Geochemical characteristics and sedimentary environments of siliceous in the middle and western parts of the Shiquanhe-Yongzhu-Jiali tectonic belt

doi:10.13745/j.esf.sf.2020.4.1

Abstract

Abstract:

The geochemistry of radiolarian siliceous, as sedimentary cover of ophiolite, plays a role in investigating the formation environment of ophiolite and tectonic-paleogeographic evolution of the sedimentary basin. In this paper, we studied the petrology and whole-rock geochemistry of Guchang siliceous in the western part of the Shiquanhe-Yongzhu-Jiali tectonic belt (SYJTB), and carried out a comparative analysis involving Laguoco and Guomangco siliceous to determine the origin and sedimentary environments of siliceous in these areas. The low SiO₂ content and Al/(Al+Fe+Mn) ratio (0.87-0.95) indicate a non-hydrothermal origin of Guchang siliceous. The rare earth element (REE) patterns of most of these rocks show left-leaning types with slight light REE (LREE) and obvious Eu depletion and no Ce anomalies. The Y/Ho, Ti/V and V/Y ratios in Guchang siliceous are 21-24, 220.67-862.02 and 0.05-0.29, respectively. These results suggest that Guchang siliceous is formed in a continental margin environment. The characteristics of Laguoco and Guchang siliceous were similar. However, Guomangco siliceous has some oceanic basin siliceous characteristics affected slightly by hydrothermal fluids, indicating its probable formation in a more mature oceanic basin. Combining with the ophiolite data, the middle and western part of the SYJTB likely represent an ancient oceanic basin near the continental margin, and the oceanic basin in Guomangco is more mature and wider than that those in Guchang and Laguoco.

Key words: Tibetan Plateau, Shiquanhe-Yongzhu-Jiali tectonic belt, siliceous, geochemistry, sedimentary environment

CLC Number:

P584
P595

XU Mengjing, ZHAO Peiyun, LAN Rui, WU Yanwang, XIAO Xue, ZHANG Jinbo. Geochemical characteristics and sedimentary environments of siliceous in the middle and western parts of the Shiquanhe-Yongzhu-Jiali tectonic belt[J]. Earth Science Frontiers, 2020, 27(3): 182-190.

Figures/Tables 8

Fig.1 Regional geological sketch map of Guchang. Modified from [5,9,23-25].

