塔里木盆地北部三叠纪孢粉植物群及层序地层的划分

TRIASSIC PALYNOLOGY AND DIVISION OF SEQUENCE STRATIGRAPHY FROM NORTHERN TARIM BASIN

依据对塔里木盆地北部库车河剖面及沙１１井和沙３２井三叠纪地层和孢粉学的研究，将本区三叠纪孢粉划分为８个孢粉组合。其中，早三叠世２个组合，中三叠世３个组合，晚三叠世３个组合。三叠纪地层除产有丰富的孢子花粉外，在不同层位还有不同丰度和分异度的疑源类、轮藻、介形虫及植物化石等。依据不同层位中各类生物的不同丰度，建立了１１个生物埋藏群落，它们反映了不同的生态和埋藏环境。按照这些生物埋藏群落在剖面纵向上的演变，将塔里木盆地北部三叠纪地层划分为９个三级地层层序。

According to the detail study for Triassic palynoflora from the Kuche River section and two wells Sll and S32 in northern Tarim Basin, eight palynological assemblages are established, in which two assemblages belong to Early Triassic, three assemblages to Middle Triassic and two assemblages to Late Triassic. Despite of the spore and pollen, different abundantal acritarch, charophyta, ostracoda and plant fossils were found in the Triassic deposit from the Kuche River section. From the abundance and diversity of fossils in individual layer, eleven thanatocoenoses are recognized in this study. On the basis of vertical evolution of thanatocoenose from the Kuche River section the Triassic strata are divided into nine third orders of sequence stratigraphy, and therefore the relative change of lake level during Triassic in Tarim Basin is recovered.