澳大利亚西北陆架波拿巴盆地油气资源潜力评价

Bonaparte basin petroleum resource assessment,northwest shelf of Australia

波拿巴盆地是澳大利亚主要含油气盆地之一,也是我国石油公司海外油气勘探涉足的重点区。通过深入分析盆地油气地质特征,认为该盆地主要发育中生界含油气系统,油气分布呈现东部富气、西部油气并存的特点。通过分析盆地东、西部在构造样式、烃源岩成熟度、圈闭形成背景和保存条件等方面的差异,将该盆地中生界成藏组合在平面上划分为乌尔坎和马里塔2个评价单元,并以勘探趋势法和分段式油藏规模序列法为手段确定评价参数,采用蒙特卡洛法预测该盆地的石油、凝析油和天然气待发现可采资源量分别为934 MMb(1.48×10~8 m^3)、1 909 MMb(3.04×10~8 m^3)、34 387 Bcf(9 737.3×10~8 m^3)。综合分析认为,该盆地具有很高的勘探潜力,马里塔坳陷是下一步寻找大中型气田的有利勘探区。

Bonaparte basin is one of the major oil and gas-bearing basin in Australia,and it is also an important area for China oil company exploration.According to the detailed petroleum geology analysis of Bonaparte basin,the Mesozoic is considered as a major petroleum system.Gas mainly distributes in the eastern part,and oil and gas coexist in the western part.By analyzing the difference of structure style,source rock maturity,trap deformation setting and preservation between the eastern and western parts,Mesozoic play is divided into two parts as Vulcan assessment unit and Malita assessment unit.The assessment parameters are determined by exploration trend and reservoir size sequence method.The forecasted undiscovered recoverable resources of the two assessment units are 1.48×10~8 m^3 oil,3.04×10~8 m^3 condensate and 9 737.3×10~8 m^3 gas with Monte Carlo method.Based on comprehensive analysis,Bonaparte basin has great exploration potential and Malita graben is the favorable exploration area for large-middle gas fields in future.