川西北广元地区海相层系油苗和沥青来源分析

SOURCE ANALYSIS OF OIL SEEPAGE AND BITUMEN ORIGINATING FROM MARINE LAYER STRATA IN GUANGYUAN AREA, THE NORTHWEST SICHUAN BASIN

饶丹 秦建中 腾格尔 张美珍

Rao Dan Qing Jianzhong Tenger Zhang Meizhen

中国石油化工股份有限公司石油勘探开发研究院无锡石油地质研究所, 江苏, 无锡 214151

Wuxi Research Institute of Petroleum Geology, Exploration and Production Research Institute, SINOPEC, Wuxi, Jiangsu 214151, China

川西北广元地区长江沟剖面寒武系-三叠系中固体沥青大量产出,油气苗丰富,经饱和烃、芳烃生物标志化合物绝对定量分析研究认为,下寒武统固体沥青、泥盆系和下二叠统茅口组油苗饱和烃生物标志化合物特征相似,显示早期有下寒武统烃源充注;三者之间芳烃生物标志化合物特征存在一定差异,除成熟度影响以外,可能后期有上古生界源岩充注.下三叠统飞仙关组油苗饱和烃、芳烃生物标志化合物特征与古生界沥青和油苗存在显著差异,而与上二叠统大隆组具有亲缘关系,也可能有下三叠统源岩的自身供给.

The reservoirs of Cambrian-Triassic from the Changjianggou section contain quantities of solid bitumen in Guangyuan area,the northwest Sichuan Basin.The oil seepage is abundant.It is suggested by research of absolute quantification analysis on the biomarkers of saturated hydrocarbon and aromatics that saturated hydrocarbon biomarker parameters of solid bitumen in Lower Cambrian and seepages in Devonian and Lower Permian Maokou Formation have similar characters.The results show that there is early hydrocarbon filling from Lower Cambrian source rock.There exist certain differences of aromatic biomarkers among them,which is perhaps influenced by late hydrocarbon filling from Upper Paleozoic besides of maturities.There are significant difference in biomarkers of saturated hydrocarbon and aromatics between seepages of Lower Triassic Feixianguan Formation and bitumen and seepages of Paleozoic.There is genetic relationship between seepage in Feixianguan Formation and source rock from Dalong Formation of Lower Permian,which also perhaps originates from Lower Triassic source rocks.

国家重点基础研究发展计划(973计划)项目(2005CB422102)

https://doi.org/10.11781/sysydz200806596