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Chapter 80. Biostratigraphy of Paleogene non-marine Ostracoda from East China

Chapter 80. Biostratigraphy of Paleogene non-marine Ostracoda from East China

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D.s. VANNIEUWENHUISE AND F. M.SWAIN

1154 J. D.HE,



ASSEMBLAGE I



0



ASSEMBLAGE I I



0



0

ASSEMBLAGE IVl B

ASSEMBLAGE 111



ASSEMBLAGE lV2 0

ASSEMBLAGE V1

ASSEMBLAGE V2



TEXT-FIG. 1-Localities



A

A



in East China from which ostracode assemblages were obtained.



111. Echinocypris fabaeformis-Cyprinotus

Middle Eocene.



(Heterocypris) jianglingensis assemblage of the



.



IV, Non-marine type : Cyprinotus (Heterocypris) macronefandus-Cyprinotus (Heterocypris)

igneus assemblage of the Late Eocene.

IV2. Marginal marine type: Cyprinotus (Heterocypris) yongningensis-Austrocypris levisChinocythere subcornuta assemblage of the Late Eocene.



V,. Non-marine type : Cyprinotus (Cyprinotus)hubeieniss-Cyprinotus (Heterocypris)jinheensisPinnocypris postiacuta assemblage of the Oligocene.

V,. Marginal marine type : Hebein ia-Huabeinia-Dongyinia- Candona-ParachinocytheveChinocythere assemblage of the Oligocene.

Assemblage I was first found in the Shanghu Formation of the Nanxiong Basin in 1964 (Guan,

1978). During the Paleocene, the most abundant and widespread Mesozoic forms, such as Cypridea and Talicypridea species, dwindled and vanished. They were replaced with similar Cenozoic

genera, Cypridea (Cypridea) xindianensis HOU,1978, C . (Guangdongia) speciosa Guan, 1978, c.

(Pseudocypridina) subtera Hou, 1978, Parailyocypris taizhouensis Yang, 1982, Ilyocypris sub-



Paleogene Non-marine Ostracodafrom East China 1155



EARLY TERTIARY OSTRACODES OF EAST CHINA



TEXT-FIG.

;?-Stratigraphic ranges of Early Tertiary ostracodes of East China.

huanggianoensis Hou and Yang, 1982, Porpocypris subglobra (Zhou), 1982, and Cyprois depressa

Chen, 1982 (Guan, 1978; He, 1979).

The greatest resemblance among the Paleocene ostracode species is found in those from the

Chejiang Formation in Hengyang Basin of Hunan, the Lower Member of Fangjiahe Formation in

the marginal region of the Yang tze-Han River Plain of Central Hubei and in the First Formation

of the Funning Group in Northern Jiangsu (Text-fig. 3). They are characterized by the presence

of rare Cypridea and by several Cenozoic genera. The assemblage can be correlated with similar

ostracodes in Fort Union Formation in the Western Interior of the United States (Swain et al.,

1971). Assemblages from both regions contain bisulcate Cypridea, such as Cypridea (Guangdongia)

speciosa Guan, 1978, which is closely similar to Cypridea nyensis Swain, 1964.

Assemblage I1 has a widespread distribution and a preponderance of typical Cenozoic genera



1156



J. D.HE, D. S. VANNIEUWENHUISE

AND F. M. SWAIN

v ) d

Guangdong

Guangxi

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Hubei

2 E

b 8 'Nanxiong Sanshui Leiqiong Nanning Hengyang Dongting c

;

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;

;

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Basin

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2



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Member

m



111 Danxia Frn



--



Shiziling



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.-



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Frn

Frn

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----



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Deshan



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r



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Upper

Mbr u Mbr

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.-m



0



.p

Lower .g Lower

a

X

Mbr



Mbr



TJXT-FIG.3-Correlation of the Early Tertiary strata bearing non-marine ostracods in East China.



and species, The assemblage consists mainly of Cypris decaryi Gauthier, 1933, C.favosa Ye, 1978,

Eucypris stagnalis Mandelstam, 1963, Eucypris subtriangular Ye, 1978, Sinocypris funingensis Ho,

1982, S. Parailyocypris changzhouensis Yang and Hou, 1982, Limnocythere hubeiensis Ye, 1978,

and L. spinisulata Ye, 1978 (Hou et al., 1978, 1982).

