赣东北铁砂街变质混杂岩块的同位素年代

NEW RECOGNITION ON THE ISOTPIC GEOCHRONOLOGY OF THE "TIESHAJIE GROUP" IN THE SOUTHERN PART OF NORTHEASTEPN JIANGXI

赣东北南部的中浅变质岩一直被作为晚元古代地层,并称之为“铁砂街群”。本文根据同位素定年工作、结合野外地质调查和区域构造分析,认为“铁砂街群”不是地层单位,而是晚元古代形成的混杂岩。

The isotopic geochronological study of the 'Tieshajie Group' indicates that this group is melanges formed in the Late Proterozoic, in which Middle Proterozoic blocks are contained, So it Should not be regarded as a stratigraphic unit.