摘要
沁水盆地是华北克拉通内的构造盆地，是天然气勘探的潜在重要区域，盆地的热史研究是天然气储层评价的重要基础。重点应用磷灰石裂变径迹的分析与模拟，配合镜质体反射率的分析与模拟以及区域构造地质背景分析，恢复了沁水盆地的古地温梯度和地热演化模型：早古生代地温梯度稳定，为3℃／100m，晚二叠世至三叠纪地温梯度较前期略有降低，约为2．5～3．0℃／100m；早、中侏罗世地温梯度开始上升，约为3．0～4．0℃／100m；晚侏罗世-早白垩世地温梯度大幅度上升，为4．5～6．5℃／100m；晚白垩世至古近纪早、中期为高地温场的延续时期，地温梯度为5．5～6．5℃／100m；古近纪晚期-新近纪早期地温梯度大幅度降低，从6．0℃／100m骤降至4．2℃／100m左右；中新世以来地温场逐渐趋于稳定，地温梯度由4℃／100m演变到接近现代地温场的3℃／100m左右。
The Qinshui Basin within the North China Craton is a potential area for natural gas exploration, and thus the thermal history is a key to evaluate the reservation of the natural gas in this basin. Using apatite fission track and vitrinite reflection modelling techniques, the thermal history of the Qinshui Basin in Shanxi Province was modelled. The temperature gradients of the Qinshui Basin changed with geological stages： 3 ℃/100 m at Early Palaeozoic, 2. 5 -3.0℃/100 m from Late Permian through Triassic, 3.0 -4. 0℃/100 m at Early-Mid- dle Jurassic, 4. 5 -6.5 ℃/100 m at Late Jurassic-Early Cretaceous, 5.5 -6. 5 ℃/100 m at Late Cretaceous to Palaeogene, 6. 0 ℃/100 m at Late Palaeogene and 4.2℃/100 m at Early Neogene. Since Miocene to the present, the temperature gradient kept relatively stable at 3 ℃/100 m.
出处
《现代地质》
CAS
CSCD
北大核心
2009年第6期1093-1099,共7页
Geoscience
关键词
沁水盆地
裂变径迹
镜质体反射率
古地温梯度
山西
Qinshui Basin
apatite fission track
vitrinite reflectance
palaeo-temperature gradient
Shanxi
