摘要
华北北部蓟县系洪水庄组是我国华北地区中、新元古界有机质相对富集的地层，其有机碳含量高值可达13％～20％。其岩性旋回特征表明，洪水庄组页岩形成时期水体滞留，水平循环较弱；同时，有机碳、硫含量特征表明，洪水庄组为好的烃源岩，具有较大的生烃潜量。华北北部洪水庄组有机显微组分特征研究结果表明，由于中、新元古界生物类型单一，洪水庄组有机显微组分构成简单，以大量藻类体和腐泥质碎屑为主，藻类体数量上的爆发为富有机质沉积的形成奠定了物质基础；页岩中类镜质体的发现验证了类镜质组属菌藻类成因的观点，这对于寻找前泥盆纪海相地层有机质热演化参数具有重要意义。页岩裂隙中含大量油珠，表明洪水庄组菌藻类生源的有机质经历了有效的生、排烃过程。形成于14亿年前的洪水庄组应为迄今为止我国已知最古老的、并经历有效排烃的富有机质沉积。
The Hongshuizhuang Formation of the Jixian System in northern North China is a typical formation relatively rich in organic matter in the Mesoproterozoic and the Neoproterozoic strata. Its TOC can be up to 13 %- 20 %. Its features of lithologic cycle show that the Hongshuizhuang Formation shale was deposited in stagnant water body with weak horizontal circulation. And other characteristics such as organic carbon and sulfur content suggest that the formation contains high-quality source rocks with large hydrocarbon-generation potential. A study of the organic maceral characteristics of the formation indicates that the Mesoproterozoic and the Neoproterozoic feature in single biotic formation, and that the organic maceral compositions of the Hongshuizhuang Formation are simple with alginite and sapropelinite debris in predominance. The rapid increasing of alginite provide the material foundation for organic matter rich deposits. The discovery of provitrinite in the shale confirms the view that the provitrinite is of thallogen origin, providing an important clue for selecting thermal evolution parameters for the pre-Devonian marine strata. The existence of a large number of oil droplets in the shale cracks show that the organic matter of thallogen origin in the Hongshuizhuang Formation had gone through effective hydrocarbon generation and expulsion. The Hongshuizhuang Formation with an age over 140 Ma is the oldest organic rich deposits discovered so far in China that had experienced effective hydrocarbon expulsion.
出处
《石油与天然气地质》
EI
CAS
CSCD
北大核心
2010年第3期367-374,共8页
Oil & Gas Geology
基金
国家重点基础研究发展计划(“973”计划)项目(2006CB202300)
关键词
有机碳
类镜质组
海相镜质组
显微组分
洪水庄组
中元古界
华北北部
organic carbon, provitrinite, marine vitrinite, maceral, Hongshuizhuang Formation, Mesoproterozoic, northern North China
