塔里木盆地早二叠世玄武岩火山机构的三维地震解释与结构分析
|
摘要
将高精度的钻孔测井数据与三维反射地震数据相结合,对塔里木盆地中部47井区早二叠世大陆溢流玄武岩(CFB)火山机构进行三维地震解释研究。通过时间剖面层位追索和速度分析等方法,对火山机构的形态、结构和岩性组成进行解析,确定塔里木盆地中部47井区火山机构下方存在玄武质高波速侵入体,其平均地震纵波速度为5800 m/s,围岩碎屑岩的平均地震纵波速度为3500 m/s。通过计算两个标志层(二叠系-三叠系界面"P-top"和生屑灰岩顶面"BL-top")的测井深度,确定玄武质侵入体导致上部标志层相对于下部标志层发生了159.1 m的向上抬升,这相当于火山机构处地层的变形抬升量。进一步利用"速度上拉"效应计算得到的玄武质侵入体总厚度为167.7 m,与测井计算的抬升量基本上一致。研究结果表明,塔中47火山机构的地层抬升是由于深部岩浆注入,导致上覆地层发生"强制褶皱"而形成,与Karoo大火成岩省、北大西洋火成岩省等大陆溢流玄武岩在地壳浅部的就位方式一致。
The volcano edifices from Tazhong-47 exploring area in the middle of Tarim basin are interpreted by 3-D seismological reflection data coupled with physical drilling well logs. Based on seismic profile interpretation and velocity analysis, the structure of the volcano edifices of continental flood basalt(CFB) are studied. The result shows that reflectors beneath the Tazhong-47 volcanic edifice are corresponding to basaltic intrusions, which have average velocity of 5800 m/s, and the clastic wall rocks have average velocity of 3500 m/s. Based on the calculation of the stratigraphical thickness between the two horizontal markers(Permian-Triassic boundary as named "P-top" and top of bioclastic limestone as named "BL-top") at drilling well, it is found that the basaltic intrusions make the upper layer relative to the lower layer marks move the 159.1 m upward. This is equal to the uplift extent. By using the "velocity pull-up(VPU)" effect, the total thickness of the basaltic sills is calculated to be 167.7 m, which is similar to the uplift extent. This similarity suggests that the uplift at the volcanic center was the result of "forced folding" caused by the intrusion of the magma. This emplacement style is the same as that of the Karoo large igneous province and the North Atlantic igneous province.
The volcano edifices from Tazhong-47 exploring area in the middle of Tarim basin are interpreted by 3-D seismological reflection data coupled with physical drilling well logs. Based on seismic profile interpretation and velocity analysis, the structure of the volcano edifices of continental flood basalt(CFB) are studied. The result shows that reflectors beneath the Tazhong-47 volcanic edifice are corresponding to basaltic intrusions, which have average velocity of 5800 m/s, and the clastic wall rocks have average velocity of 3500 m/s. Based on the calculation of the stratigraphical thickness between the two horizontal markers(Permian-Triassic boundary as named "P-top" and top of bioclastic limestone as named "BL-top") at drilling well, it is found that the basaltic intrusions make the upper layer relative to the lower layer marks move the 159.1 m upward. This is equal to the uplift extent. By using the "velocity pull-up(VPU)" effect, the total thickness of the basaltic sills is calculated to be 167.7 m, which is similar to the uplift extent. This similarity suggests that the uplift at the volcanic center was the result of "forced folding" caused by the intrusion of the magma. This emplacement style is the same as that of the Karoo large igneous province and the North Atlantic igneous province.
