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塔里木盆地西南斯木哈纳剖面上白垩统海相地层发育完整,产丰富的双壳类、腹足类、有孔虫、介形虫等化石。本文主要对该剖面中产自库克拜组的双壳类化石进行鉴定、分析,其自下而上可划分出三个生物组合:Flaventia ovalis-Cardita sp.,Ostrea oxiana-Ostrea vatonnoides-Ostrea nummus和Rhynchostreon suborbiculatum-Lima marrotiana-Pycnodonte(Costeina)costei。通过对双壳类化石进行洲际对比,将库克拜组的时代归为于Albian晚期—Turonian早期。对库克拜组双壳类生物群落的古生态分析表明,斯木哈纳地区Albian晚期至Turonian早期经历了一次海侵,海侵规模在Turonian早期(库克拜组上段中上部)达到最大。
The Cretaceous marine strata in the western Hannaean Muhan section of the Tarim Basin are well developed and rich in fossils such as bivalves, gastropods, foraminifera and ostracods. In this paper, we mainly identify and analyze the bivalve fossils from the Kuqa Formation in this section. There are three biological combinations from the bottom up: Flaventia ovalis-Cardita sp., Ostrea oxiana-Ostrea vatonnoides-Ostrea nummus And Rhynchostreon suborbiculatum-Lima marrotiana-Pycnodonte (Costeina) costei. Based on the intercontinental comparison of bivalve fossils, the Kuqa Formation was assigned to the late Albian-Early Turonian. The paleoecological analyzes of the Baker biota from the Cookkay Formation show that an early transgression from Albian to Turonian occurred in the Swimhanna region and that the transgressive scale reached the maximum in the early Turonian (upper middle part of the Cookkai Formation).