南海东部油气勘探失利原因分析

Causes analysis of unsuccessful exploration in eastern South China Sea

在分析南海东部海域钻探失利井基础上,重点研究了油气运移对油气成藏的控制作用,认为研究区勘探存在4种不利因素:钻探目标背离构造脊、构造脊断裂散失、缺乏沟通油源断层、疏导层倒转。PY66翘倾半背斜构造钻探失利的原因是构造脊雁行式断裂造成油气层层爬升漏失,LF141构造钻探失利主要原因是原油没有跨越断层逆向运移。通过分析认识到,油气运移是油气成藏的主控因素。通过研究探区的油气运移规律,勘探获得了成功,也为今后勘探明确了方向。

Based on the analysis of unsuccessful drilling in the eastern South China Sea, this paper mainly studies the control effect of oil and gas migration on oil and gas accumulation. It is considered that there are at least four kinds of drilling unsuccessful factors caused by oil and gas migration in this area, such as the drilling target deviating from the structure crest, losing structure crest, lacking source-related faults and leading bed reversal. For example, the drilling of PY66 tilting half anticline can not get the commercial discovery, the reason is structural ridge line fault caused the oil and gas lost when climbing. The reason of drilling failure for LFI41 structe is crude oil needed to go cross the fault to make the reverse migration. Through the analysis, it is recognized that the migration of oil amt gas is the main controlling factor in oil and gas accumulation. Through strengthening the research, the successfiil explorations are gotten, which can clear the direction in future exploration.