CAJ | 학술논문

在内蒙古毛登地区发现碎斑熔岩发育，其具有熔岩和熔结凝灰岩的双重结构。毛登碎斑熔岩岩体呈近圆形穹状，可划分出中心相、过渡相和边缘相，不同相带岩石特征明显。LA-ICP-MS锆石U-Pb年龄为139.20Ma±0.73Ma，属早白垩世火山-岩浆活动的产物。岩石富硅、碱，轻稀土元素富集，Eu强烈亏损，富集Rb、Th，亏损Ba、K，与同期流纹岩的地球化学特征相同，研究表明其形成于造山后板内伸展环境。
재내몽고모등지구발현쇄반용암발육，기구유용암화용결응회암적쌍중결구。모등쇄반용암암체정근원형궁상，가화분출중심상、과도상화변연상，불동상대암석특정명현。LA-ICP-MS고석U-Pb년령위139.20Ma±0.73Ma，속조백성세화산-암장활동적산물。암석부규、감，경희토원소부집，Eu강렬우손，부집Rb、Th，우손Ba、K，여동기류문암적지구화학특정상동，연구표명기형성우조산후판내신전배경。
The porphyroclastic lava with the texture of both lava and ignimbrite was found for the first time in Maodeng area of In-ner Mongolia. The Maodeng porphyroclastic lava body,occurring as an oval dome,can be divided into internal facies,transitional facies and external facies. Based on the field geological investigation and the LA-ICP-MS zircon U-Pb age ,the authors hold that it was produced by volcanic and magmatic activities in Early Cretaceous. The rock is characterized by enriched Si ,alkaline and LREE, with relatively strong negative Eu anomaly ,high Rb and Th content and low Ba and K. It resembles the liparite of the same period in geochemical characteristics. It is suggested that the porphyroclastic lava body was formed in an intra-plate anorogenic extensional setting.