High-quality hydrocarbon source rock in the Paleogene sequence of the Ping Chau Formation, Hong Kong
Although petroleum exploration is being conducted in the Hong Kong region, high-quality hydrocarbon source rocks have never been found in this area. The Ping Chau Formation is only Mesozoic-Cenozoic sedimentary rock exposed in Hong Kong and its surrounding areas. The hydrocarbon source rock of the Ping Chau Formation is very rich in organic matters, which has an average total organic carbon (TOC) of 1.9% and chloroform bitumen "A" range from 0.14% to 0.24%. The total hydrocarbon content varies from 880 to 1800 ppm and the transformation ratio is spe- cific from 5 to 9. The index of pyrolytic hydrogen is up to about 600 mgHC/gTOC. These data demonstrate the char- acteristics of the high-quality hydrocarbon source rock. The lamalginite is the major maceral of the source rock of the Ping Chau Formation, and geochemical characteristics also suggest that the organic materials of the source rock are of type I and type II1, with abundant gammacerane, γ, β-carotane and C24 tetracyclic terpane, which indicate that it was formed in the salt water and brackish water sedimentary environment, and the source rock has evolved into a mature phase. The organic inclusions are found within calcite veins in cracks of the source rock, indicating that hydrocarbon has been generated and a secondary migration has happened. The source rock in the Ping Chau Formation is about 200-300 m thick, thus having considerable hydrocarbon potential. The discovery of the high quality hydrocarbon source rock in the Ping Chau Formation will certainly provide insight on hydrocarbon resource exploration in the South China Sea area.
作 者： YAO Suping HU Wenxuan CHEN Longsheng ZHU Dongya XUE Chunyan 作者单位： YAO Suping,HU Wenxuan,ZHU Dongya,XUE Chunyan(Department of Earth Sciences, Nanjing University, Nanjing 210093, China)CHEN Longsheng(Department of Earth Sciences, Hong Kong University, Hong Kong, China)
刊 名： 科学通报(英文版) SCI 英文刊名： CHINESE SCIENCE BULLETIN 年，卷(期)： 2005 50(2) 分类号： P5 关键词： Ping Chau Island Hong Kong Ping Chau Formation high-quality hydrocarbon source rock sedimentary environment