青藏高原东缘保山地块沧源新生代中酸性侵入岩年代学、岩石成因与地块挤出
|
摘要
为探讨保山地块新生代岩浆侵位时代,揭示其成因和形成动力学机制,重建保山地块新生代演化历史,对保山地块东南缘沧源新生代岩浆岩中部分中酸性岩体和岩墙开展了岩石学、锆石U-Pb年代学和地球化学研究。结果表明,沧源地区新生代中酸性岩体和岩墙均侵位于40~41Ma,与澜沧新生代花岗质侵入岩年龄相当,为保山地块新生代早期岩浆活动的重要组成。沧源和澜沧新生代岩浆岩总体具有较强的轻-重稀土、特别是中-重稀土分馏,无明显Sr、Eu负异常,具高的Sr/Y、La/Yb、Gd/Yb值,与C型埃达克岩类似。样品的86Sri/87Sri为0.7065~0.7103,εNd(t)为-3.6~-5.6。沧源新生代岩浆岩很可能来自石榴斜长角闪岩源区在30~40km深度的部分熔融。通过岩相学和地球化学分析,首次在沧源新生代岩浆岩中识别出~41Ma的A型花岗岩。结合区域构造-岩浆研究成果,认为沧源-澜沧新生代岩浆带与青藏高原碰撞导致的东部岩石圈块体南东向挤出作用存在密切联系。
In order to investigate the geochronology,petrogenesis and geodynamicsettingof the Cenozoic igneous rocks in Baoshan block,we have concentrated on the petrology,zircon U-Pb chronology and whole-rock geochemical composition of the Early Cenozoic igneous rock in Cangyuan,southeastern Baoshan block.The results of dating indicate that the intermediate to flesic intrusions and dykes in Cangyuan emplaced at 40-41Ma,synchronous with those in Lancang region.The Early Cenozoic igneous rock in Cangyuan and Lancang exhibits high Sr/Y,La/Yb,Gd/Yb ratios and significant REE fractionation,with no significant Sr,Eu negative anomaly,similar to C-type adakite.They have enriched initial86Sr/87 Sr ratios of 0.7065-0.7103,εNd(t) values of-3.6 to-5.6.We infer that the Cangyuan Cenozoic magmatism resulted from partial melting of garnet amphibolite in lower crust at a depth of 30 ~ 40km.In addition,we report for the first time that there has ~ 41Ma A-type granite in Cangyuan region in this study.The early Cenozoic igneous rock in both Cangyuan and Lancang have close spatial,temporal and possibly has genetic linkage with the eastward extrusion of Tibet.
In order to investigate the geochronology,petrogenesis and geodynamicsettingof the Cenozoic igneous rocks in Baoshan block,we have concentrated on the petrology,zircon U-Pb chronology and whole-rock geochemical composition of the Early Cenozoic igneous rock in Cangyuan,southeastern Baoshan block.The results of dating indicate that the intermediate to flesic intrusions and dykes in Cangyuan emplaced at 40-41Ma,synchronous with those in Lancang region.The Early Cenozoic igneous rock in Cangyuan and Lancang exhibits high Sr/Y,La/Yb,Gd/Yb ratios and significant REE fractionation,with no significant Sr,Eu negative anomaly,similar to C-type adakite.They have enriched initial86Sr/87 Sr ratios of 0.7065-0.7103,εNd(t) values of-3.6 to-5.6.We infer that the Cangyuan Cenozoic magmatism resulted from partial melting of garnet amphibolite in lower crust at a depth of 30 ~ 40km.In addition,we report for the first time that there has ~ 41Ma A-type granite in Cangyuan region in this study.The early Cenozoic igneous rock in both Cangyuan and Lancang have close spatial,temporal and possibly has genetic linkage with the eastward extrusion of Tibet.
