秦万宜, 陈汉宗, 高承连. 湖北省大别山地区周家湾岩体的特征及其时代[J]. 地质通报, 1985, (3): 125-132.
    引用本文: 秦万宜, 陈汉宗, 高承连. 湖北省大别山地区周家湾岩体的特征及其时代[J]. 地质通报, 1985, (3): 125-132.
    QIN Wan-yi, CHEN Han-zong, GAO Cheng-lian. THE CHARACTERISTICS AND AGE OF THE ZHOUJIAWAN ROCK MASS IN THE DABIE MOUNTAINS AREA,HUBEI PROVINCE[J]. Geological Bulletin of China, 1985, (3): 125-132.
    Citation: QIN Wan-yi, CHEN Han-zong, GAO Cheng-lian. THE CHARACTERISTICS AND AGE OF THE ZHOUJIAWAN ROCK MASS IN THE DABIE MOUNTAINS AREA,HUBEI PROVINCE[J]. Geological Bulletin of China, 1985, (3): 125-132.

    湖北省大别山地区周家湾岩体的特征及其时代

    THE CHARACTERISTICS AND AGE OF THE ZHOUJIAWAN ROCK MASS IN THE DABIE MOUNTAINS AREA,HUBEI PROVINCE

    • 摘要: 周家湾片麻状花岗岩体位于湖北省大悟县大悟山南麓。岩体规模不大,但其所处地质构造条件复杂,附近又发现多种有色金属及非金属矿产,故近几年来为我省广大地质工作者所重视,在该区投入了较多的地质工作。由于工作深度不够,长期以来对岩体的时代及成因一直存在着不同的意见。一九七三年一比二十万黄陂幅地质报告将该岩体定为燕山早期花岗岩侵入体;一九七九年一比五万小河镇幅及一九八一年松林岗幅地质报告则又将其

       

      Abstract: The Zhoujiawan gneissose granite mass in the Dabie Mountains area, Hubei province, was in the past wrongly determined to be an early Yanshanian intrusion. This paper presents the authors’ recent preliminary research results in respects of the occurrence characteristics, petrochemical composition and isotopic age of this rock mass, and points out that the Zhoujiawan rock mass is actually a Proterozoic intrusion. It has the following characteristics: the rocks belong to the cale-alkaline series, the gneissose structure is well developed, part of plagioclase exhibits a distinct phenomenon of potassium metasomatism, the mafic content and REE abundance are slightly high, and the accessory mineral zircon is almost of a single colour-light purplish-red. Nine zircon samples collected from the rock mass yield an average U-Pb apparent age of 1973m. y. and a Pb-Pb isochron age of 1973±89 m.y.; the upper intercept age on the Witherill concordia plot is 2032±173 m.y. The rock mass cuts the metamorphic rock series of the Hongan Group (early Proterozoic) but is in turn unconformably overlain by the middle-upper Proterozoic dolomite marble, so the time of its intrusion should be equivalent to the Wutai Stage. The Zhoujiawan rock mass may be regarded as the representive of the Precambrian granitoids in the Dabie Mountains area, and its characteristics are obviously different from those of the granitoid intrusions formed since the Paleozoic.

       

    /

    返回文章
    返回