Secondary Migration of Petroleum Along Axis of Syncline: A Case Study on Southern Kuqa Foreland Basin

Abstract

Tracing petroleum migration pathways is one of the major challenges for exploring of petroleum in a sedimentary basin. The paleo-uplifts are generally considered to be primary migration directions of petroleum. However, here we propose a model that petroleum migrates along the axis of synclines between paleo-uplifts based on geological analysis of integrated seismic, geochemical, and production output data. Detailed seismic data interpretation shows that due to lack of Mesozoic reservoirs or relative low positon or disruption of faults, the paleo-uplifts can hardly be petroleum migration directions. Geochemical parameters, including the ratios of alkyl dibenzothiophenes and wetness parameter, which reflect that maturity of petroleum gradually decreases along axes of synclines between paleo-uplifts from northeastern to southwestern. In addition, petroleum production output and GOR also show a deceasing trend from northeastern to southwestern. All of those evidences suggest that petroleum from the sources in the central and northern Kuqa Foreland Basin, is more likely to migrate along the axes of the synclines between the paleo-uplifts from northeastern to southwestern. This understanding can not only enrich the scientific research on secondary migration, but also be potentially be used to guide petroleum exploration in the southern Kuqa Foreland Basin.

AAPG Datapages/Search and Discovery Article #90291 ©2017 AAPG Annual Convention and Exhibition, Houston, Texas, April 2-5, 2017