Mineralogy and Major Element Geochemistry of the Oligocene Barail Group Sandstones from the Sylhet Trough, Bengal Basin: Provenance and Tectonic Implications

The origin of Oligocene sediments in the Bengal Basin and associated tectonic setting remain poorly understood. This study investigates the framework mineralogy and major element geochemistry of the Barail Group sandstones from the Sylhet Trough within the Bengal Basin to clarify the provenance and...

Full description

Saved in:
Bibliographic Details
Published in:Minerals (Basel) 2024-10, Vol.14 (10), p.985
Main Authors: Mohinta, Sunjuckta, Sayem, Abu Sadat Md, Rahman, M. Julleh Jalalur, Alam, Md Sha, Abdullah, Rashed
Format: Article
Language:English
Subjects:
Analysis
Basins (Geology)
Chemical weathering
Cratons
Detritus
Geochemistry
Geology
Humid climates
Lithium compounds
Mineral assemblages
Mineralogy
Minerals
Modal analysis
Oligocene
Passive margins
Provenance
Rutile
Sandstone
Sediment
Sediments
Sediments (Geology)
Soil erosion
Tectonics
Tectonics (Geology)
Tourmaline
Zircon
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The origin of Oligocene sediments in the Bengal Basin and associated tectonic setting remain poorly understood. This study investigates the framework mineralogy and major element geochemistry of the Barail Group sandstones from the Sylhet Trough within the Bengal Basin to clarify the provenance and tectonic history of the Oligocene. Modal analysis (Q83F7L10) and geochemical data support a classification of sublitharenite to subarkose, some with Fe enrichment. The heavy mineral assemblage is dominated by opaque minerals, followed by ultrastable minerals with zircon > tourmaline > rutile. The sub-angular to sub-rounded sand grains with a compositionally moderate mature nature suggest that the sediments were deposited close to the source area. The mineralogical and geochemical provenance discrimination diagram suggests contributions from felsic igneous, sedimentary/metasedimentary, and low-grade metamorphic sources, with detritus derived from the Indian craton and proto-Himalaya region. Data suggest moderate to intense chemical weathering, indicative of low relief and a sub-humid to humid climate in the source area. The tectonic analyses indicate that the Bengal Basin transitioned from a predominantly passive margin to an active tectonic margin setting during the Oligocene.
ISSN:2075-163X
2075-163X
DOI:10.3390/min14100985