新疆地质
新疆地質
신강지질
XINJIANG GEOLOGY
2013年
2期
124-128
,共5页
何峻岭%廖群安%刘跃飞%董文钦
何峻嶺%廖群安%劉躍飛%董文欽
하준령%료군안%류약비%동문흠
哈密%头苏泉%哈尔欣巴%准铝质A型花岗岩%锆石U-Pb年代
哈密%頭囌泉%哈爾訢巴%準鋁質A型花崗巖%鋯石U-Pb年代
합밀%두소천%합이흔파%준려질A형화강암%고석U-Pb년대
Hami%Tousuquan%Haerxinba%Quasi aluminous granites%Zircon U-Pb dating
初步研究表明新疆哈密头苏泉地区哈尔欣巴花岗岩为A型花岗岩.该岩体富硅(SiO2=71.87%~76.80%)和碱(K2O+N2O=7.39%~8.94%),贫铁、锰、镁(FeOt 0.67%~2.04%;MnO 0.03%~0.06%;MgO 0.10%~0.61%),具较高FeOt/MgO比值,A/NKC=0.78~1.02,属准铝质花岗岩石.在微量元素和稀土元素组成上,岩石富Zr,Rb,Ce等不相容元素,亏损Ni,Co,Cr等元素.10000×Ga/Al为3.12~4.1,大于A型花岗岩下限值(2.6).在Zr,Ce,Nb,Y与10000×Ga/Al,及(Nb+Zr+Ce+Y)/(FeOt/MgO)、SiO2/( FeOt/MgO)图解中大多数点都落在A型花岗岩区域.在A1-A2构造环境判别图上显示后造山花岗岩特征.对头苏泉地区哈尔欣巴A型花岗岩的厘定,为研究该区地壳物质组成及构造演化具重要意义.
初步研究錶明新疆哈密頭囌泉地區哈爾訢巴花崗巖為A型花崗巖.該巖體富硅(SiO2=71.87%~76.80%)和堿(K2O+N2O=7.39%~8.94%),貧鐵、錳、鎂(FeOt 0.67%~2.04%;MnO 0.03%~0.06%;MgO 0.10%~0.61%),具較高FeOt/MgO比值,A/NKC=0.78~1.02,屬準鋁質花崗巖石.在微量元素和稀土元素組成上,巖石富Zr,Rb,Ce等不相容元素,虧損Ni,Co,Cr等元素.10000×Ga/Al為3.12~4.1,大于A型花崗巖下限值(2.6).在Zr,Ce,Nb,Y與10000×Ga/Al,及(Nb+Zr+Ce+Y)/(FeOt/MgO)、SiO2/( FeOt/MgO)圖解中大多數點都落在A型花崗巖區域.在A1-A2構造環境判彆圖上顯示後造山花崗巖特徵.對頭囌泉地區哈爾訢巴A型花崗巖的釐定,為研究該區地殼物質組成及構造縯化具重要意義.
초보연구표명신강합밀두소천지구합이흔파화강암위A형화강암.해암체부규(SiO2=71.87%~76.80%)화감(K2O+N2O=7.39%~8.94%),빈철、맹、미(FeOt 0.67%~2.04%;MnO 0.03%~0.06%;MgO 0.10%~0.61%),구교고FeOt/MgO비치,A/NKC=0.78~1.02,속준려질화강암석.재미량원소화희토원소조성상,암석부Zr,Rb,Ce등불상용원소,우손Ni,Co,Cr등원소.10000×Ga/Al위3.12~4.1,대우A형화강암하한치(2.6).재Zr,Ce,Nb,Y여10000×Ga/Al,급(Nb+Zr+Ce+Y)/(FeOt/MgO)、SiO2/( FeOt/MgO)도해중대다수점도락재A형화강암구역.재A1-A2구조배경판별도상현시후조산화강암특정.대두소천지구합이흔파A형화강암적전정,위연구해구지각물질조성급구조연화구중요의의.
This study preliminarily shows that the granites distributed in Haerxinba of Hami area in Xinjiang is defined as A-type granites characterized by enrichment of silicon(SiO2=71.87%~76.80%)and alkali(K2O+N2O=7.39%~8.94%) but short of iron, manganese, and magnesium(FeOt 0.67%~2.04%;MnO 0.03%~0.06%;MgO 0.10%~0.61%)as well as high FeOt/MgO ratio (A/NKC=0.78~1.02), which belongs to quasi aluminous granites. In the view of composition of trace elements and rare-earth elements, this kind of granites has abundant incompatible elements like Zr,Rb,Ce and bar-ren elements like Ni,Co,Cr.The ratio 10000*Ga/Al is that between 3.12 to 4.1, which is larger than the minimal value (2.6) of A-type granite.In graphical analysis, most points of Ze,Ce,Nb,Y,1000* Ga/Al,(Nb+Zr+Ce+Y)/(FeOt/MgO) and SiO2/( FeOt/MgO)are stayed in the area of A-type granite.The A1-A2 tectonic environment discrimination diagram re-veals that those granites show the features of post-orogenic movement granites. The determination of A-type granites in Haerxinba, Tousuquan area has made an important influence on further study of crustal structure and evolution there.