Sinocypris is the most abundant ostracode throughout the entire Lower Eocene, but especially

in the lower part of the Lower Eocene. A non-marine ostracode assemblage very similar to this

assemblage is known from the Colton and Wasatch formations in the Western Interior of the

United States (Swain, 1964) and the White Bed of Nemegt Basin in Mongolia (Szczechura, 1971).

An important form, such as Sinocypris funingensis Ho, 1982, is very similar to Hemicyprinotus

watsonensis Swain in its weakly reticulate surface. Other species of the assemblage, such as Cypris

favosa Ye, 1978, are very similar to Pseudoeucypris pagei (Swain, 1956) of the Colton Formation

in the Western Interior of the United States. Hemicyprinotus watsonensis and Pseudoeucypris

pagei are zonally significant in the Colton Formation in Colorado, Utah, and Wyoming. In the

Western Interior of the United States, Cypridea-like species are rarely found in the Eocene and

Paleocene.

Some of the Cenozoic non-marine ostracodes probably evolved from Cypridea (Text-fig. 4).

In morphology, especially the compressed mid-dorsal area and inner microstructure, Sinocypris

is related to Quadracypris. Among the other significant forms of Sinocypris is S. reticulata Zhang

and Guan, 1978. Sinocypris reticulata may have evolved from S.funingensis; it is subtriangular in

outline, highest anteromedially; the left valve is slightly larger than the right, overlapping along

free margins, especially the anterodorsal margin. These morphological features are quite similar

to other types of Late Paleogene and Neogene ostracodes. It is suggesteed that Sinocypris reticulata

is more advanced than Sinocypris funingensis and it has a greater geographic distribution. Follo-



Paleogene Non-marine Ostracoda from East China 1157



Henan



Zhejiang



Bohai



Shanxi



Xuanguang Hangjiahu

Basin

Plain



Region



Yuangu

Basin



Anhai



Nanyang Jiangsu

Basin



United States

Western Interior



sw Montana

Basins

E DunbarCreek



u.



Liaozhuang



Mbr



Baishuicun m =Basin ?

E



'LL



Upper



Fm



Mbr



Mbr



Upper 4th

Mbr

:'u Middle 4th

5

Mbr



Hetaoyuan 5

c

g

Fm



5 Mbr



a/wMb?,



CO-Utah-WY

Basins



Florissant Fm

White River

Fm

Duchesne Fm



Hedi Fm



LL



Uinta Fm



Green River



Yuhangding Dainan Fr



Wasatch



Fm

I



I



I



wing the evolutionary development of Sinocypris, the ostracode assemblage of the Early Eocene

can also be separated into two subassemblages. The lower Early Eocene subassemblage includes

Sinocypris funingensis Ho, 1982, S. multipuncta Ho, 1982, and is associated with many other Cenozoic species. This subassemblage occurs in the Second, Third and Fourth Formations of the



e



I

1

I



I



Sinocypris funingensis



I



I

I



I

I

I



Quadracypris



Talicypridea



\



Cypridea



TEXT-FIG.

&Possible evolutionary relationships of several taxa.



1158 J. D. HE,

D.S.



VANNIEUWENHUISE

AND F. M.SWAIN



Funning Group of Jiangsu, the Buxin Formation of Sanshui Basin, the Luofuzhai Formation of

Nanxion Basin and the Lower Member of the Liushagang Formation of Leiqiong subregion, the

Xialiushi Formation of Hengyang Basin, the Second Formation of the Zhanghe Group of Zhejiang

and the Middle Member of the Shuangta Group of Xuanguang Basin. The subassemblage of

ostracodes from the upper part of the Early Eocene consists mainly of Sinocypris reticulata Zhang

and Guan, 1978. This species is widely distributed in the Dainan Formation of Jiangsu, the

Limuping Formation of Hengyang Basin, the Huayong Formation of Sanshui Basin, the Upper

Member of the Fangjiahe Formation of Hubei and the Upper Member of the Shuangta Group of

Xuanguang Basin.