Fig.2 Field and microscopic characteristics of Guchang siliceous

Table 1 Results of major and trace elemental analysis of Guchang siliceous

样品编号	w_B/%												w_B/10^-6
样品编号	SiO₂	Al₂O₃	TiO₂	Fe₂ $O 3 T$	CaO	MgO	Na₂O	K₂O	P₂O₅	MnO	LOI	Total	Li	Be	V	Cr	Co	Ni	Cu	Zn	Ga	Rb	Sr		Zr		Mo
Q7T11h1	81.26	10.54	0.07	1.04	0.38	0.09	4.18	0.97	0.01	0.03	1.08	99.55	11.37	1.12	1.85	4.17	1.39	3.43	2.34	30.70	8.52	28.01	96.10		100		0.30
Q7T11h2	73.34	14.89	0.13	0.56	0.36	0.03	7.44	0.64	0.02	0.01	0.79	98.15	6.44	1.47	0.90	9.68	2.37	2.96	2.57	18.87	9.75	10.77	114		232		0.47
Q7T11h3	78.55	12.20	0.16	0.79	0.42	0.16	3.47	1.91	0.03	0.02	1.47	99.10	13.34	1.47	2.93	4.93	1.43	1.41	2.93	17.57	12.15	48.32	70.16		177		0.24
Q7T11h4	78.07	11.54	0.16	0.97	0.84	0.10	5.50	0.46	0.03	0.04	1.29	98.90	6.80	1.07	3.83	5.41	2.48	3.97	4.56	28.49	6.85	5.83	83.75		157		0.15
Q7T11h5	75.92	12.68	0.13	1.05	0.66	0.20	6.45	0.11	0.03	0.05	1.10	98.27	9.39	0.73	3.03	5.36	1.22	2.66	6.13	17.34	8.95	0.77	56.25		121		1.95
Q7T11h6	82.79	9.13	0.14	1.05	0.30	0.06	4.29	0.16	0.02	0.03	0.87	98.73	11.53	0.77	3.80	3.47	1.08	1.41	3.05	29.64	6.79	1.24	38.78		136		1.00
Q7T11h7	79.06	10.46	0.14	0.98	1.67	0.13	3.66	1.33	0.03	0.02	2.11	99.50	6.74	1.34	2.50	4.51	1.12	0.73	3.60	30.40	10.77	31.38	95.36		180		1.15
Q7T11h8	81.50	10.23	0.09	0.59	0.27	0.10	0.63	6.09	0.01	0.03	0.91	100.39	5.86	0.87	1.93	4.58	0.82	0.78	3.18	11.83	7.30	155	47.19		108		0.11
样品编号	w_B/10^-6
样品编号	Y	Nb	Cs	Ba	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu	Hf	Ta	Pb	Bi	Th		U		ΣREE
Q7T11h1	11.4	13.28	0.92	222	9.46	26.57	3.00	11.85	3.02	0.42	3.02	0.48	2.75	0.55	1.63	0.29	2.17	0.33	4.55	1.25	27.08	0.25	14.67	2.08		65.54
Q7T11h2	19.24	18.53	0.39	173	26.56	58.79	6.80	26.08	5.46	0.77	5.25	0.79	4.53	0.94	2.85	0.43	3.11	0.47	7.91	1.43	19.25	0.24	15.46	2.83		142.84
Q7T11h3	20.70	15.26	1.39	409	32.14	64.47	7.75	28.72	5.70	0.56	5.34	0.79	4.47	0.93	3.01	0.44	2.97	0.46	6.01	1.35	26.75	0.47	18.99	3.57		157.76
Q7T11h4	19.71	14.82	0.65	119	18.68	42.37	5.20	20.49	4.68	0.64	4.84	0.74	4.35	0.89	2.71	0.40	2.78	0.40	5.53	1.21	27.77	0.47	14.88	3.27		109.18
Q7T11h5	17.16	10.47	0.20	25.18	21.61	42.61	4.98	18.17	3.63	0.61	3.58	0.54	3.33	0.72	2.28	0,34	2.38	0.36	4.42	0.87	13.21	0.13	11.63	2.42		105.14
Q7T11h6	12.90	14.49	0.20	26.08	9.74	30.25	3.02	11.76	2.73	0.35	2.84	0.46	2.91	0.60	1.88	0.29	2.04	0.31	5.07	1.11	25.58	0.48	10.73	2.45		69.16
Q7T11h7	32.89	14.79	1.08	351	40.16	79.89	9.16	35.02	7.25	0.72	7.51	1.17	6.89	1.40	4.27	0.61	3.90	0.57	5.88	1.18	33.80	0.39	21.34	3.37		198.54
Q7T11h8	11.38	11.26	1.94	868	34.45	69.05	7.42	26.51	4.72	0.57	4.26	0.52	2.67	0.48	1.42	0.19	1.20	0.17	4.06	0.95	25.58	0.32	12.93	2.54		153.64

