【摘要】 波拿巴盆地油气资源十分丰富。新生界千余米的浅海碳酸盐岩背景下,中新统底部发育一套12~52 m硅质碎屑与碳酸盐混合沉积,其中硅质碎屑作为潜在的良好储集体,尚未引起足够重视。综合运用录井、测井及三维地震等资料,认为盆地北部研究区内该套混合沉积是由陆棚浅海台地生物滩、坝碳酸盐和三角洲平原和前缘硅质碎屑混合而成,以相在空间上的交叉占优势。该套混合沉积主要受到构造运动和相对海平面变化控制。在渐新世末期,盆地发生区域构造抬升,古隆起接受剥蚀,陆源碎屑进入台地,是形成这套混合沉积的先决条件,之后中新世初期构造相对稳定,相对海平面在短时间内的周期性变化控制陆源碎屑沉积范围和碳酸盐生产建造,进而控制混和沉积作用的类型。更多还原

【Abstract】 The Bonaparte Basin is rich in oil and gas resources.There occur more than one thousand meters of Cenozoic shallow marine carbonate deposits.At the bottom of the Miocene,there is a mixed sequence of siliciclastic and carbonate sediments up to 12~52 m thick.The terrigenous siliciclastics in the mixed sequence,however,have not been carefully studied so far as a potential reservoir by researchers.Based on the logging and 3D seismic data,the authors found that the alternation of terrigenous siliciclastic delta facies and shelf-derived carbonate platform facies in space is commonly seen in the northern Bonaparte Basin.The deposition of the mixed sediments depends upon regional tectonics and relative sea level changes.In the late Oligocene,regional tectonic uplifting caused erosion of the source area.A great amount of terrigenous siliciclastics were brought into the basin which was dominated by the deposition of carbonate platforms.In the early stage of the Miocene,when the region was tectonically stabilized again,short-term relative sea level changes played significant roles in the formation of the mixed sediments through affecting the re-distribution of terrigenous and the production of carbonate sediments.更多还原