone and sandstone interbedded. An
unconformity beneath this unit excludes it from the Maha Sarakham Formation.
Thickness and distribution: Drill data indicates the thickness of the Maha Sarakham Formation to
be 610 m in the type well. It can be up to 1,000 m elsewhere. Out crops of the formation is widespreadin Sakon Nakhon, Udon Thani, Khon Kaen, Nong Khai, Kalasin, Roi Et, Yasothon, Amnat Charoen, Ubon
Ratchathani, Maha Sarakham and Nakhon Ratchasima Provinces. Salt domes are clearly seen in Ban
Dung district, Udon Thani Province, Ban Mueang district, Sakon Nakhon Province, Borabue district, Maha
Sarakham Province and Phimai district, Nakhon Ratchasima Province.

16 IGCP 608
Paleoenvironment and paleoclimate: Based on studies of lithology, stratigraphy, rock salt, gypsum and anhydrite, the Maha Sarakham Formation was formed by deposition in salty lakes and pondsin an arid climate (Meesook, 2000).
Fossils and age: Paleomorph studies indicated age of the Maha Sarakham Formation to be
Cenomanian (early Late Cretaceous) (Sattayarak et al., 1991).

Cretaceous-Tertiary Rocks
Phu Thok Formation

General information: The Phu Thok Formation was named by Chonglakmani et al. (1979) for
rocks outcropping around the rim of the Udon Thani-Sakon Nakhon basin. The type section is at Phu
Thok Noi, Si Wilai district, Nong Khai Province. Imsamut (1997) studied the formation in the areas of Phu
Thok Noi and Phu Wua and divided this formation into four units.
Stratigraphic relation: Contact between the Phu Thok Formation and the underlying Maha Sarakham Formation could not be seen at the surface. However, core rock from a well at Ban Tha Phra, Khon
Kaen Province indicated the contact between the two formations to be at 391 m depth. In the area of
Ban Nam Kam, Sakon Nakhon Province, a part of Udon Thani-Sakon Nakhon basin, red beds of the Phu
Thok Formation overlie Maha Sarakham salt beds at 98 m depth (Tansuwan and Boonkanpai, 1998).
Lithology: Generally, Phu Thok Formation comprises two types of sandstone interbedded witheach other (Imsamut, 1997). The first type is thick cross bedded reddish brown, fine- to medium-coarse
grained sandstone (Figure 7). The second type is reddish brown to reddish purple very fine grained tosilty calcareous sandstone. Ripple marks are found in the second type of sandstone. The Phu Thok Formation was divided into four units as follows:
Unit A comprises thick-beds of very fine-grained sandstone and silty sandstone.
Unit B consists of intercalation of fine- to coarse-grained sandstone and very fine-grained to silty
calcareous sandstone.
Unit C is composed of medium-coarse tocoarse sandstone.
Unit D is the uppermost unit comprisingsimilar rocks to those of Unit B.
Petrographic study indicated Phu Thoksandstones to be lithic arkose-subarkose.
Thickness and distribution: The Phu
Thok Formation is 205 m thick in the areas of Phu
Thok and Phu Wua (Imsamut, 1997). The thickness varies locally depending on the amount oferosion in each area. The Phu Thok Formation
forms a landscape of rolling terrain with isolated
7hills.
The Phu Thok Formation is extensively distributed in Phu Thok Noi, Phu Thok Yai, Phu Sing,

17 Pre-Symposium Geology Excursion Guidebook
Phu Wua, Phu Lanka and in the rolling terrain of the upper northern region at Pak Khat, Bung Kan, Phon
Charoen, Si Wilai, Seka, and Bung Khong Long districts of Nong Khai Province, Ban Phaeng, Tha Uthen,Renu Nakhon and That Phanom districts of Nakhon Phanom Province, Sawang Daen Din district of Sakon Nakhon Province, Ban Phai district of Khon Kaen Province, and Borabue, Na Chuak district of Maha
Sarakham Province.
Paleoenvironment and paleoclimate: Based on studies of lithology and stratigraphy, the Phu
Thok Formation was deposited from meandering river systems and by wind in a semi arid to arid paleoclimate.
Fossil and age: No fossils have been found in this formation. Paleomagnetic studies indicate an
Early Cretaceous age (Imsamut, 1997), but age of the Phu Thok Formation is presumably Late Cretaceous to Early Tertiary.

