现代地质Issue(4)：884-895,12.
扬子陆核古元古代A型花岗岩的年代学与地球化学研究及其构造意义
Geochronological and Geochemical Study for the Paleoproterozoic A-type Granite in the Nucleus of the Yangtze Craton and Its Tectonic Implication
摘要
Abstract
This study carries out systematical geochemical and geochronological investigations on the Quanyi-shang granitic pluton intruding into the Kongling Complex,and discusses the petrogenesis and Paleoproterozoic evolution of the nucleus of the Yangtze craton.The zircon LA-ICP-MS U-Pb dating shows that crystallization age of the granite is (1 822 ±44)Ma,hence a typical product of Paleoproterozoic magmatism of the Yangtze conti-nental interior.The geochemical research illustrates a depletion of Al,Mg and enrichment of Rb,Th,as well as negative anomalies of high field strength elements (HFSE)and Eu,Ba and Sr.High Ga/Al ratio and Zr+Nb+Ce+Y content and relatively high calculated zircon saturation temperature (>862 ℃),combined with other geochemical features,indicate that the Quanyishang granitic pluton is aluminous A-type granite.The εNd (t) value varies between -12.4 to -10.3 and the correspondent two-stage Nd isotopic modal ages range from 3.3 to 3.2 Ga.These characteristics imply that the granite may have formed by partial melting of ancient felsic crus-tal material in the nucleus of the Yangtze craton under a low-pressure,high-temperature condition at a post-col-lisional extensional tectonic setting.Combined with the documented work,it may have relationship with the re-gional tectonic transition from collisional extrusion to extention in a post-collisional setting during the period from 2.0 to 1.9 Ga.The Paleoproterozoic tectonic magmatic events of the Yangtze craton is consistent with the global 2.1 -1.8 Ga collisional orogeny to breakup events related to the evolution of Columbia supercontinent,indica-ting that the nucleus of the Yangtze craton may have been an important part of Columbia supercontinent.关键词
扬子陆核/古元古代/圈椅!花岗岩/A型花岗岩/构造意义Key words
nucleus of the Yangtze craton/Paleoproterozoic/Quanyishang granite/A-type granite/tectonic implication分类
天文与地球科学引用本文复制引用
邱啸飞,杨红梅,卢山松,谭娟娟,蔡应雄..扬子陆核古元古代A型花岗岩的年代学与地球化学研究及其构造意义[J].现代地质,2015,(4):884-895,12.基金项目
国家自然科学基金青年基金项目（41303026）；中国地质调查局地质调查项目（1212011121102，1212011220512）；中国地质调查局百名青年地质英才培养计划。 （）
