Chemical weathering in Malay Peninsula and North Borneo: Clay mineralogy and element geochemistry of river surface sediments

We performed mineralogical and geochemical analyses of core samples from the Lenghuqi area in the northern marginal tectonic belt of the Qaidam Basin. The clay mineralogy of the Xiaganchaigou Formation sandstone is dominated by I + I/S + C types and characterized by high illite, a higher mixed-layer illite/smectite and chlorite, lesser smectite, and an absence of kaolinite. The clay minerals reflect that the Oligocene sedimentary basin formed in an arid-semi-arid climate with weak leaching and chemical weathering, and that diagenesis occurred in a K+- and Mg2+-rich alkaline environment. Measured major oxide concentrations show clear correlations. The lower Xiaganchaigou Formation is representative of a dry and cold freshwater sedimentary environment, whereas the upper Xiaganchaigou Formation is warmer and more humid. Trace element and rare earth element variations indicate that the paleoclimate conditions of the lower Xiaganchaigou Formation sedimentary period were relatively cold and dry, while the upper Xiaganchaigou Formation formed under warmer and more humid climate conditions. These findings reflect a global climate of a cold and dry period from the late Eocene to early Oligocene, and a short warming period in the late Oligocene.

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Chemical weathering in central Vietnam from clay mineralogy and major-element geochemistry of sedimentary rocks and river sediments

Heliyon ◽

10.1016/j.heliyon.2018.e00710 ◽

2018 ◽

Vol 4 (7) ◽

pp. e00710 ◽

Cited By ~ 2

Author(s):

Pham Nhu Sang ◽

Zhifei Liu ◽

Yulong Zhao ◽

Xixi Zhao ◽

Phan Dong Pha ◽

...

Keyword(s):

Chemical Weathering ◽

Major Element ◽

River Sediments ◽

Sedimentary Rocks ◽

Clay Mineralogy ◽

Element Geochemistry ◽

Central Vietnam

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Effect of mining-related activities on the sediment-trace element geochemistry of Lake Coeur d'Alene, Idaho, USA; Part 1, surface sediments

Open-File Report ◽

10.3133/ofr92109 ◽

1992 ◽

Cited By ~ 3

Author(s):

Arthur J. Horowitz ◽

Kent A. Elrick ◽

Robert B. Cook

Keyword(s):

Trace Element ◽

Surface Sediments ◽

Trace Element Geochemistry ◽

Element Geochemistry ◽

Coeur D'alene

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Clay Mineralogy and Geochemistry of the Pockmarked Surface Sediments from the Southwestern Xisha Uplift, South China Sea: Implications for Weathering and Provenance

Geosciences ◽

10.3390/geosciences11010008 ◽

2020 ◽

Vol 11 (1) ◽

pp. 8

Author(s):

Mei Zhang ◽

Hongfeng Lu ◽

Qing Chen ◽

Gayan Bandara ◽

Hui Zhang ◽

...

Keyword(s):

South China Sea ◽

Clay Minerals ◽

South China ◽

Surface Sediments ◽

Northern South China Sea ◽

Clay Mineralogy ◽

Xrd Analysis ◽

Average Weight ◽

X Ray ◽

China Sea

In the northern South China Sea, pockmarks are widely distributed on the seabed offshore on the southwestern Xisha Uplift. The mineralogy and geochemistry of the clay minerals and surface sediments from the pockmark field were identified using X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) analysis to trace the provenance, weathering, and sediment transportation system in the area. The clay minerals are primarily comprised of illite, smectite, kaolinite, and chlorite, showing a distribution of average weight percentages of 35%, 35%, 18%, and 13%, respectively. Based on the surrounding fluvial drainage basins and various transport mechanisms (current or monsoon), illite and chlorite primarily originate from rivers in Taiwan and the Mekong and Red Rivers. Kaolinite primarily originates from the Pearl River, and smectite derived from the Luzon arc system is primarily transported by surface currents with significant influence from the Kuroshio intrusion.

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Sediment Sources and Dispersion on the Western Sunda Shelf, Malay Peninsula, Southern South China Sea

Water ◽

10.3390/w13202823 ◽

2021 ◽

Vol 13 (20) ◽

pp. 2823

Author(s):

Yanguang Liu ◽

Chuanshun Li ◽

Ramlan Bin Omar ◽

Xuefa Shi ◽

Hui Zhang ◽

...

