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辽宁阜新白垩纪玄武岩的出现为了解中生代时期华北北缘地幔过程提供了可能. 阜新碱锅玄武岩为火山通道相, 柱状节理发育, 并含少量的尖晶石二辉橄榄岩和辉石岩捕虏体. 其化学组成贫硅、富碱、高钛和铝, 属碱性玄武岩. 在微量元素组成上, 碱锅玄武岩中等程度地富集轻稀土元素和大离子亲石元素, 但不亏损高场强元素. 其Sr同位素比值低, Nd和Pb同位素比值高. 这表明碱锅玄武岩起源于亏损的软流圈地幔, 代表未分异无混染的原始岩浆. 该玄武岩的出现暗示华北北缘此时的岩石圈厚度小于65 km, 岩石圈地幔主要由“富集”的含韭闪石尖晶石二辉橄榄岩和斜长石辉石岩组成. 早侏罗~晚白垩大量且持续的中基-中酸性岩浆活动表明华北北缘岩石圈减薄作用的开始和结束时间较华北南缘的早, 因为鲁西南地区大量的中基性火山活动仅出现于白垩纪, 而且具软流圈同位素特征的玄武岩出现在第三纪, 显示华北岩石圈演化的时空不均一性.
The occurrence of Cretaceous basalts in Fuxin, Liaoning Province may provide a basis for understanding the mantle processes in the northern North China during the Mesozoic Era. Fuxin caustic basalt basalts are volcanic channel facies with columnar joints developed with a small amount of spinel lherzolite and pyroxenite xenoliths. Its chemical composition is poor in silicon, alkali-rich, high-titanium and aluminum, which are alkaline basalts. In the composition of trace elements, alkali-light basalts are enriched in light rare earth elements and large ion lithophile elements to a certain extent, With low Sr isotope ratios and high ratios of Nd and Pb isotopes, suggesting that the caustic basalt basalt originated from a depleted asthenosphere mantle, representing undifferentiated and undisturbed primary magma.The presence of this basalt suggests that the northern North China margin The lithosphere thickness is less than 65 km and the lithospheric mantle is mainly composed of “enriched” leechesite-bearing spodumene-lherzolite and plagioclase pyroxeneite.Major and persistent medium-base acidity The magmatic activity indicates that the lithospheric thinning in the northern part of North China started earlier and ended earlier than that in the southern part of North China because a large amount of Meso-base volcanic activity in the southwestern part of the Cretaceous occurred only in the Cretaceous period, Basalt isotopic characteristics appear in Tertiary, display temporal evolution CHINA lithosphere heterogeneity.