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Chapter 82. The Cretaceous ostracod faunas from the Fuxin Basin, Liaoning Province
1-Geological sketch map of the Fuxin Basin of Liaoning Province.
Intrusive rock of
Cretaceous Ostracod Faunas from Fuxin Basin. Chim 1175
Principal f o s s i l s
Principal O s t racoda
m H w
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.
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
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.
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.
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
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.
Y.G. LI, D. Y.Su AND L. J. ZHANG
species from other countries, the age of the Jiufotang Formation is probably from Hauterivian
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.
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
W. Liaoning N. Hebei
Sunjiawan F m ruiingzi F m
Qi ngshi I a
Qingshan F m .
L i anm uxi
J i u f ot ang X i guayuan
Huaj i ying
Laiyang F m .
Val angin i an
.uohe F m
ruchengzi F m .
Wennan F m .
'iiun F m
of non-marine Lower-MiddleCretaceous in different parts of China.
1182 Y.G. LI, D. Y. Su AND L. J. ZHANG
4-Comparative patterns of phase identification.
1, The pattern of phase identification of Cypridea
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
5- 5 s
5- 4 9 8
4 8 0
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.
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.
OF CRETACEOUS OSlRACOD SHELLS FROM THE FUXIN