Worthy of notice is that the Early Eocene Continental Basin in East China can separated into

two biogeographic regions: the northern and the southern, with the area from Lianyunguang to

Quinling Moutains as the borderland. The two regions can easily be distinguished from each other

by the presence of Sinocypris in the southern region and its absence in the northern region.

Assemblage I11 is the Middle Eocene assemblage. Following the extinction of Sinocypris at the

end of the Early Eocene, Echinocypris and Cyprinotus became the dominant non-marine ostracodes,

possessing strongly endemic characteristics. This assemblage consists of Echinocypris elongata

Jiang and Li, 1978, E. fabaeformis Li, 1978, Cyprinotus (Heterocypris)jianglingensis He and Zhang,

1982, C. (H.) formalis Schneider, 1963, and a few specimens of Candona, Zlyocypris, Eucypris

and Limnocythere (He et al., 1982). Assemblage I11 has been found at several localities such as

in the Jingsha Formation of the Jianghan Plain, the Deshan Formation of Dongting Basin, the

Daicangfang Formation of Nanyang Basin and the Lower Member of the Sanduo Formation of

Jiangsu. However, Echinocypris is mostly limited to Hubei, Hunan and Henan Provinces. The

echinulate forms have not been seen in the First Member of Sanduo Formation. Both are characterized by the presence of numerous species and individuals of Cyprinotus, especially in the

Jiangsu Province. The faunas can be correlated with each other on the basis of Cyprinotus spp.

Middle Eocene Land Mammals were found in the Daicangfang Formation of Henan. These

include Coryphodon sp., Palaeosyops sp., cf. Breviodon sp. and Euryodon minimus Xu et al., 1979

(Li and Ting, 1983).

Besides the above-mentioned series of ostracode bearing rocks in East China, there are nonfossiliferous rock sequences which consist of reddish-brown sandstones and conglomerates, such as

the Danxia Formation of Nanxiong Basin, the Shiziling Formation of the Western Jianghan Plain,

and the First Member of the Kongdian Formation to the lower part of the Fourth Member of the

Shahejie Formation of the Coastal Region of Bohai. Present interpretations are that these strata

overlie the Cypris-Sinocypris-Eucypris-Parailyocypris-Limnocythere assemblage of Early Eocene.

The nonfossiliferous strata series seem to be Middle Eocene.

Assemblage IVI. (Non-marine type) In this assemblage, the Cyprinotus (Heterocypris) spp. are

very diverse in species with abundant populations, represented chiefly by Cyprinotus (Heterocypris)

macronefandus Li, 1978, and C. (H.) igneus Hou et al., 1978. The assemblage occurs in the Qianjiang Formation of the Jianghan Plain, in the Hetaoyuan Formation of Nanyang Basin, in the

middle part of the Fourth Member of the Shahejie Formation of the Coastal Region of Bohai

and in the Hedi Formation of Yuanqu Basin. However, the genera and species of assembage IV

are different in the East China Region. For example, the assemblage of the Jianghan Plain consists

of Cypris decaryi Gauthier, 1933, C . (H.) gonganensis He and Zhang, 1982, Pseudostenocypria?

triangularis He and Zhang, 1982, Paracandona euplectella (Brady and Norman, 1889), Zlyocypris

biplicata Sars, 1838, Z. cornae Mandelstam, 1961 and Virgatocypris ovata He and Zhang, 1982.

(He et al., 1982). In the Coastal Region of Bohai, ostracodes are less abundant. There, Cyprinotus

(Heterocypris) igneus Hou et al., 1978, is associated with a few species of Cypris, Eucypris and

Cyprois (Hou et al., 1978).



