塔里木盆地阿克苏沙井子地区康克林组沉积特征

SEDIMENTARY CHARACTERISTIC OF KANGKELIN FORMATION IN SHAJINGZI AREA, AKSU, TARIM BASIN.

塔里木盆地阿克苏沙井子地区康克林组为晚石炭世－早二叠世的一套碳酸盐与陆源碎屑混合沉积物，其岩性自下而上可分为：第一岩性段主要为石英砂岩、粉砂岩夹砾岩和砾屑灰岩；第二岩性段主要为灰岩与细砂岩或粉砂岩互层；第三岩性段主要为生屑灰岩、核形石灰岩夹砂屑灰岩。根据混合沉积物中碳酸盐和陆源碎屑的相对含量及组构特点可将其划分为八种形式：①碎屑岩夹灰岩；②碎屑岩与灰岩互层；③灰岩夹碎屑岩；④陆源碎屑散布于碳酸盐基质之中；⑤碳酸盐作为碎屑岩的填隙物；⑥碳酸盐颗粒散布于陆源碎屑之中；⑦陆源碎屑砾石与碳酸盐颗粒混合沉积；⑧陆源碎屑砾石和碳酸盐颗粒散布于碳酸盐基质之中。通过对混合沉积物形成机制的分析认为，混合物主要形成于潮坪至台地环境，海平面的变化严格控制着混合物的类型，碳酸盐沉积与海平面上升密切相关。

Kangkelin formation in Shajingzi area is mixed carbonate and terrigenous clastic sediments in Late Carboniferous-Early Permian, in terms of relative content and texture characteristic, sediments occurred in following eight types:①clastic rock intercalated with limestone; ②clastic rock interbedded with limestone; ③limestone intercalated with clastic rock; ④terrigenous clastic scattering in carbonate matrix; ⑤carbonate as cements in clastic rock; ⑥carbonate intraclasts distributed in terrigenous clast; ⑦mixed terrigenous gravels and carbonate intraclast sediment; ⑧terrigenous gravel and carbonate intraclasts scattering in carbonate matrix. Based on the analysis of formation mechanism of mixed sediment, it is suggested that the type of mixed sediment is controlled by sealevel changes, and carbonate sediments have close relation to rising of sea level.