澳大利亚西北陆架油气成藏主控因素与勘探方向

以澳大利亚西北陆架勘探现状和油气田最新资料为基础,采用油气地质综合分析方法,探讨油气成藏主控因素与有利勘探方向。研究结果表明:成藏主控因素为源盖控区,大型浪控海相三角洲控藏。北卡那封(North Carnavon)盆地发育滦金(Rakin)台地与埃克斯茅斯(Exmauth)台地两大有利区和古新统海相浊积砂岩潜在油气富集体。波拿巴(Bonaparte)盆地已有巨型油气田中发现的萨胡尔(Sahul)台地、武尔坎(Vulean)次盆和玛丽塔(Malita)地堑等较成熟探区再有重大发现的潜力仍然巨大,上白垩统Puffin组水下扇和斜坡扇浊积砂岩与阿什莫尔(Ashmon)台地中新统生物礁是该盆地两大新领域。布劳斯(Browse)盆地存在围绕盆地富烃凹陷卡斯威尔(Caswell)次盆分布的4大油气富集有利构造带和Puffin组浊积砂岩潜在有利勘探目标层位。柔布克(Roebuck)盆地勘探程度极低,各成藏条件有待于厘定。

Main controlling factors for hydrocarbon accumulation in north west shelf of Australia and its favorable exploration direction

Based on the current exploration situation and latest database of fields,by applying analysis of hydrocarbon geology,main controlling factors for hydrocarbon accumulation north west shelf of Australia and its favorable exploration direction are analyzed.The results show that the main control factors of hydrocarbon accumulation are coupling of source and seal control hydrocarbon distribution area,large wave dominated deltas dominate accumulation zone.Two large profitable areas,Rankin platform and Exmouth platform,and Palaeocene marine turbidite sandstone exist in North Carnarvon basin.Sub-mature exploration areas in Bonaparte basin,like Sahul platform,Vulcan subbasin,and Malita graben have great potential of hydrocarbon rediscovery.Two new fields exist in Bonaparte basin,one is Upper Cretaceous Puffin formation subsea apron and slope fan turbidite sandstone,and the other is Miocene patch reef at Ashmore platform.In Browse basin,there are four hydrocarbon profitable structural zones surrounding hydrocarbon-rich depression of Caswell subbasin and Puffin formation turbidite sandstone,which is potential profitable exploration target.The degree of exploration is extremely low in Roebuck basin,and every hydrocarbon accumulation condition needs to be confirmed.