华北中—西部地区晚石炭世太原组碳酸盐岩沉积环境

DEPOSITIONAL ENVIRONMENTS OF CARBONATE ROCKS OF THE LATE CARBONIFEROUS TAIYUAN FORMATION IN THE WEST-CENTRAL PART OF NORTH CHINA

本文对岩心和露头剖面进行了详细的观察和分析,提出太原组灰岩为潮坪环境,并依据相标志划分出潮上、潮间、潮下、潮汐水道和风暴沉积五种微相类型;进而阐述了潮坪灰岩在陆表海背景下,随着海平面的波动,在清水与浑水交替下的沉积过程,及其受火山作用、风暴作用和水系的干扰与影响;最后,对碳酸盐形成时的古纬度等作一简要分析。

On the basis of a detail observation and analysis of cores and outorop sections it is proposed that limestones of the Taiyuan Formation were deposited in tidal flat environments. According to the facies markers, five types of micro-facies may be distinguished: supratidal, intertidal, subtidal, tidal channel and storm deposits. The tidal flat limestones were deposited under the conditions of alternation of clear water and turbid water with the fluctuation of sea-level in an epicontinental sea and were subjected to the interference and influence of volcanism, storms and river systems. Finally, the paper gives a brief analysis on the palaeolatitudes during the formation of carbonate rocks of the Taiyuan stage.