阿尔泰山喀纳斯河谷晚第四纪冰川地貌演化过程

doi:10.11821/dlxb201505006

Abstract

Abstract:

Multiple glacial advances/retreats have occurred in Kanas region of the Altay Mountains. Glacial erosive and accumulative landforms are not only very important for the analysis of the regional geomorphological process but also meaningful for the research on global change. According to the field investigation on the Quaternary geomorphology in the lower part of the Kanas Lake outlet in the main valley, this paper measured the altitude of multiple level U-shaped valley in different regions and confirmed the highest limit of glacial boulders and their spatial distribution. Using the electron spin resonance (ESR) method, we dated the glacial tills of the different moraines preserved along the main valley. Results of the glacial sequences, extent and glacial geomorphological process showed that four glacial advances occurred the lower part of the Kanas valley. Compared with the previous research results, these glaciations can be assigned as the Zhonglianggan glaciation, corresponding to the marine isotope stage 12 (MIS12), MIS8/10 glaciation, Penultimate glaciation (MIS6), and the last glacial cycle (LGC). LGC glacial advance can be further divided into three stages which correspond to MIS 4, 3, and 2. Based on the distribution of the three level U-shaped valleys, we concluded that the extent of glaciers decreased with time. The thickness of the glacier during Zhonglianggan glaciation was 50-395 m from the Glacial Station to the end of the glacier, and the length and width are also the largest at that time. The three-dimension extent showed that the glaciers were distributed in the main valley and on both sides of the ridges. The thickness was 102-199 m and 88-269 m during the MIS8/10 and the Penultimate glaciation, and the glacier reached near Tuojingwan. Well persevered multiple level U-shaped valley bottom on the eastern slope of the main valley near the region of Yazehu Lake indicated that the Quaternary glaciers have the warm glacier features such as strong activities, flowability and continuity. Clear asymmetry that occurred in the Kanas main valley showed that the development of the glacial valley was affected by regional climate and topography.

Key words: Altay Mountains, Kanas river valley, late Quaternary, glacial sequence, geomophological process

Wei ZHANG, Yanjing FU, Beibei LIU, Liang LIU, Zhijiu CUI, Yuanhuang SHI, Siwen WANG. Geomorphological process of late Quaternary glaciers in Kanas river valley of the Altay Mountains[J].Acta Geographica Sinica, 2015, 70(5): 739-750.

Figures/Tables 9

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References 56

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实验室号	野外编号	采样地点	经纬度坐标/N、E	海拔/m	物质	U	Th	K	含水量/%	年剂量/GY/Ka	古剂量/GY	年龄/Ka
14042	KE13-03	湖口滞碛	48°42'41.21"87°1'21.42"	1375	细砂	3.35	18.5	1.80	0.12	4.06	116±17	28±4
14043	KE13-04	冰水平原	48°41'21.82"87°0'42.02"	1380	细砂	5.12	45.9	1.68	0.18	6.35	518±120	81±18
14044	KE13-05	七级平台	48°41'31.54"87°3'23.75"	1615	细砂	4.24	18.9	1.66	0.10	4.18	916±184	219±44
14045	KE13-06	七级平台	48°41'31.15"87°3'0.13"	1575	细砂	3.72	15.7	2.20	0.06	4.33	332±71	76±16
14046	KE13-07	花楸谷	48°35'25.76"87°4'22.33"	1310	细砂	3.43	17.0	1.82	0.15	4.00	786±146	196±36

地区	测年地点	方法	年代/ka	MIS	来源
	白湖高侧碛垄	OSL	27.2±2.0 16.1±1.5	MIS2	[34]
	湖口第一组终碛垄	OSL ESR	28.2±3.3 28±4	MIS2 MIS4	[32] 本文
	湖口第二组终碛垄	OSL	34.3±4.2 38.1±4.5	MIS 3a	[32]
阿尔泰山		OSL	43.6±6.7 52.1±7.8	MIS 3	[33]
	湖口第三组终碛垄	OSL	49.9±5.4	MIS 3b	[32]
		OSL ESR	73.1±6.6 76±16	MIS 4	[33] 本文
	驼颈湾终碛垄花楸谷侧碛垄老图瓦村侧碛垄	ESR ESR ESR	125±12 156±15 196±36 219±44	MIS 6	[32] 本文
	蒙古阿尔泰山	TL	467±51	MIS12	[47]
天山	乌鲁木齐河河源	ESR	459.7 477.1 a	MIS12	[48]
	托木尔河	ESR	418.9±40.2	MIS12	[49]
	阿特奥依纳克河	ESR	453.0±45.3 440.6±41.7	MIS12	[36]
祁连山	摆浪河	ESR	462.9	MIS12	[50]
昆仑山	昆仑山垭口	ESR	710±228	MIS16	[51]

考察地点	编号	纬度(N)	经度(E)	高度(m)	宽度(m)	相对高度(m)	总厚度(m)
冰川站	A3	48°43' 49.79"	87°3' 24.67"	2165	5280	395	772
	A2	48°43' 44.18"	87°2' 56.89"	1770	4010	199
	A1	48°43' 32.39"	87°2' 22.80"	1571	3090	178
	A0	48°43' 17.23"	87°1' 48.89"	1393
七级台地	B3	48°42' 22.54"	87°3' 40.90"	2160		360	764
	B2	48°41' 1.37"	87°3' 44.40"	1800		135
	B1	48°41' 35.78"	87°3' 22.58"	1665		269
	B0	48°41' 35.39"	87°2' 4.12"	1396
鸭泽湖	C3	48°40' 9.77"	87°2' 42.14"	1862	4240	151	465
	C2	48°40' 14.74"	87°2' 32.86"	1711	3670	127
	C1	48°40' 15.28"	87°2' 9.02"	1584	2520	187
	C0	48°40' 11.14"	87°1' 42.28"	1397
卧龙湾	D3	48°37' 24.78"	87°3' 56.77"	1743	2560	68	373
	D2	48°37' 21.79"	87°3' 32.36"	1675	1890	115
	D1	48°37' 17.58"	87°3' 17.06"	1560	1250	190
	D0	48°37' 10.28"	87°3' 6.84"	1370
驼颈湾	E3	48°33' 24.73"	87°8' 49.85"	1450	1160	50	240
	E2	48°33' 22.68"	87°8' 45.71"	1400	945	102
	E1	48°33' 13.75"	87°8' 39.01"	1298	413	88
	E0	48°32' 58.08"	87°8' 45.85"	1210

Geomorphological process of late Quaternary glaciers in Kanas river valley of the Altay Mountains

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