Table 1 Results of major and trace elemental analysis of Guchang siliceous

样品编号	w_B/%												w_B/10^-6
样品编号	SiO₂	Al₂O₃	TiO₂	Fe₂ $O 3 T$	CaO	MgO	Na₂O	K₂O	P₂O₅	MnO	LOI	Total	Li	Be	V	Cr	Co	Ni	Cu	Zn	Ga	Rb	Sr		Zr		Mo
Q7T11h1	81.26	10.54	0.07	1.04	0.38	0.09	4.18	0.97	0.01	0.03	1.08	99.55	11.37	1.12	1.85	4.17	1.39	3.43	2.34	30.70	8.52	28.01	96.10		100		0.30
Q7T11h2	73.34	14.89	0.13	0.56	0.36	0.03	7.44	0.64	0.02	0.01	0.79	98.15	6.44	1.47	0.90	9.68	2.37	2.96	2.57	18.87	9.75	10.77	114		232		0.47
Q7T11h3	78.55	12.20	0.16	0.79	0.42	0.16	3.47	1.91	0.03	0.02	1.47	99.10	13.34	1.47	2.93	4.93	1.43	1.41	2.93	17.57	12.15	48.32	70.16		177		0.24
Q7T11h4	78.07	11.54	0.16	0.97	0.84	0.10	5.50	0.46	0.03	0.04	1.29	98.90	6.80	1.07	3.83	5.41	2.48	3.97	4.56	28.49	6.85	5.83	83.75		157		0.15
Q7T11h5	75.92	12.68	0.13	1.05	0.66	0.20	6.45	0.11	0.03	0.05	1.10	98.27	9.39	0.73	3.03	5.36	1.22	2.66	6.13	17.34	8.95	0.77	56.25		121		1.95
Q7T11h6	82.79	9.13	0.14	1.05	0.30	0.06	4.29	0.16	0.02	0.03	0.87	98.73	11.53	0.77	3.80	3.47	1.08	1.41	3.05	29.64	6.79	1.24	38.78		136		1.00
Q7T11h7	79.06	10.46	0.14	0.98	1.67	0.13	3.66	1.33	0.03	0.02	2.11	99.50	6.74	1.34	2.50	4.51	1.12	0.73	3.60	30.40	10.77	31.38	95.36		180		1.15
Q7T11h8	81.50	10.23	0.09	0.59	0.27	0.10	0.63	6.09	0.01	0.03	0.91	100.39	5.86	0.87	1.93	4.58	0.82	0.78	3.18	11.83	7.30	155	47.19		108		0.11
样品编号	w_B/10^-6
样品编号	Y	Nb	Cs	Ba	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu	Hf	Ta	Pb	Bi	Th		U		ΣREE
Q7T11h1	11.4	13.28	0.92	222	9.46	26.57	3.00	11.85	3.02	0.42	3.02	0.48	2.75	0.55	1.63	0.29	2.17	0.33	4.55	1.25	27.08	0.25	14.67	2.08		65.54
Q7T11h2	19.24	18.53	0.39	173	26.56	58.79	6.80	26.08	5.46	0.77	5.25	0.79	4.53	0.94	2.85	0.43	3.11	0.47	7.91	1.43	19.25	0.24	15.46	2.83		142.84
Q7T11h3	20.70	15.26	1.39	409	32.14	64.47	7.75	28.72	5.70	0.56	5.34	0.79	4.47	0.93	3.01	0.44	2.97	0.46	6.01	1.35	26.75	0.47	18.99	3.57		157.76
Q7T11h4	19.71	14.82	0.65	119	18.68	42.37	5.20	20.49	4.68	0.64	4.84	0.74	4.35	0.89	2.71	0.40	2.78	0.40	5.53	1.21	27.77	0.47	14.88	3.27		109.18
Q7T11h5	17.16	10.47	0.20	25.18	21.61	42.61	4.98	18.17	3.63	0.61	3.58	0.54	3.33	0.72	2.28	0,34	2.38	0.36	4.42	0.87	13.21	0.13	11.63	2.42		105.14
Q7T11h6	12.90	14.49	0.20	26.08	9.74	30.25	3.02	11.76	2.73	0.35	2.84	0.46	2.91	0.60	1.88	0.29	2.04	0.31	5.07	1.11	25.58	0.48	10.73	2.45		69.16
Q7T11h7	32.89	14.79	1.08	351	40.16	79.89	9.16	35.02	7.25	0.72	7.51	1.17	6.89	1.40	4.27	0.61	3.90	0.57	5.88	1.18	33.80	0.39	21.34	3.37		198.54
Q7T11h8	11.38	11.26	1.94	868	34.45	69.05	7.42	26.51	4.72	0.57	4.26	0.52	2.67	0.48	1.42	0.19	1.20	0.17	4.06	0.95	25.58	0.32	12.93	2.54		153.64

Fig.3 NASC-normalized REE diagrams for Guchang siliceous. Data from [28,29].

