大地构造与成矿学
大地構造與成礦學
대지구조여성광학
GETECTONICA ET METALLOGENIA
2010年
1期
133-138
,共6页
杨高学%李永军%司国辉%吴宏恩%金朝%张永智
楊高學%李永軍%司國輝%吳宏恩%金朝%張永智
양고학%리영군%사국휘%오굉은%금조%장영지
锆石LA-ICPMS U-Pb年龄%含锡黑云母正长花岗岩%贝勒库都克%卡拉麦里%东准噶尔
鋯石LA-ICPMS U-Pb年齡%含錫黑雲母正長花崗巖%貝勒庫都剋%卡拉麥裏%東準噶爾
고석LA-ICPMS U-Pb년령%함석흑운모정장화강암%패륵고도극%잡랍맥리%동준갈이
zircon LA-ICPMS U-Pb dating%biotite syenite granite%tin deposit%Belekuduke%Kalamaili%East Junggar
新疆东准噶尔卡拉麦里地区是一个重要的锡成矿带,分布有多种类型的花岗岩.贝勒库都克岩体位于卡拉麦里锡成矿带中部,由含锡正长花岗岩和黑云母二长花岗岩组成.本文对贝勒库都克岩体岩相学和含锡黑云母正长花岗岩的锆石LA-ICPMS U-Pb定年研究,结果表明所有锆石颗粒浅黄色-无色透明,呈正方双锥状、钮柱状及半截锥状自形晶体,且发育规则的韵律环带,具有较高的Th/U比值(范围在0.32~0.47),属于典型岩浆成因锆石.获得贝勒库都克岩体侵位结晶年龄为283±2Ma(n=8, MSWD=0.14),时代属于早二叠世,这与东准噶尔后碰撞深成岩浆活动的范围(330~265Ma)相吻合.为建立准噶尔地区构造格架和恢复岩浆演化事件提供了最有力的证据, 同时具有一定的找矿意义.
新疆東準噶爾卡拉麥裏地區是一箇重要的錫成礦帶,分佈有多種類型的花崗巖.貝勒庫都剋巖體位于卡拉麥裏錫成礦帶中部,由含錫正長花崗巖和黑雲母二長花崗巖組成.本文對貝勒庫都剋巖體巖相學和含錫黑雲母正長花崗巖的鋯石LA-ICPMS U-Pb定年研究,結果錶明所有鋯石顆粒淺黃色-無色透明,呈正方雙錐狀、鈕柱狀及半截錐狀自形晶體,且髮育規則的韻律環帶,具有較高的Th/U比值(範圍在0.32~0.47),屬于典型巖漿成因鋯石.穫得貝勒庫都剋巖體侵位結晶年齡為283±2Ma(n=8, MSWD=0.14),時代屬于早二疊世,這與東準噶爾後踫撞深成巖漿活動的範圍(330~265Ma)相吻閤.為建立準噶爾地區構造格架和恢複巖漿縯化事件提供瞭最有力的證據, 同時具有一定的找礦意義.
신강동준갈이잡랍맥리지구시일개중요적석성광대,분포유다충류형적화강암.패륵고도극암체위우잡랍맥리석성광대중부,유함석정장화강암화흑운모이장화강암조성.본문대패륵고도극암체암상학화함석흑운모정장화강암적고석LA-ICPMS U-Pb정년연구,결과표명소유고석과립천황색-무색투명,정정방쌍추상、뉴주상급반절추상자형정체,차발육규칙적운률배대,구유교고적Th/U비치(범위재0.32~0.47),속우전형암장성인고석.획득패륵고도극암체침위결정년령위283±2Ma(n=8, MSWD=0.14),시대속우조이첩세,저여동준갈이후팽당심성암장활동적범위(330~265Ma)상문합.위건립준갈이지구구조격가화회복암장연화사건제공료최유력적증거, 동시구유일정적조광의의.
Several types of granites are distributed in the Kalamaili area of East Junggar, Xinjiang, which constitutes an important tin metallogenic zone. The Belekuduke granitiod is situated in the centre of the tin metallogenic zone, which consists of biotite syenite granites and biotite monzogranites. On the basis of the preliminary petrological study, the ore-hosting biotite syenite granite of the Belekuduke intrusion is dated by the zircon LA-ICPMS U-Pb method. The zircon grains are of typical magmatic origin, characterized by light yellow-colorless transparent, a square bipyramid, button cylindrical and half cone-shaped crystals, and regular metric zone. The zircon LA-ICPMS U-Pb dating with 283±2Ma (n=8,MSWD=0.14, Th/U ratios of 0.32~0.47) represents the emplacement age of the ore-hosting biotite syenite granite, the time belongs to the Early Permian, which coincides with the period of 330~265Ma, an indicative of the hypogene magma moving of post-collision in East Junggar. The LA-ICPMS U-Pb zircon age from the ore-hosting biotite syenite granite takes an evidence for rebuilding tectonic framework and recovering magma evolution, and has the implication for finding tin deposits in the Kalamaili area of East Junggar, Xinjiang.