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生物相及其分区的研究对于川西地区中二叠世—中三叠世的古生物古地理、古板块等特征的恢复具有一定的参考意义。研究区内二叠系—三叠系生物化石丰富,其门类主要有腕足类、珊瑚、蜓类、菊石、牙形石、头足类、双壳类及有孔虫等。研究表明,这些生物门类的分布受沉积环境控制较为明显。在对生物群落划分和研究基础上,根据其与沉积特征的组合规律,在研究区识别出6种类型的生物相。通过对生物的生态类型、产出岩性以及对应沉积相类型等分析的基础上,建立了研究区中二叠世—中三叠世生物相模式,并详细阐述了各类型生物相中的生物类别以及典型群落等特征和含油性特征。根据生物的生态、地理分布特征及生物相在时间和空间上的组合规律,将川西地区中二叠世—中三叠世划分为3个生物相区,认为台地生物相区受控于扬子台地的发展,盆地生物相区受控于龙门—松潘海槽的发育。生物相类型的分布特征表明,台地型和缓坡型生物相主要分布于研究区的主体区域,体现了其分布主要受控于扬子台地,而深水盆地型生物相则主要分布于研究区边缘区域,反映出其分布主要受控于其北部的龙门海槽。
The study of biofacies and their zoning has some reference significance to the restoration of Paleo-paleontology, paleofacies and other features from Middle Permian to Middle Triassic in western Sichuan. The Permian-Triassic biological fossils are abundant in the study area. The main categories are brachiopods, coral, dragonflies, ammonites, conodonts, cephalopods, bivalves, and foraminifera. Research shows that the distribution of these biota is more controlled by sedimentary environment. Based on the division and study of biomes, six types of biotransformations were identified in the study area according to their combination with sedimentary characteristics. Based on the analysis of biological types, lithology of output and the types of corresponding sedimentary facies, the Middle-Permian-Middle Triassic biofacies model has been established in this study region. The biological facies of various types of biological facies Categories and typical community characteristics and oily characteristics. According to the biological and geographical distribution characteristics of the organisms and the combination of time and space in the biological facies, the Middle Permian-Middle Triassic in the western Sichuan area is divided into three biological facies zones, and the terrestrial biological facies zone is controlled by the Yangtze Platform The development of the biological phase of the basin is controlled by the Longmen-Songpan Trough. The distribution characteristics of the biofacies indicated that the terrestrial and gentle-slope biofacies were mainly distributed in the main area of the study area, indicating that the distribution was mainly controlled by the Yangtze platform, while the deep-water basin-type biofacies mainly distributed in the marginal area of the study area. Reflects its distribution mainly controlled by its northern gantry trough.