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Chapter 82. The Cretaceous ostracod faunas from the Fuxin Basin, Liaoning Province

Chapter 82. The Cretaceous ostracod faunas from the Fuxin Basin, Liaoning Province

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1174



Rivers



p-1



F- Fl



Dislocation



Occurrence



Angular

unconformi ty



H E

Railroads



Village Road



TEXT-FIG.

1-Geological sketch map of the Fuxin Basin of Liaoning Province.



Intrusive rock of

Lower Cretaceous



Cretaceous Ostracod Faunas from Fuxin Basin. Chim 1175



Principal f o s s i l s



Principal O s t racoda



e rAppndicisporilrr



1"691

Sand-gravel



Conglomerate



Sandy

conglomerate



Sillstone



m H w



Argillaceous

sandstone



Argillaceous

siltstone



Tuff

sandstone



Andesite



Basanitoid



Lens



-



- -



Mud-shale



Shale



Coal seam



Andesite-breccia



TEXT-FIQ.

2-Composite column of the Jurassic-Cretaceous system in the Fwin Basin.



The Fuxin Formation, conformably overlying the Jiufotang Formation, is represented by

lacustrine swamp deposits composed mainly of grey, greyish-white conglomeratic sandstone,

conglomerate, sandstone and greenish-grey siltstone, sandy-shale, and dark grey mudstone with six

intercalated coal-measure units. It yields abundant fossil plants such as Rufordia geopperti, the

pollen and spores Cicatricosisporites-Appendicisporites-Triporoletes and sparse bivalves such as

Spherium anderssoni and Nippononaia sinensis as well as some ostracods. The ostracods mainly

include Cypridea unicostata, C. (C.) yabulaiensis, C. (Pseudocypridina) globra, C. (P.) haizhouensis, Ziziphocypris simakovi, Z . costata, Pinnocypridea dictyotroma, Candona? dungliangensis and

Candoniella simplica etc. The thickness of this formation is approximately 1200 metres.

The Sunjiawan Formation is characterised by fluvio-lacustrine deposits, consisting mainly of

purplish-red and variegated conglomerate, sandy-conglomerate, sandstone, siltstone and mudstone,

lying conformably upon the Fuxin Formation with a total thickness of about 100 metres. The

sandstone, siltstone and mudstone contain sparse plants, the pollen and spores SchizaeoisporitesEphedripites, gastropods and ostracods. The Ostracoda consist of Cypridea (Bisulcocypridea)

edentula tumidula, Rhinocypris pluscula,Triangulicypris longissima, Candona praevara and Cyclocypris invalida.



1176 Y. G,LI, D. Y. SU AND L. J. Z H A N ~



For more than half a century, many Chinese and foreign geologists have conducted a lot of

investigations in this district. Their research results have provided valuable data for present-day

geological and stratigraphical studies. In recent years, great endeavours have been made in this

field by the Shenyang Institute of Geology and Mineral Resources, the Regional Survey Party

of the Liaoning Geological Bureau, the 107 Geological Party of the Liaoning Corporations of Geology and Coal Field Exploration and the Haizhou Coal Mine Bureau, with encouraging results.

In the ostracod studies of this district, Hou Youtang (1958) described and illustrated 2 new species of Cypridea from the upper part of the Jiufotang Formation; Hao Yichun (1962) studed some

ostracod species from the Jiufotang Formation and the Fuxin Formation in an unpublished scientific report; Chen Deqiong (1965) described a new genus Ziziphocypris from the upper part of the

Jiufotang Formation; and Su Deying et al. (1981) studied some species of Ostracoda from the

Yixian Formation and the Jiufotang Formation of western Liaoning. Some species of ostracods

from the Jiufotang Formation and the Fuxin Formation have been described and illustrated

by Zhang Lijun (1982, 1984); Dai Hanlin and Ge Yuhua (1984) drew up a fossil list of the

Cretaceous ostracods from the Fuxin and Zhangwu regions.