Khao Ya Puk Formation
General information: Kosuwan and Chaichalermsak, (1990) named this formation after Khao Ya
Puk along road between Nakhon Thai and Ban Na Mueang, Nakhon Thai district, Pitsanulok Province.
Stratigraphic relation: The Khao Ya Puk Formation conformably overlies the Maha Sarakham
Formation and unconformably underlies the Phu Khat Formation. A conformable contact with the Maha
Sarakham Formation was seen, on well-log data, to be at 150 m depth at Ban Nam Lat, Nakhon Thai district, Phitsanulok Province. The unconformity contact with the Phu Khat Formation is seen along roads
between Chat Trakan district and Ban Bo Phak and between Nakhon Thai district and Ban Phu Khat.
Lithology: The Khao Ya Puk Formation consists of thick-beds of brick red, coarse-grained, wellrounded, rather well sorted sandstone, siltstone, claystone, and reddish brown and reddish purple siltstone. Cross bedding and ripple mark were also found in the rocks.
In the middle part of the sequence, fine-grained sandstone is interbedded with reddish brown tobrown siltstone. Mica is present in the siltstone. Some beds are calcareous. Mud cracks and ripple marks
are found in sandstones.
In the lower part of the sequence, sandstone is interbedded with reddish brown claystone withsome inclusion of gypsum.
Thickness and distribution: Thickness of Khao Ya Puk Formation varies between 200-350 m.
Thickness of the formation found in the Chat Trakan waterfall national park is at least 350 m. Drilling
data at Ban Na Chan, Chat Trakan district, Phitsanulok Province indicated a thickness of 105 m. The Khao
Ya Puk Formation is found in Chat Trakan, and Nakhon Thai districts of Phitsanulok Province, Dan Sai and
Na Haeo districts of Loei Province, Nam Pat and Fak Tha districts of Uttaradit Province.
Paleoenvironment and paleoclimate: Based on studies of lithology, stratigraphy, rock salt, gypsum and animal foot prints found in Chat Trakan Waterfall National park, sediments of the Khao Ya Puk
Formation were deposited in a meandering river system and dry lake with windblown sand in a semiarid to arid paleoclimate. The upper part of the formation indicates that the climate was extremely arid.
Fossil and age: No fossils have been found in this formation. However, foot prints of hoofed
animals were found in cross bedded sandstone. These hoofed animals are assumed to have been living
during the Tertiary. As the Khao Ya Puk Formation overlies the Cretaceous Maha Sarakham Formation, it
should be Late Cretaceous to Tertiary.

18 IGCP 608

Phu Khat Formation
General information: Kosuwan (1990) named this formation for the rocks at Phu Khat Mountain,
Nakhon Thai district of Phitsanulok Province.
Stratigraphic relation: Contact between the Phu Khat Formation and the underlying Khao Ya
Puk Formation is unconformable. The contact between the Phu Khat Formation and overlying rocks is
not seen.
Lithology: The Phu Khat Formation consist of purple brown to brown, fine- to medium-grained,
well sorted, calcareous sandstone with siltstone and claystone interbedded. Purple red, well rounded,
poorly sorted conglomerate was found at the base of the formation. Pebbles in the conglomerate comprise vein quartz, chert, sandstone, siltstone, volcanic rocks and limestone.
Thickness and distribution: The thickness of this formation varies from 150 to over 500 m. The
wide distribution of this formation is similar to that of the Khao Ya Puk Formation. The Phu Khat Formation is clearly recognized in Phu Khat, Khao Lom Yai, Khao Ya Puk and Khao Khat.
Paleoenvironment and paleoclimate: Based on studies of lithology and stratigraphy, sedimentsof the Phu Khat Formation were deposited in a meandering river system and alluvial fan in a semi arid
paleoclimate.
Fossil and age: No fossils have been found in this formation. As the Phu Khat Formation unconformably overlies the Khao Ya Puk Formation it must be younger than the latter, possibly Late Cretaceous to Tertiary.

19 Pre-Symposium Geology Excursion Guidebook

Dinosauron the Khorat Plateau
Systematic study of dinosaurs in Thailand
started 30 years ago by a group of Thai-Frenchpaleontologists searching for vertebrate fossils.
They found a number of dinosaur and other fossils in many Mesozoic horizons. The oldest dinosaur was dated as Late Triassic (approx. 200 Ma).
The youngest one is Middle Cretaceous (approx.
100 Ma). The oldest dinosaur fossil was found in
1992 in the Nam Phong Formation in Phetchabun
Province. It is the end of the issium bone of a prosauropod - plant eating dinosaurs. This dinosaur
can be 8 m long. Its teeth have coarse serrations. It
had a long neck, small front legs, and sharp claws.
In July 1998, a new location was found in Nong
Bua Daeng district, Chaiyaphum Province, providing more information.
The first vertebrate fossil was found in the
Phu Kradung Formation and consisted of the lower
jaw bone of the crocodile Sunosuchus thailandicus(Buffetaut and Ingavat, 1980, 1984). Dinosaurs fromthis formation were found a few years in Kalasinand Mukdahan Provinces. There are four types ofdinosaurs as follows:• Theropod: Big carnosaurs teeth with serrated edge
• Sauropod: Spoon-shaped teeth• Stegosaur: Back bones were found in graysandstone. The back bones of stegosaur are clearly different from other dinosaurs.
• Hypsilophodon: Distinct femur of hypsilophodontid was found.
These fossils were found mixing with crocodile teeth, turtle plates, Lepidotes fish, and fresh
water clams.

