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塔里木盆地东北部库车以东地区下第三系化石罕见。该地区主要为红色含膏盐的粗碎屑岩沉积。中新世以来 ,由于喜马拉雅运动的影响 ,天山不断隆升 ,导致本区加速沉降 ,出现滨浅湖沉积环境 ,介形类逐渐繁盛。中新世中晚期半咸水介形类 Cyprideis爆发 ,广泛出现Cyprideis占绝对优势的半咸水浅湖环境含膏砂泥岩沉积 ,与东邻柴达木盆地阿尔金山以南地区相似。上新世以来 ,本区沉降速率猛增 ,堆积速率更快 ,基本上处于超补偿沉积 ,湖泊大规模萎缩 ,介形类数量锐减。由于喜马拉雅运动晚期的影响 ,天山山脉库车—库尔勒一线以北的山峰不断隆升 ,本区第四纪湖区规模比上新世大大扩展 ,湖泊范围比中新世显著向南迁移 ,Cyprideis再度繁盛并占优势 ,早更新世晚期距今大约不足百万年 ,本区尤其是库南 1井地区 ,除继续出现丰富的 Cyprideis外 ,突然出现淡水 -微咸水介形类 ,形成一个属种多样的高分异度介形类动物群 ,与柴达木盆地南部昆仑山北麓的介形类组合类似 ,主要有 Candona torosa,Candoniella lactea,Candona neglecta,Candona arcina,Cypridopsis vidua,Limnocythereinopinata,Cypris subglobosa,Ilyocypris gibba,Ilyocpyrisbiplicata,Eucyprisinflata,Candoniellaalbicans,Darwinula sp.,Stenocypris sp.等。
The Tertiary fossils in the east of the Kuqa region in northeastern Tarim Basin are rare. The area is dominated by red gypsum-rich coarse clastic rocks. Since the Miocene, due to the influence of the Himalayan movement, the Tianshan Mountains have been rising continuously, resulting in the accelerated settlement of the area and the depositional environment of the shallow lake and shallow lake. Emerging from the mid-late Miocene Cyprideis, half-saltwater shallow-lake environment containing Cyprideis is widespread with gypsum-sandstone deposits similar to those in the south of the Altun Mountains to the east of the Qaidam Basin. Since the Pliocene, the sedimentation rate in this area soared, the accumulation rate was faster, basically in overcompensated sedimentation, the large-scale atrophy of lakes and the sharp drop in the number of ostracods. Due to the influence of the late Himalayan campaign, the peaks of the Tianshan Mountains Kuqa - north of the Korla line keep rising. The size of the Quaternary Lakes in this area expanded greatly from that of the Pliocene and the scope of the lake moved southward significantly more than in the Miocene. The Cyprideis flourished again And predominate. The early Pleistocene epoch was about less than one million years ago. In this area, especially in the area of Kunan 1 well, in addition to the continuous appearance of Cyprideis, a sudden emergence of freshwater - brackish water-type, forming a species diversity , Which are similar to the orthodox assemblages in the northern foot of the Kunlun Mountains in southern Qaidam Basin. They are Candona torosa, Candona lactea, Candona neglecta, Candona arcina, Cypridopsis vidua, Limnocythereinopinata, Cypris subglobosa, Ilyocypris gibba, Ilyocpyris biplicata, Eucyprisin flata, Candoniella albicans, Darwinula sp., Stenocypris sp. And the like.