Source Kitchen Characterization and Petroleum System History in Tarim Cratonic Basin, China

Feiyu Wang¹, Shuichang Zhang², and Digang Liang^3
1 Petroleum University of China, Beijing, China
² RIPED, PetroChina Company Limited, Beijing, China
³ Research Institute of Petroleum Exploration and Development,CNPC, Beijing, China

Source kitchen characterization is pertinent to petroleum system history analysis. Tarim basin is largest petroliferous basin in China. oils-source rock correlation have proved that petroleum may be mainly originated from lower Paleozoic marine strata, but the organic maturity evolution and hydrocarbon kitchen distribution of Ordovician-Cambrain source rocks are still controversial. According to geochemical screen and organic facies analysis, the prime organic-rich interval exist in lower-middle Cambrian and upper Ordovician, the former distributed in anoxic environment, the latter distributed in the slope with high productivity. The reflectance of vitrinite-like maceral derived from benthic multicellular algae are affective index for assessing the maturity of Ordovician-Cambrian marine source rocks in Tarim Basin, the kinetics of the reflectance of vitrinite-like maceral derived from megascopic benthic multicelluar organisms have been established through hydrous pyrolysis. Maturity distribution and evolution of Ordovician-Cambrain source rocks are delineanatd using BasinMod software calculations data on 250 wells and 340 pseduowells from the 26 seismic profiles. Two lower Paleozoic hydrocarbon kitchens and petroleum system have been identified, the first is lower and middle Cambrian euxenic source rock, located in the Awarti-Majaer depression, the hydrocarbon in the present gigantic Silurian tar sandstone were charged from this kitchen in the late Silurian, the second is upper Ordovicain carbonate mud mound source rock, located in the slope of Tazhong uplift and Tabei uplift to Majaer depression. the hydrocarbon in the Carboniferous and Devonian reservoir were charged from this kitchen in recent 100Ma.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005