引文
[1]Ernst R E.Large igneous provinces.London:Cambridge University Press,2014
[2]White J D L,Bryan S E,Ross P S,et al.Physical volcanology of continental large igneous provinces:update and review.London:Special Publications of Iavcei,2009:291-321
[3]Ernst R E,Head J W,Parfitt E,et al.Giant radiating dyke swarms on Earth and Venus.Earth-Science Reviews,1995,39(1/2):1-58
[4]Dragoni M,Lanza R,Tallarico A.Magnetic anisotropy produced by magma flow:theoretical model and experimental data from Ferrar dolerite sills(Antarctica).Geophysical Journal International,1997,128(1):230-240
[5]Elliot D H,Fleming T H,Kyle P R,et al.Longdistance transport of magmas in the Jurassic Ferrar large igneous province,Antarctica.Earth Planet Science Letter,1999,167(1/2):89-104
[6]Leat P T.On the long-distance transport of Ferrar magmas.Geol Soc London Spec Publ,2008,302(1):45-61
[7]Muirhead J D,Airoldi G,White J D L,et al.Cracking the lid:sill-fed dikes are the likely feeders of flood basalt eruptions.Earth Planet Science Letter,2014,406:187-197
[8]Thomson K,Hutton D.Geometry and growth of sill complexes:insights using 3D seismic from the North Rockall Trough.Bulletin of Volcanology,2004,66(4):364-375
[9]Chevallier L,Woodford A.Morpho-tectonics and mechanism of emplacement of the dolerite rings and sills of the western Karoo,South Africa.South African Journal of Geology,1999,102(1):43-54
[10]Duraiswami R A,Shaikh T N.Geology of the saucershaped sill near Mahad,western Deccan Traps,India,and its significance to the Flood Basalt Model.Bulletin of Volcanology,2013,75(7):731-749
[11]Polteau S,Ferre E C,Planke S,et al.How are saucershaped sills emplaced?Constraints from the Golden Valley Sill,South Africa.Journal of Geophysical Research-Solid Earth,2008,113(B12):104-117
[12]Polteau S,Mazzini A,Galland O,et al.Saucer-shaped intrusions:occurrences,emplacement and implications.Earth Planet Sci Lett,2008,266(1/2):195-204
[13]Magee C,Jackson C A L,Schofield N.Diachronous sub-volcanic intrusion along deep-water margins:insights from the Irish Rockall Basin.Basin Res,2014,26(1):85-105
[14]Passey S,Hitchen K.Cenozoic(igneous)//Ritchie J D,Ziska H,Johnson H,et al.Geology of the FaroeShetland basin and adjacent areas.London:British Geological Survey Research Report,2011:209-228
[15]Svensen H,Planke S,Malthe-Sorenssen A,et al.Release of methane from a volcanic basin as a mechanism for initial Eocene global warming.Nature,2004,429:542-545
[16]Planke S,Rasmussen T,Rey S,et al.Seismic characteristics and distribution of volcanic intrusions and hydrothermal vent complexes in the V?ring and M?re basins//Dore A G,Vining B A.Petroleum geology:north-west Europe and global perspectives.Proceedings of the 6th Petroleum Geology Conference.London:Geological Society,2005:833-844
[17]Pollard D D,Johnson A M.Mechanics of growth of some laccolithic intrusions in Henry mountains,Utah.2.Bending and failure of overburden layers and sill formation.Tectonophysics,1973,18(3/4):311-354
[18]Trude J,Cartwright J,Davies R J,et al.New technique for dating igneous sills.Geology,2003,31(9):813-816
[19]Hansen D M,Cartwright J.The three-dimensional geometry and growth of forced folds above saucershaped igneous sills.Journal of Structural Geology,2006,28(8):1520-1535
[20]Jackson C A L,Schofield N,Golenkov B.Geometry and controls on the development of igneous sillrelated forced folds:a 2-D seismic reflection case study from offshore southern Australia.GSAMB,2013,125(11/12):1874-1890
[21]Magee C,Briggs F,Jackson C A L.Lithological controls on igneous intrusion-induced ground deformation.Journal of the Geological Society,2013,170(6):853-856
[22]Cosgrove J W.Forced folds and fractures:an intro-duction.Geological Society London Special Publications,1999,169(1):1-6
[23]Jackson C A L,Lewis M M.Structural style and evolution of a salt-influenced rift basin margin;the impact of variations in salt composition and the role of polyphase extension.Basin Res,2016,28(1):81-102
[24]Lewis M M,Jackson C A L,Gawthorpe R L.Saltinfluenced normal fault growth and forced folding:the Stavanger fault system,North Sea.Journal of Structural Geology,2013,54:156-173
[25]Cosgrove J W,Ameen M S.Forced folds and fractures.London:The Geological Society,1999
[26]杨树锋,陈汉林,厉子龙,等.塔里木早二叠世大火成岩省.中国科学:地球科学,2014,44(2):187-199
[27]Tian W,Campbell I H,Allen C M,et al.The Tarim picrite-basalt-rhyolite suite,a Permian flood basalt from northwest China with contrasting rhyolites produced by fractional crystallization and anatexis.Contributions to Mineralogy and Petrology,2010,160(3):407-425