u

20 IGCP 608
Cretaceous was the golden period of Thaidinosaurs. Foot prints and bones of dinosaurs
were found in many localities in northeasternregion such as Khon Kaen, Kalasin, Mukdahan,
Sakon Nakhon, Udon Thani, Nong Bua Lamphu,
Chaiyaphum, Nakhon Ratchasima, Loei, Ubon Ratchathani Provinces. Four formations of the Khorat
Group that contained the fossils are listed below
in succession from lower to upper formations asfollows:
The Phra Wihan Formation comprises thickand hard beds of sandstone. Foot prints are foundon the surface of the beds. The foot prints occurred when the sediment on banks of water
courses was still soft. The animals which cameto drink water left their foot prints in the muddy
sediment. They were covered and preserved after
the sediment was lithified. Tectonism and erosion
exposed the preserved foot prints. There are 5 locations in Thailand that dinosaur foot prints were
found, in which 4 locations were found in Phra
Wihan Formation dated at 140 Ma.
• Phu Wiang, Khon Kaen Province: Foot
prints of theropod dinosaur were found. This typeof dinosaur walked on its two back legs. Sixty footprints were found. They are three toes like birds.
• Khao Yai National Forest Reserve, Prachin
Buri Province: Several three toes foot prints were
found on boulders along stream channel by members of nature lover club.
• Phu Faek, Kalasin Province: More thantwenty big theropod footprints were found by
Kalya Singnakhlong and Pachari Waisaen in 1996.
Many tracks were found. It was the biggest andclearest footprint found in Thailand withdimension of 45 cm long and 40 cm wide.
• Phu Kao, Nong Bua Lamphu Province: Morethan twenty medium sized trackway were found.
The Sao Khua Formation dated Early Cretaceous (approx. 130 Ma) is the formation in whichmost dinosaur fossils were found. Three main

Isanosaurus attavipachi : Living in the Late Triassic periodaround 210 million years old, a 12-15 meters long Isanosaurus
attavipachi is the oldest herbivorous sauropod unearthed sofar. It was found in the Nam Phong Formation in Chiyaphum
Province and was named in honor after a former director general of the Department of Mineral Resources (DMR) Mr. Preecha
Attavipach.

Phuwiangosaurus sirindhornae : Named to honor HRH Princess Maha Chakri Sirindhorn of Thailand who has been interested in paleontology, Phuwiangosaurus sirindhornae wasan herbivorous sauropod dinosaur living in herds during the
Early Cretaceous period around 130 million years ago. It measured between 15-20 meters long, had a long neck and tail,and walked on 4 legs. Found in Khon Kaen Province, this giant
plant-eater was a new genus and species of the world.

Siamosaurus suteethorni : The First large carnivore discovered in Thailand, Siamosaurus suteethorni lived in the early
Cretaceous period around 130 million years old. It was 7 meters long and wolked on 2 legs. Siamosaurus suteethorni was
known as a water dwelling fish-eater from its sharp conicalteeth which closely resembled those of crocodiles. It wasnamed after Mr.Varavudh Suteethorn who played an importantrole in the investigation. The fossils were unearthed in khon
Kaen, Kalasin, Chaiyaphum, Ubon Ratchathani, Sakon Nakhon,
Udon Thani, and Nakhon Ratchasima Provinces.

21 Pre-Symposium Geology Excursion Guidebook
types of dinosaur are:• Siamosaurus suteethorni (Buffetaut andIngavat, 1986) is the first dinosaur fossil found in
Thailand. Therefore, to honor Mr. Warawut Suteethorn, the founder, it was named after his family name. It is a large theropod with cone shaped
teeth with groove and ridge like crocodile teeth(Figure 8). It was likely to be a fish eater.
• Phuwiangosaurus sirindhornae (Martin etal., 1994) is the first sauropod found in Thailand.
It was named in honor of HRH Princess Sirindhorn
who is very interested in paleontology. This dinosaur is a medium sized sauropod 15-20 m inlength. It walked on four feet, long neck and tail,plant eater, lived in cluster (Figure 5.33). Bones ofa young sauropod, 2 m long and only 1/2 m tallwere also found.
• Siamotyrannus isanensis (Buffetaut et al.,1996) is the large theropod 6 m in length, strong
and big femur, backbones, hips and tail bone (Figure 5.34). The bone fossils were well preservedin sandstone beds. This theropod belongs to theoldest family the Tyrannosauridae. Therefore, tyrannosaurids presumably began to develop in Asia
and later migrated to the north of Asia and finallyreached North America before becoming extinct.
There are more dinosaur fossils found in the
Sao Khua Formation such as front leg bones andshin bones of Compsognathus, and the fast andagile ostrich Kinnareemimus Khonkaenensis. Thisostrich was a theropod that had no teeth but possibly fed on animals and plants. It is 1-2 m long. A
crocodile Goniopholis, turtle, fish Lepidotes, andfreshwater hybodont shark were found together
with dinosaur fossils.
Phu Phan Formation: Dinosaur footprints
were found on the surface of sandstone beds of
the Phu Phan Formation on Phu Luang, Loei Province in 1985. Fifteen footprints belong to a carnosaur - a large theropod walking on two legs withthree toes. The clearest footprint is 35 cm long.
The step length is 2.8 m. This dinosaur was cal-Siamotyrannus isanensis : This large carnivorous dinosaur
was the oldest Tyranosaur found in the world. Existing in the
Early Cretaceous period some 130 million years ago. It was believed to originally evolve in Asia and then spread to North Asia
North American before becoming extinct. Siamotyrannus isanensis was 6.5 meters long and walked on its 2 huge and powerful legs. Complete fossilized Pubis and Caudal vertebrae ofthe specimen were discovered in sandstones. Siamotyrannus
isanensis was excavated in Khon Kean, Kalasin, Chaiyaphum,
Sakon Nakhon, Udon Thani, and Nokhon Ratchasima Provinces.