The above-mentioned geological, stratigraphical and ostracod studies are undoubtedly very

conducive to the further study of the Cretaceous ostracods in the Fuxin Basin.



OSTRACOD

ASSEMBLAGES

The Cretaceous ostracods in the Fuxin Basin are abundant and dominated by numerous species

of Cypridea. Based on the difference in taxa and their stratigraphical distribution, four ostracod

assemblages are recognized as follows :

The assemblage of the Yixian Formation (Assemblage 1) is relatively abundant. The genus

Cypridea is represented by the following forms:

a) The medium-sized, spinose, punctate-shelled form Cypridea venustata with a subtrapezoid

profile, which is similar to Cypridea dunkeri carinata from the Middle Berriasian in northern German

Democratic Pepublic (Wienholz, 1968) and from the middle Purbeck Bed in southern England

(Anderson, 1971); it also bears a resemblance to Cypridea accommodata from the Lower Cretaceous

in eastern Mongolia.

b) The high-shelled, large, punctate, multi-spinose and tuberculate species Cypridea ganhzaoensis

resembles Cypridea tuberculata longtonensis from the Middle Purbeck Beds in southern England

(Anderson, 1971) and from the Berriasian in northern Spain (Brenner, 1976). It is also similar to

Cyprideajonesi (Wolburg, 1959) from Wealden 4 Bed in northwestern Germany and has a close

resemblance to Cypridea regia (Lubimova, 1956) from Lower Cretaceous deposits in eastern

Mongolia.

PLATE1- Fig. 1. Cyprideu venustatu Su and Li. Lateral view of right valve (LY8421, DLWl1, Yixian Formation)

X 48. Fig. 2. Cypridea sulcata Mandelstam. Lateral view of right valve (LY8422, DLW12, Yixian Formation)

X40. Fig. 3. Cypridea gunzhuoensis Su and Li. Lateral view of right valve (KZ8451, DLW13, Yixian Formation)

~ 4 0 Fig.

. 4. Cypridea regia Lubimova. Lateral view of right valve (OL8112, Jiufotang Formation) ~ 3 4 Fig.

.

5 . Cypridea vitimensis Mandelstam. Lateral view of left valve (BG8491, DLWlS, Jiufotang Formation) X40.

Fig. 6. Cypridca justa Lubimova. Lateral view of right valve (OL8115, Jiufotang Formation) X36. Fig. 7.

Cypridca (C.)

veridicu arquaia Zhang. Lateral view of right valve (ZC8471, DLW14, Yixian Formation) ~ 4 0 .

Fig. 8. Cypridea koskulensis Mandelstam. Lateral view of left valve (OL8113, Jiufotang Formation) X48.

Fig. 9. Cyprideu unicostuta Galeeva. Lateral view of right valve (OL816, Jiufotang Formation) X36. Fig. 10,

Cypridea prognuta Lubimova. Lateral view of right valve (OL818. Jiufotang Formation) X 36. Fig. 11. Cyprideu

(Ufwelfia)ihsienensis Hou. Lateral view of left valve (OL8114, Jiufotang Formation) X 36. Fig. 12. Cyprideu

(C.) rosrelfa Zhang. Lateral view of right valve (YJ848x, DLW16, Jiufotang Formation) X40. Fig. 13.

Cypridca (C.)

veridivu veridiva Zhang. Lateral view of left valve (YJ8496, DLW17, Jiufotang Formation) X42.