[28]Xu Y G,Wei X,Luo Z Y,et al.The Early Permian Tarim Large Igneous Province:main characteristics and a plume incubation model.Litho,2014,204:20-35
[29]Usui Y,Tian W.Paleomagnetic directional groups and paleointensity from the flood basalt in the Tarim large igneous province:implications for eruption frequency.Earth,Planets and Space,2017,69(1):14-27
[30]Chen M M,Tian W,Suzuki K,et al.Peridotite and pyroxenite xenoliths from Tarim,NW China:evidences for melt depletion and mantle refertilization in the mantle source region of the Tarim flood basalt.Lithos,2014,204:97-111
[31]Yang J,Zhu W,Guan D,et al.3D seismic interpretation of subsurface eruptive centers in a Permian large igneous province,Tazhong Uplift,central Tarim Basin,NW China.International Journal of Earth Sciences,2016,105(8):2311-2326
[32]Wang L,Tian W,Shi Y M,et al.Volcanic structure of the Tarim flood basalt revealed through 3-D seismological imaging.Sci Bull,2015,60(16):1448-1456
[33]Walker G P L,Huntingdon A T,Sanders A T,et al.Length of lava flows[and discussion].Philosophical Transactions of the Royal Society of London,Series A:Mathematical and Physical Sciences,1973,274:107-118
[34]Widess M B.How thin is a thin bed?.Geophysics,1973,38(6):1176-1180
[35]Smallwood J R,Maresh J.The properties,morphology and distribution of igneous sills:modelling,borehole data and 3D seismic from the Faroe-Shetland area.Geological Society London Special Publications,2002,197(1):271-306
[36]Symonds P,Planke S,Frey O,et al.Volcanic evolution of the Western Australian continental margin and its implications for basin development.The Sedimentary Basins of Western Australia,1998,2(1):33-54
[37]Mihut D,Muller R D.Volcanic margin formation and Mesozoic rift propagators in the Cuvier Abyssal Plain off Western Australia.Journal of Geophysical Research-Solid Earth,1998,103(B11):27135-27149
[38]Magee C,Hunt Stewart E,Jackson C A L.Volcano growth mechanisms and the role of sub-volcanic intrusions:insights from 2D seismic reflection data.Earth Planet Science Letter,2013,373:41-53
[39]Jackson C A L.Seismic reflection imaging and controls on the preservation of ancient sill-fed magmatic vents.Journal of the Geological Society,2012,169(5):503-506
[40]De Silva S,Lindsay J M.Chapter 15:Primary volcanic landforms//Sigurdsson H.The encyclopedia of volcanoes.2nd ed.Amsterdam:Academic Press,2015:273-297
[2]White J D L,Bryan S E,Ross P S,et al.Physical volcanology of continental large igneous provinces:update and review.London:Special Publications of Iavcei,2009:291-321
[3]Ernst R E,Head J W,Parfitt E,et al.Giant radiating dyke swarms on Earth and Venus.Earth-Science Reviews,1995,39(1/2):1-58
[4]Dragoni M,Lanza R,Tallarico A.Magnetic anisotropy produced by magma flow:theoretical model and experimental data from Ferrar dolerite sills(Antarctica).Geophysical Journal International,1997,128(1):230-240
[5]Elliot D H,Fleming T H,Kyle P R,et al.Longdistance transport of magmas in the Jurassic Ferrar large igneous province,Antarctica.Earth Planet Science Letter,1999,167(1/2):89-104
[6]Leat P T.On the long-distance transport of Ferrar magmas.Geol Soc London Spec Publ,2008,302(1):45-61
[7]Muirhead J D,Airoldi G,White J D L,et al.Cracking the lid:sill-fed dikes are the likely feeders of flood basalt eruptions.Earth Planet Science Letter,2014,406:187-197
[8]Thomson K,Hutton D.Geometry and growth of sill complexes:insights using 3D seismic from the North Rockall Trough.Bulletin of Volcanology,2004,66(4):364-375
[9]Chevallier L,Woodford A.Morpho-tectonics and mechanism of emplacement of the dolerite rings and sills of the western Karoo,South Africa.South African Journal of Geology,1999,102(1):43-54
[10]Duraiswami R A,Shaikh T N.Geology of the saucershaped sill near Mahad,western Deccan Traps,India,and its significance to the Flood Basalt Model.Bulletin of Volcanology,2013,75(7):731-749
[11]Polteau S,Ferre E C,Planke S,et al.How are saucershaped sills emplaced?Constraints from the Golden Valley Sill,South Africa.Journal of Geophysical Research-Solid Earth,2008,113(B12):104-117
[12]Polteau S,Mazzini A,Galland O,et al.Saucer-shaped intrusions:occurrences,emplacement and implications.Earth Planet Sci Lett,2008,266(1/2):195-204
[13]Magee C,Jackson C A L,Schofield N.Diachronous sub-volcanic intrusion along deep-water margins:insights from the Irish Rockall Basin.Basin Res,2014,26(1):85-105
[14]Passey S,Hitchen K.Cenozoic(igneous)//Ritchie J D,Ziska H,Johnson H,et al.Geology of the FaroeShetland basin and adjacent areas.London:British Geological Survey Research Report,2011:209-228
