东营凹陷现代热流场特征及地热异常成因

Determination and interpretation of the terrestrial heat flow in Dongying depression.

大地热流是表达地球表面向外界空间散发热量的重要物理量，其大小与岩石圈结构和区域构造演化过程相关。建立了东营凹陷地热场计算的简化模型，利用热导率分散模型计算了自明化镇组至沙四段上部的原地热导率；在此基础上，利用热阻率法，根据１７０ 口测温井的测温资料，计算这些井点处的大地热流值，结果是：东营凹陷现代大地热流值为３０ ～１２０ｍＷ／（ｍ·Ｋ） ，平均值为６８ ｍ Ｗ／（ｍ·Ｋ） 。认为控制东营凹陷大地热流值异常的主要因素是：①新生代火山活动的影响；②第三系沉积岩的有效热导率平面分布有变化；③人文活动（ 如钻探、注水采油等） 的影响。

Heat flow density is an important parameter to indicate the capacity of Earth to give out thermal energy, but it is difficult to be measured directly. In this paper, the sedimentary model is simplified in Dongying depression, and the dispersive model method of thermal sedimentary rock conductivity is used to computed the in situ thermal conductivity of the Tertiary sedimentary strata in turn in Dongying depression, on the base of the results and the temperatures measured in 170 wells, thermal resistance method is used to compute the present heat flow at the sites of these temperature measured wells. The heat flow densities in Dongying depression range between 30 120mW/m·K, with an average value of 68mW/m·K. The distribution of heat flow density in the depression is closely related to factors, which are enumerated in the most likely order of importance: ①the Cenozoic volcanic activities in Dongying depression; ②the effective in situ thermal conductivity pattern in the depression; ③artificial activities, such as drill hole exploration, water injection and oil mining.