青海省南部治多-杂多一带早石炭世有孔虫动物群

在青海省南部的治多—杂多一带1／25万地质填图中，于杂多群中首次发现非筵有孔虫，建立2个组合，即Endothyra-Mediocris—Archaediscus组合和Bradyina-Endothyranopsis组合，地质时代为早石炭世大塘期德坞期，与华南、塔里木盆地、西秦岭、前苏联等地同期生物群可很好地对比，同时结合大冢相似系数的计算表明，青海南部地区在早石炭世属于特提斯大区华夏生物区华南省。

EARLY CARBONIFEROUS FORAMINIFERAL FAUNAS IN THE ZHIDOI AND ZADOI AREA, SOUTHERN QINGHAI

The Early Carboniferous foraminiferal faunas from the Zadoi Group in the Zadoi and Zhidoi area of southern Qinghai Province, found during 1/250 000 geolo-gical mapping, may be divided in an ascending order into the following two assemblages: 1) Endothyra-Mediocris-Archaediscus Assemblage This assemblage dominated by Endothyrinae, mainly genera Endothyra and Mediocris, from the lowest part of the Clastic Formation, the lower part of Zadoi Group. Ten species of Endothyra characterized by having a small test, representing the primitive forms of the genus in the early evolutionary stage, and 4 species of Mediocris flourished in the assemblage, especially in Shenggangwoma, Zhidoi County. Some Archaediscinae appeared first in the assemblage, Permodiscus, ?Parapermodiscus, Archaediscus, Paraarchaediscus. Am-ong them, A. krestovikovi, Pa. koktjubensis were common. The genus Palaeotextularia, with relatively large test and high diversity, was also one of the important elements. The foraminiferal fauna generally is of early to middle Datangian age of the Early Carboni-ferous and may be correlated with the Dainella gumbeica-Plectogyra posneri to Lituotubella glomospiroides-Quasidiscus guangdongensis Assemblage in Guangdong and Hunan and Dainella wushiensis-Endothyra parainflata Assemblage in Tarim Basin.