新疆伊犁盆地介形类化石研究

STUDY ON THE OSTRACOD FOSSILS OF THE ILI BASIN,XINJIANG,NORTHWEST CHINA

伊犁盆地为北天山与南天山所夹持的山间盆地(复合型盆地),受多期构造运动的影响,前二叠纪基底经历了裂谷、坳陷和隆升三个阶段;由于受构造运动影响较大,盆地面积小,稳定性差,地层分布不均,古生物化石较贫乏。通过生物地层研究,石炭系—新近系介形类化石的丰度与分异度均较低,并建立相应介形类化石组合,结合其它门类化石研究,理顺了生物群序列,以及各岩组与化石组合的对应关系,为盆地的地层划分与对比提供了古生物依据和重要的参考价值。

The Ili basin is a composite basin between the northern and southern Tianshan mountains, with a pre-Per- mian basement. Due to significant impact of the tectonic movements, the basin area is small, with unstable and unevenly distributed strata containing meager fossils. It is found that Carboniferous-Neogene ostracod fossils are low in abundance and diversity. Through the study of ostracods in combination with other fossils, the sequence of the fossil biota was set up and the relationship between the strata and fossil assemblages was clarified, which provide important basis for the stratigraphic subdivision and correlation in this area.