Kinnareemimus Khonkaenesis : Excavated in Khon Kaen andKalasin Province, this ornithomimosaur (ostrich-mimic dinosaur)
was from the Early Cretaceous period around 130 million years
ago. Measured 1-2 meters long, Kinnareemimus Khonkaenesis
was a swift and fast-running dinosaur with no teeth, eating bothplants and animals.

Psittacosaurus sattayaraki : A small herbivorous ceratopsian(parrot-beaked) dinosaur of about a meter long, Psittacosaurus
sattayaraki, walked the earth in the Middle Cretaceous period some 100 million years ago. Prehistorically, parrot-beaked
dinosaurs were found throughout central Asia, in Shantung
Province of China, Mongolia, and Siberia. The discovery of thefossils in Thailand, therefore, was concrete evidence that Indochina was already a part of the mainland of Asia since the Early
Cretaceous period. Unearthed in Chaiyaphum Province, it wasnamed after Mr.Nares Sattayarak, the discoverer.

22 IGCP 608
culated to be 1.8 m high to the hip. It could walkwith speed of 8 km/hr.
Khok Kruat Formation: Fossils of the freshwater shark Thaiodus ruchae (Capetta et al., 1990)
were found in the Khok Kruat Formation anddated to be about 100 Ma. Four types of theropod and one type of sauropod were also foundin this formation. Teeth of ornithisian dinosaur(iguadont type), beak-like mouth dinosaur, andjaw bones were found in Chaiyaphum Province.
This new recovery of a beak-like mouth dinosaur
was named Psittacosaurus sattayaraki (Buffetautand Suteethorn, 1992). This dinosaur was named
to honor Mr. Nares Sattayarak. The dinosaur was 1
m long seratopsian sauropod.
Dinosaur fossils, sealed in rock for million
years, require immediate preservation after being
exposed to the air. They are covered by plastercement for convenience in transportation fromthe excavation site to the laboratory. Soil and rockis then removed from the fossils by fine and sophisticated equipment. The bones are describedin detail, classified and interpreted before theresults are published in newspapers and paleontology journals. Finally, the bones are catalogued
and systematically arranged in a museum or othersecure university institution for future reference.
The results of the study and research aredisplayed as presentations of a simple and understandable story. Fragments of bone are reconstructed to make complete skeletons as isdemonstrated in museums around the world. The
important dinosaur museums in Thailand wereconstructed in the northeast. The first museum is
Research center and dinosaur museum, locatednear Phuwiang National Park, Khon Kaen Province
and the second museum is Sirindhorn museum,located at Wat Sakkawan, Sahatsakhan district,
Kalasin Province.

Siamodon nimngami : Found in Thailand, Siamodon nimngami is a new genus and new species of orinthopod dinosaur of
the world from the Middle Cretaceous period around 100 million years ago. Maxillas of the species have been excavated in
Khok Kruat Formation in a sandstone mine in Ban Sapan Hin,
Nakhon Ratchasima Province. The genus name Siamodon wasderived from Siam, the previous name of Thailand, and a Greek
word Odoust, meaning tooth, spelled as Odon to be similar tolguanodon. The species name nimngami was given after Wittaya Nimngam who gave the fossil sample for the study.

Rachasimasaurus suranareae: An lguanodon dinosaur, Rachasimasaurus suranareae, was found in Nakhon Ratchasima
Province. A loft lower jaw with no teeth from the Middle Cretaceous period around 100 million years ago was unearthedin the Khok Kruat Formation in Ban Pong Malaengwan, Muang
District, Nakhon Ratchasima Province.

23 Pre-Symposium Geology Excursion Guidebook

24 IGCP 608

EXCURSION
STOPS

25 Pre-Symposium Geology Excursion Guidebook

01

Dinosaur excavation site no. 3

Phu Wiang National park,Ban Khok Nong Kham,
Wiang Kao district, Khon Kaen Province

1First discovery of dinosaur in Thailand

The first discovery of dinosaur fossil in Thailand was made in 1976 when the
Department of Mineral Resources, Thailand sent out a geological team to conduct auranium exploration around Phu Pratu Teema foothill in the western side of the Phu
Wiang valley, Phu Wiang district, Khon Kaen Province. The team by Sudham Yeamniyam need to go for a pee, as usual, he walks away from the survey line about 15
meters and start pouring warm urine water onto the ground and uncovered the dirty
surface of a rubbish rock. Un-intentionally, as a geologist, with a glance ontothat piece of rock about one foot wide,
which shows diagnostic strange feature,look like a bone with dots and stripes
similar to the stripes on the ivory. They
took the bone back to them field campand later on delivered to the Department of Mineral Resources, Bangkok office for further identification. Thereafter,
it has been identified as a bone of “ Sauropod dinosaur” by Dr. Phillippe Taquet,the specialist of dinosaur from Institutede Paleontologie Museum National d’26 IGCP 608