Paleogene Non-marine Ostracodafrom East China 1159



In addition, a rich Late Eocene land mammal assemblage co-occurring with ostracode assemblage IVl was recently discovered in the Hetaoyuan Formation of Henan and in the Hedi Formation of Yuangu Basin (Li and Ting, 1982). Characteristic fossils are Zctopidium lechei Zdansky,

1930, Hoanghonius stehlini Zdansky, 1930, Cricetodon schaubi Zdansky, 1930, Hyaenodon yuanchuenesi Young, 1937, Chailicyon crassidens Chow, 1975, Rhinotitan mongoliensis (Osborn, 1925),

?Amynodon mongoliensis (Osborn, 1930), Sianodon sinensis (Zdansky, 1930), Anthracokeryx sinensis

(Zdansky, 1930).

Assemblage IV, has only been found in a few localities which are the upper part of the Fourth

Member of the Shahejie Formation in Coastal Region of Bohai, the Upper Member of the

Liushagang Formation of Leiquiong subregion and the Yongning Formation of Nanning Basin.

This assemblage is allied to, but distinct from, both non-marine freshwater ostracode assemblages

and sub-littoral marine ones. In other places, only a few taxa and individuals occur. The Yongning

Formation is represented by Xiyingia cuneata He, 1981, Cyprinotus (Heterocypris) yongningensisHe,

1981, Zlyocpris jinjiensis He, 1981, Chinocythere xixiangtangensis He, 1981 and C. subcornuta He,

1981 (He, 1981). Ostracodes from the upper part of the Fourth Member of the Shahejie Formation

are represented by Cypris postilonga Hou et al., 1978, Candona acclivis Hou et al., 1978, Austrocypris levis Hou et al., 1978, A. posticaudata Hou et al., 1978, Pterygocypris caudata Hou et al.,

1978, Miniocypris subaequalis Hou et al., 1978, Limnocythere longipilerformis Hou et al., 1978,

L. nodosa Hou et al., 1978, L. striatituberosa Hou, et al., 1978, Chinocythere Iongicymbiformis

Hou et al., 1978, C. ventricostata, Hou et al., 1978. (Hou et al., 1978). This fauna is abundant and

diverse. Ostracodes are rare in the Upper member of the Liushagang Formation, which includes

mainly species of Eucypris and Chinocythere (South Sea Branch of Petroleum Corporation of the

People’s Republic of China et al., 1981).

The characteristics of assemblage IV, are summarized as follows :

1) Assemblage IV, is characterized by species of a few common freshwater genera such as

Cypris, Cyprinotus, Candona, Zlyocypris and Limnocythere as well as new forms, such as Austrocypris, Xiyingia, Pterygocypris, Miniocypris, and Chinocythere. The new forms bear some of the

same carapace features as nearshore marine and brackish forms, for example, Chinocythere

resembles Leptocythere, which is a marine genus. Chinocythere is quite similar to saline non-marine

forms of Elkocythereis found in the upper and middle parts of the Humboldt Formation of northeastern Nevada in the United States. Austrocypris bears some resemblance to Cytherura, the latter

being a shallow-marine form. In addition, in the Coastal Region of Bohai and in the same horizons

with the above-mentioned ostracodes, there have also been reported foraminifera-Dejlandrea

and Cladosiphonia-but, curiously enough, no typical marine ostracodes have been discovered

(Hou et al., 1978). The marginal marine or saline lake assemblage seems to be related more to

saline than to fresh-water masses, suggesting that there may have been a sea invasion at that time,

or that the lakes evaporated significantly and became saline enough to support foraminifera.

2) Austrocypris, Chinocythere and Xiyingia are brackish-water genera that seem to have originated in the Coastal Bohai Basin, Nanning Basin and Leiquiong subregion and are not found

elsewhere in China.

3) Assemblage IVI (Non-marine) and assemblage IV, (marginal marine) have several similar

genera and species. For example, Cyprinotus (Heterocypris) sp. 1 from the Hedi Formation of

the Yuangqu Basin (unpublished manuscript). Thus the ostracode assemblage of the transitional

type can be correlated with the ostracode assemblage of the continental type and on the basis of

land mammal ages (LMA) they are regarded as Late Eocene.