1178 Y.G . LI, D. Y.SU AND L. J. ZHANQ



c) The medium-sized, smooth, uni-spinose form Cypridea sulcata is very close to Cypridea

bispinosa bimammata (Wolburg, 1959), and Cypridea spinigera (Neale, 1971). Other genera such as

Lycopterocypris infantilis and Darwinula contracta, which have been found in the Lower Cretaceous

of other districts of China, the USSR and MNR, are also abundant in this basin. Based on the

characteristics of Assemblage 1 and their resemblance to known species found in other countries,

the plausible age for the Yixian Formation is from Middle Berriasian to Valanginian. In addition,

volcanic samples for isotopic studies were collected from the bottom of the Yixian Formation,

west of Zhuanchengzi, and the result of Rb-Sr isochron dating gives 140 M.Y. while K-Ar isochron

dating gives 136.9 M.Y. The palaeomagnetic determination made with samples from the same

locality and horizon showed the palaeomagnetic pole to be at 148.9”E longitude and 65”N

latitude. According to both isotopic data and palaeomagnetic determination, the Yixian Formation

should be Early Cretaceous in age (Wang Dongfang, 1982,1983).

The assemblage of the Jiufotang Formation (Assemblage 2) is abundant. The genus Cypridea

includes the following species:

a) The medium-sized, sparsely tuberculate form Cypridea vitimensis with an anterodorsal node

is widely distributed in the Barremian of the Vitimu Basin and Baikol region of USSR, eastern

Mongolia and other regions of China. This species resembles Cypridea granulos protogranulosa

(Anderson, 1971) from the Middle Purbeck Beds of southern England.

b) The inverse, medium-sized, punctate form Cypridea koskulensis with well-developed cyathus is

widely distributed in the Far East and W. Siberia and Kazakh province of USSR, eastern Mongolia

and other regions of China. This form resembles Cypridea bogdenensis and Cypridea valdensis

which have been found in southern England (Kilenyi and Neale, 1978), the Cretaceous of the

Paris Basin (Oertli, 1963) and the Wealden 4 Beds in northwestern Germany (Wolburg, 1959).

c) The small, tuberculate, spined form Cypridea just with a marked anterodorsal angle; the

medium-sized, multi-tuberculate species Cypridea regia with a marked anterodorsal angle; and

the large, punctate, large-beaked form Cypridea prognata with marked cyathus, have all been

reported from the Barremian of eastern Mongolia (Lubimova, 1956).

d) Besides the species of Cypridea, this assemblage also contains Rhinocypris echinata and

Ziziphocypris costata which are widely distributed in the Barremian of the W. Siberia and Kazakh

province of USSR, eastern Mongolia and other regions of China.

e) The large, smooth, subtriangular shelled form Cheilocypridea trapezoidea with a marked

“anterior lip” is very like Mantelliana? uniensis (Brenner, 1976) from the Barremian-Aptian in

northeastern Spain.

Based on the characteristics of Assemblage 2 and their resemblance to known Cretaceous

PLATE2-Fig. 1. Lycopterocypris infantilis Lubimova. Lateral view of right valve (LY8423, DLWl8, Yixian Formation) ~ 4 0 Fig.

. 2. Durwinulu contructa Mandelstam. Lateral view of right valve (LY8424, DLW19, Yixian

Formation) x 40. Fig. 3. Rhinocypris pluscula Li. Lateral view of right valve (SG130158, Sunjiawan Formation)

x 60. Figs. 4, 5. Timiriuseviusp. 4. Lateral view of right valve; 5. Dorsal view of carapace (DL8441, DLW20,

Fuxin Formation) ~ 4 0 Fig.

.

6. Ziz&hocypris simukovi (Mandelstam). Lateral view of right valve (DL8442,

DLW 21, Fuxin Formation) x 40. Fig. 7. Ziziphacypris costutu (Galeeva). Lateral view of right valve (DL8443,

DLW22, Fuxin Formation) ~ 4 0 Fig.

. 8. Cundonu sp. Lateral view of left valve (SJ8461, DLW23, Sunjiawan

Formation) x 40. Fig. 9. Lycopterocypris circulutu Lubimova. Lateral view of right valve (SG130220, Jiufotang

Formation) ~ 4 8 Fig.

.