Table 2 Comparison of elemental ratios of Guchang,Laguoco and Guomangco siliceous

地点	样品编号	(La/Yb)_SN	(La/Ce)_SN	Eu/Eu^*	Ce/Ce^*	Th/Sc	Th/U	Al/(Al+Fe+Mn)	Si/(Si+Al+Ca+Fe)	Al₂O₃/TiO₂	Y/Ho
古昌	Q7T11h1	0.42	0.81	0.61	1.09	9.97	7.06	0.88	0.85	150.57	20.66
	Q7T11h2	0.83	1.03	0.63	0.95	3.48	5.45	0.95	0.80	114.54	20.52
	Q7T11h3	1.05	1.14	0.45	0.89	8.37	5.31	0.92	0.83	76.25	22.15
	Q7T11h4	0.65	1.01	0.59	0.94	8.15	4.55	0.90	0.83	72.13	22.12
	Q7T11h5	0.88	1.16	0.75	0.89	3.13	4.81	0.90	0.82	97.54	24.00
	Q7T11h6	0.46	0.73	0.55	1.22	6.66	4.37	0.87	0.87	65.21	21.53
	Q7T11h7	1.00	1.15	0.43	0.91	8.28	6.33	0.89	0.83	74.71	23.43
	Q7T11h8	2.77	1.14	0.56	0.94	39.17	5.09	0.93	0.86	113.67	23.70
果芒错^[28]	q11T4H1	1.00	1.13	0.94	0.94	0.19	2.90	0.55	0.79	24.92	27.01
	q11T4H2	0.98	1.16	1.03	0.93	0.24	2.84	0.58	0.81	23.93	26.96
	q11T4H3	0.99	1.16	1.04	0.92	0.36	4.86	0.60	0.75	22.71	28.26
	q11T4H4	0.98	1.17	1.09	0.92	0.37	6.42	0.59	0.76	24.45	27.69
	q11T4H5	0.88	1.16	1.08	0.92	0.24	4.61	0.57	0.78	22.15	27.57
拉果错^[29]	PM001Gs15	0.58	1.04	0.89	0.97	2.58	8.55	0.81	0.85	53.41	25.09

Fig.4 V/Y vs. Ti/V diagram for the Guchang siliceous.Adapted from[30].

Fig.5 (a) Plot of Th/Sc vs. La/Cr and (b) triangular La-Th-Sc diagram for Guchang siliceous. Adapted from [43-44].

Fig.6 Discriminant diagrams for depositional settings of Guchang siliceous. Adapted from [41].

