Regional overview of deep sedimentary thermal gradients of the geopressured zone of the Texas–Louisiana continental shelf
Regional overview of deep sedimentary thermal gradients of the geopressured zone of the Texas–Louisiana continental shelf
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DOI：
10.1306/08070706111
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发表时间：
2008
期刊：
影响因子：
3.5
通讯作者：
S. Nagihara;M. Smith
中科院分区：
文献类型：
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作者：
S. Nagihara;M. Smith
墨西哥湾北方大陆架近600个井底温度数据，每个数据都经过钻井干扰校正，产生了一个大约6公里（3.7英里）的海底地热梯度区域图。在地图上可以看到两个地理趋势。首先，从东到西，地温梯度在0.025 ~ 0.03 K/m之间变化（0.014和0.016°F/ft）至0.015-0.025 K/m的较低值路易斯安那州东部近海的最高温度为0.008-0.014°F/ft，路易斯安那州西部近海通过德克萨斯州的最高温度为0.03-0.06 K/m。第二，朝向外大陆架的温度梯度往往较低（低于0.02 K/m [0.0112°F/ft]）。我们认为，所观察到的变化主要是由于在新生代的快速和区域性变化的沉积物积累，这导致在德克萨斯州-路易斯安那州的货架上的超高压区的发生的热效应。在路易斯安那州东部大陆架，那里的沉积最快，沉积物下降到约6公里（3.7英里）是相对年轻的（约
Nearly 600 bottom-hole temperature data from the northern continental shelf of the Gulf of Mexico, each corrected for drilling disturbance, yielded a regional map of geothermal gradient down to approximately 6 km (3.7 mi) sub–sea floor. Two geographic trends can be seen on the map. First, from east to west, the geothermal gradient changes from values between 0.025 and 0.03 K/m (0.014 and 0.016°F/ft) off the Alabama–Mississippi shore to lower values of 0.015–0.025 K/m (0.008–0.014°F/ft) off eastern Louisiana and to higher values of 0.03–0.06 K/m (0.016–0.033°F/ft) off western Louisiana through Texas. Second, thermal gradients tend to be lower toward the outer continental shelf (less than 0.02 K/m [0.0112°F/ft]). We believe that the observed variations are primarily attributable to the thermal effect of rapid and regionally variable sediment accumulation during the Cenozoic era, which resulted in the occurrence of the geopressured zone in the Texas–Louisiana shelf. In the eastern Louisiana shelf, where accumulation was fastest, sediments down to about 6 km (3.7 mi) are relatively young (about