10. Cundoniellu simplicu Zhang. Lateral view of right valve (DL6444, DLW24, Fuxin

Formation) X 40. Fig. 11. Cheilocyprideu trupezoideu Zhang. Lateral view of right valve (OL8127, Jiufotang

Formation) X 37. Figs. 12,13. Cypridea (Bisulcocyprideu) edendula tumidula Zhang. 12. Lateral view of right

valve; 13. Dolsal view of carapace (SG130103, Sunjiawan Formation) ~ 4 9 Fig.

.

14. Rhinocypris echinutu

(Mandelstam). Lateral view of right valve (OL130157, Jiufotang Formation) x 60. Figs. 15,16. Limnocypridea

jianchungensis Su and Li. 15. Lateral view of right valve; 16. Dorsal view of carapace (JC8431, DLW25,

Jiufotang Formation) X 40. Fig. 17. Limnocyprideu grammi Lubimova. Lateral view of right valve (SG130129,

Jiufotang Formation) X 36. Fig. 18. Limnocypridea ubscondidu Lubimova. Lateral view of right valve

(SG130127, Jiufotang Formation) x 36.



1180



Y.G. LI, D. Y.Su AND L. J. ZHANG



species from other countries, the age of the Jiufotang Formation is probably from Hauterivian

to Barremian.

The assemblage of the Fuxin Formation (Assemblage 3) is represented by sparse species of the

genus Cypridea and several forms of other genera such as :

a) The medium-sized, subtriangular, smooth-shelled, flat-ventered Cypridea (C.) yabulaiensis,

which has been found in the middle Cretaceous of Mongol autonomous region in China.

b) The large, smooth-shelled,small-beaked Cypridea (Pseudocypridina)?globra has been reported

from the Lower-Middle Cretaceous of Gansu and Ningxia in China.

c) The small, flat-shelled Ziziphocypris costata and Z . simakovi with distinct striated ornamentation are widely distributed in the Middle Cretaceous of other parts of China, eastern Mongolia

and W. Siberia and Kazakh province of USSR.

d) In addition, there are species of the Cenozoic genera Candona and Candoniella in this assemblage. Based on the characteristics of this assemblage and the geological distribution of the

known species, the Fuxin Formation could be of Barremian to Aptian age.

In the assemblage of the Sunjiawan Formation (Assemblage 4) the ostracod fauna is limited.

a) The genus Cypridea is represented by several small-shelled,bisulcate forms such as Cypridea

(Bisulcocypridea) edentula tumidula. The species of the subgenus Bisulcocypridea have been found

in the non-marine middle and Upper Cretaceous to Lower Tertiary of America, Asia and Africa.

b) Other than very few species of Cypridea, this assemblage also contains Rhinocypris pluscula

and several Cenozoic forms such as Candona praevara and Cyclocypris invalida. Based on the

characteristics of this assemblage and the geological distribution of the known species, the Sunjiawan Formation can be Aptian to Albian in age.



FACIES

PRELIMINARY

ANALYSIS

Based on sedimentary and palaeontological characteristics and geochemical data, the Cretaceous strata in the district studied could be roughly subdivided into the following four sedimentary

facies : shallow lacustrine deposits, lacustrine deposits, lacustrine-swamp deposits and fluviolacustrine deposits.

The shallow lacustrine deposits, accumulated in a reducing environment, are represented by the

Jingangshan Bed of the Yixian Formation, and mainly distributed in Jingangshan, Toutai, Yusi

and Zidutai. The rocks are mainly siltstone and fine granular sandstone, with intercalated thin beds

of shale, showing flat bedding and minor cross bedding in moderate thickness. The greyish-white

tuffaceous shale in the lower part of the Jingangshan Bed yields abundant specimens of the lacustrine bivalve Nakamuranaia chingshanensis, the conchostracan Eosestheria jingangshanensis,

Insecta Ephemeropsis trisetalis, Pisces Lycoptera muraii and well-preserved ostracods in very low

diversity and high abundance. Ostracoda are dominated by Cypridea forms of Cyprididae with very

sparse Cytheridae. The ornamentation of these ostracods is generally not strong. They are characterised by smooth or punctate, finely-reticulate and small spinose shells, the hinge is adont and

lophodont, and sieve-type normal pores and eye spots are absent.

