Texture and mineralogy of sediments from the Ganges-Brahmaputra-Meghna river system in the Bengal Basin, Bangladesh and their environmental implications

Datta, Dilip Kumar; Subramanian, V.

doi:10.1007/s002540050145

Cited by 122 publications

(55 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, in order to understand the nature of heavy metals in sediments, the geochemical index (I geo ) was made. Observations made for the I geo of Cd from the earlier studies by Datta and Subramanian (1997) in the Bengal basin rivers show a marginal enrichment factor, while other heavy metals have a negative I geo value. This suggests that the influence of anthropogenic contaminants in the deposited sediments is minimal.…”

Section: Resultsmentioning

confidence: 99%

“…In G-B system illite is the most abundant clay mineral (Table 1(b)) followed by kaolinite, smectite and chlorite (Sarin et al, 1989). Illite and kaolinite constitute 80% of the total clay mineral distribution in the rivers of the Bengal basin (Meghna, Padma and Jamuna) and has an almost negligible montmorillonite content (Datta and Subramanian, 1997). The richness of illite is related to the dominance of its precursor, the muscovite type mica in the source rock (Segall and Kuehl, 1992) and due to the neotectonic activity of the basin (Irion, 1991;Pant and Sharma, 1993).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Distribution of rare earth elements and heavy metals in the surficial sediments of the Himalayan river system.

et al. 2000

Self Cite

View full text Add to dashboard Cite

Rare earth elements (REEs) are considered as useful tracers of various surface geological processes in the river system. REEs and heavy metals (V, Pb, Cr, Co, Ag, Zn, Cd, Ni) were analyzed from the suspended sediments of Ganges and surficial sediments of Yamuna, Brahmaputra, Jamuna, Padma and Meghna, using VG Thermal Ionization Mass Spectrometer. Physical weathering process seems to be a major controlling factor for the distribution of REE and trace metals in the sediments of the Himalayan rivers. Weathering of the surface crustal area in the drainage basin shows significant variations due to changes in lithology and influence of tributaries. The distribution of REE shows an almost uniform pattern due to factors such as river transportation processes and high level of terrigenous mixing in the bed sediments. The results show that finer grain size and high content of clay mineral (illite) in these sediments are possible traps for the accumulation of metals. Anthropogenic activities seem to have very little influence in controlling the elemental distribution in the Himalayan rivers.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Distribution of rare earth elements and heavy metals in the surficial sediments of the Himalayan river system.

et al. 2000

Self Cite

View full text Add to dashboard Cite

show abstract

“…Ancillary arsenic release may also occur during weathering of feldspars, biotite, and hornblende. These minerals are common in Bangladesh aquifers (6,31,38), and they have been shown to be potential sites of microbial weathering (5,36,37,40).…”

mentioning

confidence: 99%

“…Apatite, Ca 5 (PO 4 ) 3 (F,Cl,OH), is an abundant source of phosphate and is present in the aquifers and rivers of Bangladesh (6,22). Dissolution of 13 purified apatite samples from the Himalayas resulted in an average arsenic concentration of 210 mg/kg (all values are 1, 3, 10, 11, 15, 24, 51, 78, 110, 200, 220, 250, and 1,800 mg/kg).…”

mentioning

confidence: 99%

Microbial Mineral Weathering for Nutrient Acquisition Releases Arsenic

Mailloux

Alexandrova

Keimowitz

et al. 2009

Appl Environ Microbiol

View full text Add to dashboard Cite

Tens of millions of people in Southeast Asia drink groundwater contaminated with naturally occurring arsenic. How arsenic is released from the sediment into the water remains poorly understood. Here, we show in laboratory experiments that phosphate-limited cells of Burkholderia fungorum mobilize ancillary arsenic from apatite. We hypothesize that arsenic mobilization is a by-product of mineral weathering for nutrient acquisition. The released arsenic does not undergo a redox transformation but appears to be solubilized from the apatite mineral lattice during weathering. Analysis of apatite from the source area in the Himalayan basin indicates the presence of elevated levels of arsenic, with an average concentration of 210 mg/kg. The rate of arsenic release is independent of the initial dissolved arsenic concentration and occurs at phosphate levels observed in Bangladesh aquifers. We also demonstrate the presence of the microbial phenotype that releases arsenic from apatite in Bangladesh aquifer sediments and groundwater. These results suggest that microbial mineral weathering for nutrient acquisition could be an important mechanism for arsenic mobilization.

show abstract

“…The majority of sediment delivered to tributaries of the GBM is fine sand, with a relatively low silt fraction from Precambrian metasedimentary rocks (Datta and Subramanian, 1997;Mukherjee et al, 2009). The sediments in the channels are thus primarily unconsolidated, with the high sediment yields leading to a dynamic braiding/anabranching pattern in the majority of channels within the GBM basin.…”

Section: A New Classification Of Planform Confluence Behaviourmentioning

confidence: 99%

The Planform Mobility of River Channel Confluences: Insights from Analysis of Remotely Sensed Imagery

Dixon¹,

Smith²,

Best³

et al. 2017

Preprint

View full text Add to dashboard Cite

A B S T R A C TRiver channel confluences are widely acknowledged as important geomorphological nodes that control the downstream routing of water and sediment, and which are locations for the preservation of thick fluvial deposits overlying a basal scour. Despite their importance, there has been little study of the stratigraphic characteristics of river junctions, or the role of confluence morphodynamics in influencing stratigraphic character and preservation potential. As a result, although it is known that confluences can migrate through time, models of confluence geomorphology and sedimentology are usually presented from the perspective that the confluence remains at a fixed location. This is problematic for a number of reasons, not least of which is the continuing debate over whether it is possible to discriminate between scour that has been generated by autocyclic processes (such as confluence scour) and that driven by allocyclic controls (such as sea-level change). This paper investigates the spatial mobility of river confluences by using the 40-year record of Landsat Imagery to elucidate the styles, rates of change and areal extent over which large river confluence scours may migrate. On the basis of these observations, a new classification of the types of confluence scour is proposed and applied to the Amazon and Ganges-Brahmaputra-Meghna (GBM) basins. This analysis demonstrates that the drivers of confluence mobility are broadly the same as those that drive channel change more generally. Thus in the GBM basin, a high sediment supply, large variability in monsoonal driven discharge and easily erodible bank materials result in a catchment where over 80% of large confluences are mobile over this 40-year window; conversely this figure is < 40% for the Amazon basin. These results highlight that: i) the potential areal extent of confluence scours is much greater than previously assumed, with the location of some confluences on the Jamuna (Brahmaputra) River migrating over a distance of 20 times the tributary channel width; ii) extensive migration in the confluence location is more common than currently assumed, and iii) confluence mobility is often tied to the lithological and hydrological characteristics of the drainage basins that determine sediment yield.

show abstract

Texture and mineralogy of sediments from the Ganges-Brahmaputra-Meghna river system in the Bengal Basin, Bangladesh and their environmental implications

Cited by 122 publications

References 34 publications

Distribution of rare earth elements and heavy metals in the surficial sediments of the Himalayan river system.

Distribution of rare earth elements and heavy metals in the surficial sediments of the Himalayan river system.

Microbial Mineral Weathering for Nutrient Acquisition Releases Arsenic

The Planform Mobility of River Channel Confluences: Insights from Analysis of Remotely Sensed Imagery

Contact Info

Product

Resources

About