Geochronology, origin, sources and tectonic settings of Late Mesozoic two-stage granites in the Ganzhuermiao region, central and southern Da Hinggan Range, NE China

	Geochronology, origin, sources and tectonic settings of Late Mesozoic two-stage granites in the Ganzhuermiao region, central and southern Da Hinggan Range, NE China
	Yang QiDi 4; Guo Lei ; Wang Tao ; Zeng Tao 1; Zhang Lei ; Tong Ying ; Shi XingJun ; Zhang JianJun 2
刊名	ACTA PETROLOGICA SINICA
	2014
卷号	30 期号:7 页码:1961-1981
关键词	Granite Zircon U-Pb age Late Mesozoic Hf isotope Ganzhuermiao Central and southern Da Hinggan Range
ISSN号	1000-0569
英文摘要	The Da Hinggan Range (Great Xing' an Range) is located in the eastern section of the Central Asian Orogenic Belt (CAOB) and also regarded as the middle-western section of the Xing-Meng Orogenic Belt. It experienced strong magmatic activities that produced widespread granitoid intrusions during Late Mesozoic. Those granitoids have been studied intensively, but few of them have been reported from the Ganzhuermiao region in the middle-southern Da Hinggan Range. In this study, we first present the zircon U-Pb dating results and geochemistry data of five Late Mesozoic granitic plutons in the Ganzhuermiao region and discuss the origin and tectonic settings as well as the implications for understanding of the Late Mesozoic tectono-magmatic evolution in NE Asia together with other research.. These data show the granitoids were formed in Late Jurassic (154Ma) and Early Cretaceous (139 similar to 125Ma). The time of emplacement consistents with the eruption time of volcanic rocks and peak time of the Late Mesozoic granitoids in NE Asia. The Late Jurassic granitic intrusions are biotite syengranites and the Early Cretaceous plutons are biotite monzogranite and granite porphyry. The Late Jurassic Tumufuzhou pluton with an area of 100km(2), located in southwest of the Ganzhuermiao region. They were emplaced in Permian and Jurassic strata, made up of dozens of stocks. The Early Cretaceous granitoids cover area over 180km(2). The early stage of the Early Cretaceous granitoids include Wulandaba, Xiaojingzi and Huajialaga plutons. The first two are situated in the center and southern of the study area, presenting as batholiths and intruding into the Permian and Jurassic strata. The Balimuhade pluton, intruded in the late stage of the Early Cretaceous, located in the western of the Ganzhuermiao region as large as 90km(2). The mainly body were emplaced in Jurassic volcanic rocks with clear boundaries between them, indicating this intrusion is subvolcanics or middle-shallow rocks. They are all characterized by high SiO2 (69. 96% similar to 75. 85%) and enrichment of K2O (4. 58% similar to 5. 45%). Their A/CNK ratios is from 0. 98 to 1. 14, indicating the metaluminous and peraluminous granitoids. These granitoids also present low Sr (25. 1 x 10(-6) similar to 262.1 x 10(-6) with average of 84. 05 x 10(-6)), high Y (18.1 X 10(-6) similar to 46.1 x 10(-6) with average of 29. 93 x 10(-6)) and low Sr/Y ratio (0. 97 similar to 12. 55). The REE contents of them are between 82. 17 x 10(-6) to 216.6 x 10(-6), with delta Eu value of 0. 06 similar to 0. 58 and (La/Yb)(N) ratio of 3. 42 to 11. 48. Their REE patterns are characterized by enrichment of LREE relatively to HREE and negative Eu anomalies in chondrite-normalized REE diagram. Their trace elements relatively enrich large ion lithophile elements (LILE), high field strength elements (HFSE) and poor Ba, Sr, Ti, P, with notable depletion of Nb and Ta. The differentiation degree of the Early Cretaceous granitoids are higher than that of the Late Jurassic granitoids. All these indicate that these granitoids belong to the high potassic calc-alkaline series and show features of highly differentiated I-type granitoids. The geochemical signatures above are similar to those of post-orogenic granitoids in the adjacent area. Model age of zircon Hf isotopic of these granitoids range from 174Ma to 680Ma, suggesting juvenile sources for the granitoids. Furthermore, the epsilon(Hf)(t) values (+ 9. 9 similar to + 15. 9) of the Late Jurassic granitoids are higher than those of the underplated juvenile lower crust in study. This implies that sources of these granitoids may be more juvenile than underplated materials. The epsilon(Hf)(t) values (+3. 4 similar to + 13. 9) of the Early Cretaceous granitoids are slightly lower, which suggests that their sources may be derived from a mixture of underplated juvenile lower crust and Paleozoic subduction-accretionary assemblages. From Late Jurassic to Early Cretaceous, the epsilon(Hf)(t) values of zircons decreased which implies more younger underplated materials involved. The younger HI isotope model ages of the granitoids imply that this area experienced crustal growth during Late Mesozoic. Combined with regional geology, we suggest that the Late Mesozoic granitoids in the Ganzhuermiao region were formed in an extensional setting which may be related to the post-orogenic extengon following the closure of the Mongolia-Okhotsk ocean to the northwest rather than the subduction of the Paleo-Pacific plate to the east.
学科主题	火成岩岩石学
WOS关键词	U-PB AGES ; NORTHERN INNER-MONGOLIA ; A-TYPE GRANITES ; GEOCHEMICAL CHARACTERISTICS ; LINXI GRANITOIDS ; SOLONKER SUTURE ; CRUSTAL GROWTH ; OROGENIC BELT ; ICP-MS ; PETROGENESIS
WOS研究方向	Geology
语种	中文
出版者	SCIENCE PRESS
WOS记录号	WOS:000339456100011
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/40572]
专题	中国地质科学院地质研究所
作者单位	1.Chinese Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China 2.E China Inst Technol, Fuzhou 330013, Peoples R China 3.China Univ Geosci, Beijing 100083, Peoples R China 4.中国地质科学院地质研究所
推荐引用方式 GB/T 7714	Yang QiDi,Guo Lei,Wang Tao,et al. Geochronology, origin, sources and tectonic settings of Late Mesozoic two-stage granites in the Ganzhuermiao region, central and southern Da Hinggan Range, NE China[J]. ACTA PETROLOGICA SINICA,2014,30(7):1961-1981.
APA	Yang QiDi.,Guo Lei.,Wang Tao.,Zeng Tao.,Zhang Lei.,...&Zhang JianJun.(2014).Geochronology, origin, sources and tectonic settings of Late Mesozoic two-stage granites in the Ganzhuermiao region, central and southern Da Hinggan Range, NE China.ACTA PETROLOGICA SINICA,30(7),1961-1981.
MLA	Yang QiDi,et al."Geochronology, origin, sources and tectonic settings of Late Mesozoic two-stage granites in the Ganzhuermiao region, central and southern Da Hinggan Range, NE China".ACTA PETROLOGICA SINICA 30.7(2014):1961-1981.