引文
Aikman A B,Harrison T M,Lin D.2008.Evidence for early(>44Ma)Himalayan crustal thickening,Tethyan Himalaya,southeastern Tibet.Earth and Planetary Science Letters,274(1-2):14-23
Akciz S,Burchfiel B C,Crowley J L,Yin J Y,Chen L Z.2008.Geometry,kinematics,and regional significance of the Chong Shan shear zone,Eastern Himalayan Syntaxis,Yunnan,China.Geosphere,4(1):292-314
Burchfiel B C,Chen Z L.2012.Tectonics of the southeastern Tibetan Plateau and its adjacent foreland.Boulder,Colorado:The Geological Society of America,1-164
Chen F K,Li X H,Wang X L,Li Q L,Siebel W.2007.Zircon age and Nd-Hf isotopic composition of the Yunnan Tethyan belt,southwestern China.International Journal of Earth Sciences,96(6):1179-1194
Chen X C,Hu R Z,Bi X W,Zhong H,Lan J B,Zhao C H,Zhu J J.2015.Petrogenesis of metaluminous A-type granitoids in the Tengchong-Lianghe tin belt of southwestern China:Evidences from zircon U-Pb ages and Hf-O isotopes,and whole-rock Sr-Nd isotopes.Lithos,212-215:93-110
Deng J,Wang Q F,Li G J,Santosh M.2014.Cenozoic tectonomagmatic and metallogenic processes in the Sanjiang region,southwestern China.Earth-Science Reviews,138:268-299
Eby G N.1992.Chemical subdivision of the A-type granitoids:Petrogenetic and tectonic implications.Geology,20(7):641-644
Foley S,Tiepolo M,Vannucci R.2002.Growth of early continental crust controlled by melting of amphibolite in subduction zones.Nature,417(6891):837-840
Gao S,Rudnick R L,Yuan H L,Liu X M,Liu Y S,Xu W L,Ling W L,Ayers J,Wang X C,Wang Q H.2004.Recycling lower continental crust in the North China craton.Nature,432(7019):892-897
Green T H.1995.Significance of Nb/Ta as an indicator of geochemical processes in the crust-mantle system.Chemical Geology,120(3-4):347-359
Kincaid C,Griffiths R W.2003.Laboratory models of the thermal evolution of the mantle during rollback subduction.Nature,425(6953):58-62
King P L,White A J R,Chappell B W,Allen C M.1997.Characterization and origin of aluminous A-type granites from the Lachlan Fold Belt,southeastern Australia.Journal of Petrology,38(3):371-391
Liu Y S,Hu Z C,Zong K Q,Gao C G,Gao S,Xu J,Chen H H.2010.Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS.Chinese Science Bulletin,55(15):1535-1546
Martin H.1999.Adakitic magmas:Modern analogues of Archaean granitoids.Lithos,46(3):411-429
Meinhold G.2010.Rutile and its applications in earth sciences.EarthScience Reviews,102(1-2):1-28
Moyen J F.2009.High Sr/Y and La/Yb ratios:The meaning of the“adakitic signature”.Lithos,112(3-4):556-574
Qian Q,Hermann J.2013.Partial melting of lower crust at 10-15kbar:Constraints on adakite and TTG formation.Contributions to Mineralogy and Petrology,165(6):1195-1224