Histoire Naturelle, Paris, Frannce. This bone fragment is regarded as the first known evidence of dinosaur in Thailand
and gave rise to the establishment a Thai - French paleontological expeditions project.
Since 1976 the Department of Mineral Resources
has been continuously exploring and researching dinosaur
fossils in Phu Wiang valley. The most prominent fossilised
dinosaur discovery at Phu Wiang valley is the first discovery of a new species including a Sauropod dinosaur later
named Phuwiangosaurus sirindhornae, as great interest on
dinosaur of Her Royal Highness Princess Maha Chakri Sirindhorn, the dinosaur researchers including Thai and Frenchpaleontologists have named a sauropod dinosaur found in
the Phu Wiang. Ancestor of tyrannosaur was also discovered
here, Siamotyrannus isanensis together with a spinosaurid,
Siamosaurus suteethorni and a small theropod dinosaur
Kinnareemimus Khonkaenensis, 1-2 meters in length, looking similar a modern ostrich.
Phu Wiang is therefore, an important place where
the first dinosaur evidence of Thialand was discovered withdiversified species.
Thai princess visited a dinosaur site; on 3rd November 1989, Her Royal Highness Princess Maha Chakri Sirindhorn visited the second dinosaur excavation site in the Phu
Wiang Mountain. After the year 1992 onwards, the Tourism
Authority of Thailand had allocated budgets for developing the dinosaur sites and later on the Phu Wiang Dinosaur
Museum for tourism. The museum has to public since 2001
administrated by the Department of Mineral Resources sofar.

27 Pre-Symposium Geology Excursion Guidebook

2

Phu Wiang Fossil Research Center and Dinosaur Museum
Phu Wiang National park, Ban Khok Nong Kham,
Wiang Kao district, Khon Kaen Province

2

Phu Wiang Fossil Researcs Center and Dinosaur Museum is the first and most important dinosaur museum in Thailand. The first exhibition was open to public in 2001. It is located at the Phu Wiang Mountains
where large specimens of dinosaur fossils were discovered. The museum facility is spacious and modern. The
facility contains versatile and fun activities including interesting research of the world and universe, the originof life, fauna, and flora evolution in the Jurassic Age.
The Museum is small museum of about 5,500 s.q. km and was constructed in 1999-2000. The museum
has been open to the public daily since 2001. The exhibition area has 15 sections. Exhibit subjects are theuniverse, planet earth, earth structure, earth surface, origin and rock cycle, origin and evolution of life, samples of rocks, minerals and fossil fuels, background of the Phu Wiang dinosaur site, Thailand dinosaur, contemporaneous creatures with dinosaurs, the dinosaur park, human evolution, uses of mineral resources, Phu
Wiang topography and local people’s lore.
The museum also has a conference room, library, paleontological laboratory, collection house, office,information booth, souvenir shop, and canteen. The DMR plans to build a youth camp at the museum forchildren from remote areas who cannot visit the museum and return home in one day. There is a master plan
to develop the museum into a dino-park in the future.

28 IGCP 608

Within the Museum

Standing prominently in the middle of the spacious exhibition hallis the sauropod replication statues of the Phuwiangosaurus sirindhornae made of metal with the body length of 12 meters and the Siamotyrannus Isanensis with length 7 meters. Also in the exhibition hall,
there are fossil replicas and collections which were found in Thailand
are exhibited behind glass with the history and photos of the Phu
Wiang dinosaur exhibition sites. These sites include Phu Kum Khaosite or Wat Sak Kawan at Sahatsakhan District, Kalasin Province, where
body skeletons of Phuwiangosaurus sirindhornae sauropod were discovered. These discoveries are claimed to be the most perfect andcomplete dinosaur skeletal structure ever discovered Thailand to date.
Also the paleontologist simulation laboratory and investigation sectionof the museum exhibit methods of scientific work and observation tovisitors who are interested.

Dinosaur Garden       Next to the main exhibition hall, visitors will find the Dinosaur Garden. ln the Dinosaur Garden, actual sized dinosaur replication statues ofpre-historic dinosaur fossils that were discovered in Thailand, including
the Phuwiangosaurus sirindhornae, Siamotyrannus isanensis, Siamosaurus suteethorni, Kinnareemimus khonkaenensis, Psittacosaurus sattayaraki and Compsognathus, are all created back into life with the simulation of the Jurassic Age environment. Deep rainforest, creek, waterfall,early plant species in Proterozoic era such as Ginkgo biloba, horsetails,
mosses and flourishing in this prehistoric garden environment. Once visitors walk cross the wooden bridge, these dinosaur statues are waiting togreet each visitor with their roars from both sides of the bridge mimicking
the feelings of the ancient Jurassic Age.

29 Pre-Symposium Geology Excursion Guidebook

3

Chao Pu Lup Shrine

Ban Phu Phan Thong, Muang Nong Bua Lamphu District,
Nong Bua Lamphu Province

3This stop intended to show the contact between two formations of the redbed Early Cetaceous the
Phra Wihan and the Sao Khua Formations of the Khorat Group. The Phra Wihan Formation is characterized bylight-gray, fine– to coarse-grained quartzitic and conglomeratic sandstone with rare gray siltstone and mudstone.
The formation was interpreted to have been deposited by braided river system (Meesook, 2000). The Phra
Wihan Formation is overlain conformably by the Sao Khua Formation. The Sao Khua Formation consists
mainly of incompetent bed (60-70%) grayish-red to reddish-brown, usually is slightly mottle. It is soft andeasily weathered in most places. Calcrete nodule can be seen in the reddish-brown siltstone and mudstone.
Sandstone beds are also contained in the Sao Khua Formation. It is about 30-40 % which is yellowish-gray toyellowish-brown and pale red sandstone in thick unit. It is characterized by fine- to medium-grained, well   30 IGCP 608

