CHRONOLOGY OF YICHANG GRAVEL LAYER BASED ON QUARTZ TI-LI CENTER ESR DATING AND ITS IMPLICATIONS FOR THE INCISION TIMING OF THE THREE GORGES VALLEY

doi:10.3969/j.issn.0253-4967.2020.01.005

Abstract

Abstract:

Uplift of Tibet Plateau and formation of Asian Monsoon greatly affect East Asian geomorphological evolution, climate change and environment systems. Thus, those phenomena also control the origin, size and direction of river systems. The Yangtze River, as the most important linkage between Tibet Plateau and the East Asian marginal seas, delivers large volumes of water, sediment, and associated chemicals from its headwater regions and tributaries to the East China Sea, significantly influencing sedimentary system evolution in its drainage basin. Therefore, the formation of the modern Yangtze River and its geological-time evolution history have been paid more and more attention to since the beginning of the last century. After debated for more than a century, the First Bend in Shigu area and the Three Gorges have been known as the key capture point of the Yangtze River’s evolution history. In particularly, the Three Gorges incision period remains greatly controversial, which mainly focuses on Cretaceous period-Neogene period, early Pleistocene period, and late Quaternary period.
The Yichang Gravel, just located downstream and outlet of the Three Gorges with an inverted triangle shape, is mainly distributed in western Jianghan Basin with over 1 000km². Because of its wide distribution and key geographical location, many typical profiles of Yichang Gravel have been the critical materials for studies on stratigraphic division, geomorphic evolution, and paleoenvironment change in middle Yangtze River Basin, especially on the Three Gorges incision history. Based on the previous field investigation, the Yichang gravel unconformably overlies the Cretaceous bedrocks and underlies the mid-Pleistocene vermicular red earth. In addition, studies on heavy mineral assemblages, Pb isotopic compositions of detrital K-feldspar grains, magnetic characteristics as well as pollen assemblage characteristics have showed that sediments in Yichang Gravel are mainly derived from upper Yangtze River Basin, such as Jinshangjiang drainage, Minjiang drainage, Jialingjiang drainage and Wujiang drainage. Based on the above comprehensive analysis, researchers demonstrated that the depositing time of Yichang Gravel can best constrain the Three Gorges incising time.
The absolute altitude of Yichang Gravel exceeds 110m, and many thick sand lens are developed from top to bottom of the profiles. In this study, we applied the quartz Ti-Li center ESR dating method in Yichang Gravel to determine its absolute formation age, and then to constrain the minimum cutting-through time of Three Gorges. Eight samples(SXY-1, SXY-2, YC-1—4, LJY-1, LJY-2)were collected from the sand lens at depths of 4m, 19m, 40m, 51m, 63m, 75m, 83m and 99m respectively from the top of the profile. At the same time, in order to evaluate the residual dose of Ti-Li center after sunlight bleaching, we also sampled four modern surface Yangtze River sediments near Yichang Gravel for ESR measurement.
The result shows that the quartz Ti-Li center ESR signal intensity of the 4 modern fluvial sediments samples are zero, which implies that the Ti-Li center ESR signal intensity of quartz in Yichang Gravel sand lens could be bleached to zero before the last burial. Thus, the above results indicate that the ESR dating results of this paper are reliable. The ESR absolute age from top to bottom of the profile is 0.73Ma BP,0.87Ma BP,0.98Ma BP,1.04Ma BP,1.05Ma BP,1.10Ma BP, 1.11Ma BP, 1.12Ma BP, respectively. The ESR dating results show that the Yichang Gravel began to deposit at about 1.12Ma BP until 0.73Ma BP, and the Ti-Li center ESR age indicates that the Yangtze River cut through Three Gorges area no later than 1.12Ma BP.

Key words: Jianghan Basin, Yichang Gravel Layer, quartz, Ti-Li center, ESR dating, Three Gorges valley incision

摘要：

江汉盆地是长江贯通三峡后的第一个卸载盆地。前人的研究表明堆积于江汉盆地西缘的宜昌砾石层是三峡贯通后的直接沉积地层, 因此, 宜昌砾石层堆积的下限年龄可为长江贯通三峡提供重要的年代约束。但传统的相对年代学方法研究在宜昌砾石层中难以取得较好的成果。因此, 直接对快速堆积的宜昌砾石层的形成年代和时间跨度开展年代学研究就需要寻找一种更可靠的绝对测年方法, 同时这也是现有研究中的一个重点和难点。据此, 文中在宜昌砾石层最具代表性的3个连续的沉积剖面上自上而下系统地采集了8个厚层砂质透镜体样品, 采用石英Ti-Li心ESR测年方法对其堆积年代和地层时代跨度进行研究。结果显示: 宜昌砾石层堆积的年代下限约1.12Ma BP, 上限约0.73Ma BP, 为早更新世晚期到中更新早期约0.4Ma的沉积层。结合前人的物源示踪结果, 分析认为至少在1.12Ma BP之前长江就已经贯通三峡。

关键词: 江汉盆地, 宜昌砾石层, 石英, Ti-Li心, ESR法测年, 三峡贯通

CLC Number:

P597

WEI Chuan-yi, LIU Chun-ru, LI Chang-an, YIN Gong-ming, HAN Fei, ZHANG Dai, LI Ya-wei, ZHANG Yu-fen. CHRONOLOGY OF YICHANG GRAVEL LAYER BASED ON QUARTZ TI-LI CENTER ESR DATING AND ITS IMPLICATIONS FOR THE INCISION TIMING OF THE THREE GORGES VALLEY[J]. SEISMOLOGY AND GEOLOGY, 2020, 42(1): 65-78.

魏传义, 刘春茹, 李长安, 尹功明, 韩非, 张岱, 李亚伟, 张玉芬. 宜昌砾石层石英Ti-Li心ESR年龄及其对三峡贯通时限的指示[J]. 地震地质, 2020, 42(1): 65-78.

Figures/Tables 6

Fig. 1 Location and distribution of Yichang Gravel, Jianghan Plain.

Fig. 2 Sketch map showing lithological column and sampling horizon position as well as pictures of the Yichang Gravel profile.

Fig. 3 ESR spectrum showing quartz Al center and Ti-Li center of natural sample observed at low temperature(liquid nitrogen, 77K).

Fig. 4 ESR spectrum showing quartz Al center and Ti-Li center of modern fluvial sediment in Yichang area of Yangtze River.

Fig. 5 Additional dose response curves of quartz Ti-Li center for the samples collected from Yichang Gravel, Jianghan Plain.

Table1 ESR dating result of quartz Ti-Li center in Yichang Gravel, Jianghan Plain

样品编号	埋深 /m	U	Th	K₂O /%	含水量 /%	环境剂量率 /Gy·ka^-1	等效剂量 /Gy	测年结果 /ka
SXY-2	4	2.32×10^-6	4.61×10^-6	1.78	8±5	3.04	2 230±555	734±183
SXY-1	19	1.33×10^-6	4.35×10^-6	1.68	8±5	2.55	2 206±281	865±110
YC-4	40	8.78×10^-7	5.82×10^-6	1.66	8±5	2.52	2 478±320	983±127
YC-3	51	1.05×10^-6	4.71×10^-6	1.56	8±5	2.37	2 472±364	1 043±154
YC-2	63	1.28×10^-6	4.69×10^-6	1.63	8±5	2.52	2 634±621	1 045±246
YC-1	75	9.44×10^-7	4.87×10^-6	1.51	8±5	2.30	2 527±389	1 098±169
LJY-2	83	1.08×10^-6	5.53×10^-6	1.37	8±5	2.29	2 531±330	1 105±144
LJY-1	99	1.52×10^-6	4.63×10^-6	1.62	8±5	2.60	2 919±362	1 123±139

References 44

[1]	康春国, 李长安, 王节涛, 等. 2009. 江汉平原沉积物重矿物特征及其对三峡贯通的指示[J]. 地球科学(中国地质大学学报), 34(3): 419—427. doi: 10.3321/j.issn: 1000-2383.2009.03.006.
	KANG Chun-guo, LI Chang-an, WANG Jie-tao, et al.2009. Heavy mineral characteristics of sediments in Jianghan Plain and its indication to the Three Gorges[J]. Earth Science(Journal of China University of Geosciences), 34(3): 419—427(in Chinese).
[2]	康春国, 李长安, 张玉芬, 等. 2014. 宜昌砾石层重矿物组合特征及物源示踪分析[J]. 地质学报, 88(2): 254—262. doi: 10.3969/j.issn.0001-5717.2014.02.008.
	KANG Chun-guo, LI Chang-an, ZHANG Yu-fen, et al.2014. Heavy mineral characteristics of the Yichang gravel layers and provenance tracing[J]. Acta Geologica Sinica, 88(2): 254—262(in Chinese).
[3]	李长安, 张玉芬. 1999. 一次重要的第四纪构造运动及环境效应[J]. 地质科技情报, 18(4): 42—46. doi: 10.3969/j.issn.1000-7849.1999.04.009.
	LI Chang-an, ZHANG Yu-fen.1999. An important tectonic movement and its environmental effect in Quaternary[J]. Geological Science and Technology Information, 18(4): 42—46(in Chinese).
[4]	李庭, 李长安, 康春国, 等. 2010. 宜昌砾石层的沉积环境及地貌意义[J]. 中国地质, 37(2): 438—445. doi: 10.3969/j.issn.1000-3657.2010.02.017.
	LI Ting, LI Chang-an, KANG Chun-guo, et al.2010. Sedimentary environment and geomorphological significance of the gravel bed in Yichang[J]. Geology in China, 37(2): 438—445(in Chinese).
[5]	李文朋, 刘春茹, 牛东伟, 等. 2018. 怀来盆地珠窝堡遗址ESR年代学初步研究[J]. 第四纪研究, 38(3): 680—687. doi: 10.11928/j.issn.1001-7410.2018.03.12.
	LI Wen-peng, LIU Chun-ru, NIU Dong-wei, et al.2018. Electron spin resonance data of the Zhuwobao paleolithic site in the Huailai Basin of China[J]. Quaternary Sciences, 38(3): 680—687(in Chinese).
[6]	刘春茹, 尹功明, 高璐, 等. 2009. 泥河湾盆地东坡遗址ESR年代学初步研究[J]. 第四纪研究, 29(1): 166—172.
	LIU Chun-ru, YIN Gong-ming, GAO Lu, et al.2009. ESR dating of Dongpo paleolithic site in the Nihewan Basin of China[J]. Quaternary Sciences, 29(1): 166—172(in Chinese).
[7]	刘春茹, 尹功明, 高璐, 等. 2011. 第四纪沉积物 ESR 年代学研究进展[J]. 地震地质, 33(2): 490—498. doi: 10.3969/j.issn.0253-4967.2011.02.022.
	LIU Chun-ru, YIN Gong-ming, GAO Lu, et al.2011. Research advances in ESR geochronology of Quaternary deposits[J]. Seismology and Geology, 33(2): 490—498(in Chinese).
[8]	刘春茹, 尹功明, 韩非, 等. 2016. 石英ESR测年法在第四纪陆相沉积物测年中的应用[J]. 第四纪研究, 36(5): 1236—1245. doi: 10.11928/j.issn.1001-7410.2016.05.18.
	LIU Chun-ru, YIN Gong-ming, HAN Fei, et al.2016. ESR dating methodology and its application in dating Quaternary terrestrial sediments[J]. Quaternary Sciences, 36(5): 1236—1245(in Chinese).
[9]	王萍, 李建平, 王建存, 等. 2011. 四川昔格达组地层的石英Ti心ESR测年及与磁性地层剖面的对比[J]. 核技术, 34(2): 111—115.
	WANG Ping, LI Jian-ping, WANG Jian-cun, et al.2011. Quartz Ti-center in ESR dating of Xigeda formation in Sichuan and contrast with magnetic stratigraphic profiles[J]. Nuclear Techniques, 34(2): 111—115(in Chinese).
[10]	魏传义, 刘春茹, 李长安, 等. 2018. 石英不同Ti-Li心电子自旋共振信号光晒退特征及其测年意义[J]. 地球环境学报, 9(6): 607—613. doi: 10.7515/JEE182053.
	WEI Chuan-yi, LIU Chun-ru, LI Chang-an, et al.2018. Bleaching characteristics of quartz electron spin resonance(ESR)signals of multiple Ti-Li centers: Implication for ESR dating[J]. Journal of Earth Environment, 9(6): 607—613(in Chinese).
[11]	向芳. 2004. 长江三峡的贯通与江汉盆地西缘及邻区的沉积响应 [D]. 成都: 成都理工大学.
	XIANG Fang.2004. Forming of the Three Gorges of the Yangtze River and sedimentary response in the west edge of Jianghan Basin and adjacent area [D]. Chengdu University of Technology, Chengdu(in Chinese).
[12]	向芳, 王成善, 李国忠, 等. 2006a. 宜昌地区第四纪沉积物重矿物特征及其与三峡贯通的关系[J]. 成都理工大学学报(自然科学版), 33(2): 117—121. doi: 10.3969/j.issn.1671-9727.2006.02.002.
	XIANG Fang, WANG Cheng-shan, LI Guo-zhong, et al.2006a. Character of heavy minerals in Quaternary sediments in Yichang area and its relationship with cut-through of the Yangtze Three Gorges, China[J]. Journal of Chengdu University of Technology(Science and Technology Edition), 33(2): 117—121(in Chinese).
[13]	向芳, 杨栋, 田馨, 等. 2011. 湖北宜昌地区第四纪沉积物中锆石的U-Pb年龄特征及其物源意义[J]. 矿物岩石, 31(2): 106—114. doi: 10.3969/j.issn.1001-6872.2011.02.015.
	XIANG Fang, YANG Dong, TIAN Xin, et al.2011. LA-ICP-MS U-Pb geochronology of zircons in the Quaternary sediments from the Yichang area of Hubei Province and its provenance significance[J]. Journal of Mineral Petrol, 31(2): 106—114(in Chinese).
[14]	向芳, 朱利东, 王成善, 等. 2006b. 宜昌地区第四纪沉积物中玄武岩砾石特征及其与长江三峡贯通的关系[J]. 地球科学与环境学报, 28(2): 6—10. doi: 10.3969/j.issn.1672-6561.2006.02.002.
	XIANG Fang, ZHU Li-dong, WANG Cheng-shan, et al.2006b. Character of basaltic gravels in Quaternary sediments in Yichang area and its relationship with formation of Yangtze Three Gorges[J]. Journal of Earth and Environment, 28(2): 6—10(in Chinese).
[15]	张勇, 张玉芬, 李长安, 等. 2009. 宜昌地区砾石层的磁性特征与物源分析[J]. 第四纪研究, 29(2): 380—386. doi: 1001-7410(2009)-380-07.
	ZHANG Yong, ZHANG Yu-fen, LI Chang-an, et al.2009. Magnetic properties of the gravel layers in Yichang area and their provenance[J]. Quaternary Sciences, 29(2): 380—386(in Chinese).
[16]	张玉芬, 李长安, 周稠, 等. 2014. 长江中游高位砾石层的磁性特征与物源分析[J]. 吉林大学学报(地球科学版), 44(5): 1669—1677. doi: 10.13278/j.cnki.jjuese.201405301.
	ZHANG Yu-fen, LI Chang-an, ZHOU Chou, et al.2014. Magnetism and provenance analysis of high position gravel layer in the middle reaches of Yangtze River[J]. Journal of Jilin University(Earth Science Edition), 44(5): 1669—1677(in Chinese).
[17]	张增杰. 2016. 长江水系晚新生代沉积物碎屑钾长石Pb同位素组成 [D]. 武汉: 中国地质大学.
	ZHANG Zeng-jie.2016. Pb isotopic compositions of detrital K-feldspar grains of the late Cenozoic sediments from the Yangtze River system [D]. China University of Geosciences, Wuhan(in Chinese).
[18]	赵诚. 1996. 长江三峡河流袭夺与河流起源[J]. 长春地质学院学报, 26(4): 428—433.
	ZHAO Cheng.1996. River capture and origin of the Yangtze Gorges[J]. Journal of Changchun University of Earth Sciences, 26(4): 428—433(in Chinese).
[19]	赵诚, 王世梅. 2000. 长江三峡及其上游河流袭夺新认识[J]. 武汉水利电力大学(宜昌)学报, 22(3): 196—199. doi: 10.3969/j.issn.1672-948X.2000.03.003.
	ZHAO Cheng, WANG Shi-mei.2000. New recognition of river capture in Three Gorges and its upper reaches[J]. Journal of University of Hydraulic and Electric Engineering(Yichang), 22(3): 196—199(in Chinese).
[20]	Aitken M J.1998. An Introduction to Optical Dating [M]. London, Oxford University Press: 39—44.
[21]	Beerten K, Stesmans A.2006. The use of Ti centers for estimating burial doses of single quartz grains: A case study from an aeolian deposit~2Ma old[J]. Radiation Measurements, 41(4): 418—424. doi: 10.1016/j.radmeas.2005.10.004.
[22]	Beerten K, Stesmans A.2007. ESR dating of sedimentary quartz: Possibilities and limitations of the single-grain approach[J]. Quaternary Geochronology, 2(1): 373—380. doi: 10.1016/j.quageo.2006.03.003.
[23]	Bridgland D R, Westaway R.2014. Quaternary fluvial archives and landscape evolution: A global synthesis[J]. Proceedings of the Geologists Association, 125(5-6): 600—629. doi: 10.1016/j.pgeola.2014.10.009.
[24]	Clark M K, Schoenbohm L M, Royden L H, et al.2004. Surface uplift, tectonics, and erosion of eastern Tibet from large-scale drainage patterns[J]. Tectonics, 23(1): TC1006. doi: 10.1029/2002tc001402.
[25]	Clift P D, Carter A, Campbell I H, et al.2013. Thermochronology of mineral grains in the Red and Mekong Rivers, Vietnam: Provenance and exhumation implications for Southeast Asia[J]. Geochemistry Geophysics Geosystems, 7(10): 123—129. doi: 10.1029/2006gc001336.
[26]	Duval M, Arnold L J, Guilarte V, et al.2017. Electron spin resonance dating of optically bleached quartz grains from the Middle Palaeolithic site of Cuesta de la Bajada(Spain)using the multiple centres approach[J]. Quaternary Geochronology, 37:82—96. doi: 10.1016/j.quageo.2016.09.006.
[27]	Gu J, Chen J, Sun Q, et al.2014. China’s Yangtze delta: Geochemical fingerprints reflecting river connection to the sea[J]. Geomorphology, 227:166—173. doi: 10.1016/j.geomorph.2014.05.015.
[28]	Liu C R, Grün R.2011. Fluvio-mechanical resetting of the Al and Ti centres in quartz[J]. Radiation Measurements, 46(10): 1038—1042. doi: 10.1016/j.radmeas.2011.06.076.
[29]	Liu C R, Yin G M, Deng C L, et al.2014. ESR dating of the Majuangou and Banshan Paleolithic sites in the Nihewan Basin, North China[J]. Journal of Human Evolution, 73(4): 58—63. doi: 10.1016/j.jhevol.2014.05.012.
[30]	Liu C R, Yin G M, Gao L, et al.2010. ESR dating of Pleistocene archaeological localities of the Nihewan Basin, North China: Preliminary results[J]. Quaternary Geochronology, 5(2): 385—390. doi: 10.1016/j.quageo.2009.05.006.
[31]	Liu C R, Yin G M, Gao L, et al.2013a. ESR dating of the Donggutuo Palaeolithic site in the Nihewan Basin, northern China[J]. Geochronometria, 40(4): 348—354. doi: 10.2478/s13386-013-0127-4.
[32]	Liu C R, Yin G M, Han F.2015. Effects of grain size on quartz ESR dating of Ti-Li center in fluvial and lacustrine sediments[J]. Quaternary Geochronology, 30(2): 513—518. doi: 10.1016/j.quageo.2015.02.007.
[33]	Liu C R, Yin G M, Zhang H P, et al.2013b. ESR geochronology of the Minjiang River terraces at Wenchuan, eastern margin of Tibetan plateau, China[J]. Geochronometria, 40(4): 360—367. doi: 10.2478/s13386-013-0129-2.
[34]	Parton A, Farrant A R, Leng M J, et al.2015. Alluvial fan records from southeast Arabia reveal multiple windows for human dispersal[J]. Geology, 43(4): 295—298. doi: 10.1130/G36401.1.
[35]	Richardson N J, Densmore A L, Seward D, et al.2010. Did incision of the Three Gorges begin in the Eocene?REPLY[J]. Geology, 38(6): 551—554. doi: 10.1130/G30527.1.
[36]	Rink W J, Bartoll J, Schwarcz H P, et al.2007. Testing the reliability of ESR dating of optically exposed buried quartz sediments[J]. Radiation Measurements, 42(10): 1618—1626. doi: 10.1016/j.radmeas.2007.09.005.
[37]	Tissoux H, Toyoda S, Falguères C, et al.2008. ESR dating of sedimentary quartz from two Pleistocene deposits using Al and Ti-centers[J]. Geochronometria, 30(1): 23—31. doi: 10.2478/v10003-008-0004-y.
[38]	Toyoda S, Hattori W.2000. Formation and decay of the E’center and of its precursor[J]. Applied Radiation and Isotopes, 52(5): 1351—1356. doi: 10.1016/S0969-8043(00)00094-4.
[39]	Voinchet P, Falguères C, Tissoux H, et al.2007. ESR dating of fluvial quartz: Estimate of the minimal distance transport required for getting a maximum optical bleaching[J]. Quaternary Geochronology, 2(1): 363—366. doi: 10.1016/j.quageo.2006.04.010.
[40]	Wang P, Zheng H B, Chen L, et al.2014. Exhumation of the Huangling anticline in the Three Gorges region: Cenozoic sedimentary record from the western Jianghan Basin, China[J]. Basin Research, 26(4): 505—522. doi: 10.1111/bre.12047.
[41]	Xiang F, Du W, Huang H, et al.2018. Provenance study of Fe-Ti oxide minerals in the Quaternary sediments in Yichang area and its implication of formation time of the Yangtze Three Gorges, China[J]. Acta Geologica Sinica(English Edition), 92(4): 1598—1608.
[42]	Xiang F, Zhu L D, Wang C S, et al.2007. Quaternary sediment in the Yichang area: Implications for the formation of the Three Gorges of the Yangtze River[J]. Geomorphology, 85(3): 249—258. doi: 10.1016/j.geomorph.2006.03.027.
[43]	Yang S, Li C, Yokoyama K.2006. Elemental compositions and monazite age patterns of core sediments in the Changjiang Delta: Implications for sediment provenance and development history of the Changjiang River[J]. Earth and Planetary Science Letters, 245(3-4): 762—776. doi: 10.1016/j.epsl.2006.03.042.
[44]	Zheng H B, Clift P D, Wang P, et al.2013. Pre-Miocene birth of the Yangtze River[J]. Proceedings of the National Academy of Sciences of the United States of America, 110(19): 7556—7561. doi: 10.1073/pnas.1216241110.