鄂西渝东长兴组礁滩分布及地震相特征

The Distribution and Seismic-facies Characters of Reef and Bank of Changxing Formation in Western Hubei and Eastern Chongqing

王辉

WANG Hui

大庆油田勘探开发研究院勘探规划研究室, 黑龙江大庆 163712

Exploration Planning Research Department of Daqing Oilfield Exploration and Development Research Institute, Daqing, Heilongjiang, 163712, China

晚二叠世鄂西渝东地区为一典型的镶边碳酸盐台地,其中台地边缘和台地内部是礁滩发育的最有利相带。长兴组可划分为2个三级层序。通过层序格架内岩相古地理分析认为,高位体系域是礁滩发育的最有利时期,且礁滩主要发育在Sq1-HST内,同时初步明确了礁滩的展布情况。通过井震结合剖面的地震相追踪与对比认为,礁滩的主要地震相特征为同相轴空白(含极弱振)、断续、杂乱、分叉、前积以及丘状反射等,而且礁地震相的振幅比滩地震相的强。综合研究表明,对区域构造格局和岩相古地理的精细研究,有助于提高礁滩地震预测的精度。

There was a typical rimmed carbonate platform sedimentary system in Western Hubei and Eastern Chongqing in the late Permian, of which the platform margin and the internal of platform are the most favorable places for the development of reef and bank. The Changxing Formation can be divided into two third-order sequences. By the study of lithofacies and paleogeography within the sequence framework, it is believed that the HST is the most favorable development period for reef and bank, and the reef and bank mainly developed in the Sql-HST. In addition, the distribution of reef and bank has been ascertained preliminarily. By seismic facies tracing and correlation of the well-seismic sections, it is believed that the mainly seismic facies characters of reef and bank are blank (including weak amplitude), intermittent, disorder, bifurcation and foreset reflection of seismic event, and the seismic event amplitude of reef is stronger than bank. The comprehensive study of reef and bank reveals that the elaborate research of regional structure pattern and litho-paleogeography is helpful for improving the precision of reef and bank seismic prediction.

https://doi.org/10.3969/j.issn.1008-2336.2012.03.061