孙吴-嘉荫盆地白垩系淘淇河组-太平林场组砂岩主量元素的地球化学特征

沉积盆地中砂岩的地球化学特征主要受物源区控制,碎屑岩的地球化学成分可揭示沉积物的地质信息.笔者通过对孙吴-嘉荫盆地白垩系淘淇河组-太平林场组砂岩的主量元素地球化学特征分析,结合砂岩薄片碎屑成分统计表明:淘淇河组-太平林场组时期物源区的大地构造背景主要为活动大陆边缘,包括大陆岛弧和大洋岛弧.物源区母岩类型主要为花岗岩,中酸性火山岩及低级变质岩.盆地不同位置物源区的大地构造背景和母岩类型有所不同.结合区域地质资料综合分析认为:在淘淇河组-太平林场组沉积时期,小兴安岭仅在太平林场组时期不是盆地主要物源区,而佳木斯地块一直是盆地东部的一个主要物源区.

Geochemistry of major elements from the Cretaceous Taoqihe Formation-Taipinglinchang Formation sandstones in the Sunwu-Jiayin Basin

The geochemistry of sandstones in a sedimentary basin tends to be influenced by provenances,and thus may provide important geological information about the sediments.The analysis of the geochemical signatures of major elements from the Cretaceous Taoqihe Formation and Taipinglinchang Formation sandstones in the Sunwu-Jiayin Basin has disclosed that the source area was once in the tectonic setting of the active continental margin,including continental island arc and oceanic island arc during the deposition of the Taoqihe Formation to Taipinglinchang Formation.The types of parent rocks in the source area include granite,intermediate to acidic volcanic rocks and low-grade metamorphic rocks.During the deposition of the Taoqihe Formation to Taipinglinchang Formation,the Xiaoxing''anling Mountains acted as the main provenance except the deposition of the Taipinglinchang Formation,and the Jiamusi block was always a principal source area in the eastern part of the basin.