OSL Ages Revealing the Glacier Retreat in the Dangzi Valley in the Eastern Tibetan Plateau During the Last Glacial Maximum

Quaternary Geochronology 10 (2012) 244e249

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Research paper OSL ages revealing the glacier retreat in the Dangzi valley in the eastern Tibetan Plateau during the Last Glacial Maximum

Biao Zhang a,b,d, XianJiao Ou b,c, ZhongPing Lai a,b,* a Luminescence Dating Group, Qinghai Institute of Salt Lakes, CAS, 18 XinNing Rd, Xining 810008, China b State Key laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China c School of Geography and Tourism, Jiaying University, Meizhou 514015, China d Graduate University of Chinese Academy of Sciences, Beijing 100049, China article info abstract

Article history: Mountain glaciers are highly sensitive to temperature and precipitation fluctuations and, thus, the Received 14 October 2011 deposits of glacier growth and retreat constrain climatic variables. The Dangzi valley, located on the Received in revised form northern slope of Queer Shan Mountain, eastern Tibetan Plateau, is influenced by Indian monsoon and 19 January 2012 has preserved four integrated sets of moraines and associated glacial sediments. Numerical ages are Accepted 21 January 2012 scarce in this area, even though the moraines have been investigated for decades. In this study, dating of Available online 30 January 2012 the glacial tills and glaciofluvial deposits was undertaken using quartz optically stimulated luminescence (OSL). We conclude that: (1) OSL ages show good agreement with geomorphological features. The Keywords: OSL dating samples should have been well-bleached before deposition, otherwise it is rather impossibly that all the Moraines ages in the former three sets are overestimated to a similar degree due to poor beaching as the spatial Last Glacial Maximum (LGM) and temporal dynamics vary within glaciated valley. (2) Mountain glaciers have reached the maximum Dangzi valley extent at about 25e22 ka in Dangzi valley during the Last Glacial Maximum (LGM). Then the glaciers Eastern Tibetan Plateau retreated several times and formed the last terminal moraine at about 16.5 ka, which may indicate the termination of LGM on the eastern Tibetan Plateau. (3) The age of DZ307 (54.0 4.7 ka) demonstrates that the glacial advance also occurred at Marine Isotope Stage (MIS) 3, and that the glacial advance was larger in MIS 3 than in LGM, which is in agreement with previous results in the adjacent Yingpu valley. (4) The glacial evolution during the LGM in the study area was possibly controlled by the temperature changes, which could response to the summer solar insolation in northern hemisphere. Ó 2012 Elsevier B.V. All rights reserved.

1. Introduction on the range of glaciation on the Tibetan Plateau due to poor http://ir.isl.ac.cnchronological data (Kuhle, 1988, 1995; Zheng, 1989; Zheng and The Tibetan Plateau and the bordering mountains contain many Rutter, 1998). Within the last decade, two new techniques have glaciers outside of the Polar Regions, and extensive glacial sedi- promised to remedy this situation. The application of optically ments for past glaciations are still well preserved. These glacial stimulated luminescence (OSL) and terrestrial cosmogenic radio- deposits are particularly helpful for reconstructing palaeoclimate nuclide (TCN) methods has expanded the number of chronologies because mountain glaciers are dependent on regional climate as throughout the Tibetan Plateau and determined the timing and well as global condition and extremely sensitive to environmental style of glaciation in some key areas on the Tibetan Plateau and change (Derbyshire et al., 1991; Shi, 1992; Gillespie and Molnar, adjacent areas (Richards et al., 2000; Spencer and Owen, 2004; 1995; Owen et al., 2009). The use of glacial sediments as palae- Owen et al., 2008; Schäfer et al., 2008; Lai et al., 2009; Zhao oenvironmental proxy requires a temporal framework. During the et al., 2009; Xu et al., 2009, 2010; Ou et al., 2010). past several decades, relative dating methods, such as the use of As an important component of a broad scientiﬁcefforttounder- morphostratigraphy and relative weathering have been widely stand the Earth’s surface during the Last Glacial Maximum (LGM) used (Li and Su, 1996; Shi, 2006). Nevertheless, different views exist (CLIMAP Project Members,1981), the timing and style duringthe LGM glaciation on the Tibetan Plateau is still poorly deﬁned (Lehmkuhl et al., 1998; Schäfer et al., 2002; Owen et al., 2002). Owen et al. * Corresponding author. Luminescence Dating Group, Qinghai Institute of Salt (2008) have recently assessed that the glacial advances in MIS 2 Lakes, CAS, 18 XinNing Rd, Xining 810008, China. Tel.: þ86 (0) 971 6330670; were less extensive than those in MIS 3. Schäfer et al. (2006) sug- fax: þ86 (0) 971 6336002. E-mail address: [email protected] (ZhongPing Lai). gested that large-scale retreats of mid-latitude LGM glaciers

1871-1014/$ e see front matter Ó 2012 Elsevier B.V. All rights reserved. doi:10.1016/j.quageo.2012.01.013 B. Zhang et al. / Quaternary Geochronology 10 (2012) 244e249 245 commenced at about the same time in both hemispheres. However, defined sets of terminal moraines are preserved with an average the evolution of any history of the mountain glaciers on the Tibetan height of 3e7 m in the outer and inner parts of the Dangzi valley at Plateau during the LGM is still an open question. Moreover, the an altitude of 3985e3866 m asl (Fig. 2). Boulders, some of which are responses of glacial activity to climate change at the LGM have extremely large, scattered widely across the surface of these remained perplexing. The key point to solve this question is to find out moraines and between the four sets. Evidence for the first set suitable terminal moraine sequences that document high frequency comprises only a single prominent terminal moraine that are glacial fluctuation at the LGM. In this study, we obtained new data closely linked and located near the outlet of Dangzi Lake. This about glacial history at the LGM using OSL for the eastern margin of moraine was influenced by river incising, so that it can be clearly the Tibetan Plateau. Our discussion is based on the combination of seen that glaciofluvial sediments were deposited near the terminal geomorphological relationship, OSL chronologyand reconstruction of moraine. Moraines of the second set occur within 1e1.5 km of the former ice extents from well-preserved terminal moraines. lake outlet including three arc-like end moraines. The tills of the third set are w4 km down away from the lake outlet and display 2. Study area closely clustered moraines containing a set of four prominent ridges. The outer most terminal moraine set, which includes two The study area, the Dangzi valley, is situated in the northern moraines, marks the maximum extent of the Dangzi valley glaciers, margin of Queer Shan Mountain, which belongs to the Hengduan about 8 km far from the cliff closed to the Dangzi Lake. The fourth Mountains on the eastern margin of the Tibetan Plateau (Fig. 1a and set was covered by loess, and tills and boulders in this set show b). In the northern slope of the Queer Shan, modern glaciers have much greater degree of weathering than that of the former three developed at the high altitude with the equilibrium-line altitude sets, suggesting that it is possibly older. (ELA) at about 5200 m asl. The Dangzi valley is adjacent to the The climate of the region is relatively warm and humid, strongly Yingpu and Langlong valley. It reaches the southern margin of the influenced by the south Asia monsoon in the summer, which Zhuqing basin from the northern slope of the Queer Shan (Fig. 1c). provides most of the annual precipitation of typically more than The Dangzi valley is an NNWeSSE trending U-shaped valley with 600 mm, and the mid-latitude westerlies in the winter (Shi, 2006). a length of 8 km and is between 3900 and 4200 m asl. The Dangzi An early survey and mapping of the area was carried by Li and Su River originates from the northern slopes of Queer Shan and flows (1996). Li and Su (1996) assessed the past glacial advances along northwards through the Duoji lake and Dangzi lake eventually into Dangzi valley into the two stages, using the relative dating methods the Yalongjiang River. From the upper part of the valley, Dangzi based on morphostratigraphy and relative weathering criteria. The Lake, with a distance about 6.5 km from the headwall, was eroded three sets in the head part were assigned to be the last ice age, and by glacial advance and then glacier melt water was accumulated the tail set was attributed to the penultimate glaciation. Glacial due to terminal moraines damming. advances during the last glacial period in the Dangzi valley were The valley is flat and wide, which implies that this valley could supported by a TL age (24.7 2 ka) obtained from the most outside be the ideal area for the preservation of glacial evolution. Four well- set of moraine in the Dangzi valley (Lehmkuhl et al., 1998).

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Fig. 1. (a) Shuttle Radar Topography Mission (SRTM) DEM image of the Tibetan Plateau. (b) Main mountains and rivers in the Hengduanshan region. (c) The location of Dangzi valley in the Zhuqing basin. 246 B. Zhang et al. / Quaternary Geochronology 10 (2012) 244e249

Fig. 2. The geomorphic map of Dangzi valley and the sampling sites. The OSL ages are showed in each site. Bold lines of different colours across the Dangzi valley are remnant of end moraine.

According to several OSL and ESR results from the moraines in determined using a combination of the single aliquot regenerative- Yingpu valley, Xu et al. (2010) suggested that glacial advances were dose (SAR) protocol (Murray and Wintle, 2000) and standardized significantly less extensive in the global LGM than that in the MIS 3 growth curve (SGC) method (Roberts and Duller, 2004; Lai and in this study area. Wintle, 2006; Lai et al., 2007). Fig. 3a shows typical quartz OSL decay curves of natural dose (N), test dose (TD ¼ 11.1 Gy) and 3. Dating method and results regeneration doses for sample DZ301, and Fig. 3b a growth curve. The recycling ratios are consistent with unity for all samples. All the 3.1. OSL sampling (L0/T0)/(LN/TN) ratios are low, indicating that the effect of thermal transfer is negligible (Rhodes and Pownall, 1994; Rhodes and Six samples were collected by hammering stainless steel tubes Bailey, 1997; Rhodes, 2000). All samples show similar behaviors. into cleaned deposits from six sites along the Dangzi valley (Fig. 2). The combined preheat plateau and dose recovery test were used The tubes were covered and sealed by black plastic bag, and then to choose a suitable preheat temperature and evaluate the suit- wrapped using plastic bag and tape to avoid light exposure and ability of SAR protocol (Murray and Wintle, 2003). The test was moisture loss. Fig. 2 provides details of the sample locations and conducted on sample DZ301（Fig. 2def). The preheat temperature geomorphic settings. Samples (DZ301, DZ303 and DZ305) are of 260 C was chosen for the SAR measurement. All doses recovery supra-glacial melt-out tills on the top of moraine ridges. DZ302 and are within 10% acceptance limit (Wintle and Murray, 2006; Spencer DZ304 are glaciofluvial sediments, but the former one was depos- and Robinson, 2008), indicating that experimental parameters of ited by outwash of terminal moraine and the latter one was formed SAR measurements are appropriate for Dangzi valley samples. For by micro-environment in the in-board part of the terminal each sample, 6e8 aliquots were measured by SAR to determine De, moraine. DZ307 is from glacial tills in the outmost set of moraines and then 12e18 additional aliquots were measured for De deter- where the tills are buried by loess. mination using SGC. The SGC De is in agreement with SAR De. Therefore, the final De for a sample is the average of both SAR De 3.2. Laboratory analysis and the SGC De. Radionuclide activity concentrations were estimated from uranium, thorium and potassium concentrations OSL sample preparation followed the procedures of Lai and measured by neutron activation analysis (NAA). An estimate of Wintle (2006) and Lai (2010). Samples were treated with 10% HCl 10 5% water content was adopted. The cosmic ray dose rate was and 30% H2O2 to remove carbonates and organics, respectively. The estimated for each sample as a function of depth, altitude and quartz fraction of the grains withhttp://ir.isl.ac.cn a diameter of 38e63 mmwas geomagnetic latitude (Prescott and Hutton, 1994). separated by wet sieving and then treated with 35% fluorosilicic acid (H2SiF6) for about two weeks (Berger et al., 1980; Lai et al., 3.3. Results 2007). After infra-red light checking, samples that showed obvious infra-red stimulated luminescence (IRSL) signals were The OSL ages are shown in Fig. 2 and listed in Table S1. DZ301 retreated with H2SiF6 to avoid age underestimation (Lai et al., (16.5 1.3 ka) and DZ302 (16.3 1.3 ka) are younger than DZ303 2008). Pure quartz could be extracted from 3 samples (DZ301, (24.7 2.0 ka), DZ304 (20.7 1.8 ka) and DZ305 (22.4 2.2 ka), DZ302, and DZ307), the other 3 samples (DZ303, DZ304, and which reveals the different time interval of glacial advance during DZ305) still showed distinct IRSL. The problem is likely due to the MIS2. DZ307 (54.0 4.7 ka) demonstrates that a glacial advance feldspar inclusions (Huntley et al., 1993). Finally quartz grains (pure occurred during MIS 3, suggesting that the glacial advance was or not) were deposited on an area of 0.5 cm diameter on 1.0 cm larger in MIS 3 than in LGM, which is in agreement with previous diameter stainless steel discs using silicone oil. results in the adjacent Yingpu valley (Xu et al., 2010). On the whole, Experiments were performed using a Risø TL-DA-20 reader. the OSL ages are in stratigraphic order, and are consistent with the Stimulation used blue LEDs (l ¼ 470 20 nm) for 40 s at 130 C and geological setting, weathering and cementation of the moraines. the OSL signal was detected by a 9235QA photomultiplier tube through a 7.5 mm thick Hoya U-340 detection filter. As the 4. Discussion measurements of pure quartz grains were made using blue light stimulation at 130 C for 40 s. The not-pure quartz discs were Glacigenic sediments present considerable difficulties for OSL stimulated by infrared stimulation for 100 s at 0 C before blue light dating due to poor bleaching (Duller, 1994, 2006). As a result, gla- stimulation (using double-SAR protocol by Banerjee et al., 2001; ciofluvial sediments (DZ302 and DZ304) should be better-bleached and Roberts and Wintle, 2001). Equivalent doses (De)were than the tills (DZ301, DZ303, DZ305 and DZ307). Tills may be partial B. Zhang et al. / Quaternary Geochronology 10 (2012) 244e249 247

Fig. 3. Luminescence characteristics forhttp://ir.isl.ac.cn sample DZ301. (a) Decay curves. (b) Growth curve. (c) The histogram of De distribution. (d) Preheat plateau. (e) Recuperation ratio. (f) Recycling ratio. bleaching owing to shorter daylight exposure during transport and Processes of the Ice age: Land, Oceans, Glaciers) at ‘Chronozone deposition (Tsukamoto et al., 2002; Duller, 2008; Fuchs and Owen, Level 2’, between 18 and 24 ka (Mix et al., 2001). However, on the 2008; Thrasher et al., 2009). However, supraglacial tills are easier to Tibetan Plateau, it appears that glacial retreat was delayed until reset because they are transported on the surface of glacier 18e16 ka in response to the continued supply of moisture to (Richards et al., 2000; Tsukamoto et al., 2002). Potential of quartz mountain glaciers until 17.5 ka (Clark et al., 2009). We suggest that OSL dating using SAR protocol on moraine deposits in the Yingpu the well-defined moraines in the Dangzi valley at 25e16 ka broadly valley closed to the Dangzi valley has been discussed by Ou et al. fit the timing of glacial advance and retreat during the LGM on the (2010). As the spatial and temporal dynamics vary within glaci- Tibetan Plateau. In the U-shaped valley, each set of terminal ated valley, it is rather impossibly that all the ages in the former moraines marks the maximum extent of glacial advance at one three sets are overestimated to a similar degree due to poor time. These four sets of moraines, deposited at successive positions beaching. Alternative resetting mechanisms is also possible for of the margin during the LGM of progressive glaciers retreat, are fluvial samples (Liu and Grün, 2011), which requires further recessional moraines. This style shows the Dangzi valley glaciers research. The clustering of OSL dates suggests that the dated reached the maximum extent at about 25e22 ka and then retreated moraines represent glacial expansion during the last glacial period. several times and formed the last set of moraines at about 16 ka. The OSL ages indicate that the four sets of moraines in the U-shaped Mountain glaciers can only exist under a specific range of climatic valley formed during 25e16 ka. The definition of the LGM used here conditions and are extremely sensitive to environmental change, is that recommended by the EPILOG project (Environmental notably changes in temperature and precipitation (Owen et al., 248 B. Zhang et al. / Quaternary Geochronology 10 (2012) 244e249

2009). Owen et al. (2008) identified that glacial advance during the Duller, G.A.T., 1994. Luminescence dating of poorly bleached sediments from e LGM on the Tibetan plateau is mainly influenced by temperature. Scotland. Quaternary Science Reviews 13, 521 524. Duller, G.A.T., 2006. Single grain optical dating of glacigenic deposits. Quaternary A global summer temperature warming initiated the mid-latitude Geochronology 1, 296e304. glacial retreat at the end of the LGM (17.5 ka) (Schäfer et al., 2006). Duller, G.A.T., 2008. Single-grain optical dating of Quaternary sediments: why e The former three sets in the Dangzi valley reflect high frequency of aliquot size matters in luminescence dating. Boreas 37, 589 612. fl Fuchs, M., Owen, L.A., 2008. Luminescence dating of glacial and associated sedi- glacial uctuations, and possibly respond to the temperature change ments: review, recommendations and future directions. Boreas 37, 636e659. at the LGM. Even if multiple factors, such as albedo, elevation, and Gillespie, A., Molnar, P., 1995. Asynchronous maximum advances of mountain and atmospheric greenhouse gas concentrations, control temperature continental glaciers. Reviews of Geophysics 33, 311e364. Huntley, D.J., Hutton, J.T., Prescott, J.R., 1993. Optical dating using inclusions within change, the northern latitude insolation is the only factor as the quartz grains. Geology 21, 1087e1090. primary trigger mechanism for increasing temperature and forcing Kuhle, M., 1988. The Pleistocene glaciation of Tibet and the onset of ice ages: an the onset of northern hemisphere deglaciation (at 19e20 ka) (Clark autocycle hypothesis. GeoJournal 17 (4), 581e596. Kuhle, M., 1995. Glacial isostatic uplift of Tibet as a consequence of a former ice et al., 2009). As discussed above, we can infer that after the Dangzi sheet. GeoJournal 37, 431e449. valley glaciers reached their maximum extent at about 25e22 ka, Lai, Z.P., Wintle, A.G., 2006. Locating the boundary between the Pleistocene and the several recessional moraines were formed later due to an increase Holocene in Chinese loess using luminescence. The Holocene 16, 893e899. in northern summer insolation. The innermost moraines (16.5 ka) Lai, Z.P., Brückner, H., Zöller, L., Fülling, A., 2007. Existence of a common growth curve for silt-sized quartz OSL of loess from different continents. Radiation show the onset of the termination of the LGM. Measurements 42, 1432e1440. Lai, Z.P., Zöller, L., Fuchs, M., Brückner, H., 2008. Alpha efficiency determination for OSL of quartz extracted from Chinese loess. Radiation Measurements 43, 767e770. 5. Conclusions Lai, Z.P., Kaiser, K., Brückner, H., 2009. Luminescence dated aeolian deposits of late quaternary age in the southern Tibetan Plateau and their implications for In this study, six OSL samples were collected from moraines in landscape history. Quaternary Research 72, 421e430. Lai, Z.P., 2010. Chronology and the upper dating limit for loess samples from Luo- Danzi valley in the east Tibetan Plateau to test the suitability of OSL chuan section in Chinese Loess Plateau using quartz OSL SAR protocol. Journal dating of glacial sediments and then to establish the chronology. of Asian Earth Sciences 37, 176e185. We conclude that: (1) OSL results show a good agreement with Lehmkuhl, F., Owen, L.A., Derbyshire, E., 1998. Late Quaternary glacial history of northeastern Tibet. Quaternary Proceedings 6, 121e142. geomorphological features. The samples should have been well- Li, J.J., Su, Z., 1996. Glaciers in the Hengduan Mountains. Science Press, Beijing (in bleached before deposition, otherwise it is rather impossibly that all Chinese with English abstract). the ages in the former three sets are overestimated to a similar degree Liu, C.R., Grün, R., 2011. Fluvio-mechanical resetting of the Al and Ti centres in e due to poor beaching as the spatial and temporal dynamics vary quartz. Radiation Measurements 46, 1038 1042. Mix, A.C., Bard, E., Schneider, R., 2001. Environmental processes of the ice age: land, within glaciated valley. (2) Mountain glaciers have reached the oceans, glaciers (EPILOG). Quaternary Science Reviews 20, 627e657. maximum extent at about 25e22 ka in Dangzi valley during the LGM. Murray, A.S., Wintle, A.G., 2000. Luminescence dating of quartz using an improved e Then the glaciers retreated several times and formed the last terminal single-aliquot regenerative-dose protocol. Radiation Measurements 32, 57 73. Murray, A.S., Wintle, A.G., 2003. The single aliquot regeneration dose protocol: moraine at about 16.5 ka, which may indicate the termination of LGM potential for improvements in reliability. Radiation Measurements 37, 377e381. on the eastern Tibetan Plateau. (3) DZ307 (54.0 4.7 ka) demon- Ou, X.J., Xu, L.B., Lai, Z.P., Long, H., He, Z., Fan, Q.S., Zhou, S.Z., 2010. Potential of strates that a glacial advance also occurred at MIS 3, suggesting that quartz OSL dating on morainic deposits from eastern Tibetan Plateau using SAR protocol. Quaternary Geochronology 5, 257e262. glacial advances may have been larger in MIS 3 than at the LGM, which Owen, L.A., Finkel, R.C., Caffee, M.W., 2002. A note on the extent of glaciation is in agreement with previous results in the adjacent Yingpu valley throughout the Himalaya during the global Last Glacial Maximum. Quaternary (Xu et al., 2010). (4) The glacial evolution during the LGM in the study Science Reviews 21, 147e157. Owen, L.A., Caffee, M.W., Finkel, R.C., Seong, B.S., 2008. Quaternary glaciation of the areawas possiblycontrolled by the temperature changes, which could HimalayaneTibetan orogen. Journal of Quaternary Science 23, 513e532. response to the summer solar insolation in northern hemisphere. Owen, L.A., Thackray, G., Anderson, R.S., Briner, J., Kaufman, D., Roe, G., Pfeffer, W., Yi, C.L., 2009. Integrated research on mountain glaciers: current status, priori- ties and future prospects. Geomorphology 103, 158e171. Acknowledgements Prescott, J.R., Hutton, J.T., 1994. Cosmic ray contributions to dose rates for luminescence and ESR dating: large depths and long-term time variations. Radiation e We thank DongFeng Niu, Rong Chen and JiangLong Wang for Measurements 23, 497 500. Rhodes, E.J., Pownall, L., 1994. Zeroing of the OSL signal in quartz from young gla- help in the field, and Rainer Grün for helpful comments. This study ciofluvial sediments. Radiation Measurements 23, 581e585. is supported by the National Natural Sciences Foundation of China Rhodes, E.J., Bailey, R.M., 1997. The effect of thermal transfer on the zeroing of the fl (grants 40901011 and 41172168) andhttp://ir.isl.ac.cn One-Hundred Talents Project luminescence of quartz from recent glacio uvial sediments. Quaternary Science Reviews 16, 291e298. of the Chinese Academy of Sciences granted to ZPL (A0961). Rhodes, E.J., 2000. Observations of thermal transfer OSL signals in glacigenic quartz. Editorial Handling by: R. Grun Radiation Measurements 32, 595e602. Richards, B.W.M., Owen, L.A., Rhodes, E.J., 2000. Timing of Late Quaternary glaciations in the Himalayas of northern Pakistan. Journal of Quaternary Science 15, 283e297. Appendix. Supplementary material Roberts, H.M., Wintle, A.G., 2001. Equivalent dose determinations for polymineralic fine-grains using the SAR protocol: application to a Holocene sequence of the Chinese Loess Plateau. Quaternary Science Reviews 20, 859e863. Supplementary material associated with this article can be Roberts, H.M., Duller, G.A.T., 2004. Standardised growth curves for optical dating of found, in the online version, at doi:10.1016/j.quageo.2012.01.013. sediment using multiple-grain aliquots. Radiation Measurements 38, 241e252. Schäfer, J.M., Tschudi, S., Zhao, Z.Z., Wu, X., Ivy-Ochs, S., Wieler, R., Baur, H., Kubik, P.W., Schluchter, C., 2002. The limited influence of glaciation in Tibet on References global climate over the past 170,000 yr. Earth and Planetary Science Letters 194, 287e297. Banerjee, D., Murray, A.S., Bøtter-Jensen, L., Lang, A., 2001. Equivalent dose esti- Schäfer, J.M., Denton, G.H., Barrell, D.J.A., Ivy-Ochs, S., Kubik, P.W., Andersen, B.G., mation using a single aliquot of polymineral fine grains. Radiation Measure- Phillips, F., Lowell, T.V., Schluechter, C., 2006. Near-synchronous interhemi- ments 33, 73e93. spheric termination of the Last Glacial Maximum in mid-latitudes. Science 312, Berger, G.W., Mulhern, P.J., Huntley, D.J., 1980. Isolation of silt-sized quartz from 1510e1513. sediments. Ancient TL 11, 8e9. Schäfer, J.M., Oberholzer, P., Zhao, Z., Ivy-Ochs, S., Wieler, R., Baur, H., Kubik, P.W., Clark, P.U., Dyke, A.S., Shakun, J.D., Carlson, A.E., Clark, J., Wohlfarth, B., Schluchter, C., 2008. Cosmogenic beryllium-10 and neon-21 dating of late Mitrovica, J.X., Hostetler, S.W., McCabe, M.M., 2009. The Last Glacial Maximum. Pleistocene glaciations in Nyalam, monsoonal Himalayas. Quaternary Science Science 325, 710e714. Reviews 27, 295e311. CLIMAP, 1981. Seasonal Reconstruction of the Earth’s Surface at the Last Glacial Shi, Y., 1992. Glaciers and glacial geomorphology in China. Zeitschrift Fǜr Geo- Maximum. In: Geological Society of America, Map and Chart Series, vol. C36. morphologie 86, 19e35. Derbyshire, E., Shi, Y., Li, J., Zheng, B.X., Li, S., Wang, J., 1991. Quaternary glaciation of Shi, Y., 2006. The Quaternary Glaciations and Environmental Variations in China. Tibet: the geological evidence. Quaternary Science Reviews 10, 485e510. Hebei Science and Technology, Shijiazhuang (in Chinese with English abstract). B. Zhang et al. / Quaternary Geochronology 10 (2012) 244e249 249

Spencer, J.Q., Owen, L.A., 2004. Optically stimulated luminescence dating of Late Xu, L.B., Ou, X.J., Lai, Z.P., Zhou, S.Z., Wang, J., Fu, Y.C., 2010. Timing and style of Late Quaternary glaciogenic sediments in the upper Hunza valley: validating the Pleistocene glaciation in the Queer Shan, northern Hengduan Mountains in the timing of glaciation and assessing dating methods. Quaternary Science Reviews eastern Tibetan Plateau. Journal of Quaternary Science 25, 957e966. 23, 175e191. Xu, X.K., Yang, J.Q., Dong, G.C., Wang, L.Q., Miller, L., 2009. OSL dating of glacier Spencer, J.Q.G., Robinson, R.A.J., 2008. Dating intramontane alluvial deposits from extent during the Last Glacial and the Kanas Lake basin formation in Kanas NW Argentina using luminescence techniques: problems and potential. River valley, Altai Mountains, China. Geomorphology 112, 306e317. Geomorphology 93, 144e155. Zhao, J.D., Liu, S.Y., He, Y.Q., Song, Y.G., 2009. Quaternary glacial chronology of the Thrasher, I.M., Mauz, B., Chiverrell, R.C., Lang, A., 2009. Luminescence dating of Ateaoyinake River Valley, Tianshan Mountains, China. Geomorphology 103, glacio-ﬂuvial deposits: a review. Earth Science Reviews 97, 133e146. 276e284. Tsukamoto, S., Asahi, K., Watanabe, T., Rink, W.J., 2002. Timing of past glaciations in Zheng, B.X., 1989. Controversy regarding the existence of a large ice sheet on the Kanchenjunga Himal, Nepal by optically stimulated luminescence dating of tills. QinghaieXizang (Tibetan) Plateau during the Quaternary period. Quaternary Quaternary International 97e98, 57e67. Research 32, 121e123. Wintle, A.G., Murray, A.S., 2006. A review of quartz optically stimulated lumines- Zheng, B., Rutter, N., 1998. On the problem of Quaternary Glaciations, and the extent cence characteristics and their relevance in single-aliquot regeneration dating and patterns of Pleistocene ice cover in the QinghaieXizang (Tibet) Plateau. protocols. Radiation Measurements 41, 369e391. Quaternary International 45/46, 109e122.

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