IODP349航次地热调查数据分析  

Geothermal data processing and analysis for IODP Expedition 349

作　　者：张文涛 许鹤华[1] 杨小秋[1] ZHANG Wentao;XU Hehua;YANG Xiaoqiu(Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301 , China;University of Chinese Academy of Sciences, Beijing 100049, China)

机构地区：[1]中国科学院边缘海与大洋地质重点实验室中国科学院南海海洋研究所,广州510301 [2]中国科学院大学,北京100049

出　　处：《海洋地质与第四纪地质》2018年第2期156-164,共9页Marine Geology & Quaternary Geology

基　　金：中国科学院战略性先导科技专项(A类)(XDA13010303);国家自然科学基金(41376061;91428205)

摘　　要：海底热流是研究大洋地壳和上地幔岩石圈热状态的重要参数。为了解南海深水区地热特征,利用IODP349航次地热调查资料进行数据处理,得到了4个站位浅层热导率数据和3个钻孔的海底热流数据。结果表明,浅层沉积物样品热导率变化范围为0.8~2.2 W/(m·K),变化范围与沉积物成分有关,热导率随深度的增加有小幅增加的趋势与沉积物压实作用有关;U1431D、U1432C和U1433A三个钻孔热流值分别为24±8mW/m2、105±3mW/m2和89±2mW/m2,后两个钻孔通过与前人实测数据进行对比,与前人结果相当,表明了结果的可靠性;U1431D发生地温梯度倒转和低热流异常可能是与钻孔处于水热循环的下降流附近有关。The seafloor heat flow,as an effective parameter to the study of thermal state,is an important indicator of the oceanic crust or upper crustal lithosphere.To understand the geothermal distribution pattern of the deepwater areas of the South China Sea,the geothermal data of IODP Expedition 349 is processed and studied.We acquired shallow thermal conductivities at four sites and seafloor heat flow data at three sites.The results show that the thermal conductivity varies in a range of 0.8 - 2.2 W/（m·K）,which depends upon the composition of sediments.The thermal conductivity of the sediments increases slightly with depth,probably owing to the effect of sediment compaction.The heat flow of Hole U1431 D,Hole U1432 C and Hole U1433 A is 24±8 mW/m^2,105±3 mW/m^2 and 89±2 mW/m^2 respectively,basically consistent with previous results and the data from the nearby area.It proves that our results are reliable.The reverse of geothermal gradient and the low heat flow at Site U1431 might be caused by a downwell limb of hydro-thermal circulation.

关 键 词：海底热流 IODP349 数据处理与分析 热导率 热流异常 

分 类 号：P744[天文地球—海洋科学]