cement to friable, slightly to moderately calcareous
in some beds. At this stop the Sao Khua Formation
starts with thick-bedded of reddish-brown siltstone
and mudstone with abundant calcareous nodules.
The reddish-brown siltstone and mudstone is overlain
by thick-bedded of pale red sandstone. The formation
was interpreted to have been deposited by meandering river system (Meesook, 2000). As state by Meesook(2000) the repetitive change from braided (Phra Wihan)
to meandering (Sao Khua) river systems is corresponding to paleoclimatological change from slightly humid
to semi-arid condition.

Lithotratigraphic column of the stop 3

31 Pre-Symposium Geology Excursion Guidebook

4

150 Million Years Shell Museum

Ban Huai Dua Nuea, Muang Nong Bua Lamphu District,
Nong Bua Lamphu Province

4

Ancient shell fossils were firstly discovered in 1994 by local residents who searched for forest products
around an abandoned mine. They found a large number of beautiful shell-like stones including 150-million-yearold clam fossils and those of the ancestors of T.Rex Dinosaur in Nong Bua Lam Phu . Later, this area was developed into the site museum and regarded as the “UNSEEN” tourist destination. There are six zones as follows:32 IGCP 608

Zone 1: Reception Zone features the Dinosaur Family in Non Than Subdistrict, Nong Bua Lam Phu .
Zone 2: Exploring the Universe displays mobile models of the solar system including the Sun, Mercury, Venus,
Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto.
Zone 3: Earth: Generation of Living Things offers
knowledge in terms of evaluation of living beings on earth
including humans, plants, and animals from the past to thepresent.
Zone 4: Hunter Territory presents knowledge related
to dinosaurs and fossils discovered in Thailand. It also exhibits the dinosaur fossils found in Ban Huai Duea Village, Non
Than Subdistrict, Mueang District, Nong Bua Lam Phu andmodels of Siamotyrannus isanensis Dinosaur with the heightof 4 m. and length of 7 m. and eight-position motion.
Zone 5: Amazing Discovery exhibits wall models and150-million-year-old shell fossils with local language narration.
Zone 6: Walking with Surveyors features the working process of biologists and geologists including tools, equipment,
fossil studying steps, biology, and history of geological survey
in the source area of 150-million-year-old shell fossils.

33 Pre-Symposium Geology Excursion Guidebook

5

Wat Jetiyakhiri (Wat Phu Thok)
Phu Tok Noi, Si Wilai District,
Bueng Kan Province

5Type section of Thailand well bedded, thick-bedded sandstoneinterbedded with thick bedded mudstone. Cross-bedding, ripple
mark, dessicational crack are clearly observed. The folk constructionof the “sky bridge” is also miracle. The questions about the directionof paleo-current are very interested.

General: The outcrop type section of the Phu Thok Formation

is in the small isolated hill at Phu Sink –Phu Thok range. The 139 m
thick of sequence was performed in the western part of Khao Phu Thok
Noi but a complete section of two section is 205 m. Lithology of thisformation is characterized by alternation of two major sandstone types.
The first type is thick-bedded (up to 2-3 m), whitish purplish brownish
red to purplish brownish red, indurated, calcareous, very fine-grainedsandstone to siltstone, which usually have wavy structure and someripple structures. The other is reddish brown to brownish red, morefriable to rather indurated, fine- to medium- grained arkosic sandstone(up to 20 m thick), with large-scale, multi-directional, cross-bedding.
Fossils are not observed in the sequence.
Structure: Major structural trend in the adjacent area lies approximately in the NW - SE direction. This trend is a part of the regional
trend of the Khorat rock sequences in the northeastern Thailand. Fault

34 IGCP 608

system is the NW-SE fault, extending from Phu Kadan to Ta Khek
Fault in Laos. The trend of the fault is normally conformable withorientation of the mountain ranges. There are also minor faultsand fractures in the area trending approximately NW-SE and NE-SW
directions.
Folding of this terrane is the syncline which oriented approximately in the NW-SE direction in the lower part of the Phu Thok
Formation and slightly N-S direction in the upper part. The syncline
is about 20 km in length and 1-2 km in width. Dipping of the westernside of the syncline is about 50 to 100 NE and that of the easternpart is about 30 to 70 SW.
Stratigraphy: It is approximately more than 98% exposure
accounts for this rock sequence. Total column of the Phu Thok sandstone sequence can be separated by the combination of lithologies
and sedimentary features into three from four members as A, B, C,
and D (see geologic background).
Petrography: All of sandstone samples are lithic arkose toarkose ( Folk, 1968). Clasts are variably from subangular to wellrounded, with high sphericity, and normally medium-coarse sandsize (0.4-0.8 mm in diameter) of quartz, chert, and feldspars, withsome micas and rare volcanic rock fragments. The very fine-grainedsandstones are examined petrographically to be lithic arkose (Folk,
1968). It is noted that drusy calcite spar and poikilotopic in calcareous cement are recognized.
Environment: Fluvio-eolian? Deposit in semi-arid conditions
Age: Cretaceous-early Tertiary; the magnetostratigraphy needto re-interpretation

