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笔者较系统地对松辽盆地三肇地区扶余油层和杨大城子油层(以下简称扶、杨油层)介形类的组合特征、分布范围以及古生态进行了研究。研究表明,扶、杨油层沉积时期的介形类自初期少量出现,之后发展并繁盛,末期全部绝灭。这种变化不仅表现为介形类动物群的属和种数有较大幅度的增加,而且其壳饰类型、分布范围与壳体保存状况也发生了规律性变化,但总体上仍为壳饰简单、属种类型较多、大小个体混生并生活于浅水湖泊环境的介形类群体。对介形类的埋葬环境与分布范围的分析表明,仅含有少量介形类化石碎片的杨五组、杨四组的沉积环境为冲积平原环境,而含有较丰富介形类化石的杨三组—扶上组的沉积环境则以浅湖环境为主,并自杨三组沉积时期在该区中部出现大范围的浅水湖泊后,随着时间的推移,湖泊分布范围与水深在缓慢的扩大或增加,至扶下组沉积时期该湖泊向西已扩大至大庆长垣以西,从而与齐家—古龙地区的湖泊连为一体,组成统一的松辽古湖泊。湖泊水体浅、气候干燥、氧化作用强,可能是造成该时期湖相砂、泥沉积物呈现红色的主要原因。
The author systematically studied the assemblage characteristics, distribution range and palaeoclimate of the ostracods of the Fuyu oil layer and the Yang Dachengzi oil layer in the Sanzhao area, Songliao Basin. The study shows that, during the depositional period of the Fuyang and Yang oil reservoirs, the small amount of ostracods appeared, and then developed and prospered, all of which were extinct at the end of the period. This change not only shows that the genera and species numbers of the Ostomidae increase greatly, but also the shell types, the distribution range and the preservation status of the shell have also changed regularly, but the shell decoration Simple, generous types of species, the size of the individual mixed and living in the shallow lake environment, the orthodox group. The analysis of the burial environment and distribution range of the tectonic classes shows that the sedimentary environment of the Yangshe 5 and Yang 4 groups that contain only a few Ostracoda fossils are alluvial plain environments and the Yangsan group - The depositional environment of the Fu-Shang Formation is dominated by a shallow lake environment. After a large area of shallow lakes appear in the central part of the area during the deposition period of the Yangsan Group, the distribution range and water depth of the lake are slowly expanding or increasing over time During the sedimentation period of the Fuzhong Formation, the lake westward extended to the west of Daqing Changyuan so as to integrate with the lakes of Qijia-Gulong region to form a unified Songliao ancient lake. Lake water body shallow, dry climate, strong oxidation, may be caused during this period lacustrine sand, mud sediments showed the main reason for the red.