摘要
胶东蓬家夼金矿区钾玄质煌斑岩的元素地球化学研究表明，其成分上具有高碱富钾、高铝低钛、大离子亲石元素和轻稀土元素强烈富集及相容元素（Cr、Co、Ni）明显亏损等特点。钾玄质岩浆是由富集地幔通过批式部分熔融作用产生的，而且其原始岩浆在上升和侵位过程中存在橄榄石和辉石等矿物相的分离结晶，并伴有陆壳物质的混染。本区煌斑岩具有与陆弧有关的钾质火成岩类似的地球化学特征，可能与燕山期伊泽奈崎洋向中国东部大陆下的俯冲作用有密切的成因联系。
The shoshontic lamprophyres in the Pengjiakuang gold district are characterized by high alkaline, high K_2O / Na_2O ratios, low TiO_2, high and variable Al_2O_3, a strong enrichment in LILE and LREE, and distinct depletion in comparable element (Cr, Co and Ni). These geochemical characteristics clearly indicate that they were derived from the batch partial melting of the enriched mange and fractional crystallization of olivine and clinopyroxene. Based on the geochemical discrimination diagrams proposed by Muller (1993), the shoshonitic lamprophyres were formed in the continental are setting,and could be related to the subduction of Izanaqi oceanic plate beneath the continent of East China in the Yanshanian Period.
出处
《地球化学》
CAS
CSCD
北大核心
1998年第1期91-100,共10页
Geochimica
基金
国家和广东省博士后科学基金
关键词
钾玄质煌斑岩
元素地球化学
煌斑岩
金矿床
shoshonictic lamprophyres, element geochemistry, Shandong Province
