The internal mineral separates and whole - rock sm - nd isochron age for gabbro dikes from the dangqiong ophiolite is 373 ? 8ma , inferring a magmatic activity during late devonian , which end ( t ) = + 3 . 3 suggests that its tectonic setting was probably oceanic island 其nd ( t ) = + 3 . 3 ，认为其时形成环境为洋岛，可能代表了新特提斯蛇绿岩形成时所携带的古老洋壳。
Guided by theory and method of unit - superunit mapping in the granite area , study the lithology , lithochemistry , trace elements , and rare earth elements , er . of the wuzengsu gabbro body , and subdivide the body into four units 摘要借鉴花岗岩区单元超单元填图理论方法，通过对乌增苏辉长岩体岩石学、岩石化学、微量元素、稀土元素等特征的研究，将岩体划分为四个单元。
The lithologies of intrusive rocks were re - determined , for example , the rock previously named as diorite in southern area was renamed as gabbro , and the dike rock distributed along nnw as spessartite which was related to formation of the zhulazaga gold deposit to some extent 对矿区各类侵入岩重新厘定了它们的岩性特征，如矿区东南部原闪长岩重新确定为辉长岩，确定nnw向分布的脉岩为闪斜煌斑岩，且认为后者和朱拉扎嗄金矿的形成有一定的关系。
It agrees with the fact that the gabbro is intruded by late ordovician granitic pluton . the pre - sinian basement strata exposed in the north kunlun massif are later archean - neoproterozoic milan group , changcheng system kaqiang group , jixian system liushui formation and qingbaikou system sulu formation 被蛇绿岩所分隔的昆北地块上出露的前震旦纪基底地层为：晚太古代-新元古代米兰岩群，长城系卡羌岩群，蓟县系流水岩组和青白口系丝路岩组。
Based on an analysis of geochemical characteristics of rocks and trace elements as well as rare earth elements , this paper holds that they are products of crystallization differentiation of the same magma , that the major ore resource of this area is copper , and that gabbro - diabase is the main ore - bearing horizon 通过对岩石化学特徵和微量元素、稀土元素地球化学特徵的剖析，表明其是同一岩浆结晶分异的产物，本区主要矿产应为铜，辉长辉绿岩是主要的含矿层位。
The mafic dikes also formed by the partial melting of enriched mantle , include gabbro , diabase ( distributing mainly in luxi ) and lamprophyres ( camptovogesite , odinite and hornblende lamprophyres ) ( mainly in ludong ) . for all the rocks , crustal contamination was absent when magma emplaced . 2 基性脉岩主要包括辉长岩、辉绿岩(主要分布在鲁西地区)和煌斑岩(以斜闪煌斑岩为主，同时含部分拉辉煌斑岩和角闪煌斑岩) (主要分布在鲁东地区) ，都为富集岩石圈地幔部分熔融的产物。
The results of combined internal mineral separates and whole - rock sm - nd isochron age for gabbro dikes from : luobusha , angren and xiubugabu in yarlung zangpo ophilite zone are 177ma , 166ma and 173ma respectively . the 4lar - 39ar step heating spectra of rikangba ophiolite suggest that its formation age is also isoma . it indicates that there was a stronger regionally inagmatism during middle - early jurassic , and the time of i75ma was the main period of the magmatic event of yarlung zangpo ophilite 对邬郁盆地嘎扎村组火山岩剖面的年代学研究表明，该区后碰撞期火山岩的~ ( 40 ) ar - ~ ( 39 ) ar年龄为12 ? 14ma ，侵入其中的花岗岩脉的~ ( 40 ) ar - ~ ( 39 ) ar年龄为10 . 84ma ，与冈底斯西段前人研究资料对比，认为冈底斯带后碰撞火山岩时代有自西向东逐渐年轻的趋势。
Geochronological , geochemical and sr - nd isotopic data are reported for the alkaline igneous rocks ( syenites and zhaibei aluminous a - type granite ) and chebu gabbro in southern jiangxi province . shrimp zircon u - pb dating results indicate that the quannan syenite , zhaibei a - type granite and chebu gabbro formed during the early yanshanian period 对赣南燕山早期的富碱火成岩(正长岩和寨背铝质a型花岗岩)和车步辉长岩进行了详细的年代学、元素和sr - nd地球化学研究。
We deduce that it is a relic old crust that was brought upwards during the formation of neo - tethyan ophiolite . the step heating 40ar - ' 9ar spectra show that during 100ma , luobusha ophiolite suffered intensely alternation , which affected distinctly the k - ar system ; during 771ma some basalt formed in the country rock of xiubugabu ophiolite ; during 55ma , the pillow basalt of rikangba ophiolite affected by a strong thermal event ; all the variety of ages illustrates possible impacts of the subduction - collision between india and eurasia . through dissecting mainly the gabbro of luobusa ophiolite and studying the 40ar / 39ar ~ ( 40 ) ar ~ ( 39 ) ar阶段升温年龄图谱显示， 100ma左右罗布莎岩体经历了较强的后期蚀变作用，对其k ? ar体系造成明显影响； 77 1ma休古嘎布岩体围岩中形成玄武质火山集块岩； 55ma日康巴岩体岩石枕状玄武岩受到较强热事件影响；这些~ ( 40 ) ar - ~ ( 39 ) ar年龄上的变化显示了印度板块与欧亚板块俯冲?碰撞对该区的强烈影响。
The alkaline basalts in southern hunan are suggested to have formed by small degrees of decompression melting of the asthenosphere mantle during the initial extension . the transitional ( the chebu gabbro ) and tholeiitic basaltic magmas were generated by relatively larger degrees of partial melting of the mantle 在裂谷初期，软流圈地幔的小比例部分熔融形成碱性玄武岩(湘南) ，在裂谷拉张作用比较强、地幔部分熔融比例比较大时形成赣南和湘南的过渡型(车步辉长岩)及拉斑质玄武岩。