References 54

[1]	COWARD M P, KIDD W S F, YUN P, et al. The structure of the 1985 Tibet geotraverse, Lhasa to Golmud[J]. Philosophical Transactions of the Royal Society of London Series A, Mathematical and Physical Sciences, 1988, 327(1594):307-333. DOI URL
[2]	GIRARDEAU J, MARCOUX J, ALLEGRE C J, et al. Tectonic environment and geodynamic significance of the Neo-Cimmerian Donqiao ophiolite, Bangong-Nujiang suture zone, Tibet[J]. Nature, 1984, 307(5946):27-31. DOI URL
[3]	KAPP P, MURPHY M A, YIN A, et al. Mesozoic and Cenozoic tectonic evolution of the Shiquanhe area of western Tibet[J]. Tectonics, 2003, 22(4):1029-1053.
[4]	张玉修. 班公湖—怒江缝合带中西段构造演化[D]. 广州: 中国科学院研究生院(广州地球化学研究所), 2007: 1-268.
[5]	XU M J, LI C, ZHANG X, et al. Nature and evolution of the Neo-Tethys in central Tibet: synjournal of ophiolitic petrology, geochemistry, and geochronology[J]. International Geology Review, 2014, 56(9):1072-1096. DOI URL
[6]	ZHU D C, ZHAO Z D, NIU Y L, et al. The Lhasa Terrane: record of a microcontinent and its histories of drift and growth[J]. Earth and Planetary Science Letters, 2011, 301(1/2):241-255. DOI URL
[7]	耿全如, 潘桂棠, 王立全, 等. 班公湖—怒江带、羌塘地块特提斯演化与成矿地质背景[J]. 地质通报, 2011, 30(8):1261-1274.
[8]	胡承祖. 狮泉河—古昌—永珠蛇绿岩带特征及其地质意义[J]. 成都地质学院学报, 1990, 17(1):23-30.
[9]	潘桂棠, 莫宣学, 侯增谦, 等. 冈底斯造山带的时空结构及演化[J]. 岩石学报, 2006, 22(3):521-533.
[10]	徐建鑫, 李才, 范建军, 等. 西藏改则县拉果错蛇绿岩构造属性:来自岩石学、地球化学、年代学及Lu-Hf同位素的制约[J]. 地质通报, 2018, 37(8):1541-1553.
[11]	ZENG Y C, XU J F, CHEN J L, et al. Geochronological and geochemical constraints on the origin of the Yunzhug ophiolite in the Shiquanhe-Yunzhug-Namu Tso ophiolite belt, Lhasa Terrane, Tibetan Plateau[J]. Lithos, 2018, 300:250-260.
[12]	CHEN D Z, QING H R, YAN X, et al. Hydrothermal venting and basin evolution(Devonian, South China): constraints from rare earth element geochemistry of chert[J]. Sedimentary Geology, 2006, 183(3):203-216. DOI URL
[13]	OWEN A W, ARMSTRONG H A, FLOYD J D. Rare earth elements in chert clasts as provenance indicators in the Ordovician and Silurian of the Southern Uplands of Scotland[J]. Sedimentary Geology, 1999, 124(1/2/3/4):185-195. DOI URL
[14]	GARBAN G, MARTINEZ M, MARQUEZ G, et al. Geochemical signatures of bedded cherts of the upper La Luna formation in Tachira State, western Venezuela: assessing material provenance and paleodepositional setting[J]. Sedimentary Geology, 2017, 347:130-147. DOI URL
[15]	JOSIP H, VESNA M, SPELA G. Jurassic radiolarian cherts in north-western Croatia: geochemistry, material provenance and depositional environment[J]. Geologica Carpathica, 2005, 56(2):123-136.
[16]	MURRAY R W. Chemical criteria to identify the depositional environment of chert: general principles and applications[J]. Sedimentary Geology, 1994, 90(3/4):213-232. DOI URL
[17]	YU B, DONG H, WIDOM E, et al. Geochemistry of basal Cambrian black shales and cherts from the northern Tarim Basin, Northwest China: implications for depositional setting and tectonic history[J]. Journal of Asian Earth Sciences, 2009, 34(3):418-436. DOI URL
