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Fig. 7. Field photograph showing a soil pit dug into a beach ridge shoreline of the G2 group. Deposits are characterized by well-sorted, rounded gravel and cobble clasts with interbedded sand lenses. OSL sample (018, see location in Fig. 5a) show in position.

Figure 7 Field photograph showing a soil pit dug into a beach ridge shoreline of the G2 group. Deposits are characterized by well-sorted, rounded gravel and cobble clasts with interbedded sand lenses. OSL sample (018, see location in Fig. 5a) show in position.

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Fig. 1. Google Earth satellite image showing the locations of major lakes in closed basins in the Tibetan Plateau. The red numbers labeled next to the lake names refer to previous studies of Tibetan lakes mentioned in the text: 1-Gu et al., 1993; 2-Kashiwaya et al., 1995; 3-Rades et al., 2013; 4-Rades et al., 2015; 5-Ahlborn et al., 2016; 6-Chen et al., 2013; 7- Hudson et al., 2015; 8-Huth et al., 2015; 9-Gasse et al., 1996; 10-Liu et al., 2016; 11-Kong et al., 2007; 12-Miigler et al., 2010; 13-Li et al., 2011; 14-Bird et al., 2014; 15-Shen et al., 2008; 16-Herzschuh et al., 2006. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Fig. 1. Google Earth satellite image showing the locations of major lakes in closed basins in the Tibetan Plateau. The red numbers labeled next to the lake names refer to previous studies of Tibetan lakes mentioned in the text: 1-Gu et al., 1993; 2-Kashiwaya et al., 1995; 3-Rades et al., 2013; 4-Rades et al., 2015; 5-Ahlborn et al., 2016; 6-Chen et al., 2013; 7- Hudson et al., 2015; 8-Huth et al., 2015; 9-Gasse et al., 1996; 10-Liu et al., 2016; 11-Kong et al., 2007; 12-Miigler et al., 2010; 13-Li et al., 2011; 14-Bird et al., 2014; 15-Shen et al., 2008; 16-Herzschuh et al., 2006. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Fig. 2. Present-day hydrologic system of the Siling Co basin. (a) The map showing the lake distribution within the drainage basin and major rivers flowing to Siling Co and Nam Co. (b) Photograph of shoreline groups developed on the NE promontory of the central peninsula of Siling Co.
Fig. 2. Present-day hydrologic system of the Siling Co basin. (a) The map showing the lake distribution within the drainage basin and major rivers flowing to Siling Co and Nam Co. (b) Photograph of shoreline groups developed on the NE promontory of the central peninsula of Siling Co.
Fig. 3. The map showing that the shorelines around Siling Co are characterized by six clusters at different elevation ranges.
Fig. 3. The map showing that the shorelines around Siling Co are characterized by six clusters at different elevation ranges.
Fig. 4. The geomorphology and topography of clustered shoreline features in southwestern Siling Co (see location in Fig. 3). (a) Clustered shoreline features similar to those in the central peninsula, atop the Google Earth imagery. (b) The topographic profile of the lower parts of the shoreline features (see profile location in Fig. 4a).
Fig. 4. The geomorphology and topography of clustered shoreline features in southwestern Siling Co (see location in Fig. 3). (a) Clustered shoreline features similar to those in the central peninsula, atop the Google Earth imagery. (b) The topographic profile of the lower parts of the shoreline features (see profile location in Fig. 4a).
Fig. 5. Topographic and geomorphic features of shorelines and alluvial fans developed on the central peninsula of Siling Co. (a) GeoEye image (nominal resolution of 0.5 m) showing the shoreline features (white lines) and OSL sample locations. Ages are shown with 2-sigma uncertainties. (b) Topographic profiles of shoreline elevations in the central peninsula (black lines, see locations in Fig. 5a and c) and southwest of Siling Co (red line, see profile location in Fig. 4a). (c) Close-up of GeoEye image showing the shorelines and alluvial fans developed along the Tashi Stream (see location in Fig. 5a). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Fig. 5. Topographic and geomorphic features of shorelines and alluvial fans developed on the central peninsula of Siling Co. (a) GeoEye image (nominal resolution of 0.5 m) showing the shoreline features (white lines) and OSL sample locations. Ages are shown with 2-sigma uncertainties. (b) Topographic profiles of shoreline elevations in the central peninsula (black lines, see locations in Fig. 5a and c) and southwest of Siling Co (red line, see profile location in Fig. 4a). (c) Close-up of GeoEye image showing the shorelines and alluvial fans developed along the Tashi Stream (see location in Fig. 5a). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
6. Field photos (a—b) and sketch (c) of stratigraphic relations above the G2 shorelines along the Tashi Stream. At this location, samples 041 and 010 were collected from the ch deposits and alluvial sand layer, respectively. A close view of the sample 010 site is shown in panel (a).
6. Field photos (a—b) and sketch (c) of stratigraphic relations above the G2 shorelines along the Tashi Stream. At this location, samples 041 and 010 were collected from the ch deposits and alluvial sand layer, respectively. A close view of the sample 010 site is shown in panel (a).
Fig. 8. Radial plots showing distributions of equivalent dose (D.) and uncertainties of OSL samples from this study. Note that the open circles in the radial plots fall outside of the 2- standard estimate range and are therefore differentiated from the data points that fall within that range, but they are included in the analysis.
Fig. 8. Radial plots showing distributions of equivalent dose (D.) and uncertainties of OSL samples from this study. Note that the open circles in the radial plots fall outside of the 2- standard estimate range and are therefore differentiated from the data points that fall within that range, but they are included in the analysis.
ig. 9. Reconstructed changes in lake level and surface area of Siling Co and Gyaring Co during the Holocene. (a) Map showing lake surface area of the Siling Co and Gyaring Co at 4 tillstands (corresponding to groups G6, G5, G2, and G1). Map was determined by taking surveyed elevations and determining their position from the 90-m-resolution Shuttle Radai opographic Mission (SRTM) topographic data. The lake area of Siling Co in 1976 has been provided in Meng et al. (2012a), and elevation of the highstand level at Gyaring Co is from hi et al. (2014). (b) Shoreline elevations vs. corresponding OSL ages from highstand and recessional deposits. Color code of the circles are the same as those in Fig. 9a. (c) Change in ike surface area through time. The black dot shows the contribution of lake area change from Gyaring Co. The red line shows the possible area change path, inferred from the lake -vel change on the left. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
ig. 9. Reconstructed changes in lake level and surface area of Siling Co and Gyaring Co during the Holocene. (a) Map showing lake surface area of the Siling Co and Gyaring Co at 4 tillstands (corresponding to groups G6, G5, G2, and G1). Map was determined by taking surveyed elevations and determining their position from the 90-m-resolution Shuttle Radai opographic Mission (SRTM) topographic data. The lake area of Siling Co in 1976 has been provided in Meng et al. (2012a), and elevation of the highstand level at Gyaring Co is from hi et al. (2014). (b) Shoreline elevations vs. corresponding OSL ages from highstand and recessional deposits. Color code of the circles are the same as those in Fig. 9a. (c) Change in ike surface area through time. The black dot shows the contribution of lake area change from Gyaring Co. The red line shows the possible area change path, inferred from the lake -vel change on the left. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
OSL sample data for recessional shorelines below the Lingtong lake highstand. * N is the number of aliquots used for OSL analysis. > CAM — central age model; MAM — minimum age model; numbers denote the component of each age model. © Position denotes the depositional environment of the samples. A — samples in the alluvial sediments; B — samples in the top layers of the beach ridge: Table 1
OSL sample data for recessional shorelines below the Lingtong lake highstand. * N is the number of aliquots used for OSL analysis. > CAM — central age model; MAM — minimum age model; numbers denote the component of each age model. © Position denotes the depositional environment of the samples. A — samples in the alluvial sediments; B — samples in the top layers of the beach ridge: Table 1
Fig. 10. Comparison of the lake level change of Siling Co with other lake level curves and lake core proxies from the Tibetan Plateau. (a) Lake level changes of Siling Co (also see details in the captions of Fig. 9b). The circles show OSL ages from shoreline deposits, with the same color codes as Fig. 9b. The thick red lines are lake level change suggested by our data; solid and dashed red lines show well-determined and inferred lake levels, respectively. The gray dashed line shows the lake history inferred from the carbonate 5'80 record of Siling Co (see Fig. 10b). The light pink bars show approximate time periods of rapid lake recession. (b) Carbonate 8'80 records of Siling Co (Gu et al., 1993). (c) Shoreline-derived lake level changes for lakes in western Tibet: Longmu Co (Liu et al., 2016), Ngangla Ring Co (Hudson et al., 2015), Baqan Co (Huth et al., 2015), Zhari Namco (Chen et al., 2013). The green dashed line represents our interpretation of possible stepwise recession of Tangra Yumco based on newly published shoreline data (Ahiborn et al., 2016) and the ‘outlier’ data in previous studies (Rades et al., 2013, 2015). (d) Grain size index of Paru Co suggesting changes in lake depth through time (Bird et al., 2014). (e—g) Pollen records from Nam Co (Miigler et al., 2010), Zigetang Co (Herzschuh et al., 2006) and Co Ngion (Shen et al., 2008), respectively. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Fig. 10. Comparison of the lake level change of Siling Co with other lake level curves and lake core proxies from the Tibetan Plateau. (a) Lake level changes of Siling Co (also see details in the captions of Fig. 9b). The circles show OSL ages from shoreline deposits, with the same color codes as Fig. 9b. The thick red lines are lake level change suggested by our data; solid and dashed red lines show well-determined and inferred lake levels, respectively. The gray dashed line shows the lake history inferred from the carbonate 5'80 record of Siling Co (see Fig. 10b). The light pink bars show approximate time periods of rapid lake recession. (b) Carbonate 8'80 records of Siling Co (Gu et al., 1993). (c) Shoreline-derived lake level changes for lakes in western Tibet: Longmu Co (Liu et al., 2016), Ngangla Ring Co (Hudson et al., 2015), Baqan Co (Huth et al., 2015), Zhari Namco (Chen et al., 2013). The green dashed line represents our interpretation of possible stepwise recession of Tangra Yumco based on newly published shoreline data (Ahiborn et al., 2016) and the ‘outlier’ data in previous studies (Rades et al., 2013, 2015). (d) Grain size index of Paru Co suggesting changes in lake depth through time (Bird et al., 2014). (e—g) Pollen records from Nam Co (Miigler et al., 2010), Zigetang Co (Herzschuh et al., 2006) and Co Ngion (Shen et al., 2008), respectively. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Fig. 11. Comparison of lake level changes of Siling Co with paleoclimatic proxies suggesting changes in the strength of the Asian monsoon. (a) Lake level changes at Siling Co, same as shown in Fig. 8a. (b) Mn/Ti ratios from Lake Rara, Nepalese Himalaya (Nakamura et al., 2016). (c—d) 3'80 records from speleothems in Tianmen Cave in central Tibet (Cai et al., 2012) (see location in Fig. 1) and Dongge Cave (Wang et al., 2005) in east China, respectively. (e) Insolation change at 30°N (Berger, 1978). (f) Upwelling record (relative abundance of G. bulloides) from the Arabian Sea (Gupta et al., 2003). (g) Changes in dolomite concentration in the Gulf of Oman (Cullen et al., 2000). (h) 3Dwax record from biomarkers in Lake Challa, east Africa (Tierney et al., 2011). (i) Changes of percentage of hematite-stained grains in the North Atlantic (Bond et al., 2001).
Fig. 11. Comparison of lake level changes of Siling Co with paleoclimatic proxies suggesting changes in the strength of the Asian monsoon. (a) Lake level changes at Siling Co, same as shown in Fig. 8a. (b) Mn/Ti ratios from Lake Rara, Nepalese Himalaya (Nakamura et al., 2016). (c—d) 3'80 records from speleothems in Tianmen Cave in central Tibet (Cai et al., 2012) (see location in Fig. 1) and Dongge Cave (Wang et al., 2005) in east China, respectively. (e) Insolation change at 30°N (Berger, 1978). (f) Upwelling record (relative abundance of G. bulloides) from the Arabian Sea (Gupta et al., 2003). (g) Changes in dolomite concentration in the Gulf of Oman (Cullen et al., 2000). (h) 3Dwax record from biomarkers in Lake Challa, east Africa (Tierney et al., 2011). (i) Changes of percentage of hematite-stained grains in the North Atlantic (Bond et al., 2001).
References Appendix A. Supplementary data grant from the Tectonics program (EAR-0911587) to E.K. and K.P.F. Additional support to E.W. was provided by grants from the Chinese Academy of Sciences (XDB03010500). X.S. also thanks the support from the Earth Observatory of Singapore, Nanyang Technological University through its funding from the National Research Foun- dation Singapore and the Singapore Ministry of Education under the Research Centers of Excellence initiative. This work comprises Earth Observatory of Singapore contribution number 158. We are grateful to Tashi Wangdi and Feng Qu for assistance with the field work. Dr. Xianfeng Wang provided some feedbacks on an early version of the manuscript. We thank Editor Ana Moreno for the editorial handling of this paper, and thank Adam Hudson and one anonymous reviewer for providing constructive comments that helped improve the quality of this paper. We declare no financial interests among the authors. Supporting data can be accessed in the Supporting Material file.
References Appendix A. Supplementary data grant from the Tectonics program (EAR-0911587) to E.K. and K.P.F. Additional support to E.W. was provided by grants from the Chinese Academy of Sciences (XDB03010500). X.S. also thanks the support from the Earth Observatory of Singapore, Nanyang Technological University through its funding from the National Research Foun- dation Singapore and the Singapore Ministry of Education under the Research Centers of Excellence initiative. This work comprises Earth Observatory of Singapore contribution number 158. We are grateful to Tashi Wangdi and Feng Qu for assistance with the field work. Dr. Xianfeng Wang provided some feedbacks on an early version of the manuscript. We thank Editor Ana Moreno for the editorial handling of this paper, and thank Adam Hudson and one anonymous reviewer for providing constructive comments that helped improve the quality of this paper. We declare no financial interests among the authors. Supporting data can be accessed in the Supporting Material file.
Related topics:
Earth SciencesGeologyHistory and archaeologyAsian monsoonQuaternary Science ReviewsPunctuated Equilibrium
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