Assemblage V1 (Non-marine type) is represented chiefly by Cyprinotus (Cyprinotus) hubeiensis

He, 1982, C. (Heterocypris) jingheensis (Li, 1978), C. (H.) jintanensis He, 1982, Pinnocypris

postiacuta Zhou, 1982, P.alata Zhou and Cyprois xiangxiangensis Guan, 1978, which are associated



1160 J. D. HE,D. S. VANNIEUWENHUISE

AND F. M. SWAIN



with a few species of Cypris, Eucypris, Pseudoeucypris, Ilyocypris and Limnocythere. The species

of Cyprinotus are numerous and widely distributed. The assemblage is believed by Chinese scientists

to be Oligocene on the basis of charophytes and ostracodes. The abundant species of this

assemblage are very similar to those of the Renova Formation of the Jefferson Basin in the United

States. The same or closely similar species of Cyprinotus (Heterocypris), Cyprois and Ilyocypris

are also found in the Renova Formation. The principal difference between the two regions is that

the species of the subgenus Cyprinotus (Cyprinotus) and the genus Pinnocypris do not occur in

the Renova Formation of the Jefferson Basin.

Assemblage V, (Transitional type) This assemblage is very rich in both species and individuals.

New forms, such as Huabeinia, Tuozhuangia, Hebeinia, Dongyingia, Camarocypris, Ninghainia,

Glenocypris, Xiyingia, Berocypris, Crepocypris, Megacypris, Guangbeinia,Fusocandona, Phacocypris,

Ammocypris, Chinocythere, Potamocyprella, Pterygocypris, Minocypris, Nexypria, Stipitalocythere,

Parachinocythere, Nanningcythere are most abundant, as well as a few common freshwater

species of Cypris, Eucypris, Virgatocypris, Herptocyprella, Cyprinotus, Candona, Paracandona,

Tuberocyproides. Cycloscypris, Cypria, Cyprois, Zlyocypris, Ilyocyprimorpha, Metacypris and

Limnocythere. This assemblage was first found in the First, Second and Third members

of the Shahejei Formation and in the Dongying Formation in Coastal Region of Bohai (Hou

et al., 1978). Later it was recorded from the Weizhou Formation of Leiquiong subregion and

the Yongning Formation of Nanning Basin. (South Sea Branch of Petroleum Corporation

of the People’s Republic of China et al., 1981; He, 1981). The generic components of the Third

Member of the Shahejie Formation up to and including Dongin Formation are numerous, but

the Weizhou Formation and Yongning Formation, although similar on the whole, have only

a few genera.

From the character of the ostracode assemblages, assemblagesV, and IV, are alike, but assemblage V, embraces many new forms which reach their peak of diversity in the assemblage. The

marine organism Leglunia, Pentagonus, fossil tubes of Serpulimorpha and foraminifera have also

been discovered in the Coastal Region of Bohai (Hou et al., 1978). Additionally, some results

from Early Tertiary shales of the Yongning Formation in Guangxi (He, 1981), indicate that the

“equivalent boron” is around 200 ppm (see Walker and Price, 1963), suggesting an oligohaline

marginal marine or saline lake environment.



ACKNOWLEDGEMENTS

Appreciation is expressed to the Department of Geology, the University of Delaware, which

provided facilities for study. The work at the University of Delaware was partly supported by a

grant from the National Science Foundation (EAR-8304028) to F. M. Swain. Appreciation is

also expressed to the Amoco Production Company, Tulsa Research Center for supporting field

work in southwestern Montana and’ to W. B. Hanson and Dr. R. W. Pierce of Amoco for

reviewing the southwestern Montana Tertiary successions.



REFERENCES

DICKINSON,

K.A. and SWAIN,

F.M. 1967. Late Cenozoic Freshwater Ostracoda and Cladocera from Northeastern

Nevada. J. Paleont.. 41, 335-350, 5 pls.



