地质学报2017，Vol.91Issue(8)：1720-1728,9.
南海北康盆地热流分布特征及其构造控制因素探讨
Heat Flow Characteristics and Controlling Factors of the Baikang Basin in South China Sea
摘要
Abstract
Heat flow is the basis data for gas hydrate reserves estimation and the oil and gas resource evaluation.The existing heat flow data measured in the South China Sea are huge but the data distribution is uneven.In order to understand the geothermal feature of the Beikang basin,this study mapped the distribution of hot flow in the Beikang basin using the measured heat flow data and previous research results.According to the characteristics of heat flow and geothermal gradient,the formation mechanism of heat flow anomaly zone in the northwest of the basin was discussed.The regional geology structure was used to analyze the characteristics of heat flow and geothermal gradient of Beikang basin and their main influence factors.The main controlling factors of heat flow distribution were briefly analyzed with the regional geological tectonic background.Statistics results show that:Heat flow varies from 43.0 to 115.0 mW/m2 with an average value of 76.8±21.7 mW/m2,meanwhile the geothermal gradient ranges from 49.0 to 133.1 ℃/km with the mean of 82.2±22.4 ℃/km.Heat flow is generally high,characterized by higher in the south and west than in the east,with the lowest in the southeast.And there is distinct heat flow anomalous zone in the northwestern basin.Further analysis shows:(1) Heat flow anomaly in district B is mainly influenced by the burial depth and/or thickness of high conductive layers in the crust,and districts A and C are caused by the hydrothermal circulation of seafloor fluid-seep system.It can be inferred that district A should be recharge area and district C be the discharge area;(2) Heat flow distribution of the basin is obviously controlled by tectonic,with northwest and south controlled by Tinjar fault and southeast by continentocean boundary and ancient subduction zone.The distribution feature high in west and low in east was likely related to three rapid sedimentation events,but the regional high heat flow is due to the stretching of the basin.It is of great significance to the research of hydrocarbon and gas hydrate.关键词
北康盆地/海底热流/地温梯度/流体渗漏区/拉张/南海Key words
Beikang basin/seafloor heat flow/geothermal gradient/fluid-seep area/stretching/South China Sea引用本文复制引用
陈爱华,徐行,罗贤虎,廖开训,彭登..南海北康盆地热流分布特征及其构造控制因素探讨[J].地质学报,2017,91(8):1720-1728,9.基金项目
本文为国土资源部海底矿产资源重点实验室开放基金(NO.KLMMR-2014-A-05)、国家重大项目配套科研(GZH201500508)、国家自然科学基金重大研究计划(NO.91428205)、国家863计划科研项目(2006AA09A203)资助的成果. （NO.KLMMR-2014-A-05）