Rohrmann A,Kapp P,Carrapa B,Reiners P W,Guynn J,Ding L,Heizler M.2012.Thermochronologic evidence for plateau formation in central Tibet by 45Ma.Geology,40(2):187-190
Sun S S,Mc Donough W F.1989.Chemical and isotopic systematics of oceanic basalts:Implications for mantle composition and processes.Geological Society,London,Special Publications,42(1):313-345
Thatcher W.2007.Microplate model for the present-day deformation of Tibet.Journal of Geophysical Research:Solid Earth(1978-2012),112(B1),doi:10.1029/2005JB004244
Wang C S,Dai J G,Zhao X X,Li Y L,Graham S A,He D F,Ran B,Meng J.2014.Outward-growth of the Tibetan Plateau during the Cenozoic:A review.Tectonophysics,621:1-43
Wang Y J,Fan W M,Zhang Y H,Peng T P,Chen X Y,Xu Y G.2006.Kinematics and40Ar-39Ar geochronology of the Gaoligong and Chongshan shear systems,western Yunnan,China:Implications for early Oligocene tectonic extrusion of SE Asia.Tectonophysics,418(3-4):235-254
Watson E B,Harrison T M.1983.Zircon saturation revisited:Temperature and composition effects in a variety of crustal magma types.Earth and Planetary Science Letters,64(2):295-304
Whalen J B,Currie K L,Chappell B W.1987.A-type granites:Geochemical characteristics,discrimination and petrogenesis.Contributions to Mineralogy and Petrology,95(4):407-419
Xu Y G,Lan J B,Yang Q J,Huang XL,Qiu H N.2008.Eocene breakoff of the Neo-Tethyan slab as inferred from intraplate-type mafic dykes in the Gaoligong orogenic belt,eastern Tibet.Chemical Geology,255(3-4):439-453
Xu Z Q,Wang Q,Cai Z H,Dong H W,Li H Q,Chen X J,Duan X D,Cao H,Li J,Burg JP.2015.Kinematics of the Tengchong Terrane in SE Tibet from the late Eocene to early Miocene:Insights from coeval mid-crustal detachments and strike-slip shear zones.Tectonophysics,665:127-148
Yamaji A.2003.Slab rollback suggested by latest Miocene to Pliocene forearc stress and migration of volcanic front in southern Kyushu,northern Ryukyu Arc.Tectonophysics,364(1-2):9-24
Yin A,Harrison T M.2000.Geologic evolution of the Himalayan-Tibetan orogen.Annual Review of Earth and Planetary Sciences,28(1):211-280
Zhang B,Zhang J J,Zhong D L.2010.Structure,kinematics and ages of transpression during strain-partitioning in the Chongshan shear zone,western Yunnan,China.Journal of Structural Geology,32(4):445-463
Zhang B,Zhang J J,Chang Z F,Wang X X,Cai F L,Lai Q Z.2012.The Biluoxueshan transpressive deformation zone monitored by synkinematic plutons,around the Eastern Himalayan Syntaxis.Tectonophysics,574-575:158-180
Zhu DC,Wang Q,Zhao ZD,Chung SL,Cawood P A,Niu Y L,Liu SA,Wu FY,Mo XX.2015.Magmatic record of India-Asia collision.Scientific Reports,5:14289