Paleogene Non-marine Ostracodafrom East China 1161

1978. On fossil ostracodes from the Nanxiong Basin and their stratigraphic significance. Paper of

Stratigraphy and Paleontology, 4, 151-1 59.

HE, J.D. 1931. Early Tertiary Ostracodes from the Naming Basin in Guangxi. Bull. Nanjing Inst. Geol. and Palaeont., Acad. Sinica, no. 3, 211-240, 7 pls.

-and JUAN, R.J. 1979. Late Cretaceous-Paleogene deposits of the Nanxiong Basin, Guangdong. Acta Stratigr.

Sinica, 3, (l),

30-39.

-and ZHANG. X.J.

-1982.

-~ Cretacious-Tertiarv Ostracodes from the Yanatze-Han River Basin in Hubei. Bull.

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and Cenozoic Red Beds of South China, 240-268, 6 pls. Science Press, Beijing.

HOU, Y.T. et al. 1978. Early Tertjary Ostracode fauna from the Coastal Region of Bohai. 205 pp., 83 PIS. Science

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-et al. 1978. The Cretaceous-Tertiary Ostracodes from the marginal region of the Yangtze-Han River Plain in

Central Hubei. Mem. Nanjing Instit. Geol. and Paleont. Acad. Sinica, 9, 130-206, 19 PIS.

-et al. 1979. Advance in study of Mesozoic and Cenozoic Ostracoda in China. In KRSTIC, N. (ed.). Taxonomy, Biostratigraphy and Distribution of Ostracodes, 103-108, Serbian Geological Society, Beograd.

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-et al. 1982. Subdivision and correlation of the Cenozoic strata in China. In Stratigraphic correlation chart in

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MOORE, R.C. 1958. Introduction to Historical Geology, 432-455, McGraw-Hill Book C., Inc., New York.

POMERAL, c . 1982. The Cenozoic Era, Tertiary and Quaternary. Ellis Horwood Ltd., Chichester.

ROBINSON, G.D. 1963. Geology of the Three Forks Quadrangle Montana. US. Geol. Survey. Prof. Paper, 3 7 0 , 6 8 0 .

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SZCZECHURA, J. 1971. Freshwater Ostracoda from the Paleocene of the Nemegt Basin, Gobi Desert, Mongolia.

Paleont. Polonica, no. 25, 85-96, 4 PIS.

WALKER, C.T. and PRICE, N.B. 1963. Departure curves from computing paleosalinity from boron in illites and shale.

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GUAN, S.Z.



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Cretaceous and Palaeogene Ostracod Biostratigraphy

in Xining and Minhe Basins of China

Y I - c m HAO

Beqing Graduate School of Wuhan College, P. R. China



ABSTRACT

The Xining and Minhe Basins bordering on each other around Ledu in northwestern China

cover a wide area from the west of Lanzhou in Gansu province to the east of Xining in Qinghai

province (Text-fig. 1). In these inland basins, Mesozoic-Cenozoic terrestrial deposits of great

thickness and rich in mineral resources such as coal, oil and salt, have been deposited. The

Cretaceous and Palaeogene strata, which range from about 1,400 to 3,400 meters in thickness,

contain abundant remains comprising microfossils such as non-marine ostracods, charophytes,

spores and pollen, as well as macrofossils including freshwater bivalves, gastropods, estherians,

freshwater fishes, reptiles and plants.

In the present paper, biostratigraphy of the Cretaceous and the Palaeogene is discussed in terms

of ostracod and charophyte assemblages.



CRETACEOUS AND PALAEOGENE



LITHOSTRATIGRAPHY

(TABLE

1)



The Cretaceous is divided in ascending order into the Datonghe Formation which includes part

of the Upper Jurassic, the Hekou Formation and the Minhe Formation (Ha0 et al., 1982, 1983).

The Datonghe Formaion is mainly represented by greyish-green and greyish-white, sandy conglomerate and sandstone with interbedded brown mudstones in its lower part; by brown and brownish-red mudstone and siltstone with intercalations of greyish-green and brown sandstone and

variegated shale in its middle part, and by brick-red sandstone and conglomerate with intercalations of thin-bedded brown silty mudstone in its upper part.

