第四纪沉积物天然热释光测量方法技术研究——山东草桥油田研究实例

第四纪沉积物天然热释光测量是一种累积间接油气勘查新方法。文中给出了首次系统研究的成果 ,从数百个样品中总结出的适用油气勘探的预热线形升温、恒温最佳加热程序 ,升温速率以 β=6℃ /s为宜 ,恒温温度 40 0℃ ,40 0℃恒温时间为 12s。在沉积物辐射剂量响应及日光晒退实验数据的基础上 ,总结了样品采集、预处理及测量方法。通过对山东草桥油田第四纪沉积物天然热释光与游离气烃野外实测资料的分析 ,发现天然热释光异常与气烃异常完全吻合 ,在油水边界上方 ,热释光、甲烷、乙烷出现高值异常 ,油田上方是低值带 ,为串珠状异常模式。热释光最大值为 2 0 4.2 μGy ,平均值为 79.45μGy ,标准差为 3 4 .14 μGy ;甲烷浓度异常下限为 2 5μL/L ,乙烷浓度异常下限为 4.4μL/L。

MEASUREMENT TECHNIQUE OF NATURAL THERMOLU- MINESCENCE OF QUATERNARY SEDIMENT AND ITS APPLICATION TO PROSPECTING OF HYDROCARBON RESERVOIRS IN CAOQIAO OILFIELD, SHANDONG PROVINCE, EAST CHINA

The measurement of natural thermoluminescence of Quaternary sediment is a new method for oil and gas prospecting. Based on glow\|curves of hundreds of samples we present an optimum heating up program for thermoluminescence read out. We have also summarized the methods for sampling, pretreatment and measurement of natural thermoluminescence from the data of thermoluminescence response to the radiation and of the remaining after “bleaching” due to exposure to sunlight. The application of the method to Caoqiao oil field in Shandong Province shows that the anomalies of thermoluminescence coincide well with methane and ethane anomalies. There are closed maximum of thermoluminescence, methane and ethane anomalies over the boundary between oil and water, and closed minimum with pinch\|and\|swell form over the hydrocarbon reservoir. The maximum of thermoluminescence is 204.2 μGy, the average is 79.45 μGy, and the standard error is 34.14 μGy. The threshold of methane and ethane are 25 μL/L and 4.4 μL/L, respectively.