滇西高黎贡山变质带变质深成岩特征及时代
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摘要
高黎贡山变质岩带中(腾冲大蒿坪地区),原划归古元古代高黎贡山岩群中广泛存在的变质深成岩类,原岩实际为早白垩世(163.5±5.7Ma)花岗闪长岩和晚白垩世(74.0±2.0Ma)二长花岗岩类,属变质的燕山期深成侵入岩,可划分为扬飞水角闪黑云花岗闪长质片麻岩、芹菜塘花岗片麻岩两个变质地体单元。早白垩世花岗闪长岩形成于造山前期同碰撞火山弧环境;晚白垩世二长花岗岩侵入岩形成于造山前期碰撞造山环境,并沿断裂带强烈侵位。原岩经喜马拉雅早期韧性剪切带动力变质,变质强度达高绿片岩相或低角闪岩相,形成花岗质片麻岩类,喜马拉雅中期叠加脆韧性动力变质作用。
The widely developed metamorphic plutonic rocks in the metamorphic zone of the Gaoligong Mountains were allocated to Gaoligongshan Group of Paleoproterozoic previously,however,the original rocks of which were granodiorite of Early Crataceous(163.5±5.7 Ma) and adamellite of Late Crataceous(74.0±2.0Ma) .They belong to metamorphic plutonic intrusion rocks of Yanshanian age,which could be divided into two metamorphic terrane units,being named the Yangfeishui hornblende-biotite granodiorite gneiss and the Qincaitang granite gneiss.The granodiorite rocks of Early Crataceous were formed in the environment of syn-collision volcanic arc of pre-orogenic phase,while the adamellite intrusion rocks of Late Crataceous were formed in the environment of collisional orogeny of pre-orogenic phase,with intense emplacement along the fault belt.The original rocks were undergone the dynamic metamorphism of ductile shear belt of early Himalayan period with the metamorphic intensity of high greenschist facies or low amphibolite facies,which attributed to the formation of granitic gneiss and the superimposed brittle-ductile dynamic metamorphism of the middle Himalayan period.
The widely developed metamorphic plutonic rocks in the metamorphic zone of the Gaoligong Mountains were allocated to Gaoligongshan Group of Paleoproterozoic previously,however,the original rocks of which were granodiorite of Early Crataceous(163.5±5.7 Ma) and adamellite of Late Crataceous(74.0±2.0Ma) .They belong to metamorphic plutonic intrusion rocks of Yanshanian age,which could be divided into two metamorphic terrane units,being named the Yangfeishui hornblende-biotite granodiorite gneiss and the Qincaitang granite gneiss.The granodiorite rocks of Early Crataceous were formed in the environment of syn-collision volcanic arc of pre-orogenic phase,while the adamellite intrusion rocks of Late Crataceous were formed in the environment of collisional orogeny of pre-orogenic phase,with intense emplacement along the fault belt.The original rocks were undergone the dynamic metamorphism of ductile shear belt of early Himalayan period with the metamorphic intensity of high greenschist facies or low amphibolite facies,which attributed to the formation of granitic gneiss and the superimposed brittle-ductile dynamic metamorphism of the middle Himalayan period.
引文
丁林.1991.滇西高黎贡山南段构造变形特征及演化历史讨论.北京:中国科学院地质地球物理研究所,硕士论文:1～156.
云南省地质调查院.2003.1︰5万曲石街、打苴街、大董街幅区域地质调查报告.
樊春,王二七.2004.滇西高黎贡山左行剪切带构造形迹的发现及其大地构造意义.自然科学进展,14(10):1189～1193.
简平,刘敦一,孙晓猛.2003.滇川西部金沙江石炭纪蛇绿岩SHRIMP测年:古特提斯洋盆演化的同位素年代学制约.地质学报,77(2):217～228.
吴小奇,刘德良,李振生,杨强.2003.滇西主高黎贡山韧性剪切带糜棱岩形成时限初探.大地构造与成矿学,30(2):136～141.
云南省地质矿产局.1990.云南区域地质志.北京:地质出版社,18～22,590～592.
钟大赉.1998.滇川西部古特提斯造山带.北京:科学出版社,189～193.
Boynton W V.1984.Geochemistry of the rare-earth elements:meteorite studies.In:Henderson Press.Rare earth element geochemistry.Amsterdam:Elsevier,1984:1～510.
Compston W,Williams I S,Kirschvink J L,Zhang Z C,Guogan M A.1992.Zircon U-Pb ages for the early Cambrian time-scale.Journal of the Geological Society,London,149:171～184.
Ludwig K R.1999.Using Isoplot/EX,version2:A geolocronolgical toolkit for Microsoft Excel.Berkeley:Berkeley Geochronological Center special Publication,1～47.
Ludwig K R.2001.Squid1.02:A user manual.Berkeley:Berkeley Geochronological Center Special Publication,2～19.
McDonough W F and Sun S S.1985.Isotopic and geochemical systematics in Tertiary-Recent basalts from southeastern Australia and implication for the sub-continental lithosphere,Geochim.Cosmochim.Acta,49:2051～2067.
Williams I S and Claesson S.1987.Isotope evidence for the Precambrian paovince and Caledonian metamorphism of hige grade paragneiss form the Seve Nappes.Seandinavian Caledonides,Ⅱ.Ionmicroporbe zircon U-Th-Pb.Contrib.Mineral.Petrol.,97:205～217.
云南省地质调查院.2003.1︰5万曲石街、打苴街、大董街幅区域地质调查报告.
樊春,王二七.2004.滇西高黎贡山左行剪切带构造形迹的发现及其大地构造意义.自然科学进展,14(10):1189～1193.
简平,刘敦一,孙晓猛.2003.滇川西部金沙江石炭纪蛇绿岩SHRIMP测年:古特提斯洋盆演化的同位素年代学制约.地质学报,77(2):217～228.
吴小奇,刘德良,李振生,杨强.2003.滇西主高黎贡山韧性剪切带糜棱岩形成时限初探.大地构造与成矿学,30(2):136～141.
云南省地质矿产局.1990.云南区域地质志.北京:地质出版社,18～22,590～592.
钟大赉.1998.滇川西部古特提斯造山带.北京:科学出版社,189～193.
Boynton W V.1984.Geochemistry of the rare-earth elements:meteorite studies.In:Henderson Press.Rare earth element geochemistry.Amsterdam:Elsevier,1984:1～510.
Compston W,Williams I S,Kirschvink J L,Zhang Z C,Guogan M A.1992.Zircon U-Pb ages for the early Cambrian time-scale.Journal of the Geological Society,London,149:171～184.
Ludwig K R.1999.Using Isoplot/EX,version2:A geolocronolgical toolkit for Microsoft Excel.Berkeley:Berkeley Geochronological Center special Publication,1～47.
Ludwig K R.2001.Squid1.02:A user manual.Berkeley:Berkeley Geochronological Center Special Publication,2～19.
McDonough W F and Sun S S.1985.Isotopic and geochemical systematics in Tertiary-Recent basalts from southeastern Australia and implication for the sub-continental lithosphere,Geochim.Cosmochim.Acta,49:2051～2067.
Williams I S and Claesson S.1987.Isotope evidence for the Precambrian paovince and Caledonian metamorphism of hige grade paragneiss form the Seve Nappes.Seandinavian Caledonides,Ⅱ.Ionmicroporbe zircon U-Th-Pb.Contrib.Mineral.Petrol.,97:205～217.