Trace-element analysis of the ostracod shell of Cypridea (C.) veridica arquata by emission spectrometry (after analyst Chen Shanke) shows that the B content is less than 1 ppm (less than 0.001 %)

while laser spectrometry (after analyst Duan Yuran and Li Wei hua) shows that the Mg content is

2%, Fe is 0.5 %, Ca is 47 %, Sr is 0.5 %; Sr/Ca ratio is 0.012, and the Ca/Mg ratio is 23.5. Analysis

of Lycopterocypris infantilis using the same method shows that the Mg content is 2 %, Fe is 0.3%,

Ca is 38%; Ca/Mg ratio is 19.000 and the Sr/Ca is 0.005. .

The phase identification of the powder of the ostracod shells of Cypridea (C.) veridica arquata



Timi



-



W. Liaoning N. Hebei



Shandong



W. Zheiing



N. Shanxi



Zhungeer



European



(M.Y.

Sunjiawan F m ruiingzi F m



Hengshan

Aptian



---



LD

4

0



Lamawan



I



Fm.



00

3

0



Qi ngshi I a



F m.



Qingshan F m .



L i anm uxi



/Fm.

Fm .



J i u f ot ang X i guayuan



F m.



Fm.



---



- --___



Yixian



F m.



Huaj i ying

Fm.



J ingchuar

Fm .

Luohan

iong Fm.



Laiyang F m .



bj

-



Barremian



Hauterivian



HuanheHuachi



Fm.



Val angin i an



.uohe F m



Laocun



Dabeigou



h



2



Fm.



I



0

cy

r.



-



1

ruchengzi F m .



TEXT-FIG.

3-Correlation



Baiqi Fm.

hangjiakou



Fm



-cuyv.



Wennan F m .



'iiun F m



Berriasian



---t'--I



Houcheng



F m.



of non-marine Lower-MiddleCretaceous in different parts of China.



1182 Y.G. LI, D. Y. Su AND L. J. ZHANG

xt03



4.5R

4.88



3.93

3.00

2.50



1



1.-



t .RR



8.w



ie.8



a.e



18.0



TEXT-FIG.

4-Comparative patterns of phase identification.



48.8



50.0



1, The pattern of phase identification of Cypridea



(C.)

veridicu urquutu from the Jinganshan Bed of the Yixian Formationat Zaocishan of Yixian; 2,The pattern

of CaCO,; 3 , The pattern of a-SiOz.



by X-ray diffraction (after analyst Zhu Xiaoling) shows a large amount of CaCO, with very little

a-SiOz, as shown in Text-fig. 4.

The lacustrine deposits of a reducing environment are represented by the Jiufotang Formation,

mainly at Nihezi in Yixian. The rocks are mainly mudshale, siltstone and sandstone with

intercalated thin coal seams, oil shale and asphalt, showing paper flat bedding witha total thickness of several hundred metres. They contain abundant specimens of the lacustrine bivalve Nakamuranala Chingshanensis, Gastropoda Viviparus spp., Conchostracan Eosenstheria middendorfii,

Insecta Ephemeropsis trisetalis, Pisces Lycoptera spp. and well-preserved ostracods which are

dominated by Cypridea species of the family Cyprididae, while forms of the family Cytheridae

are very sparse. The ornamentation of these ostracods is smooth or punctate and reticulate; sievetype normal pores and eye spots are absent. The hinge is lophodont or adont.

Trace-element analysis of the ostracod shell of Cypridea (C.) veridica veridica by laser spectrometry shows that the Mg content is 14%, Fe is 1 %, Ca is 34%, Sr is 0.3 %; Ca/Mg ratio is 2.420

and Sr/Ca is 0.0088. Analysis of Limnocypridea jianchangensis using the same method shows that

the Mg content 2%, Fe is 2%, Ca is 37%, Sr is 0.2; Ca/Mg ratio is 18.500 and Sr/Ca is 0.005.