[18]	KEMKIN I V, KEMKINA R A. Geochemistry of chert rocks from the Sikhote-Alin Taukha terrane, Russia far east: significance for determination of their depositional environment[J]. Environmental Earth Sciences, 2015, 73(5):2253-2268. DOI URL
[19]	KATO Y, NAKAO K, ISOZAKI Y. Geochemistry of Late Permian to Early Triassic pelagic cherts from southwest Japan: implications for an oceanic redox change[J]. Chemical Geology, 2002, 182(1):15-34. DOI URL
[20]	付伟, 周永章, 杨志军, 等. 湘中南二叠系孤峰组硅质岩的成因属性及其地球动力学指示意义[J]. 矿物岩石地球化学通报, 2004, 23(4):292-300.
[21]	邱振, 王清晨. 湘黔桂地区中上二叠统硅质岩的地球化学特征及沉积背景[J]. 岩石学报, 2010, 26(12):3612-3628.
[22]	王卓卓, 陈代钊, 汪建国. 广西南宁地区泥盆系硅质岩地球化学特征及沉积环境[J]. 沉积学报, 2007, 25(2):239-245.
[23]	LI C, ZHAI Q, DONG Y, et al. High-pressure eclogite-blueschist metamorphic belt and closure of Paleo-Tethys ocean in central Qiangtang, Qinghai Tibet Plateau[J]. Journal of Earth Science, 2009, 20(2):209-218. DOI URL
[24]	YIN A, HARRISON T M. Geologic evolution of the Himalayan-Tibetan Orogen[J]. Annual Review of Earth and Planetary Sciences, 2000, 28(1):211-280. DOI URL
[25]	陈玉禄, 张宽忠, 勾永东, 等. 中华人民共和国区域地质调查报告物玛幅比例尺1∶250000[R]. 成都: 中国地质调查局成都地质调查中心, 2006.
[26]	张宽忠, 陈玉禄. 古昌蛇绿岩中的斜长花岗岩特征[J]. 沉积与特提斯地质, 2007, 27(1):32-37.
[27]	BOYNTON W V. Cosmochemistry of the rare earth elements: meteorite studies[M]//HENDERSON P. Developments in geochemistry. Amsterdam: Elsevier, 1984: 63-114.
[28]	徐梦婧, 李才, 吴彦旺, 等. 西藏果芒错蛇绿混杂岩中硅质岩的地球化学特征及其形成环境[J]. 地质通报, 2014, 33(7):1061-1066.
[29]	毛国正, 岳鋆璋, 卢锋锋, 等. 中华人民共和国区域地质调查报告西藏拉果错地区4幅比例尺1∶50000[R]. 拉萨: 西藏地质调查院, 2013.
[30]	MURRAY R W, BUCHHOLTZ TEN BRINK M R, GERLACH D C, et al. Rare earth, major, and trace elements in chert from the Franciscan Complex and Monterey Group, California: assessing REE sources to fine-grained marine sediments[J]. Geochimica et Cosmochimica Acta, 1991, 55(7):1875-1895. DOI URL
[31]	ADACHI M, YAMAMOTO K, SUGISAKI R. Hydrothermal chert and associated siliceous rocks from the northern Pacific their geological significance as indication od ocean ridge activity[J]. Sedimentary Geology, 1986, 47(1/2):125-148. DOI URL
[32]	YAMAMOTO K. Geochemical characteristics and depositional environments of cherts and associated rocks in the Franciscan and Shimanto Terranes[J]. Sedimentary Geology, 1987, 52(1/2):65-108. DOI URL
[33]	BOSTROM K, PETERSON M N A. The origin of aluminum-poor ferromanganoan sediments in areas of high heat flow on the east pacific rise[J]. Marine Geology, 1969, 7(5):427-447. DOI URL
[34]	RUIZ-ORTIZ P A, BUSTILLO M A, MOLINA J M. Radiolarite sequences of the Subbetic, Betic cordillera, southern Spain[C]// Siliceous deposits of the Tethys and Pacific regions. New York: Springer, 1989: 107-127.
[35]	杜远生, 朱杰, 顾松竹. 北祁连肃南一带奥陶纪硅质岩沉积地球化学特征及其多岛洋构造意义[J]. 地球科学: 中国地质大学学报, 2006, 31(1):101-109.
[36]	MICHARD A, ALBAREDE F, MICHARD G, et al. Rare-earth elements and uranium in high-temperature solutions from East Pacific Rise hydrothermal vent field(13°N)[J]. Nature, 1983, 303(5920):795-797. DOI URL
[37]	MICHARD A. Rare earth element systematics in hydrothermal fluids[J]. Geochimica et Cosmochimica Acta, 1989, 53(3):745-750. DOI URL
[38]	DOUVILLE E, BIENVENU P, CHARLOU J L, et al. Yttrium and rare earth elements in fluids from various deep-sea hydrothermal systems[J]. Geochimica et Cosmochimica Acta, 1999, 63(5):627-643. DOI URL