常承法.1985.青藏高原的板块构造.矿物岩石地球化学通报,4(2):56-58
陈珲,李峰,坚润堂,罗思亮,姚巍.2010.云南澜沧老厂花岗斑岩锆石SHRIMP定年及其地质意义.地质学报,84(4):485-491
董方浏,侯增谦,高永丰,曾普胜,蒋成兴.2006.滇西腾冲新生代花岗岩:成因类型与构造意义.岩石学报,22(4):927-937
董美玲,董国臣,莫宣学,朱弟成,聂飞,于峻川,王鹏,罗微.2013.滇西保山地块中-新生代岩浆作用及其构造意义.岩石学报,29(11):3901-3913
高永娟,林仕良,丛峰,邹光富,陈莉,谢韬.2014.滇西梁河地区闪长岩LA-ICP-MS锆石U-Pb年龄,Hf同位素特征及其地质意义.地质通报,33(10):1482-1491
侯可军,李延河,邹天人,曲晓明,石玉若,谢桂青.2008.LA-MC-ICP-MS锆石Hf同位素的分析方法及地质应用.岩石学报,23(10):2595-2604
侯可军,李延河,田有荣.2009.LA-MC-ICP-MS锆石微区原位U-Pb定年技术.矿床地质,28(4):481-492
黄静宁,陈永清,Zhai X M,卢映祥,谢永富,程志中.2011.滇西保山地块双脉地晚始新世过铝质花岗岩:锆石SHRIMP U-Pb定年、地球化学和成因.中国科学:地球科学,41(4):452-467
金志升,黄智龙,朱成明.1997.云南三江地区富碱侵入岩与煌斑岩的同源性.矿物岩石地球化学通报,16(4):222-224
李峰,陈珲,鲁文举,罗思亮.2010.云南澜沧老厂花岗斑岩形成年龄及地质意义.大地构造与成矿学,34(1):84-91
李再会,王立全,林仕良,丛峰,谢韬,邹光富.2012.滇西高黎贡剪切带内花岗质糜棱岩LA-ICP-MS锆石U-Pb年龄及其构造意义.地质通报,31(8):1287-1295
林进展,曹华文,张寿庭,刘瑞萍,肖常先,杨宽.2015.青藏高原东南缘腾冲来利山A型花岗岩地球化学特征、锆石U-Pb定年及其构造意义.大地构造与成矿学,39(5):959-971
沈敢富.1992.酸性岩浆岩成岩成矿机制新探:以“三江”地区为例.矿物岩石地球化学通报,11(2):86-87
唐渊,尹福光,王立全,王冬兵,廖世勇,孙志明,孙洁.2013.滇西崇山剪切带南段左行走滑作用的构造特征及时代约束.岩石学报,29(4):1311-1324
杨帆,李峰,陈珲,肖静珊,赵晓勇.2012.云南澜沧老厂隐伏花岗斑岩体地球化学特征及构造环境.岩石矿物学杂志,31(1):39-49
杨启军,徐义刚,黄小龙,罗震宇,石玉若.2009.滇西腾冲-梁河地区花岗岩的年代学、地球化学及其构造意义.岩石学报,25(5):1092-1104
喻学惠,肖晓牛,杨贵来,莫宣学,曾普胜,王晋璐.2008.滇西″三江″南段几个花岗岩的锆石SHIRMP U-Pb定年及其地质意义.岩石学报,24(2):377-383
云南省地质调查院.2004.1︰25万临沧幅区域地质图及调查报告
邹光富,毛英,邹鑫,林仕良,丛峰,李再会,谢韬,高永娟.2013.滇西芒市江东花岗岩体的锆石U-Pb年龄、地球化学特征及构造意义.地质学报,87(11):1635-1646
Akciz S,Burchfiel B C,Crowley J L,Yin J Y,Chen L Z.2008.Geometry,kinematics,and regional significance of the Chong Shan shear zone,Eastern Himalayan Syntaxis,Yunnan,China.Geosphere,4(1):292-314
Burchfiel B C,Chen Z L.2012.Tectonics of the southeastern Tibetan Plateau and its adjacent foreland.Boulder,Colorado:The Geological Society of America,1-164
Chen F K,Li X H,Wang X L,Li Q L,Siebel W.2007.Zircon age and Nd-Hf isotopic composition of the Yunnan Tethyan belt,southwestern China.International Journal of Earth Sciences,96(6):1179-1194
Chen X C,Hu R Z,Bi X W,Zhong H,Lan J B,Zhao C H,Zhu J J.2015.Petrogenesis of metaluminous A-type granitoids in the Tengchong-Lianghe tin belt of southwestern China:Evidences from zircon U-Pb ages and Hf-O isotopes,and whole-rock Sr-Nd isotopes.Lithos,212-215:93-110
Deng J,Wang Q F,Li G J,Santosh M.2014.Cenozoic tectonomagmatic and metallogenic processes in the Sanjiang region,southwestern China.Earth-Science Reviews,138:268-299
Eby G N.1992.Chemical subdivision of the A-type granitoids:Petrogenetic and tectonic implications.Geology,20(7):641-644
Foley S,Tiepolo M,Vannucci R.2002.Growth of early continental crust controlled by melting of amphibolite in subduction zones.Nature,417(6891):837-840