The phase identification of the powder of the ostracod shells of Cypridea (C.) vefidica veridica

by X-ray diffraction shows a large amount of CaMg(C03)z with very little CaC03 and a-SiOz,

as shown in Text-fig. 5.

The lacustrine-swamp deposits accumulated in a reducing environment and are represented by

the Fuxin Formation, and mainly distributed round Haizhou and Dong liangzhen in Fuxin. These

rocks consist mainly of sandstone and mud-shale showing flat bedding and cross bedding. The up-



Cretaceous Osiracod Faunas from Fuxin Basin, China 11 83



10.0



20.8



38.8



48.0



5E.E

CacO3

5- 5 s



413.8

2B.e



1m.e



4



80.8



6e.R



s102

5- 4 9 8



-



4 8 0

28.8



TEXT-FIG.

5-Comparative patterns of phase identification. 1, The pattern of phase identification of Cypridea

(C.)veridicu veridiva from the Jiufotang Formation at Yujiagou in Yixian; 2, The pattern of CaMg(C03)z;

3, The pattern of CaCO,; 4, The pattern of a-SiOz.



per part is greyish-whitesandstone and conglomerate, the middle part greyish-black, greyish-green

sandstone and mud-shale with six thick coal seams, and the lower part greyish-yellow sandstone

with intercalated conglomerate. These deposits yield abundant plants (Rufordia geopperti) and

pollen-spores (Cicatricosisporites-Appendicisporites-Triporoletes), sparse vivalves (Spherium andersson, Nippononaia sinensis) and ostracods including species of Cypridea, Candoniella and

Ziziphocypris. Their ornamentation is smooth or distinctly striated; the hinge is generally adont

or lophodont and sieve-type normal pores and eye spots are absent.

Analysis of the trace elements of the ostracod shell of Limnocypridea qinghemenensis by laser

spectrometry shows that the Mg content is 1 %, Fe is 8 %, Ca is 40 %, Sr is 0.8 %; Sr/Ca ratio is 0.02

and Ca/Mg ratio is 40. Analysis of Ziziphocypris simakovi using the same method shows that the

Mg content is 2%, Fe is 8%, Ca is 40%, Sr is 0.3 %; Sr/Ca ratio is 0.007 and Ca/Mg is 20.

The phase indentification of the powder of the ostracod shells of Ziziphocypris simakovi by X-ray

diffraction shows a large amount of CaCO, with very little Cu-SiO, and FeS,, as shown in Textfig. 6.

The fluvio-lacustrine deposits are represented by the Sunjiawan Formation, and mainly distributed round Sunjiawan in Fuxin and Badaohau in Yixian. These deposits are composed of purplish-red conglomerate with intercalated thin beds of sandstone and mud-shale with major cross

bedding. The gravels have not been very well sorted and rounded. Grain size of the sediments becomes finer and finer upwards and their thickenss may range from hundreds of metres to more

than one thousand metres. The deposits have retained their purplish-red colour because the

anhydrous ironstone has not been hydrated in the sedimentary process.



1184



1RR.8

88.8



2



id03

5- 586



:::;

20.0



2e.e



38.8



48.8

FeS;!



3

24- 76



4



-48.A

a-e

28.8



18.8



28.8



30.8



40.8



58.8



TEXT-FIG.&Comparative pattern of phase identification. 1 , The pattern of phase identification of Ziziphocypris simukovi from the Fuxin Formation; 2, The pattern of CaCO,; 3, The pattern of a-Si02; 4, The pattern of FeS2.



TABLEI-TRACE-ELEMENTS

OF CRETACEOUS OSlRACOD SHELLS FROM THE FUXIN

BASIN.



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Chapter 82. The Cretaceous ostracod faunas from the Fuxin Basin, Liaoning Province

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