The coastal dunes located near the Ashirmata region, south of Mandvi beach lies near the straight coast have been stud-ied by making use of sedimentological information and Ground Penetrating Radar (GPR) data. Sedimen...The coastal dunes located near the Ashirmata region, south of Mandvi beach lies near the straight coast have been stud-ied by making use of sedimentological information and Ground Penetrating Radar (GPR) data. Sedimentological analy-sis reveals the NNW-SSE trending longitudinal dunes consists of well sorted fine sands with unimodal distribution pos-sibly formed by constant wind gust and also the point out to the origin of sediments from single source;mostly the sediments derived from Indus delta transported to beach by long shore drift and tidal waves, carried inland by local on-shore winds. The radargram confirms, the homogenous sand layers with paleosols at shallow depth slip faces are proba-bly formed due to extreme storm activity of Recent.展开更多
The textural and mineralogical characteristics of subsurface sediments along with Ground Penetrating Radar (GPR) data collected along the Western margin of India were used to understand the depositional environments a...The textural and mineralogical characteristics of subsurface sediments along with Ground Penetrating Radar (GPR) data collected along the Western margin of India were used to understand the depositional environments and the provenance of sediments. Textural attributes such as mean, standard deviation, skewness and Kurtosis show fluctuations due to fluvio-marine interaction and it is well understood that the bottom sediments are enriched with muddy sand, which may be deposited by mean of tidal invasion. The abundance of very coarse silt to very fine sand indicates the prevalence of low energy environment. The Linear Discriminate Function analysis indicates the fluvio marine deposition of sediments under low energy condition. GPR data upto a depth of 5 m shows the stratigraphic sequences of very fine sands and coarse silt. Optically Stimulated Luminescence (OSL) dating of sediments implies that the tidal sediments had deposited between ~30 ± 1 and ~90 ± 4 years before Present. XRD studies results the dominance of K-feldspar and deficiency of clay minerals, indicating that most of the sediments are derived from hinterland. Studies indicate that the Provenance of sediments in the Mandvi area is not related to Indus delta even though a considerable part of Gulf sediments are deposited by the Indus River.展开更多
文摘The coastal dunes located near the Ashirmata region, south of Mandvi beach lies near the straight coast have been stud-ied by making use of sedimentological information and Ground Penetrating Radar (GPR) data. Sedimentological analy-sis reveals the NNW-SSE trending longitudinal dunes consists of well sorted fine sands with unimodal distribution pos-sibly formed by constant wind gust and also the point out to the origin of sediments from single source;mostly the sediments derived from Indus delta transported to beach by long shore drift and tidal waves, carried inland by local on-shore winds. The radargram confirms, the homogenous sand layers with paleosols at shallow depth slip faces are proba-bly formed due to extreme storm activity of Recent.
文摘The textural and mineralogical characteristics of subsurface sediments along with Ground Penetrating Radar (GPR) data collected along the Western margin of India were used to understand the depositional environments and the provenance of sediments. Textural attributes such as mean, standard deviation, skewness and Kurtosis show fluctuations due to fluvio-marine interaction and it is well understood that the bottom sediments are enriched with muddy sand, which may be deposited by mean of tidal invasion. The abundance of very coarse silt to very fine sand indicates the prevalence of low energy environment. The Linear Discriminate Function analysis indicates the fluvio marine deposition of sediments under low energy condition. GPR data upto a depth of 5 m shows the stratigraphic sequences of very fine sands and coarse silt. Optically Stimulated Luminescence (OSL) dating of sediments implies that the tidal sediments had deposited between ~30 ± 1 and ~90 ± 4 years before Present. XRD studies results the dominance of K-feldspar and deficiency of clay minerals, indicating that most of the sediments are derived from hinterland. Studies indicate that the Provenance of sediments in the Mandvi area is not related to Indus delta even though a considerable part of Gulf sediments are deposited by the Indus River.