Gao S,Rudnick R L,Yuan H L,Liu X M,Liu Y S,Xu W L,Ling W L,Ayers J,Wang X C,Wang Q H.2004.Recycling lower continental crust in the North China craton.Nature,432(7019):892-897
Green T H.1995.Significance of Nb/Ta as an indicator of geochemical processes in the crust-mantle system.Chemical Geology,120(3-4):347-359
Kincaid C,Griffiths R W.2003.Laboratory models of the thermal evolution of the mantle during rollback subduction.Nature,425(6953):58-62
King P L,White A J R,Chappell B W,Allen C M.1997.Characterization and origin of aluminous A-type granites from the Lachlan Fold Belt,southeastern Australia.Journal of Petrology,38(3):371-391
Liu Y S,Hu Z C,Zong K Q,Gao C G,Gao S,Xu J,Chen H H.2010.Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS.Chinese Science Bulletin,55(15):1535-1546
Martin H.1999.Adakitic magmas:Modern analogues of Archaean granitoids.Lithos,46(3):411-429
Meinhold G.2010.Rutile and its applications in earth sciences.EarthScience Reviews,102(1-2):1-28
Moyen J F.2009.High Sr/Y and La/Yb ratios:The meaning of the“adakitic signature”.Lithos,112(3-4):556-574
Qian Q,Hermann J.2013.Partial melting of lower crust at 10-15kbar:Constraints on adakite and TTG formation.Contributions to Mineralogy and Petrology,165(6):1195-1224
Rohrmann A,Kapp P,Carrapa B,Reiners P W,Guynn J,Ding L,Heizler M.2012.Thermochronologic evidence for plateau formation in central Tibet by 45Ma.Geology,40(2):187-190
Sun S S,Mc Donough W F.1989.Chemical and isotopic systematics of oceanic basalts:Implications for mantle composition and processes.Geological Society,London,Special Publications,42(1):313-345
Thatcher W.2007.Microplate model for the present-day deformation of Tibet.Journal of Geophysical Research:Solid Earth(1978-2012),112(B1),doi:10.1029/2005JB004244
Wang C S,Dai J G,Zhao X X,Li Y L,Graham S A,He D F,Ran B,Meng J.2014.Outward-growth of the Tibetan Plateau during the Cenozoic:A review.Tectonophysics,621:1-43
Wang Y J,Fan W M,Zhang Y H,Peng T P,Chen X Y,Xu Y G.2006.Kinematics and40Ar-39Ar geochronology of the Gaoligong and Chongshan shear systems,western Yunnan,China:Implications for early Oligocene tectonic extrusion of SE Asia.Tectonophysics,418(3-4):235-254
Watson E B,Harrison T M.1983.Zircon saturation revisited:Temperature and composition effects in a variety of crustal magma types.Earth and Planetary Science Letters,64(2):295-304
Whalen J B,Currie K L,Chappell B W.1987.A-type granites:Geochemical characteristics,discrimination and petrogenesis.Contributions to Mineralogy and Petrology,95(4):407-419
