CAJ | 학술논문

分布在锡林浩特-达青牧场一带的锡林郭勒杂岩主要由变质表壳岩、变质基性-超基性岩、花岗质片麻岩等组成，其中部分为前寒武纪地层和岩石，构成前寒武纪微陆块。本文对锡林浩特西部呼热木台敖包和白音陶勒盖一带锡林郭勒杂岩中副变质岩锆石LA-MC-ICP-MS U-Pb年代学进行了研究，原岩碎屑锆石年龄介于403~3077 Ma，其中206Pb/238U最年轻一组的年龄在403~420 Ma，代表了该变质岩原岩的沉积下限。结合其变质时代（337 Ma）及被早石炭世-晚石炭世早期岛弧侵入岩侵入的事实，该套地层主要形成在早泥盆世中期-早石炭世早期，不是前寒武纪地层。其原岩主要为一套正常沉积碎屑岩，缺少火山岩，不具弧前沉积建造特征。它是沉积在前寒武纪锡林浩特微陆块之上的一套地层，为早古生代造山后伸展背景下晚古生代贺根山洋盆南缘初始的沉积记录。
분포재석림호특-체청목장일대적석림곽륵잡암주요유변질표각암、변질기성-초기성암、화강질편마암등조성，기중부분위전한무기지층화암석，구성전한무기미륙괴。본문대석림호특서부호열목태오포화백음도륵개일대석림곽륵잡암중부변질암고석LA-MC-ICP-MS U-Pb년대학진행료연구，원암쇄설고석년령개우403~3077 Ma，기중206Pb/238U최년경일조적년령재403~420 Ma，대표료해변질암원암적침적하한。결합기변질시대（337 Ma）급피조석탄세-만석탄세조기도호침입암침입적사실，해투지층주요형성재조니분세중기-조석탄세조기，불시전한무기지층。기원암주요위일투정상침적쇄설암，결소화산암，불구호전침적건조특정。타시침적재전한무기석림호특미륙괴지상적일투지층，위조고생대조산후신전배경하만고생대하근산양분남연초시적침적기록。
Xilin Gol complex occurs in Xilinhot-Daqingmuchang area and is composed of metamorphic supracrustal rocks, metamorphic basic-ultrabasic rocks and granitic gneiss, with some of them being Precambrian in age and constituting Precambrian block. Recent dating of the LA-MC-ICPMS U-Pb zircons from parametamorphic rocks of Xilin Gol complex in Huremutaiaobao and Baiyintaolegai area yieled ages of detrital zircons ranging from 403Ma to 3077 Ma with a group of 206Pb/238U ages in the youngest strata between 403 and 420 Ma, probably representing the lower limited age of the sedimentary rock. Combined with 337 Ma metamorphic age of the parametamorphic rocks which were emplaced by arc intrusive rocks of Early Carboniferous-early Late Carboniferous, the authors hold that the parametamorphic rocks were formed in middle Early Devonian-early Early Carboniferous, and their protolith belonged to normal sedimentary rocks without being subjected to volcanic activity, and hence it was not characterized by forearc deposition formation. Therefore, it comprised a set of strata deposited on Precambrian Xilinhot micro-block, representing initial deposition of the southern margin of Late Paleozoic Hegenshan Ocean basin with extension after Early Paleozoic collision orogenesis.