The Study Of Petroleum Migration And Accumulation ＆ Conservation Conditions In North Rim Of Chaidamu Basin

Based on the study of formation distribution, structure evolution, result of reservoir evaluation, character of trap development, studies the petroleum migration and accumulation conditions in north rim of Chaidamu basin.The main direction and position of petroleum secondary migration is up to potential distribution of fluid. By the simulation computation of the developing profile of palaeofluid potential and the six main conducting path plans of Lulehe formation (period of nowadays, N23, N22,N N E3), discovered that Eboliang, Yahu. LenghuMahai structure belts are low potential area in long stage which are petroleum migrating direction area. The main pathways of petroleum secondary migration are sandstone, fault surface and unconformity surface. By contrasting the geochemistry indicator between proved reservoir and source rock, confirm the migrating direction of petroleum. Based on the homogenization temperature of inclusive, confirm two migrating periods existing.By studying the characters of fluid potential in different stages, genetic relationship contrasting between oil and source, and structural feature analysis, conclude the petroleum migration and accumulation pack is varied from one to seven since Oligocene which are Saishiteng fore mountain. Yuqia, Lenghu. Mahai-Nanbaxian, Eboliang-Hulushan, Yahu-Yikeyawuru and Beilingqiu-Wudong.The main seal mechanism of tertiary claystone formation is property mechanism and the next is excess pressure mechanism. Using LOGES evaluation system, evaluate the microscopic seal ability of claystone formation in study area. And using standard breakthrough pressure of sample, incorporation with macrofeature as lithologic, sediment phase, thickness, continuity and so on, comprehensive evaluate the seal ability of every seal formation. The claystone seal formation of lower Ganchaigou formation (?) and upper Ganchaigou formation (Nj) has the character of large thickness and distributional stability, which is the regional cap formation in north rim of Chaidamu basin. There are fine local cap formations existing in upper and lower Youshashan formation of Jurassic system.There are four kinds of fault, according to geometric character of fault, which are deep-seated fault, the fault surface cross cap formations but is not reach to ground, the fault surface cross to ground and ground fault. Discuss the closure ability, based on the active stage and the lithlogic of two sides in fault.Divid sixteen belts in north rim of Chaidamu basin, based on the migration, accumulation, conservation conditions of petroleum and incorporated with framework of structure, combination of reservoir formation. And perform the study of geological evaluation, resource potential analysis, economic and technique evaluation. Then select 5 favorable areas.