%0 Journal Article
%T Sr-rich apatite from the Dangzishan leucitite-ijolite xenoliths (Heilongjiang Province): Mineralogy and mantle-fluid metasomatism<br>
%A WenLan Zhang
%A JiAn Shao
%A RuCheng Wang
%A XiSheng Xu
%A XuDong Che
%A YueHeng Yang
%A <br>
%J 科学通报(英文版)
%D 2011
%I 
%X Abundant apatite grains with elevated SrO content were found in leucitite-ijolite xenoliths in the Dangzi Mountain, Heilongjiang Province. Morphological and mineralogical associations, and compositional analysis of the Sr-rich apatite, were carried out using an electron microprobe. Two principal types of apatite were distinguished. One type occurs as short-prismatic crystals with Sr-rich rims, while another type with acicular or finely columnar shapes constitutes Sr-rich apatite element maps and systematic quantitative analysis of apatite revealed great variations in SrO content (0.42%-26.79%). The calculated structural formula of the measured Sr-rich apatite is: (Ca3.15-4.963Sr0.019-1.510Ba0.00-0.030Na0.006-0.108REE0.106-0.153) (P2.84-3.028Si0.009–0.094)O12(F0.675-1.079, Cl0.000-0.256, OH0.084-0.297). Mineralogical textures of apatite implied a replacement mechanism for the Sr-rich apatite. Sr-rich rims of apatite are suggested to have formed after metasomatism (isomorphic replacement) of early fluorapatite in a Sr-, light rare-earth elements (LREE), lithophile light elements (LILE)- and volatile-rich residual melt during late magmatism. However, the acicular apatite probably directly crystallized from a Sr-rich residual melt.The Sr-Nd isotopic composition of the apatite was distinctive from that of leucitite-ijolite and its host rock. These differences, combined with mineralogical features of apatite, imply that Sr-LREE-LILE-volatile-rich components in the residual melt were derived from deep in the asthenosphere, and subsequently were enriched at a late stage in magma evolution.
%K leucitite-ijolite xenolith
%K Sr-rich apatite
%K isomorphic replacement
%K depleted-mantle fluids
%K Dangzi Mountain
%K Heilongjiang Province<br>
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=01BA20E8BA813E1908F3698710BBFEFEE816345F465FEBA5&cid=96E6E851B5104576C2DD9FC1FBCB69EF&jid=DD6615BC9D2CFCE0B6F945E8D5314523&aid=C10A00BA5D27FF30A99F668A3EF2ED11&yid=9377ED8094509821&vid=014B591DF029732F&iid=CA4FD0336C81A37A&sid=8E6AB9C3EBAAE921&eid=E84BBBDDD74F497C&journal_id=1001-6538&journal_name=科学通报(英文版)&referenced_num=1&reference_num=27