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塔里木板块西南缘克里阳山区的钾质煌斑岩呈脉状产于前寒武纪埃连卡特群变质沉积岩中,其主要岩石类型有:金云母透辉石煌斑岩、假白榴石透辉石煌斑岩和含球粒透辉石煌斑岩。所有岩石具有低的SiO2(41.31%~44.84%)、TiO2(0.75%~0.86%)和高的MgO(7.30%~11.33%)和K2O(4.01%~6.01%)含量,K2O/Na2O比值介于2.77~12.49之间。同时,它们具有富集大离子亲石元素(Rb、Sr、Ba、Th、U、K)和轻稀土元素(LREE),相对亏损高场强元素(Nb、Ta、Zr、Hf、Ti)的特征,并且具有高的Sr同位素比值、相似的高度分异的REE配分模式。这些岩石的母岩浆来自于金云母角闪石石榴子石二辉橄榄岩的富集地幔,是该富集地幔部分熔融约5%~10%的产物,岩浆在上升侵位过程中受到地壳物质的混染较弱。富集地幔是俯冲的板块释放的富含钾质流体交代的结果。
The potash lamprophyre in the Kiyang Mountains in the southwestern margin of the Tarim plate is vein-shaped in the Precambrian Ellicase metamorphic sedimentary rocks. The main types of rocks are phlogopite diopside pegmatite, Diopside lamprophyres and pelletoid diopside lamprophyres. All rocks have low SiO2 (41.31% ~ 44.84%), TiO2 (0.75% ~ 0.86%), high MgO (7.30% ~ 11.33%) and K2O (4.01% ~ 6.01%) with K2O / Between 2.77 and 12.49. At the same time, they have the characteristics of enrichment of large ion lithophile elements (Rb, Sr, Ba, Th, U, K) and light rare earth elements (LREE), relatively depleted high field strength elements (Nb, Ta, Zr, Hf, Ti) Features, and has a high ratio of Sr isotopes, a similar pattern of highly-distinct REE partitioning. The parent magma of these rocks is derived from the enriched mantle of the phlogopite amphibolite garnet lherzolite and is the product of partial melting of the enriched mantle by about 5% to 10%. The magma was mixed with crustal material during the upwelling Dye weaker. The enriched mantle is the result of the exchange of potash-rich fluids released from subducted plates.