【摘 要】
:
Samples were systematically collected from metamorphic basic volcanic rocks in the Jiehekou and Xiyupi areas on both sides of the Lüliang Mountains, Shanxi Pro
【机 构】
:
National Astronomical Observatories,Chinese Survey & Research Center for Mineral Resources,Institute
论文部分内容阅读
Samples were systematically collected from metamorphic basic volcanic rocks in the Jiehekou and Xiyupi areas on both sides of the Lüliang Mountains, Shanxi Province and analyzed for their major elements, trace elements and rare earth elements (REE). The geochemical characteristics of their major, trace and rare-earth elements indicated that the metamorphic basic volcanic rocks in this area were emplaced in the tectonic environment like a modern continental rift. Sm-Nd and Rb-Sr isotope chronological studies demonstrated that the Jiehekou Group metamorphic basic volcanic rocks were formed during the 2600-Ma crust/mantle differentiation event, and were transformed by granulite facies metamorphism during the late Neo-Archaean period (2500 Ma ±), making the Sm-Nd systematics of the rocks reset. During the late Paleoproterozoic period (1800 Ma ±) the Rb-Sr systematics of the rocks were disturbed again in response to the Lüliang movement. Since the extent of disturbance was so weak that the Sm-Nd systematics was not affected, the age of 1600 Ma ± obtained from this area seems to be related to local magmatic activities within the craton. Research results lend no support to the idea that the Lüliang Group was formed during the Archaean. Instead, it should be formed during the Proterozoic.
其他文献
The natural gases found in the Yinggehai basin have nitrogen gas content ranging from 3.5% to 35%, and carbon dioxide content ranging from 0.1% to 93%. The nitr
Based on energy minimizing approach of bound theory, the influence of the distribution of constituent minerals on rheological property of rocks is discussed. En
当前在全军扎实开展的党的群众路线教育实践活动,是实现党在新形势下强军目标的重要手段.应在准确把握群众路线的科学内涵、深刻理解人民群众是历史创造者的思想、认真贯彻“
A dating of two biotite samples taken from the meso- and low-temperature mylonites within the Shangyi-Chicheng fault belt on the north of the North China Craton
Leg 184 of ODP recovered a record of deep- water sediments spanning the past 32.8 Ma from the South China Sea (SCS). The sediments of the Oligocene (32.8 - 23.8
Soil moisture plays an important role in water and energy balance in land-atmospheric interaction, but is impacted directly by the groundwater table. Dynamic va
It is revealed by CL images that there are multi-stage growth internal structures of zircons in the Huangtuling granulite, including the inherited zircons, prot
The accuracy of MODIS aerosol products from the NASA Terra Satellite is validated in comparison with the results of sun-photometer observations in Beijing and H
Analysis of the taxonomy and stratigraphic distribution of the Early Cambrian eodiscoid trilobites of the Yangtze Platform indicates that species of Tsunyidiscu
当今时代是信息时代,科学技术发展日新月异,社会变化翻天覆地,世界格局,风云变幻,经济全球化,社会信息化势不可当.在信息化条件下,如何抓好城市重要经济目标的防护工作?本文从