豫皖交界“梅山群”的古构造环境研究及其意义

“梅山群”是豫皖交界地段变质程度与佛子岭群、石炭系不同的变质岩系。它主要由斜长角闪岩、变粒岩、浅粒岩、云英片岩、角闪片岩、黑云片岩、大理岩和辉石岩等组成，在区域上可以和商城群歪庙组对比，形成时代为早古生代．对“梅山群”的岩石化学研究表明，其形成的古构造环境可能为弧后盆地。笔者认为早古生代，南北大陆板块构造的碰撞以华北板块仰冲、扬子板块俯冲为特征，大别造山带古缝合带的位置应在“梅山群”分布区域的南侧。

STUDY ON PALEOTECTONIC ENVIRONMENT OF MEISHAN GROUP ON ANHUI-HENAN BORDER AND ITS IMPLICATIONS

he Meishan Group which is different from the Foilling Group and Carboniferous by their metamorphism distributes at the northern foot of Dabie mountains on the AnhuiHenan border. It consists of amphibolite granulitite, Leucogranulitite, quartz schist, amphibole schist, biotite schist and marble. It Can be Compared with the Waimiao Formation of Shangcheng Group regionally and is Early Paleozoic in age. The study of petrochemical of the Meishan Group indicates that the paleotectonic environment in its distribution area is back-arc basin. According to this opinion, the Early Paleozoic collision between "North China" and "South China" is characterized by the North China plate obducting and the Yangtze subducting. The paleosuture between "North China "and "South China" is located in the southern part of the Meishan Group distributing area.