Very Low-Grade Metamorphism of Clastic Rocks from the   Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang   in Northeastern Hunan Province and Its Geological Implications

doi:10.1111/1755-6724.12813

CORC > 北京大学 > 地球与空间科学学院

	Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications
	Wang Hejing ; Yuan Lei ; Wang Ling ; Zhou Zhao ; An Jiali
刊名	ACTA GEOLOGICA SINICA-ENGLISH EDITION
	2016
关键词	diagenesis very low-grade metamorphism illite crystallinity Meso-Neoproterozoic lower palaeozoic SOUTH CHINA CRYSTALLITE SIZE TECTONOTHERMAL EVOLUTION INCIPIENT METAMORPHISM ILLITE CRYSTALLINITY EASTERN SWITZERLAND CATHAYSIA BLOCKS CLAY-MINERALS CENTRAL ALPS WHITE MICA
DOI	10.1111/1755-6724.12813
英文摘要	This study uses illite crystallinity, chlorite crystallinity, illite polytypes, the b(0) cell-dimension of K-white mica, clay mineral assemblages and mineral geothermo-geobarometers to investigate the overprint of diagenesis and metamorphism on the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang in northeastern Hunan Province, China. Mite crystallinity Kubler index (KI) of the <2 mu m fractions ranges from 0.225 to 0.485 degrees Delta 20 while chlorite crystallinity Arkai index (AI) ranges from 0.244 to 1.500 degrees Delta 20. This indicates that the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang were overprinted with diagenesis and anchi- to epimetamorphism. Peak metamorphic temperature is estimated with the IV site chlorite geothermometer roughly at 360 degrees C. The b(0) cell dimension values of illites (K-mica) range from 0.9002 to 0.9054 nm and, on average, at 0.9030 nm for the Meso-Neoproterozoic. Based on cumulative frequency curves of illite (K-mica) b(0) cell dimension, the peak metamorphic pressure of the Meso-Neoproterozoic along the profile Yueyang-Linxiang is derived of an intermediate pressure type. Most illites occur in the 2M(1) polytype and some of them in a mixture of 2M(1)+1M types especially those in the Paleozoic. This result partly agrees with the conclusion of the lower greenschist and greenschist facies of the Lengjiaxi and Banxi Groups. However, it is not agreed with the sedimentary cover from the Sinian to the Lower Paleozoic or from the Banxi Group to the Lower Paleozoic. Crustal thickening due to "collision" between the Yangtze and Cathaysia blocks led to an increase in the thickness of the Meso-Neoproterozoic to ca. 14 km and resulted in a temperature increase in those rocks due to burial. The very low grade to low grade metamorphism overprinting the Meso-Neoproterozoic implies that the so called "Chiangnania or Jiangnan orogen" was no relative with the "Grenvillian orogeney; instead, it might be a continuous amalgamation product between the Yangtze and Cathaysia blocks.; National Natural Science Foundation of China [41372061, 40821002]; SCI(E); 中国科学引文数据库(CSCD); ARTICLE; hjwang@pku.edu.cn; 5; 1743-1753; 90
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/458795]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Wang Hejing,Yuan Lei,Wang Ling,et al. Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications[J]. ACTA GEOLOGICA SINICA-ENGLISH EDITION,2016.
APA	Wang Hejing,Yuan Lei,Wang Ling,Zhou Zhao,&An Jiali.(2016).Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications.ACTA GEOLOGICA SINICA-ENGLISH EDITION.
MLA	Wang Hejing,et al."Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications".ACTA GEOLOGICA SINICA-ENGLISH EDITION (2016).