35 Pre-Symposium Geology Excursion Guidebook

6

Dinosaur Footprints

Ban Lao Had, Tha Uthen District,
Nakhon Phanom Province

6

Le Loeuff, J. et al. (2009) study the dinisuar footprint at Huai Dam Chum locality that is situated in theProvince of Nakhon Phanom, on the road between Nakhon Phanom and Bang Pang, NW of the confluence of the
Mae Nam Songkhram and Mekong rivers, about 18 km from the small town of Than Uthen. It was discovered by
N. Sattayarak from the Department of Mineral Resources in a sandstone quarry where large blocks are extracted
to consolidate the banks of the Mekong river. In February 2003, we were able to observe several large displacedslabs in the quarry showing small theropod footprints, but we could not locate the track layers in situ (Le Loeuff
et al. 2003). A few months later, an in situ slab was located, and it was cleaned in February 2004. It revealed an
impressive assemblage of more than 200 footprints of small theropods, ornithopods and crocodiles.

36 IGCP 608

Most of the footprints are theropod footprints, whichwere suggested by Matsukawa et al. (2006) to be similar to
Asianopodus from China and Japan. Although the footprints
show some similarities they are also consistently smaller
than Asianopodus. It seems that the parallel theropod trackways were not left by a single group but by several small
packs of theropods, as evidenced by the varying calculated
speeds.
Two successive footprints are didactyl and could represent either deinonychosaur footprints or some unknown
small theropod (Le Loeuff et al. 2003); however, we cannot
rule out the possibility that these two footprints are poorly
preserved tridactyl footprints (see Milan 2006; Milan&Bromley2006).
A single ornithopod trackway of four footprints has been
discovered on the main slab; the footprints show three large
rounded digits, very similar to footprints from Japan describedby Matsukawa et al. (2006). These footprints were left by advanced ornithopods with fleshy digits and a digitigrade stancevery distinct from the older Neoanomoepus tracks from the
Phra Wihan Formation. The Japanese footprints were referredto the ichnogenus Caririchnium, to which we provisionally refer
the footprints from Tha Uthen.
This remarkable site was acquired in 2007 by the Department of Mineral Resources. Further excavations and the building of a roof were realized in 2008.

37 Pre-Symposium Geology Excursion Guidebook

7

Wat Phra That Phanom

Ban Hua Wiang, Muang Nakhon Phanom Distrct,
Nakhon Phanom Province

7

Phra That Phanom is a tall spire - a style of pagoda (chedi) common to Northeastern Thailand and Laos.
The tower sits inside a large temple formally called Wat Phra That Phanom Woramahawiharn. The tower isthought to have been constructed some time in the eighth to tenth centuries, but like many temples it has beenrenovated many times since it was first built. The last major reconstruction happened after the spire was blown
over by high winds in 1975.
The tower is perhaps the most important of several thats spread around the northeast of Thailand. Phra
That Phanom sits in the smallest of three concentric courtyards. The outermost courtyard is enclosed by a highwall that forms the outer wall of the sacred precinct, and encloses not only the tower, but the temple’s main
prayer hall and a large platform directly to the east f the tower where most people come to make offerings. The
inside of the outer wall is covered and lined with Buddha images in a variety of poses.
The middle wall just encloses the tower, with a large area on
the east side where people come to pray and make offerings. The inside of this middle wall contains several rather contemporary morality
scenes with admonitions against drugs, etc. The innermost wall is justbig enough to surround the base of the tower, and the doors in its fourgates are rarely open. The spire has a large teak door on its easternside, but I haven’t found any information about what is inside.
West of the main enclosure are a few other buildings and structures of interest. Near the northwest corner of the outer wall is a large
elaborate bell tower. Whether it is new, or simply newly renovatedwhen I visited, I’m not sure. A little further to the west, descend-

38 IGCP 608

ing from the platform that supports the religious
structures, there’s a small museum. I can’t say
it’s very interesting, although just outside of theentrance a large section of the old collapsed
tower is on display. Thought to date from theseventeenth century, when a monk from Vientiane came to rebuild the that, the cap-piece iscast from a number of different metals.
East of the main temple area is a large squatbuilding that sits in a large pond. The structure islabeled Stupit That Phanom in large Thai letters,
but there’s no other information about what it is.
There are two bridges across the pond to it, but
the gates on both were closed and locked.
The temple is the center of an annual festival which starts on the 10th day of the third lunar
month and runs for a week. The estimated date
for the next festival is 1 March 2019. Note that
hotels and guest-houses in the entire Province
are full up during this time, so if you expect tovisit during the festival you’ll need to book early.