[39]	HUANG H, YUANSHENG D U, HUANG Z Q, et al. Depositional chemistry of chert during late Paleozoic from western Guangxi and its implication for the tectonic evolution of the Youjiang Basin[J]. Science China: Earth Sciences, 2013, 56(3):479-493. DOI URL
[40]	HAYASHI K I, FUJISAWA H, HOLLAND H D, et al. Geochemistry of ~1.9 Ga sedimentary rocks from northeastern Labrador, Canada[J]. Geochimica et Cosmochimica Acta, 1997, 61(19):4115-4137. DOI URL
[41]	GIRTY G H, RIDGE D L, KNAACK C, et al. Provenance and depositional setting of Paleozoic chert and argillite, Sierra Nevada, California[J]. Journal of Sedimentary Research, 1996, 66(1):107-118.
[42]	TAYLOR S R, MCLENNAN S M. The geochemical evolution of the continental crust[J]. Reviews of Geophysics, 1995, 33(2):241-265. DOI URL
[43]	PIOVANO E L, ROSS G R, GUEVARA S R, et al. Geochemical tracers of source rocks in a Cretaceous to Quaternary sedimentary sequence (Eastern Sierras Pampeanas, Argentina)[J]. Journal of South American Earth Sciences, 1999, 12(5):489-500. DOI URL
[44]	TRIBOVILLARD N, ALGEO T J, LYONS T, et al. Trace metals as paleoredox and paleoproductivity proxies: an update[J]. Chemical Geology, 2006, 232(1):12-32. DOI URL
[45]	MURRAY R W, BUCHHOLTZ TEN BRINK M R, JONES D L, et al. Rare earth elements as indicators of different marine depositional environments in chert and shale[J]. Geology, 1990, 18(3):268-271. DOI URL
[46]	TAYLOR S R, MCLENNAN S M. The continental crust: its composition and evolution[M]. Oxford: Blackwell Scientific Publications, 1985: 1-328.
[47]	KAMBER B S, GREIG A, COLLERSON K D. A new estimate for the composition of weathered young upper continental crust from alluvial sediments, Queensland, Australia[J]. Geochimica et Cosmochimica Acta, 2005, 69(4):1041-1058. DOI URL
[48]	MINAMI M, MASUDA A, TAKAHASHI K, et al. Y-Ho fractionation and lanthanide tetrad effect observed in cherts[J]. Geochemical Journal, 1998, 32(6):405-419. DOI URL
[49]	王振, 叶培盛, 张绪教, 等. 藏北果芒错蛇绿岩中堆晶岩地球化学特征及其地质意义[J]. 现代地质, 2017, 31(3):486-497.
[50]	李瑜. 西藏纳木错西蛇绿岩成岩成矿作用[D]. 成都: 成都理工大学, 2016: 1-62.
[51]	XU M, LI C, XU W, et al. Petrology, geochemistry and geochronology of gabbros from the Zhongcang ophiolitic melange, central Tibet: implications for an intra-oceanic subduction zone within the Neo-Tethys Ocean[J]. Journal of Earth Science, 2014, 25(2):224-240. DOI URL
[52]	XU M, LI C, WU Y, et al. The Petrology, geochemistry, and petrogenesis of E-MORB type mafic rocks from the Guomangco ophiolitic melange, Tibet[J]. Acta Geologica Sinica(English Edition), 2014, 88(5):1437-1453.
[53]	YUAN Y, YIN Z, LIU W, et al. Tectonic evolution of the Meso-Tethys in the Western Segment of Bangonghu-Nujiang Suture Zone: insights from geochemistry and geochronology of the Lagkor Tso ophiolite[J]. Acta Geologica Sinica(English Edition), 2015, 89(2):369-388.
[54]	WANG W L, AITCHISON J C, LO C H, et al. Geochemistry and geochronology of the amphibolite blocks in ophiolitic melanges along Bangong-Nujiang suture, central Tibet[J]. Journal of Asian Earth Sciences, 2008, 33(1/2):122-138. DOI URL