The Hekou Formation comprises reddish-brown sandstone and sandy conglomerate in its

lower part; reddish-brown and green mudstone with variegated shale containing interbedded sandstone in its middle part, and reddish-brown mudstone, reddish-brown, orange conglomeratic

sandstone and sandy conglomerate with intercalated reddish-brown mudstone in its upper part.

The Minhe Formation is lithologically subdivided into two parts. The lower part consists of

reddish-brown sandy conglomerate and the upper part of reddish-brown mudstone and siltstone

with interbedded greyish-green sandstone and gypsum.

The Palaeogene strata comprise in ascending order the Qijiachuan Formation, the Honggou

Formation and the Mahalagou Formation (Ha0 et al., 1983).

The Qijiachuan Formation consists of clastic deposits mainly represented by dark brown

mudstone, silty mudstone and greyish-brown greyish-green sandstone with gypsolite intercalations

and brown coloured basal conglomerate.

1163



TABLE

I-ETACEOUS



AND LOWER



TERTIARY

STRATIGRAPHY AND FOSSIL

ASSEMBLAGE SEQUENCES IN XINING

AND M~N HE

BASINS.

. .

Fossil Assemblages



StratiFormation/Epoch



I

Mahalagou



.-. .-.



-



Konggou Formation

E:-3

!ijiachuan Formation

Ei-E:



~



.



MinheFormation



KZ



E..

.- .-.

--._--.-- .

-.-.-.

--I ..

- . .-.

-. O .



0 . 0 .



0 . 0 .



*



0 .



0



.e



. 0 . 0 . 0 .



HekouFormation

K,



.....

.-. .-. .

- - -_

.-.-.



~-



0 . 0 . 0 . 0



. O



. O .



0 .



. .

-.-......



- - ..- .0 . 0 . 0 . 0



Datonghe Formation

J3+



Moedlerisphaera chinensis Huang and XuGrovesichara minheensis Yang Assemblage



Limnocythere hubeiensis Ye-L.

languida Song Assemblage



Gyrogona qianjiangica Z. Wang-Sphaerpchara minheensis Yang Assemblage



Talicypridea reticulata (Hou)-Cypridea

(Cypridea) cavernosa Galeeva-Cypridea

(Pseudocypridina) longa Hou-Eucypris

qinghaiensis Song Assemblage

Upper

Cypridea (Cypridea) sanmachiensis SongRhinocypris ventriconcava Hao-Ziziphocypris costata (Galeeva) Assemblage

Middle

Cypridea (Cypridea) unicostata GaleevaCypridea (Ulwellia) koskulensis Mandelstam Assemblage

Lower

Lycopterocypris infantilis-L. flaccida Song

Assemblage

Minheella minheensis Song and ChengJingguella hutouyaiensis Hao-Damonella

huangshuiensis Hao-Protolimnocythere pingua Cheng Assemblage



--- -



I

2



Conglomerate



Sandy conglomerate



languida



-



- .....

--0



llyocypris ellipsoidea-Eucypris milagouensis

Song-Cyprinotus

jucundus Song Assemblage



Cypris decaryi Gautheir-Limnocythere

hubeiensis Ye Assemblage



. 0 . 0 . 0 .



.e.



Charophyta



Ostracoda



I



Sandstone



Siltstone



Mudstone



Stephanochara breviovlis Lin and HuangNeochara squalida Z. Wang and Lin Assemhlage



Latochara curtula Z. Wang-Gyrogona hubeiensis Z. Wang-Charites guanpingensis

Z.Wang Assemblage



Middle

Flabellocharajurongica S. Wang and Zhang

-Aclistochara

caii S. Wang-Mesochara

stipitata Assemblage



upper

Minhechara columelaria Wei-Multispirochara subovalis Assemblage

Lower

Aclistochara datongheensis Wei-A.

bransoni Peck Assemblage



Gypsum Gypsum mudstone



11-



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Chapter 80. Biostratigraphy of Paleogene non-marine Ostracoda from East China

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