(http://thailandforvisitors.com/isan/nakhon-phanom/
that-phanom/wat-phra-that-phanom.php)

39 Pre-Symposium Geology Excursion Guidebook

8

Huai Huat Reservoir

Phuphayol National Park, Tao Ngoi District,
Sakon Nakhon Province

8This stop presents the exposure of the Early
Cretaceous Phu Phan Formation. The formation
lies between the non-resistant the Sao Khua andKhok Kruat Formations. The rocks are composed
mainly of yellowish-gray to pale orange, pinkishgray and pale red, thick-bedded sandstone, conglomeratic sandstone with large cross-bedding.
The clasts of conglomerate consist of quartz,
chert, sandstone and some volcanic fragment.
As state by Meesook (2000) the Phu Phan Formation was interpreted to have been depositedby braided river system which is relatively higher
energy than in the Phra Wihan Formation. Furthermore, the very thick-bedded unit of conglomeratic
sandstone and conglomerate at the top of the
Phu Phan Formation are the most widespread ofany formation in the Khorat Group. Palaeocurrent
direction measured from cross-bedding indicatedthat the palaeocurrents was running toward thewest and southwest.

40 IGCP 608

41 Pre-Symposium Geology Excursion Guidebook

9

Sirindhorn Museum

Phu Kum Khao, Sahatsakhan District,
Kalasin Province9

1. History of Dinosaur discovery
Dinosaur fossilized remains at Phu Kum Khao was first discovered in 1970 by a senior
Buddhist monk named Visamtaera (Reverend Vichit Sahaskun), the abbot of Wat Sakkawan. The
abbot unknowingly kept them, mistakened them for pieces of petrified wood. In the year 1983
Dr. Varavudh Sutheethorn, a geologist and a member of the survey team from the Departmentof Mineral Resources, was conducting a survey in the nearby
area. Dr. Varavuth saw the fossilized bones, and recognizedthem for what they were. In 1986 a French-Thai Palaeontological team took three pieces of tile bones for identification.
It was later discovered that the three pieces turned out to be
the front leg bone of a sauropod. In October of 1987 a fossil
deposit was discovered by a roadside ditch at the foothill.
The initial, systematic excavation and preservation began at
this site.
However, the point of discovery was at a height ofrainy season, and further excavation was made impossibleby rain water. The excavation was postponed until November of the same year. Subsequent opening of soil surface
unearthed more bones, and still much more yet to be dis-

42 IGCP 608

covered. In October of 1988 the number of dinosaurs discovered
reached six individuals - more than 630 pieces of bones. The
team built a shelter over the site to protect it from sunlight andrain, and afforded additional digging. Reverend Vichit Sahaskun
gave the team the use of one of the temple’s pavilions as a temporary shelter, and operational center which allowed the team
to excavate further.
On November 24, 1988 Princess Maha Chakri Sirindhorn
visited the site of the excavation and afforded additional digging.
At Phu Kum Khao many fossilized remains of dinosaurs were discovered in sandstone of Sao Khua Formation of Early Cretaceous,or about 130 million years ago. The most numerous fossilized
remains ever discovered in Thailand more than 650 pieces, or atleast seven individual sauropods were found at this site. Almost
all the pieces of skeletal structure were found, and one individual skeleton was found almost intact. Furthermore, many piecesof teeth and skull fragments were also discovered.
These later discovery revealed that there were four species of dinosaurs in this area. Two were sauropods, one identified
as Phuwiangosaurus sirindhonae, and the other is still waiting forthe final identification. The latter two were identified from theirfossilized teeth as two large teropods of separate species: Siamosaurus suteethoni, and Siamotyrannus isanensis. Other creaturesof their contemporary discovered were, e.g., gastropods (freshwater bivalves), lepidotes fish, Goniopholis crocodiles, primitive
turtles, and freshwater hybodont sharks.

43 Pre-Symposium Geology Excursion Guidebook

2. Sirindhorn Museum

The Sirindhorn Museum (Phu Kum Khao Dinosaur Museum) is located at the Phu Kum Khao , Sahatsakhan District, Kalasin Province and about 30 kilometers to the north of Kalasin Province. It can be accessedby highway no. 227. The area is generally high mountainous and undulating landforms.
The Sirindhorn Museum is the museum of the Department of Mineral Resources for storing, research,and displaying the fossils, especially dinosaur fossils. It also acts as a learning center and tourism attraction
for the general public. This Museum is an important tourism attraction site and contains new dinosaur generaand species first found in Thailand.  The museum has academic value and beauty that attracts a large numberof both Thai and foreign tourists. Thus far, there have been more than 300,000 visitors, and each passing year
adds significantly to this total. The museum has a conservative approach totourism activities and has good cooperation from local communities, helping local people to supplement their income
by producing and selling souvenirs. The
museum is opened daily between 8.30
am -17.00 pm.
The Sirindhorn Museum
has three main parts: the excavation site
museum, the fossil storage and researchbuilding, and the permanent museum

44 IGCP 608

building. The museum has a 500-seat conference room, two executive meeting rooms, and a 120-seat theater,
together with a temporary exhibition room, library, souvenir shop, and canteen. Outside of the museum there
are spaces for a dinopark, parking lot, and youth camps.
The Sirindhorn Museum has an important role in research of dinosaur, mammal vertebrates, invertebrates, plants, and trace fossils. The museum has a modern standard collection room and a fossil preparationlaboratory for use by its research staff. The fossil specimens in the museum range in size from microscopic pollen grains to very large pieces of dinosaur bones. These specimens are scientifically and systematically caredfor, with all data recorded in an electronic database. The research results are published in scientific journals
and books.

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Excursion Route Map
20187