scholarly journals Sr and Nd isotopes in river sediments from the Ganga Basin: Sediment provenance and spatial variability in physical erosion

2008 ◽  
Vol 113 (F3) ◽  
Author(s):  
Sunil K. Singh ◽  
Santosh K. Rai ◽  
S. Krishnaswami
Keyword(s):  
Spatial Variability ◽  
River Sediments ◽  
Sediment Provenance ◽  
Nd Isotopes ◽  
Ganga Basin ◽  
Sr And Nd Isotopes ◽  
Physical Erosion

TACONIC WEATHERING AND ORDOVICIAN COOLING: TESTING THE LINK USING PAIRED SR AND ND ISOTOPES, ANTELOPE VALLEY, CENTRAL NV

2018 ◽  
Author(s):  
Christopher T. Conwell ◽  
◽  
Matthew R. Saltzman ◽  
Elizabeth M. Griffith
Keyword(s):  
Nd Isotopes ◽  
Sr And Nd Isotopes

Trace metal concentrations and OH defects in quartz from Amazon River sands & and perspectives for application to the marine record

2021 ◽  
Author(s):  
Dominik Jaeger ◽  
Roland Stalder ◽  
Cristiano Chiessi ◽  
André Sawakuchi ◽  
Michael Strasser
Keyword(s):  
Trace Metal ◽  
Drainage Basin ◽  
River Sediments ◽  
Sediment Provenance ◽  
Future Application ◽  
Amazon River ◽  
Analysis Tool ◽  
Metal Concentrations ◽  
Oh Defects ◽  
Quartz Grains

<p>Trace metal concentrations and associated hydrous lattice point defects (OH defects) in quartz can help reveal its host rock’s crystallization history and are easily quantified using electron microprobe and infrared spectroscopy, respectively. These chemical impurities are preserved throughout the sedimentary cycle and thus lend themselves as tracers for sediment provenance analyses, particularly in settings where “traditional” provenance tools, e.g., thermochronology and heavy mineral analysis, are difficult due to factors like low mineral fertility and aggressive tropical weathering.</p><p>In this study, we apply this provenance analysis tool to detrital, sand-sized quartz grains from the Amazon River and its major tributaries, draining the Andean orogen as well as the Guiana- and Central Brazil Shields. Trace metal and OH defect concentrations from individual catchments are spread out over wide and mutually overlapping ranges of values. This means that each individual quartz grain cannot be unequivocally attributed to one catchment. However, evaluation of a statistically sound number of grains reveals that Andean quartz is, on average, richer in the trace metal aluminum (and Al-related OH defects) than quartz derived from one of the shield sources.</p><p>We evaluate our findings in the context of previous provenance studies on Amazon River sediments and discuss a potential future application of analyzing trace metals and OH defects in quartz in the offshore sediment record. Any past, major rearrangements in the Amazon watershed affecting the ratio of Andean vs. Shield-derived quartz grains should be detectable and our approach may therefore contribute to the reconstruction of Amazon drainage basin evolution.</p>

Mantle diversity beneath the Colombian Andes, Northern Volcanic Zone: Constraints from Sr and Nd isotopes

Lithos ◽  
2005 ◽  
Vol 82 (3-4) ◽  
pp. 471-484 ◽  
Author(s):  
A. Rodriguez-Vargas ◽  
E. Koester ◽  
G. Mallmann ◽  
R.V. Conceição ◽  
K. Kawashita ◽  
...  
Keyword(s):  
Volcanic Zone ◽  
Nd Isotopes ◽  
Sr And Nd Isotopes ◽  
Colombian Andes ◽  
Northern Volcanic Zone

Late Quaternary climatic control on erosion and weathering in the eastern Tibetan Plateau and the Mekong Basin

2005 ◽  
Vol 63 (3) ◽  
pp. 316-328 ◽  
Author(s):  
Zhifei Liu ◽  
Christophe Colin ◽  
Alain Trentesaux ◽  
Giuseppe Siani ◽  
Norbert Frank ◽  
...  
Keyword(s):  
Grain Size ◽  
Tibetan Plateau ◽  
Chemical Weathering ◽  
River Sediments ◽  
River Estuary ◽  
Mekong River ◽  
Sediment Discharge ◽  
Eastern Tibetan Plateau ◽  
Mekong Basin ◽  
Physical Erosion

High-resolution siliciclastic grain size and bulk mineralogy combined with clay mineralogy, rubidium, strontium, and neodymium isotopes of Core MD01-2393 collected off the Mekong River estuary in the southwestern South China Sea reveals a monsoon-controlled chemical weathering and physical erosion history during the last 190,000 yr in the eastern Tibetan Plateau and the Mekong Basin. The ranges of isotopic composition are limited throughout sedimentary records:87Sr/86Sr = 0.7206–0.7240 andεNd(0) = −11.1 to −12.1. These values match well to those of Mekong River sediments and they are considered to reflect this source region. Smectites/(illite + chlorite) and smectites/kaolinite ratios are used as indices of chemical weathering rates, whereas the bulk kaolinite/quartz ratio is used as an index of physical erosion rates in the eastern Tibetan Plateau and the Mekong Basin. Furthermore, the 2.5–6.5 μm/15–55 μm siliciclastic grain size population ratio represents the intensity of sediment discharge of the Mekong River and in turn, the East Asian summer monsoon intensity. Strengthened chemical weathering corresponds to increased sediment discharge and weakened physical erosion during interglacial periods. In contrast, weakened chemical weathering associated with reduced sediment discharge and intensified physical erosion during glacial periods. Such strong glacial–interglacial correlations between chemical weathering/erosion and sediment discharge imply the monsoon-controlled weathering and erosion.

Spatial variability of climate change impacts on yield of rice and wheat in the Indian Ganga Basin

2013 ◽  
Vol 468-469 ◽  
pp. S132-S138 ◽  
Author(s):  
Ashok Mishra ◽  
R. Singh ◽  
N.S. Raghuwanshi ◽  
C. Chatterjee ◽  
Jochen Froebrich
Keyword(s):  
Climate Change ◽  
Spatial Variability ◽  
Climate Change Impacts ◽  
Ganga Basin
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