利用微差井温确定原始地层的导热系数

Determination of thermal conductive factor of original formation through microdifference temperature.

利用微差井温确定原始地层的导热系数，基于能量守衡（地热流密度相等）这一原理。在合理假设平板状地层、无奇点热源或热汇，忽略放射性产生的热量，井筒内无宏观流体流动、完井时间足够长等条件的基础上，建立了数学方程；在对油田内井下测温设备调研的基础上，对测试过程进行误差分析后，筛选到了合适的测温设备；在对钻井工艺，测井工艺充分了解的基础上，利用完井报告，设计并完成了四口井的测试工作并进行了解释。同时，还对完井后温度恢复程度、井筒存在套管、水泥环、井液对此种方法的影响进行了分析研究。

The principle of determining thermal conductive factor of original formation through microdifference temperature is conservation of energy(equal density of geothermal heat flow). Mathematical equation is established based on the conditions of reasonable assuming tabular formation, no singular points of heat source or heat confluence, neglecting of heat generated by radioactivity, no macro fluid flow in well bore, and sufficient time after well completion; according to evaluation for temperature log equipments, after error analysis of testing process, a suitable temperature testing equipment is screened; based on fully understanding of drilling and logging technologies, making use of final well report, tests for four wells are designed and finished, and the interpretation of data of the tests is also given.Whereas,studies on effects of temperature restoring degree after completion, influence of casing, cement sheath and well fluid on this method are carried out.