中文摘要：

新疆且末县几克里阔勒镁铁—超镁铁岩体位于塔里木板块南缘活动带之喀拉米兰晚古生代沟弧系中段北侧,侵入下石炭统满达拉恰普组第三段海相碎屑岩、碳酸盐岩及中酸性火山岩建造中.主要岩石类型有纯橄岩、二辉橄榄岩、单辉橄榄岩、含长橄榄二辉岩、二辉岩、橄榄辉长岩、淡色辉长岩.岩石地球化学及岩相学特征表明：岩浆作用早期,分离结晶作用主导了岩浆演化过程和岩体形成过程,橄榄石和斜方辉石呈分离/堆晶相;矿物结晶顺序是：尖晶石/橄榄石—→斜方辉石—→单斜辉石—→单斜辉石＋斜长石—→褐色普通角闪石/黑云母.原生岩浆可能来自原始地幔或中等程度熔融的高镁玄武质岩浆,属拉斑玄武岩系列,形成过程中受到了一定程度同化混染作用的影响,但硫化物熔离程度较弱.岩浆源区位于尖晶石稳定域.

英文摘要：

The Jikelikuole mafic-ultramafic rocks in Qiemo County,Xinjiang,is located on the north side of the central section of Late Paleozoic Karamilan arc,the southern active belt margin of the Tarim plate,intruded into the formation of marine clastic rocks,carbonate rocks and intermediate-acidic volcanic rocks,the Third Member of Carboniferous Mandelaqiapu Formation.The mafic-ultramafic rocks are dunite,lherzolite,wehrlite,plagioclase-bearing olivine websterite,websterite,olivine-gabbro,leucogabbro.Geochemical and petrographic characteristics show that fractional crystallization dominates the magma evolution and formation of the rocks during early magmatism,and olivine and orthopyroxene are the fractional/cumulated phases; the mineral crystal order is：spinel/olivine —→ orthopyroxene —→ clinopyroxene —→ clinopyroxene ＋ plagioclase —→ brown hornblende/biotite.Primary magma may come from the primitive mantle or the Mg-high basaltic magma about moderate degree of partial melting.The magma is originated from the the spinel stability domain and belongs to the tholeiitic series,which has undergone little immiscible separation of metal sulfide.