Xu Y G,Lan J B,Yang Q J,Huang XL,Qiu H N.2008.Eocene breakoff of the Neo-Tethyan slab as inferred from intraplate-type mafic dykes in the Gaoligong orogenic belt,eastern Tibet.Chemical Geology,255(3-4):439-453
Xu Z Q,Wang Q,Cai Z H,Dong H W,Li H Q,Chen X J,Duan X D,Cao H,Li J,Burg JP.2015.Kinematics of the Tengchong Terrane in SE Tibet from the late Eocene to early Miocene:Insights from coeval mid-crustal detachments and strike-slip shear zones.Tectonophysics,665:127-148
Yamaji A.2003.Slab rollback suggested by latest Miocene to Pliocene forearc stress and migration of volcanic front in southern Kyushu,northern Ryukyu Arc.Tectonophysics,364(1-2):9-24
Yin A,Harrison T M.2000.Geologic evolution of the Himalayan-Tibetan orogen.Annual Review of Earth and Planetary Sciences,28(1):211-280
Zhang B,Zhang J J,Zhong D L.2010.Structure,kinematics and ages of transpression during strain-partitioning in the Chongshan shear zone,western Yunnan,China.Journal of Structural Geology,32(4):445-463
Zhang B,Zhang J J,Chang Z F,Wang X X,Cai F L,Lai Q Z.2012.The Biluoxueshan transpressive deformation zone monitored by synkinematic plutons,around the Eastern Himalayan Syntaxis.Tectonophysics,574-575:158-180
Zhu DC,Wang Q,Zhao ZD,Chung SL,Cawood P A,Niu Y L,Liu SA,Wu FY,Mo XX.2015.Magmatic record of India-Asia collision.Scientific Reports,5:14289
常承法.1985.青藏高原的板块构造.矿物岩石地球化学通报,4(2):56-58
陈珲,李峰,坚润堂,罗思亮,姚巍.2010.云南澜沧老厂花岗斑岩锆石SHRIMP定年及其地质意义.地质学报,84(4):485-491
董方浏,侯增谦,高永丰,曾普胜,蒋成兴.2006.滇西腾冲新生代花岗岩:成因类型与构造意义.岩石学报,22(4):927-937
董美玲,董国臣,莫宣学,朱弟成,聂飞,于峻川,王鹏,罗微.2013.滇西保山地块中-新生代岩浆作用及其构造意义.岩石学报,29(11):3901-3913
高永娟,林仕良,丛峰,邹光富,陈莉,谢韬.2014.滇西梁河地区闪长岩LA-ICP-MS锆石U-Pb年龄,Hf同位素特征及其地质意义.地质通报,33(10):1482-1491
侯可军,李延河,邹天人,曲晓明,石玉若,谢桂青.2008.LA-MC-ICP-MS锆石Hf同位素的分析方法及地质应用.岩石学报,23(10):2595-2604
侯可军,李延河,田有荣.2009.LA-MC-ICP-MS锆石微区原位U-Pb定年技术.矿床地质,28(4):481-492
黄静宁,陈永清,Zhai X M,卢映祥,谢永富,程志中.2011.滇西保山地块双脉地晚始新世过铝质花岗岩:锆石SHRIMP U-Pb定年、地球化学和成因.中国科学:地球科学,41(4):452-467
金志升,黄智龙,朱成明.1997.云南三江地区富碱侵入岩与煌斑岩的同源性.矿物岩石地球化学通报,16(4):222-224
李峰,陈珲,鲁文举,罗思亮.2010.云南澜沧老厂花岗斑岩形成年龄及地质意义.大地构造与成矿学,34(1):84-91
李再会,王立全,林仕良,丛峰,谢韬,邹光富.2012.滇西高黎贡剪切带内花岗质糜棱岩LA-ICP-MS锆石U-Pb年龄及其构造意义.地质通报,31(8):1287-1295
林进展,曹华文,张寿庭,刘瑞萍,肖常先,杨宽.2015.青藏高原东南缘腾冲来利山A型花岗岩地球化学特征、锆石U-Pb定年及其构造意义.大地构造与成矿学,39(5):959-971
沈敢富.1992.酸性岩浆岩成岩成矿机制新探:以“三江”地区为例.矿物岩石地球化学通报,11(2):86-87
唐渊,尹福光,王立全,王冬兵,廖世勇,孙志明,孙洁.2013.滇西崇山剪切带南段左行走滑作用的构造特征及时代约束.岩石学报,29(4):1311-1324
杨帆,李峰,陈珲,肖静珊,赵晓勇.2012.云南澜沧老厂隐伏花岗斑岩体地球化学特征及构造环境.岩石矿物学杂志,31(1):39-49
杨启军,徐义刚,黄小龙,罗震宇,石玉若.2009.滇西腾冲-梁河地区花岗岩的年代学、地球化学及其构造意义.岩石学报,25(5):1092-1104
喻学惠,肖晓牛,杨贵来,莫宣学,曾普胜,王晋璐.2008.滇西″三江″南段几个花岗岩的锆石SHIRMP U-Pb定年及其地质意义.岩石学报,24(2):377-383
云南省地质调查院.2004.1︰25万临沧幅区域地质图及调查报告
邹光富,毛英,邹鑫,林仕良,丛峰,李再会,谢韬,高永娟.2013.滇西芒市江东花岗岩体的锆石U-Pb年龄、地球化学特征及构造意义.地质学报,87(11):1635-1646