CAJ | 학술논문

西准噶尔东部哈拉阿拉特山南麓乌尔禾地区新发现大量中基性岩墙群。岩墙群侵位于下二叠统佳木河组磨拉石建造中，展布方向与达尔布特大断裂延伸方向一致。岩墙群中采集的3个锆石U-Pb年龄样品测年结果分别为（286.3±4）Ma（n=18，MSWD=0.32，95%置信度），（286.5±5.6）Ma（n=10，MSWD=0.3，95%置信度）和（283.6±2）Ma （n=6，MSWD=0.57，95%置信度），误差范围内基本一致，据此确定该岩墙群形成于早二叠乌拉尔世（Cisuralian）亚丁斯克期（Artinskian）。中基性岩墙群具鲜明的与岛弧俯冲作用有关的地化特征，做为西准东部俯冲造山的地质记录，测年结果表明，西准东部的俯冲造山作用明显滞后于西部，整个西准地区俯冲造山作用结束的最终时限为早二叠世晚期。
서준갈이동부합랍아랍특산남록오이화지구신발현대량중기성암장군。암장군침위우하이첩통가목하조마랍석건조중，전포방향여체이포특대단렬연신방향일치。암장군중채집적3개고석U-Pb년령양품측년결과분별위（286.3±4）Ma（n=18，MSWD=0.32，95%치신도），（286.5±5.6）Ma（n=10，MSWD=0.3，95%치신도）화（283.6±2）Ma （n=6，MSWD=0.57，95%치신도），오차범위내기본일치，거차학정해암장군형성우조이첩오랍이세（Cisuralian）아정사극기（Artinskian）。중기성암장군구선명적여도호부충작용유관적지화특정，주위서준동부부충조산적지질기록，측년결과표명，서준동부적부충조산작용명현체후우서부，정개서준지구부충조산작용결속적최종시한위조이첩세만기。
Intermediate to mafic dyke swarms are newly discoveried in Urho area,the south of Hala’alat mountain which is located in the east of West Junggar.The dyke swarms intruded the Permian Jiamuhemolasse formation.The near-ly NE—SW-trending dyke swarms are parallel to Darbut Fault. Three samples for LA-ICP-MS zircon U-Pb dating from the dyke swarms yielded an age of (286.3 ± 4) Ma(n=18, MSWD=0.32, 95% confidence), (286.5 ± 5.6) Ma(n=10, MSWD=0.3, 95%confidence)and (283.6±2) Ma(n=6, MSWD=0.57, 95%confidence).The fact that the same in error range confirms the dyke swarms belong to the Cisuralian Epoch of Early Permian.The dyke swarms with characteristics of island-arc zone show that subduction in the east of West Junggar was posterior to the subduction in the west and mid-dle of West Junggar.The final end of the subduction in West Junggar was in late Early Permian,rather than early Carbon-iferous previously thought.