准噶尔盆地东北缘晚白垩世淡水软体动物群及其地层意义  

LATE CRETACEOUS NON-MARINE MOLLUSCA FAUNA FROM NORTHEASTERN MARGIN OF JUNGGAR BASIN AND ITS STRATIGRAPHICAL SIGNIFICANCE

作　　者：魏景明[1] 

机构地区：[1]新疆石油管理局勘探开发研究院

出　　处：《古生物学报》1989年第4期480-487,573-574,共8页Acta Palaeontologica Sinica

摘　　要：在准噶尔盆地东北缘,西起石树滩,东至北山煤窑,约50km,南北约23km的范围内,零星分布一套红色岩层(插图1)。在北山煤窑等地区,这套红色岩层超覆不整合于中侏罗世含煤地层之上;在距煤窑西北方向约13km处还超覆于中下石炭统之上,形成石炭系天窗。上部倾没于戈壁滩,被第四系所覆盖。自50年代中期,新疆石油管理局地调处部分地质工作者,曾将这套地层的地质时代划为上新世(N2)。直至八十年代初期还一直被沿用着。1982年,我院彭希龄等和中国科学院古脊椎动物与古人类研究所赵喜进。This paper deals with the non-marine molluscan fossils collected partially by Wang Zhi in 1982 and mostly by the writer in 1985 from the northeastern margin of the Junggar Basin in Xinjiang. The fossils were yielded in a suite of red deposits, which has long since been regarded by some geologists as belonging to Pliocene in age. However, based on studies in recent years, it should be assigned to the Late Cretaceous. The fossils described herein include the bivalves Cuneopsis vjalovi Martinson, C. hungsaquanensis Wei and 'Sainshandia' sp.; and the gastropods Hydrobia nemegetensis Martinson, Bithynia jiangjungobiensis sp. nov., Mesclanistes efremovi (Martinson). M. bajanchongorensis Barsbold, M. shuwalovi Martinson and M. mongoliensis (Martinson). Among these fossils the gastropods are similar to those of the Nemeget fauna from the Upper Cretaceous (Nemeget Formation) of Mongolia, while Cuneopsis vjalovi Martinson is distributed in the Yalovatsch Formation (K_2) of the Fergan Basin in USSR. Bithynia jiangjungobiensis sp. nov. (P1. Ⅱ, figs. 16—18) Shell small-sized low, convex and cone-shaped. Spire composed of 4.5—5 convex and smooth whorls. Last whorl larger than the others, with a height a little greater than half the shell. Shell as high as, or a little higher than wide. Suture deep, straight, not oblique. Umbilicus small, partially covered by inner lip. Aperture oval, slightly contracted in upper section. Comparison: This new species resembles Bithynia gobiensis Martinson in the shell shape and in the presence of stelliform whorls, but differs from the latter in the greater number (5.5—6) of whorls and the higher and narrower last whorl. It is also somewhat similar in the conispiral shell and in the number of whorls to Bithynia asiatica Martinson, but in the latter the whorls are more convex and without stelliform ones. Locality and horizon: Oiangjungobi region, northeastern margin of Junggar Basin. Upper Cretaceous Honglishan Formation.

关 键 词：准噶尔盆地 晚白垩世 软体动物群 

分 类 号：Q915.817[天文地球—古生物学与地层学]