羌塘盆地侏罗系核形石特征及成因探讨

Characteristics and genesis of the oncolites from the Jurassic strata in the Qiangtang Basin

Chengdu Institute of Geology and Mineral Resources, Chengdu 610081, Sichuan, China

摘要: 羌塘盆地侏罗系核形石纹层不发育,只有个别核形石发育不规则的纹层,未发现菌藻类痕迹;核心主要以大小不等的生物碎屑为主;核形石与填隙物都由泥晶方解石组成,只是颜色上有差别。核形石主要产在能量较低的泻湖、局限陆棚环境中。
- 核形石 /
- 纹层构造 /
- 侏罗系 /
- 羌塘盆地
Abstract: Unlike common oncolites,no laminated structures and no algal organisms are observed in the coatings of the oncolites from the Jurassic strata in the Qiangtang Basin.The cores generally contain bioclastics of varying sizes.Both the oncolites and their interstitial materials consist of micritic calcite.The oncolites occur mainly in the lower-energy lagoon and restricted shelf environments.
- oncolite /
- laminated structure /
- Jurassic /
- Qiangtang Basin