[15]Svensen H,Planke S,Malthe-Sorenssen A,et al.Release of methane from a volcanic basin as a mechanism for initial Eocene global warming.Nature,2004,429:542-545
[16]Planke S,Rasmussen T,Rey S,et al.Seismic characteristics and distribution of volcanic intrusions and hydrothermal vent complexes in the V?ring and M?re basins//Dore A G,Vining B A.Petroleum geology:north-west Europe and global perspectives.Proceedings of the 6th Petroleum Geology Conference.London:Geological Society,2005:833-844
[17]Pollard D D,Johnson A M.Mechanics of growth of some laccolithic intrusions in Henry mountains,Utah.2.Bending and failure of overburden layers and sill formation.Tectonophysics,1973,18(3/4):311-354
[18]Trude J,Cartwright J,Davies R J,et al.New technique for dating igneous sills.Geology,2003,31(9):813-816
[19]Hansen D M,Cartwright J.The three-dimensional geometry and growth of forced folds above saucershaped igneous sills.Journal of Structural Geology,2006,28(8):1520-1535
[20]Jackson C A L,Schofield N,Golenkov B.Geometry and controls on the development of igneous sillrelated forced folds:a 2-D seismic reflection case study from offshore southern Australia.GSAMB,2013,125(11/12):1874-1890
[21]Magee C,Briggs F,Jackson C A L.Lithological controls on igneous intrusion-induced ground deformation.Journal of the Geological Society,2013,170(6):853-856
[22]Cosgrove J W.Forced folds and fractures:an intro-duction.Geological Society London Special Publications,1999,169(1):1-6
[23]Jackson C A L,Lewis M M.Structural style and evolution of a salt-influenced rift basin margin;the impact of variations in salt composition and the role of polyphase extension.Basin Res,2016,28(1):81-102
[24]Lewis M M,Jackson C A L,Gawthorpe R L.Saltinfluenced normal fault growth and forced folding:the Stavanger fault system,North Sea.Journal of Structural Geology,2013,54:156-173
[25]Cosgrove J W,Ameen M S.Forced folds and fractures.London:The Geological Society,1999
[26]杨树锋,陈汉林,厉子龙,等.塔里木早二叠世大火成岩省.中国科学:地球科学,2014,44(2):187-199
[27]Tian W,Campbell I H,Allen C M,et al.The Tarim picrite-basalt-rhyolite suite,a Permian flood basalt from northwest China with contrasting rhyolites produced by fractional crystallization and anatexis.Contributions to Mineralogy and Petrology,2010,160(3):407-425
[28]Xu Y G,Wei X,Luo Z Y,et al.The Early Permian Tarim Large Igneous Province:main characteristics and a plume incubation model.Litho,2014,204:20-35
[29]Usui Y,Tian W.Paleomagnetic directional groups and paleointensity from the flood basalt in the Tarim large igneous province:implications for eruption frequency.Earth,Planets and Space,2017,69(1):14-27
[30]Chen M M,Tian W,Suzuki K,et al.Peridotite and pyroxenite xenoliths from Tarim,NW China:evidences for melt depletion and mantle refertilization in the mantle source region of the Tarim flood basalt.Lithos,2014,204:97-111
[31]Yang J,Zhu W,Guan D,et al.3D seismic interpretation of subsurface eruptive centers in a Permian large igneous province,Tazhong Uplift,central Tarim Basin,NW China.International Journal of Earth Sciences,2016,105(8):2311-2326
[32]Wang L,Tian W,Shi Y M,et al.Volcanic structure of the Tarim flood basalt revealed through 3-D seismological imaging.Sci Bull,2015,60(16):1448-1456
[33]Walker G P L,Huntingdon A T,Sanders A T,et al.Length of lava flows[and discussion].Philosophical Transactions of the Royal Society of London,Series A:Mathematical and Physical Sciences,1973,274:107-118
[34]Widess M B.How thin is a thin bed?.Geophysics,1973,38(6):1176-1180
[35]Smallwood J R,Maresh J.The properties,morphology and distribution of igneous sills:modelling,borehole data and 3D seismic from the Faroe-Shetland area.Geological Society London Special Publications,2002,197(1):271-306
[36]Symonds P,Planke S,Frey O,et al.Volcanic evolution of the Western Australian continental margin and its implications for basin development.The Sedimentary Basins of Western Australia,1998,2(1):33-54
[37]Mihut D,Muller R D.Volcanic margin formation and Mesozoic rift propagators in the Cuvier Abyssal Plain off Western Australia.Journal of Geophysical Research-Solid Earth,1998,103(B11):27135-27149
[38]Magee C,Hunt Stewart E,Jackson C A L.Volcano growth mechanisms and the role of sub-volcanic intrusions:insights from 2D seismic reflection data.Earth Planet Science Letter,2013,373:41-53
[39]Jackson C A L.Seismic reflection imaging and controls on the preservation of ancient sill-fed magmatic vents.Journal of the Geological Society,2012,169(5):503-506
[40]De Silva S,Lindsay J M.Chapter 15:Primary volcanic landforms//Sigurdsson H.The encyclopedia of volcanoes.2nd ed.Amsterdam:Academic Press,2015:273-297