Keyword(s):

Grain Size ◽

Surface Sediment ◽

Surface Sediments ◽

The Other ◽

Coarse Grained ◽

Malay Peninsula ◽

Sediment Sources ◽

Southern South China Sea ◽

Sunda Shelf ◽

Sediment Samples

Thirty-nine surface sediment samples collected from the western Sunda Shelf off the Malay Peninsula (WSSMP) in the southern South China Sea (SCS) were analysed for grain size, major and trace elemental compositions, and light/heavy mineral contents to trace the sediment sources and their transport mechanisms in the study area. In the WSSMP, the surface sediments are relatively poorly sorted but transportable. A principal component analysis of 37 elements and grain size fractions indicates that the surface sediments can be grouped into four major assemblages in the study area. Integrating with the light/heavy minerals data in the 63–125 μm fractions of the surface sediment samples, to better trace the sediment sources of the coarse-grained components in the marine environment, the study area can be further divided into four sediment provinces. Province I is located in the northwestern part of the study area. The concentrations of TiO2, Na2O, garnet, siderite, and glauconite in Province I were higher than in the other provinces. The main sediment source for this province originated from the Kelantan River and the Gulf of Thailand transported by the northeastern monsoon current. Province II is located offshore of the Pahang and Endau Rivers. The percentages of TiO2, rare earth elements, Al2O3, quartz, plagioclase, hypersthene, and magnetite in the surface sediments were typically higher in this province than in the other provinces. The Pahang and Endau rivers provide most of the sediments to this province, which are transported by southward coastal currents. Province III is located in the northeastern and eastern parts of the study area, where the coarse-grained sediment fraction had relatively high hornblende and biotite contents. Sediments in this province are mostly transported from the Mekong River during the northeastern monsoon. The other parts of the study area belong to Province IV, where the surface sediment elemental and mineral concentrations were mostly between those of the other three provinces. Therefore, we suggest that Province IV has a mixed source due to inputs from the surrounding rivers.

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Middle Triassic to Late Jurassic climate change on the northern margin of the South China Plate: Insights from chemical weathering indices and clay mineralogy

Palaeogeography Palaeoclimatology Palaeoecology ◽

10.1016/j.palaeo.2021.110744 ◽

2021 ◽

pp. 110744

Author(s):

Xianduo Dai ◽

Yuansheng Du ◽

Martin Ziegler ◽

Chaowen Wang ◽

Qianli Ma ◽

...

Keyword(s):

Climate Change ◽

South China ◽

Late Jurassic ◽

Chemical Weathering ◽

Middle Triassic ◽

Clay Mineralogy ◽

The South ◽

Northern Margin ◽

Weathering Indices

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Chemical weathering response to extreme global warming during Paleocene-Eocene Hyperthermals, Southern Pyrenees, Spain

10.5194/egusphere-egu21-12452 ◽

2021 ◽

Author(s):

Rocio Jaimes-Gutierrez ◽

Thierry Adatte ◽

Emmanuelle Puceat ◽

Jean Braun ◽

Sebastien Castelltort

Keyword(s):

Climatic Change ◽

Chemical Weathering ◽

Numerical Models ◽

Clay Fraction ◽

Clay Mineralogy ◽

Foreland Basin ◽

Isotopic Analysis ◽

Feedback Mechanism ◽

Horizon 2020 ◽

Sediment Routing

The Paleocene and early Eocene were periods yielding multiple hyperthermal events. The most pronounced of them was the Paleocene-Eocene Thermal Maximum (PETM), which was characterized by an abrupt increase in global temperature (5&#8211;8 &#176;C) over a short time (20 ka). A negative carbon isotope excursion marks the onset of the PETM, which resulted in the fast injection of CO2 into the ocean-atmosphere system, triggering global climatic changes. Geochemical, mineralogical, and sedimentological markers record the resulting increase in continental weathering. This is important, as enhanced chemical erosion influences both the CO2 concentration in the atmosphere and ocean acidity, generating a feedback mechanism. Hence, constraining the rates and intensity of weathering response can further clarify the causes for the PETM and Eocene hyperthermals. This study focuses on the well-preserved Pyrenean foreland basin and intends to assess the continental chemical weathering response of the sediment routing system during the PETM. Clay mineralogy is a climate-sensitive proxy, which records changes in continental erosion. Therefore, clay mineral proportions will be analyzed using X-ray diffraction and major element chemistry on clay-rich samples from the entire source-to-sink system (continental to deep marine deposits). Kaolinite and smectite will be separated from the detrital clay fraction and further subjected to &#948;18O and &#948;D isotopic analysis for paleoclimatic reconstruction. The combined Lu-Hf and Sm-Nd isotope systems in the clay fraction of the sediments will be used to track the evolution of chemical weathering intensity. The outcome of this project will serve to validate numerical models to understand erosion as a function of rapid climatic change. This topic is of keen interest, as the PETM and its sedimentological signal work as a natural analog for anthropogenically-induced climatic change. The project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No 860383.

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