南海西南次海盆的地热流特征与分析
|
摘要
为系统地了解南海西南次海盆的地热流特征,本文通过对研究区及邻域地热流数据的补充采集、收集整理和统计分析,获得了87个有效的地热流数据、一批热导率和生热率的地热参数资料,地热流测点在空间上覆盖了整个区域.研究区的地热流数据分布结果表明,西南次海盆热流密度的平均值为98.1±14.8mW·m~(-2),洋陆过渡带为103.6±19.4mW·m~(-2),南沙岛礁区和西部陆缘分别为79.0±15.5mW·m~(-2)和78.3±15.6mW·m~(-2).研究区表层沉积物热导率的平均值0.86±0.06 W·mK~(-1),生热率的平均值1.11±0.17μW·m~(-3),海底温度的平均值为2.43±0.01℃.综合海底地形地貌、地质与地球物理资料,认为研究区的热流特征在空间上具有一定的分布规律,表现为:(1)洋盆区测点的热流密度平均值高于两侧陆缘;(2)东南缘洋陆过渡带上测点的地热流密度值高于邻近海盆和南沙岛礁区的测点,而西北缘这种特征不明显;(3)西北翼的热流密度值总体比东南翼高;(4)沿着古扩张中心方向,西南次海盆热流值具有自东北向西南端方向逐步增大的趋势,表明海盆区同时存在着洋中脊与大陆裂谷两种不同的热状态,西南段裂谷热流值比东北段洋中脊高.对西南次海盆沉积物的热导率和生热率值参数的测量及数据空间分析可见,这两种热参数的空间分布无明显规律性,可能与海盆形成之后复杂的沉积环境相关.根据热流-洋壳年龄之间的关系,在西南次海盆东北段26个测站数据中,发现靠近古扩张中心的数据与理论值呈负偏移,而远离古扩张中心的数据呈正偏移,此现象是海盆内地热流数据受不同类型的地下流体影响所致.
To have a better understanding of the heat flow characteristics in the Southwest subbasin of South China Sea(SWSB),we have acquired and re-collected 87 sets of valid heat flow data and multiple kinds of geothermal parameters data,including thermal conductivity and heat generation rate.The heat flow sites could cover whole study area in space.The distribution of heat flow shows that the average values of heat flow in oceanic basin is 98.1±14.8 mW·m~(-2).Besides,it is 103.6±19.4 mW·m~(-2) in continent-ocean transition zone while 79.0±15.5 mW·m~(-2) and 78.3±15.6 mW·m~(-2) in Nansha and west margin of SWSB respectively.The average values of thermal conductivity and heat generation rate in surface sediment are 0.86±0.06 W·mK~(-1) and 1.11±0.17μW·m~(-3) respectively.The mean seafloor temperature is 2.43±0.01 ℃.Combined with the newest geomorphology of SWSB and its geological-geophysical data,it is learned that the distribution of heat flow is under certain regularity as follows.(1)The average value of heat flow in oceanic basin is higher than continental margins.(2)The heat flow in the continental-ocean transition zone of southeastern margin is higher than adjacent oceanic basin and Nansha area.Differing from the southeastern margin,this situation in northwestern margin is not obvious.(3)The heat flow in northwestern margin is generally higher than southwestern margin of SWSB.(4)Along the direction of ancient residual spreading ridge center,the heat flow have the tendency of increase from the northeastern toward southwestern side.It shows that there are two different thermal characteristics of mid-ocean ridge and rifted continent in SWSB.The heat flow of rifted continental in southwestern side is higher than mid-ocean ridge in northwestern side.By analyzing and studying the spatial distribution of measured sediment thermal conductivity and heat generation rate,it indicates that the distribution of these two kinds of thermal parameters has no obvious regularity.It may be associated with the complex depositional environment after basin formed.According to the relationship of heat flow and oceanic age,it is found that the heat flow in the southwestern oceanic basin is lower than theoretical value when the sites are close to the residual spreading ridge and higher than theoretical value when the sites are far from the residual spreading ridge.These results imply that the heat flow in oceanic basin is affected by different types of underground fluid.
To have a better understanding of the heat flow characteristics in the Southwest subbasin of South China Sea(SWSB),we have acquired and re-collected 87 sets of valid heat flow data and multiple kinds of geothermal parameters data,including thermal conductivity and heat generation rate.The heat flow sites could cover whole study area in space.The distribution of heat flow shows that the average values of heat flow in oceanic basin is 98.1±14.8 mW·m~(-2).Besides,it is 103.6±19.4 mW·m~(-2) in continent-ocean transition zone while 79.0±15.5 mW·m~(-2) and 78.3±15.6 mW·m~(-2) in Nansha and west margin of SWSB respectively.The average values of thermal conductivity and heat generation rate in surface sediment are 0.86±0.06 W·mK~(-1) and 1.11±0.17μW·m~(-3) respectively.The mean seafloor temperature is 2.43±0.01 ℃.Combined with the newest geomorphology of SWSB and its geological-geophysical data,it is learned that the distribution of heat flow is under certain regularity as follows.(1)The average value of heat flow in oceanic basin is higher than continental margins.(2)The heat flow in the continental-ocean transition zone of southeastern margin is higher than adjacent oceanic basin and Nansha area.Differing from the southeastern margin,this situation in northwestern margin is not obvious.(3)The heat flow in northwestern margin is generally higher than southwestern margin of SWSB.(4)Along the direction of ancient residual spreading ridge center,the heat flow have the tendency of increase from the northeastern toward southwestern side.It shows that there are two different thermal characteristics of mid-ocean ridge and rifted continent in SWSB.The heat flow of rifted continental in southwestern side is higher than mid-ocean ridge in northwestern side.By analyzing and studying the spatial distribution of measured sediment thermal conductivity and heat generation rate,it indicates that the distribution of these two kinds of thermal parameters has no obvious regularity.It may be associated with the complex depositional environment after basin formed.According to the relationship of heat flow and oceanic age,it is found that the heat flow in the southwestern oceanic basin is lower than theoretical value when the sites are close to the residual spreading ridge and higher than theoretical value when the sites are far from the residual spreading ridge.These results imply that the heat flow in oceanic basin is affected by different types of underground fluid.
引文
Anderson R N,Langseth M G,Hayes D E,et al.1978.Heat flow,thermal conductivity,thermal gradient.∥Hayes D Eed.Geophysical Atlas of the East and Southeast Asian Seas,Map and Charts Series.Boulder,CO,USA:Geological Society of American,125.
Briais A,Tapponnier P,Pautot G.1989.Constraints of Sea beam data on crustal fabrics and seafloor spreading in the South China Sea.Earth and Planetary Science Letters,95(3-4):307-320.
Briais A,Patriat P,Tapponnier P.1993.Updated interpretation of magnetic anomalies and seafloor spreading stages in the South China Sea:Implications for the tertiary tectonics of Southeast Asia.Journal of Geophysical Research:Solid Earth,98(B4):6299-6328.
Hyndman R D,Erickson A J,VonHerzen R P.1974.Geothermal measurement on DSDP Leg 26.∥Davies T A,Luyendyk B Peds.Initial Reports of the Deep Sea Drilling Project 26.Washington:US Government Printing Office,675-742.
Li C F,Xu X,Lin J,et al.2014.Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP expedition 349.Geochemistry,Geophysics,Geosystems,15(12):4958-4983.
Li C F,Lin J,Kulhanek D K,et al.2015.Proceedings of the international ocean discovery program,349:South China Sea tectonics.San Diego,CA:IODP,doi:10.14379/iodp.proc.349.105.2015.
Li J B,Ding W W,Gao J Y,et al.2011.Cenozoic evolution model of the sea-floor spreading in South China Sea:New constraints from high resolution geophysical data.Chinese Journal of Geophysics(in Chinese),54(12):3004-3015,doi:10.3969/j.issn.0001-5733.2011.12.003.
Li S Z,Guo X Y,Hou F H,et al.2004.Segmentation,propagation and overlapping at mid-oceanic ridge.Marine Geology Letters,20(11):19-28.
Li X B,Wu Z L,Li J B.2013.The preliminary study of segmentation of the mid-ocean ridge in southwest sub-basin of the south china sea.Marine Geology&Quaternary Geology(in Chinese),33(3):101-107.
Li Y M,Luo X H,Xu X,et al.2010.Seafloor in-situ heat flow measurements in the deep-water area of the northern slope,South China Sea.Chinese Journal of Geophysics(in Chinese),53(9):2161-2170,doi:10.3969/j.issn.0001-5733.2010.09.016.
Mi L J,Yuan Y S,Zhang G C,et al.2009.Characteristics and genesis of geothermal field in deep-water area of the northern South China Sea.Acta Petrolei Sinica(in Chinese),30(1):27-32.
Nissen S S,Hayes D E,Yao B C,et al.1995.Gravity,heat flow,and seismic constraints on the processes of crustal extension:Northern margin of the South China Sea.Journal of Geophysical Research:Solid Earth,100(B11):22447-22483.
Parsons B,Sclater J G.1977.An analysis of the variation of ocean floor bathymetry and heat flow with age.Journal of Geophysical Research,82(5):803-827.
Pfender M,Villinger H.2002.Miniaturized data loggers for deep sea sediment temperature gradient measurements.Marine Geology,186(3-4):557-570.
Qian Y P.1982.Terrestrial heat flow measurements and the results in the North of South China Sea.Marine Geology&Quaternary Geology(in Chinese),2(4):102-107.
Ratcliffe E H.1960.The thermal conductivities of ocean sediments.Journal of Geophysical Research,65(5):1535-1541.
Rybach L.1976.Radioactive heat production in rocks and its relation to other petrophysical parameters.Pure and Applied Geophysics,114(2):309-317.
Shi X B,Qiu X L,Xia K Y,et al.2003.Characteristics of surface heat flow in the South China Sea.JournalofAsianEarthSciences,22(3):265-277.
Taylor B,Hayes D E.1983.Origin and history of the South China Sea Basin.∥Hayes D E ed.The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands:Part 2.Washington,DC:American Geophysical Union,23-56.
Von Herzen R P,Maxwell A E.1959.The measurement of thermal conductivity of deep-sea sediments by a needle-probe method.Journal of Geophysical Research,64(10):1557-1563.
Xu X,Lu J A,Luo X H,et al.2005a.The marine heat flow survey and the result discussion in the northern part of South China Sea.Progress in Geophysics(in Chinese),20(2):562-565,doi:10.3969/j.issn.1004-2903.2005.02.057.
Xu X,Luo X H,Xiao B.2005b.Research on the methods&technique of marine heat flow measurement.Ocean Technology(in Chinese),24(1):77-81.
Xu X,Shi X B,Luo X H,et al.2006a.Data processing methods of marine geothermal measurement on the northern margin of the South China Sea.Geoscience(in Chinese),20(3):457-464.
Xu X,Shi X B,Luo X H,et al.2006b.Heat flow measurements in the Xisha trough of the South China Sea.Marine Geology&Quaternary Geology(in Chinese),26(4):51-58.
Yao B C,Zeng W J,Hayes D E,et al.1994.The Geological Memoir of South China Sea Surveyed Jointly by China&USA(in Chinese).Beijing:China University of Geosciences Press,140.
Yao B C.1997.The sea floor spreading in the SW subbasin of South China Sea and it’s tectonic significance.Geological Research of South China Sea(in Chinese),(9):20-36.
Zhao P,Wang J Y,Wang J A,et al.1995.Characteristics of heat production distribution in SE China.Acta Petrologica Sinica(in Chinese),11(3):292-305.
丁巍伟,陈汉林,杨树锋等.2003.南海西南次海盆与东部次海盆地质与地球物理分析.高校地质学报,8(3):268-279.
李家彪,丁巍伟,高金耀等.2011.南海新生代海底扩张的构造演化模式:来自高分辨率地球物理数据的新认识.地球物理学报,54(12):3004-3015,doi:10.3969/j.issn.0001-5733.2011.12.003.
李三忠,郭晓玉,侯方辉等.2004.洋中脊分段性及其拓展和叠接机制.海洋地质动态,20(11):19-28.
李细兵,吴振利,李家彪.2013.南海西南次海盆洋中脊分段特征.海洋地质与第四纪地质,33(3):101-107.
李亚敏,罗贤虎,徐行等.2010.南海北部陆坡深水区的海底原位热流测量.地球物理学报,53(9):2161-2170,doi:10.3969/j.issn.0001-5733.2010.09.016.
米立军,袁玉松,张功成等.2009.南海北部深水区地热特征及其成因.石油学报,30(1):27-32.
钱翼鹏.1982.南海北部地热流测量及其成果.海洋地质研究,2(4):102-107.
汪集旸,熊亮萍,黄少鹏.1996.沉积盆地中热的传递和地下水活动.第四纪研究,16(2):147-158.
徐行,陆敬安,罗贤虎等.2005a.南海北部海底热流测量及分析.地球物理学进展,20(2):562-565,doi:10.3969/j.issn.1004-2903.2005.02.057.
徐行,罗贤虎,肖波.2005b.海洋地热流测量技术及其方法研究.海洋技术,24(1):77-81.
徐行,施小斌,罗贤虎等.2006a.南海北部海底地热测量的数据处理方法.现代地质,20(3):457-464.
徐行,施小斌,罗贤虎等.2006b.南海西沙海槽地区的海底热流测量.海洋地质与第四纪地质,26(4):51-58.
姚伯初,曾维军,Hayes D E等.1994.中美合作调研南海地质专报GMSCS.武汉:中国地质大学出版社,140.
姚伯初.1997.南海西南海盆的海底扩张及其构造意义.南海地质研究,(9):20-36.
姚伯初.1999.南海西南海盆的岩石圈张裂模式探讨.海洋地质与第四纪地质,19(2):37-48.
赵平,汪集旸,汪缉安等.1995.中国东南地区岩石生热率分布特征.岩石学报,11(3):292-305.
Briais A,Tapponnier P,Pautot G.1989.Constraints of Sea beam data on crustal fabrics and seafloor spreading in the South China Sea.Earth and Planetary Science Letters,95(3-4):307-320.
Briais A,Patriat P,Tapponnier P.1993.Updated interpretation of magnetic anomalies and seafloor spreading stages in the South China Sea:Implications for the tertiary tectonics of Southeast Asia.Journal of Geophysical Research:Solid Earth,98(B4):6299-6328.
Hyndman R D,Erickson A J,VonHerzen R P.1974.Geothermal measurement on DSDP Leg 26.∥Davies T A,Luyendyk B Peds.Initial Reports of the Deep Sea Drilling Project 26.Washington:US Government Printing Office,675-742.
Li C F,Xu X,Lin J,et al.2014.Ages and magnetic structures of the South China Sea constrained by deep tow magnetic surveys and IODP expedition 349.Geochemistry,Geophysics,Geosystems,15(12):4958-4983.
Li C F,Lin J,Kulhanek D K,et al.2015.Proceedings of the international ocean discovery program,349:South China Sea tectonics.San Diego,CA:IODP,doi:10.14379/iodp.proc.349.105.2015.
Li J B,Ding W W,Gao J Y,et al.2011.Cenozoic evolution model of the sea-floor spreading in South China Sea:New constraints from high resolution geophysical data.Chinese Journal of Geophysics(in Chinese),54(12):3004-3015,doi:10.3969/j.issn.0001-5733.2011.12.003.
Li S Z,Guo X Y,Hou F H,et al.2004.Segmentation,propagation and overlapping at mid-oceanic ridge.Marine Geology Letters,20(11):19-28.
Li X B,Wu Z L,Li J B.2013.The preliminary study of segmentation of the mid-ocean ridge in southwest sub-basin of the south china sea.Marine Geology&Quaternary Geology(in Chinese),33(3):101-107.
Li Y M,Luo X H,Xu X,et al.2010.Seafloor in-situ heat flow measurements in the deep-water area of the northern slope,South China Sea.Chinese Journal of Geophysics(in Chinese),53(9):2161-2170,doi:10.3969/j.issn.0001-5733.2010.09.016.
Mi L J,Yuan Y S,Zhang G C,et al.2009.Characteristics and genesis of geothermal field in deep-water area of the northern South China Sea.Acta Petrolei Sinica(in Chinese),30(1):27-32.
Nissen S S,Hayes D E,Yao B C,et al.1995.Gravity,heat flow,and seismic constraints on the processes of crustal extension:Northern margin of the South China Sea.Journal of Geophysical Research:Solid Earth,100(B11):22447-22483.
Parsons B,Sclater J G.1977.An analysis of the variation of ocean floor bathymetry and heat flow with age.Journal of Geophysical Research,82(5):803-827.
Pfender M,Villinger H.2002.Miniaturized data loggers for deep sea sediment temperature gradient measurements.Marine Geology,186(3-4):557-570.
Qian Y P.1982.Terrestrial heat flow measurements and the results in the North of South China Sea.Marine Geology&Quaternary Geology(in Chinese),2(4):102-107.
Ratcliffe E H.1960.The thermal conductivities of ocean sediments.Journal of Geophysical Research,65(5):1535-1541.
Rybach L.1976.Radioactive heat production in rocks and its relation to other petrophysical parameters.Pure and Applied Geophysics,114(2):309-317.
Shi X B,Qiu X L,Xia K Y,et al.2003.Characteristics of surface heat flow in the South China Sea.JournalofAsianEarthSciences,22(3):265-277.
Taylor B,Hayes D E.1983.Origin and history of the South China Sea Basin.∥Hayes D E ed.The Tectonic and Geologic Evolution of Southeast Asian Seas and Islands:Part 2.Washington,DC:American Geophysical Union,23-56.
Von Herzen R P,Maxwell A E.1959.The measurement of thermal conductivity of deep-sea sediments by a needle-probe method.Journal of Geophysical Research,64(10):1557-1563.
Xu X,Lu J A,Luo X H,et al.2005a.The marine heat flow survey and the result discussion in the northern part of South China Sea.Progress in Geophysics(in Chinese),20(2):562-565,doi:10.3969/j.issn.1004-2903.2005.02.057.
Xu X,Luo X H,Xiao B.2005b.Research on the methods&technique of marine heat flow measurement.Ocean Technology(in Chinese),24(1):77-81.
Xu X,Shi X B,Luo X H,et al.2006a.Data processing methods of marine geothermal measurement on the northern margin of the South China Sea.Geoscience(in Chinese),20(3):457-464.
Xu X,Shi X B,Luo X H,et al.2006b.Heat flow measurements in the Xisha trough of the South China Sea.Marine Geology&Quaternary Geology(in Chinese),26(4):51-58.
Yao B C,Zeng W J,Hayes D E,et al.1994.The Geological Memoir of South China Sea Surveyed Jointly by China&USA(in Chinese).Beijing:China University of Geosciences Press,140.
Yao B C.1997.The sea floor spreading in the SW subbasin of South China Sea and it’s tectonic significance.Geological Research of South China Sea(in Chinese),(9):20-36.
Zhao P,Wang J Y,Wang J A,et al.1995.Characteristics of heat production distribution in SE China.Acta Petrologica Sinica(in Chinese),11(3):292-305.
丁巍伟,陈汉林,杨树锋等.2003.南海西南次海盆与东部次海盆地质与地球物理分析.高校地质学报,8(3):268-279.
李家彪,丁巍伟,高金耀等.2011.南海新生代海底扩张的构造演化模式:来自高分辨率地球物理数据的新认识.地球物理学报,54(12):3004-3015,doi:10.3969/j.issn.0001-5733.2011.12.003.
李三忠,郭晓玉,侯方辉等.2004.洋中脊分段性及其拓展和叠接机制.海洋地质动态,20(11):19-28.
李细兵,吴振利,李家彪.2013.南海西南次海盆洋中脊分段特征.海洋地质与第四纪地质,33(3):101-107.
李亚敏,罗贤虎,徐行等.2010.南海北部陆坡深水区的海底原位热流测量.地球物理学报,53(9):2161-2170,doi:10.3969/j.issn.0001-5733.2010.09.016.
米立军,袁玉松,张功成等.2009.南海北部深水区地热特征及其成因.石油学报,30(1):27-32.
钱翼鹏.1982.南海北部地热流测量及其成果.海洋地质研究,2(4):102-107.
汪集旸,熊亮萍,黄少鹏.1996.沉积盆地中热的传递和地下水活动.第四纪研究,16(2):147-158.
徐行,陆敬安,罗贤虎等.2005a.南海北部海底热流测量及分析.地球物理学进展,20(2):562-565,doi:10.3969/j.issn.1004-2903.2005.02.057.
徐行,罗贤虎,肖波.2005b.海洋地热流测量技术及其方法研究.海洋技术,24(1):77-81.
徐行,施小斌,罗贤虎等.2006a.南海北部海底地热测量的数据处理方法.现代地质,20(3):457-464.
徐行,施小斌,罗贤虎等.2006b.南海西沙海槽地区的海底热流测量.海洋地质与第四纪地质,26(4):51-58.
姚伯初,曾维军,Hayes D E等.1994.中美合作调研南海地质专报GMSCS.武汉:中国地质大学出版社,140.
姚伯初.1997.南海西南海盆的海底扩张及其构造意义.南海地质研究,(9):20-36.
姚伯初.1999.南海西南海盆的岩石圈张裂模式探讨.海洋地质与第四纪地质,19(2):37-48.
赵平,汪集旸,汪缉安等.1995.中国东南地区岩石生热率分布特征.岩石学报,11(3):292-305.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |