苏北盆地金湖凹陷热史与成藏期判识
- 收稿日期:
1900-01-01
- 修回日期:
1900-01-01
- 刊出日期:
2011-04-10
摘要: 在镜质体反射率和磷灰石裂变径迹系统测试分析的基础上，对金湖凹陷西斜坡和卞闵杨构造带进行古地温梯度计算和热史恢复。根据镜质体反射率计算出西斜坡的古地温范围介于45.6～128.4℃，古地温梯度为45.5℃/km；卞闵杨构造带古地温为26.4～120.3℃，古地温梯度为42.7℃/km。根据磷灰石裂变径迹计算出西斜坡古地温梯度为40.7℃/km，卞闵杨构造带为45.8℃/km。对比分析得出凹陷内不同构造带均具有古地温梯度大于今地温梯度的规律，西斜坡古地温梯度高于现今10.4～15.2℃/km，卞闵杨构造带古地温梯度高于现今12.4～15.3℃/km。对西斜坡和卞闵杨构造带典型井进行热史模拟，得出古地温梯度随着凹陷地层年代变新而降低，三垛构造事件所导致的抬升剥蚀之前，凹陷已达到最大古地温。成熟度史反映出金湖凹陷埋深在1 000 m处Ro为0.4%，烃源岩进入低熟阶段，在1 900 m处Ro为0.65%，温度达到90℃，烃源岩进入生烃高峰阶段。将金湖凹陷西斜坡典型单井埋藏史—热史与包裹体均一温度综合分析，判识出成藏期介于47～41.5 Ma，确定了三垛期为金湖凹陷主成藏期。
Thermal History Reconstruction and Hydrocarbon Accumulation Period Discrimination of Jinhu Depression in Subei Basin
- Research Center of Basin & Reservoir,China University of Petroleum, Beijing 102249
- Received Date:
1900-01-01
- Rev Recd Date:
1900-01-01
- Publish Date:
2011-04-10
Abstract: Based on the analysis of the vitrinite reflectance and apatite fission track inclusions system testing, we carried out the calculation of paleotemperature gradient and reconstruction of thermal history , and then identified the paleotemperature gradient of west slope and Bianminyang tectonic zone of Jinhu depression. According to the vitrinite reflectance, we calculated that the range of the paleotemperature being between 45.6~128.4℃ and the paleotemperature gradient was
45.5 ℃/km in the west slope, the paleotemperature in Bianminyang tectonic zone was 26.4~120.3℃ and the paleotemperature gradient was 42.7℃/km. According to the apatite fission track, we calculated that the paleotemperature gradient in the west slope was 40.7℃/km, and in Bianminyang tectonic zone was 45.8℃/km. From the comparative analysis with different tectonic zones of Jinhu depression, we concluded a law that the paleo temperature gradient was higher than presentday geothermal gradient, specifically as follows: in the west slope, paleotemperature was 10.4~15.2℃/km higher than the current, and in Bianminyang tectonic zone paleotemperature was 12.4~15.3℃/km higher than the present.By the thermal history modeling of typical wells in west slope and Bianminyang tectonic zone, it could be seen that the paleogeothermal gradient became lower with the stratigraphical time changed for the new. It shows that the geothermal gradient of K2t~E1f was higher than E2d~Ny. Before the uplift and erosion caused by the Sanduo tectonic events, the paleotemperature of depression had reached the maximum. The maturity history of depression reflected that the Ro was 0.4% in the depth of 1 000 m of Jinhu depression. The source rock was at the lowmature stage.The Ro was 0.65% in the depth of 1 900 m and the temperature reached 90℃, the hydrocarbon source rocks entered the peak phase. The homogenization temperature of fluid inclusion samples was between 62~93℃ of Well Cui 2 in the west slope. Through the comprehensive analysis of the burial historythermal history of typical singlewell and the homogenization temperature of fluid inclusions, it can be identified that the accumulation period of Jinhu depression was between 47~41.5 Ma.Then it could be judged that the Sanduo period(E2s)was the main hydrocarbon accumulation period of Jinhu depression.
李亚军. 苏北盆地金湖凹陷热史与成藏期判识[J]. 沉积学报, 2011, 29(2): 395-401.
| 引用本文: |
李亚军. 苏北盆地金湖凹陷热史与成藏期判识[J]. 沉积学报, 2011, 29(2): 395-401.
|
LI Yajun. Thermal History Reconstruction and Hydrocarbon Accumulation Period Discrimination of Jinhu Depression in Subei Basin[J]. Acta Sedimentologica Sinica, 2011, 29(2): 395-401.
| Citation: |
LI Yajun. Thermal History Reconstruction and Hydrocarbon Accumulation Period Discrimination of Jinhu Depression in Subei Basin[J]. Acta Sedimentologica Sinica, 2011, 29(2): 395-401.
|
点击查看大图
下载:
