@article {2729,
	title = {Asian summer monsoon influence on chemical weathering and sediment provenance determined by clay mineral analysis from the Indus Submarine Canyon},
	journal = {Quaternary Research},
	volume = {93},
	year = {2020},
	month = {Jan-01-2020},
	pages = {23 - 39},
	abstract = {Clay minerals from the Indus Canyon and eastern clinoform since ~12 ka are uniformly rich in smectite and illite, similar to those from the Holocene Indus flood plains. A systematic enrichment of smectite in the proximal delta compared to the canyon and eastern clinoform argues for preferential capture of smectite close to the river mouth since ~12 ka. There is a rapid shift to a more smectite-rich assemblage in the canyon and eastern clinoform after ~5 ka. This change is probably caused by a change in sediment source, with less direct flux from the Himalaya and more erosion of older, weathered, smectite-rich sediment from the Indus River flood plains, driven by incision of the Indus and its tributaries into the floodplain as summer monsoon rains weakened. This influx of smectite is consistent with lower kaolinite/smectite values since ~5 ka. The onset of large-scale agricultural activities since ~5 ka, especially starting with the Harappan Civilization, may also have enhanced incision and erosion of floodplain sediments over the same time period. This study reports for the first time how monsoon strength variations since ~12 ka affected the clay mineral assemblages and sediment provenance in a major submarine canyon.},
	keywords = {Clay minerals, Holocene, monsoon, Provenance, Reworking, Submarine canyon},
	issn = {0033-5894},
	doi = {10.1017/qua.2019.44},
	url = {https://www.cambridge.org/core/journals/quaternary-research/article/asian-summer-monsoon-influence-on-chemical-weathering-and-sediment-provenance-determined-by-clay-mineral-analysis-from-the-indus-submarine-canyon/AA11F458BD5924C1BD9EC9901D1F2941},
	author = {Li, Yuting and Clift, Peter D. and Murray, Richard W. and Exnicios, Elise and Ireland, Thomas and B{\"o}ning, Philipp}
}
@article {2728,
	title = {Sea-level, monsoonal, and anthropogenic impacts on the millennial-scale variability of siliciclastic sediment input into the western Philippine sea since 27 ka},
	journal = {Journal of Asian Earth Sciences},
	volume = {177},
	year = {2019},
	month = {Jan-06-2019},
	pages = {250 - 262},
	abstract = {Multiproxy records from Core MD06-3054 in the western Philippine Sea and published results from the nearby Core MD06-3052, which are both located at the northern margin of the Western Pacific Warm Pool (WPWP), provide precise reconstructions and evidence for the potential controls on continental erosion and weathering intensities in Luzon. These data also constrain sediment source-to-sink processes in the sea since 27 ka at the millennial scale. We demonstrate that the siliciclastic fraction is derived from Luzon volcanic rocks and eolian dust from mainland Asia. Stronger physical erosion and chemical weathering generally occurred during the last glaciation, Heinrich Event 1, the Younger Dryas, and the period from 10.3 to 11.3 ka. In contrast, the B{\o}lling-Aller{\o}d was characterized by weaker physical erosion and chemical weathering. During the last glaciation, Heinrich Event 1, and the Younger Dryas, the lower sea level led to enhanced erosion and weathering of the exposed shelf sediments. In contrast, the weaker physical erosion and chemical weathering that occurred during the B{\o}lling-Aller{\o}d and the Holocene, except after 2.1 ka, are closely correlated with the higher sea level. The stronger physical erosion and chemical weathering at 10.3{\textendash}11.3 ka may be derived from the reworking of older sediments during the time of a strengthening summer monsoon. Furthermore, enhanced human activity since 2.1 ka has become the dominant control on erosion in Luzon. Rapid weathering changes in the WPWP during the last deglaciation highlight the high variability in local controls at low latitudes during these periods and the potential influence of controls at high latitudes.},
	issn = {13679120},
	doi = {10.1016/j.jseaes.2019.04.001},
	url = {https://www.sciencedirect.com/science/article/abs/pii/S1367912019301506},
	author = {Xu, Zhaokai and Li, Tiegang and Clift, Peter D. and Wan, Shiming and Lim, Dhongil and Chang, Fengming and Sun, Rongtao}
}
@article {2730,
	title = {Bathyal records of enhanced silicate erosion and weathering on the exposed Luzon shelf during glacial lowstands and their significance for atmospheric CO2 sink},
	journal = {Chemical Geology},
	volume = {476},
	year = {2018},
	month = {Jan-01-2018},
	pages = {302 - 315},
	abstract = {We present a new high-resolution multiproxy data set of mass accumulation rates, Sr-Nd isotopes, as well as major and trace elements for the siliciclastic sediment fraction from International Marine Global Change Study Core MD06-3052, located on the continental slope of the western Philippine Sea. We integrate our new data with published grain sizes and sea surface temperatures from the same core, as well as with Equatorial Pacific sea level, and East Asian summer monsoon precipitation, in order to constrain at high-resolution changes in physical erosion and chemical weathering intensities on Luzon, and sediment source-to-sink processes. We assess the potential significance of chemical weathering of arc silicates in regulating global atmospheric CO2 since 156 kyr BP. Sr-Nd isotopes show that the siliciclastic sediments were dominantly sourced from volcanic rocks exposed on Luzon (~ 68{\textendash}100\%), with a lesser contribution from Asian dust (~ 0{\textendash}32\%). Different indices indicate that stronger physical erosion and chemical weathering occurred during Marine Isotope Stage (MIS) 6 (130{\textendash}156 kyr BP), as well as in the latter stage of MIS 3 and MIS 2 (14{\textendash}40 kyr BP). The large sea-level lowstands and associated significant exposure of continental shelf in the western Philippine Sea during these two cold periods should favor physical erosion and chemical weathering of unconsolidated sediments on the exposed shelf. Furthermore, we notice the relatively good coherence between chemical weathering intensities on Luzon and global atmospheric CO2 concentrations over these cold intervals. We suggest that strengthening of chemical weathering of silicates on Luzon and other tropical arcs (within 20{\textdegree} of the Equator) during the Quaternary glacial sea-level lowstands may significantly contribute to the lowering of atmospheric CO2 concentrations during ice ages. We estimate that a significant fraction, up to ~ 16\% (i.e., ~ 8 ppmv), of all atmospheric CO2 ultimately sequestered by silicate weathering may be processed through an area corresponding to only ~ 1\% of the exorheic drainage area worldwide.},
	keywords = {Atmospheric CO2 concentration, Chemical weathering, East Asian summer monsoon, sea level, Western Philippine Sea},
	issn = {00092541},
	doi = {10.1016/j.chemgeo.2017.11.027},
	url = {https://www.sciencedirect.com/science/article/pii/S0009254117306587},
	author = {Xu, Zhaokai and Li, Tiegang and Clift, Peter D. and Wan, Shiming and Qiu, Xiaohua and Lim, Dhongil}
}
@article {2727,
	title = {On the Holocene evolution of the Ayeyawady megadelta},
	journal = {Earth Surface Dynamics},
	volume = {6},
	year = {2018},
	month = {Jan-01-2018},
	pages = {451 - 466},
	abstract = {The Ayeyawady delta is the last Asian megadelta whose evolution has remained essentially unexplored so far. Unlike most other deltas across the world, the Ayeyawady has not yet been affected by dam construction, providing a unique view on largely natural deltaic processes benefiting from abundant sediment loads affected by tectonics and monsoon hydroclimate. To alleviate the information gap and provide a baseline for future work, here we provide a first model for the Holocene development of this megadelta based on drill core sediments collected in 2016 and 2017, dated with radiocarbon and optically stimulated luminescence, together with a reevaluation of published maps, charts and scientific literature. Altogether, these data indicate that Ayeyawady is a mud-dominated delta with tidal and wave influences. The sediment-rich Ayeyawady River built meander belt alluvial ridges with avulsive characters. A more advanced coast in the western half of the delta (i.e., the Pathein lobe) was probably favored by the more western location of the early course of the river. Radiogenic isotopic fingerprinting of the sediment suggests that the Pathein lobe coast does not receive significant sediment from neighboring rivers. However, the eastern region of the delta (i.e., Yangon lobe) is offset inland and extends east into the mudflats of the Sittaung estuary. Wave-built beach ridge construction during the late Holocene, similar to several other deltas across the Indian monsoon domain, suggests a common climatic control on monsoonal delta morphodynamics through variability in discharge, changes in wave climate or both. Correlation of the delta morphological and stratigraphic architecture information on land with the shelf bathymetry, as well as its tectonic, sedimentary and hydrodynamic characteristics, provides insight on the peculiar growth style of the Ayeyawady delta. The offset between the western Pathein lobe and the eastern deltaic coast appears to be driven by tectonic{\textendash}hydrodynamic feedbacks as the extensionally lowered shelf block of the Gulf of Mottama amplifies tidal currents relative to the western part of the shelf. This situation probably activates a perennial shear front between the two regions that acts as a leaky energy fence. Just as importantly, the strong currents in the Gulf of Mottama act as an offshore-directed tidal pump that helps build the deep mid-shelf Mottama clinoform with mixed sediments from the Ayeyawady, Sittaung and Thanlwin rivers. The highly energetic tidal, wind and wave regime of the northern Andaman Sea thus exports most sediment offshore despite the large load of the Ayeyawady River.},
	doi = {10.5194/esurf-6-451-201810.5194/esurf-6-451-2018-supplement},
	url = {https://esurf.copernicus.org/articles/6/451/2018},
	author = {Giosan, Liviu and Naing, Thet and Min Tun, Myo and Clift, Peter D. and Filip, Florin and Constantinescu, Stefan and Khonde, Nitesh and Blusztajn, Jerzy and Buylaert, Jan-Pieter and Stevens, Thomas and Thwin, Swe}
}
@article {2731,
	title = {Rapid precipitation changes in the tropical West Pacific linked to North Atlantic climate forcing during the last deglaciation},
	journal = {Quaternary Science Reviews},
	volume = {197},
	year = {2018},
	month = {Jan-10-2018},
	pages = {288 - 306},
	abstract = {The cause of rapid hydrological changes in the tropical West Pacific during the last deglaciation remains controversial. In order to test whether these changes were triggered by abrupt climate change events in the North Atlantic Ocean, variations in precipitation during the last deglaciation (18-10 ka) were extracted from proxy records of chemical weathering and terrigenous input in the western Philippine Sea (WPS). The evolution of chemical weathering and terrigenous input since 27 ka was reconstructed using the chemical index of alteration (CIA), elemental ratios (K/Al, TOC/TN and Ti/Ca), δ13Corg, terrigenous fraction abundance and flux data from International Marine Global Change Study Program (IMAGES) core MD06-3054 collected on the upper continental slope of eastern Luzon (northern Philippines). Sediment deposited during the Last Glacial Maximum (LGM) shows weathering equal to or slightly greater than Holocene sediment in the WPS. This unusual state of chemical weathering, which is inconsistent with lower air temperatures and decreased precipitation in Luzon during the LGM, may be due to reworking of poorly consolidated sediments on the eastern Luzon continental shelf during the LGM sea-level lowstand. Rapid changes in chemical weathering, characterized by higher intensity during the Heinrich event 1 (H1) and Younger Dryas (YD) and lower intensity during the B{\o}lling-Aller{\o}d (B/A), were linked to rapid variations in precipitation in the WPS during the last deglaciation. The higher terrigenous inputs during the LGM relative to those of the Holocene were controlled by sea-level changes rather than precipitation. The terrigenous inputs show a long-term decline during the last deglaciation, punctuated by brief spikes during the H1 and YD related to sea-level rises and rapid precipitation changes in the WPS, respectively. The proxy records of chemical weathering and terrigenous input from eastern Luzon suggest high rainfall during the H1 and YD events, consistent with inferred rainfall patterns based on Fe/Ca records from offshore Mindanao. Rapid precipitation changes in the WPS did not coincide with migrations of the Intertropical Convergence Zone (ITCZ) but, rather, were related to state shifts of the El Ni{\~n}o-Southern Oscillation (ENSO) during the last deglaciation. Based on proxy records and modeling results, we argue that the Atlantic meridional overturning circulation (AMOC) controlled rapid precipitation changes in the tropical West Pacific through zonal shifts of ENSO or meridional migration of the ITCZ during the last deglaciation. Our findings highlight the dominant role of the North Atlantic Ocean in the tropical hydrologic cycle during the last deglaciation. },
	keywords = {AMOC, Chemical weathering, enso, ITCZ, Terrigenous input, Western Philippine Sea},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2018.07.040},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0277379117309484https://api.elsevier.com/content/article/PII:S0277379117309484?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0277379117309484?httpAccept=text/plain},
	author = {Xiong, Zhifang and Li, Tiegang and Chang, Fengming and Algeo, Thomas J. and Clift, Peter D. and Bretschneider, Lisa and Lu, Zhengyao and Zhu, Xiao and Frank, Martin and Sauer, Peter E. and Jiang, FuQing and Wan, Shiming and Zhang, Xu and Chen, Shuangxi and Huang, Jie}
}
@article {148,
	title = {Chemical weathering and provenance evolution of Holocene{\textendash}Recent sediments from the Western Indus Shelf, Northern Arabian Sea inferred from physical and mineralogical properties},
	journal = {Marine Geology},
	volume = {326{\textendash}328},
	year = {2012},
	note = {id: 2271},
	pages = {101-115},
	abstract = {We present a multi-proxy mineral record based on X-ray diffraction and diffuse reflectance spectrophotometry analysis for two cores from the western Indus Shelf in order to reconstruct changing weathering intensities, sediment transport, and provenance variations since 13 ka. Core Indus-10 is located northwest of the Indus Canyon and exhibits fluctuations in smectite/(illite + chlorite) ratios that correlate with monsoon intensity. Higher smectite/(illite + chlorite) and lower illite crystallinity, normally associated with stronger weathering, peaked during the Early{\textendash}Mid Holocene, the period of maximum summer monsoon. Hematite/goethite and magnetic susceptibility do not show clear co-variation, although they both increase at Indus-10 after 10 ka, as the monsoon weakened. At Indus-23, located on a clinoform just west of the canyon, hematite/goethite increased during a period of monsoon strengthening from 10 to 8 ka, consistent with increased seasonality and/or reworking of sediment deposited prior to or during the glacial maximum. After 2 ka terrigenous sediment accumulation rates in both cores increased together with redness and hematite/goethite, which we attribute to widespread cultivation of the floodplain triggering reworking, especially after 200 years ago. Over Holocene timescales sediment composition and mineralogy in two localities on the high-energy shelf were controlled by varying degrees of reworking, as well as climatically modulated chemical weathering.},
	issn = {0025-3227},
	doi = {10.1016/j.margeo.2012.07.009},
	url = {http://www.sciencedirect.com/science/article/pii/S0025322712001600},
	author = {Limmer, David R. and K{\"o}hler, Cornelia M. and Hillier, Stephen and Moreton, Steven G. and Tabrez, Ali R. and Clift, Peter D.}
}
@article {166,
	title = {Clay mineral variations in Holocene terrestrial sediments from the Indus Basin},
	journal = {Quaternary Research},
	volume = {77},
	year = {2012},
	note = {id: 2333},
	pages = {368-381},
	abstract = {We employed X-ray diffraction methods to quantify clay mineral assemblages in the Indus Delta and flood plains since ~ 14 ka, spanning a period of strong climatic change. Assemblages are dominated by smectite and illite, with minor chlorite and kaolinite. Delta sediments integrate clays from across the basin and show increasing smectite input between 13 and 7.5 ka, indicating stronger chemical weathering as the summer monsoon intensified. Changes in clay mineralogy postdate changes in climate by 5{\textendash}3 ka, reflecting the time needed for new clay minerals to form and be transported to the delta. Samples from the flood plains in Punjab show evidence for increased chemical weathering towards the top of the sections (6{\textendash}},
	issn = {0033-5894},
	doi = {10.1016/j.yqres.2012.01.008},
	url = {http://www.sciencedirect.com/science/article/pii/S0033589412000099},
	author = {Alizai, Anwar and Hillier, Stephen and Clift, Peter D. and Giosan, Liviu and Hurst, Andrew and VanLaningham, Sam and Macklin, Mark}
}
@article {227,
	title = {Pb isotopic variability in the modern-Pleistocene Indus River system measured by ion microprobe in detrital K-feldspar grains},
	journal = {Geochimica et Cosmochimica Acta},
	volume = {75},
	year = {2011},
	note = {id: 2171},
	pages = {4771-4795},
	abstract = {The western Himalaya, Karakoram and Tibet are known to be heterogeneous with regard to Pb isotope compositions in K-feldspars, which allows this system to be used as a sediment provenance tool. We used secondary ion mass spectrometry to measure the isotopic character of silt and sand-sized grains from the modern Sutlej and Chenab Rivers, together with Thar Desert sands, in order to constrain their origin. The rivers show a clear Himalayan provenance, contrasting with grains from the Indus Suture Zone, but with overlap to known Karakoram compositions. The desert dunes commonly show 207Pb/204Pb and 206Pb/204Pb values that are much higher than those seen in the rivers, most consistent with erosion from Nanga Parbat. This implies at least some origin from the trunk Indus, probably reworked by summer monsoon winds from the SW, a hypothesis supported by bulk Nd and U{\textendash}Pb zircon dating. Further data collected from Holocene and Pleistocene sands shows that filled and abandoned channels on the western edge of the Thar Desert were sourced from Himalayan rivers before and at 6{\textendash}8 ka, but that after that time the proportion of high isotopic ratio grains rose, indicating increased contribution from the Thar Desert dunes prior to \~{}4.5 ka when flow ceased entirely. This may be linked to climatic drying, northward expansion of the Thar Desert, or changes in drainage style including regional capture, channel abandonment, or active local Thar tributaries. Our data further show a Himalayan river channel east of the present Indus, close to the delta, in the Nara River valley during the middle Holocene. While this cannot be distinguished from the Indus it is not heavily contaminated by reworking from the desert. The Pb system shows some use as a provenance tool, but is not effective at demonstrating whether these Nara sediments represent a Ghaggar-Hakra stream independent from the Indus. Our study highlights an important role for eolian reworking of floodplain sediments in arid rivers such as the Indus.},
	issn = {0016-7037},
	doi = {10.1016/j.gca.2011.05.039},
	url = {http://www.sciencedirect.com/science/article/pii/S0016703711003164},
	author = {Alizai, Anwar and Clift, Peter D. and Giosan, Liviu and VanLaningham, Sam and Hinton, Richard and Tabrez, Ali R. and Danish, Muhammad}
}
