塔里木盆地北部一组从碎屑岩到碳酸盐岩的典型层序分析

ANALYSES OF A SET OF SEQUENCES FROM CLASTIC TO CARBONATE ROCKS INNORTHERN TALIMU BASIN

本文对塔里木盆地北部露头剖面中一组从碎屑岩到碳酸盐岩的典型层序进行了详细的沉积学、古生物学和地球化学研究，系统探讨了该剖面中碎屑岩和碳酸盐岩的层序特征，首次发现在具粗碎屑沉积的高能滨岸地带可出现由海进体系域叠五海进体系域的层序叠五方式，这在以前的文献中尚未见报道。对于发育在浅水碳酸盐陆棚背景上的碳醚盐岩层序，各体系域特征明显，易于识别，但在浅水处，密集段不发育。通过对典型层序的详细解剖分析，结合层序地层学的基本原理，探讨了本区从碎屑岩到碳酸盐岩层序的形成机理。

Aset of scquences from clastic to carbonate rocks in Northern Talimu Basin have been studied in sedimentology,paleontology and geochemistry,and the sequence characteristies have been discussed systematically in this paper.A new kind of sequence superposition in the high-ener-gy perezone with coarse clastic deposits has been discoveried for the first time,in which the trans- graessive system tract is superposed with transgressive system tract.As to the carbonate sequences developing on the shallow carbonate platform,the characteristics of system tracts and sequence boundaries are apparent and the sequence can be distinguished easily,but the condensed sections develop poorly Finally,the genesis of this kind of sequences from clastic to carbonate rocks has been discussed according to the theory of sequence stratigraphy and sedimentology.