%0 Journal Article
%T Geochemistry and origin of Late Cretaceous (~90Ma) ore-bearing porphyry of Balazha in mid-northern Lhasa terrane, Tibet<br>拉萨地块中北部晚白垩世(约90Ma)拔拉扎含矿斑岩地球化学特征及其成因
%A YU HongXi
%A CHEN JianLin
%A XU JiFeng
%A WANG BaoDi
%A WU JianBin
%A LIANG HuaYing
%A <br>余红霞
%A 陈建林
%A 许继峰
%A 王保弟
%A 邬建斌
%A 梁华英
%J 岩石学报
%D 2011
%I 
%X The ore-bearing porphyry of Balazha in mid-northern Lhasa terrane, with a forming age of 90~88Ma, shows some typical geochemical characteristics of an adakite, such as high SiO2 (>69%), Al2O3(15.89% in average), Sr (354×10-6 in average), but low Y (12.97×10-6 in average), Yb (0.95×10-6 in average) contents, and strongly fractionation between LREE and HREE ((La/Yb)N=19.8 in average). Meanwhile, it is of relatively higher Mg# (65 in average), Cr (107×10-6 in average) and Ni (13×10-6 in average). These geochemical features, combined with other characteristics of Late Cretaceous lavas in mid-northern Lhasa terrane, indicate that they did not result from melting of young oceanic crust, assimilation and fractional crystallization, or from either underplated or thickened continental crust. Instead, they were possibly derived from partial melting of delaminated lower continental crust. On the other hand, they are also likely to the result of partial melting of crust-mantle material, triggered by slab break-off of south-dipping subduction of Slainajap ocean or Bangong Co-Nujiang ocean.
%K Late Cretaceous
%K Balazha
%K Ore-bearing porphyry
%K Geochemistry
%K Lhasa terrane<br>晚白垩世
%K 拨拉扎
%K 含矿斑岩
%K 地球化学
%K 拉萨地块
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=E62459D214FD64A3C8082E4ED1ABABED5711027BBBDDD35B&cid=621CF755B1A341E5&jid=2013B5467E3054B1614CEC199353FCED&aid=8C6F2BFE80788BD11408B74BC8996B3B&yid=9377ED8094509821&vid=DB817633AA4F79B9&iid=DF92D298D3FF1E6E&sid=9377ED8094509821&eid=885CEFEC57DA488F&journal_id=1000-0569&journal_name=岩石学报&referenced_num=1&reference_num=33