摘要
南襄盆地南阳凹陷烃源岩干酪根类型以Ⅱ1-Ⅱ2型为主,核桃园组二段二亚段与核桃园组二段三亚段有机质类型好于核桃园组三段。核桃园组二段以细菌和低等植物来源为主,核桃园组三段的植物来源更丰富。有机质丰度以核桃园组二段三亚段最高,其次是核桃园组三段一亚段,核桃园组三段二亚段与核桃园组二段二亚段相当,达到了中等烃源岩条件,核桃园组二段一亚段最差。南阳凹陷有效烃源岩分布面积自下而上逐渐变小,烃源岩分布逐渐向南部深洼带收缩和集中。资源重新复算表明:该区资源量由0.62×108t增加到1.04×108t。核桃园组三段二亚段占该区资源量的37.5%,其次是核桃园组三段一亚段、核桃园组二段三亚段及核桃园组二段二亚段。整个核桃园组三段占该区总资源量的59.6%。说明核桃园组三段是南阳凹陷的主力烃源层,因其目前资源探明率低,应还有较大的勘探潜力,这为该区加快深层的勘探提供了依据。
Kerogens of source rocks in the Nanyang depression of Nanxiang Basin are dominated by type Ⅱ 1 and type Ⅱ 2, and the organic types of the middle and lower Member Ⅱ of Hetaoyuan Formation (HF) are better than that of the Member Ⅲ of HF. The organic matters of the Member Ⅱ of HF are mainly sourced from bacteria and lower plants, while that of the Member Ⅲ of HF from plants. The organic matter abundance of the source rocks of HF are different for different sub-members. The richest one is the lower Member Ⅱ , followed by the upper Mem- ber m. The organic matter abundance of the middle Member m is moderate just like the middle Member Ⅲ. The upper Member Ⅱ is the lowest. The distribution area of active source rocks gradually becomes smaller upwards, and the source rocks concentrated in deep depression to the south. The resources in place by this reassessment are 104 million tons, much larger than 62 million tons by the last assessment. The resources of the middle Mem- ber Ⅲ are the largest, accounting for 37.5 % of the total resources, followed by the upper Member m, the lower and middle Member Ⅱ. The resources of the Member Ⅲ account for 59.6 % of the total resources, indicating that the Member m is the main source rocks of the Nanyang depression. However, the resource exploration ma- turity for the depression is quite low, indicating that the exploration potential for the depression may be large.
出处
《石油与天然气地质》
EI
CAS
CSCD
北大核心
2012年第3期392-398,共7页
Oil & Gas Geology
关键词
烃源岩
地质资源量
核桃园组
南阳凹陷
南襄盆地
source rock, resource in place, Hetaoyuan Formation, Nanyang depression, Nanxiang Basin