Textural and Sediment Component Dataset of Unconsolidated Sediments from Agatti and Kavaratti Lagoon
Description
Lakshadweep Archipelago, located in the Northern Indian Ocean, is a group of 36 islands and five submerged reefs, off the coast of the Indian Peninsula. This dataset includes sedimentological (grain size and sediment component) and depth, along with the location of samples (unconsolidated sediments from lagoon) compiled in Excel file format. Field investigations were conducted for Agatti and Kavaratti in March and October 2023. Grid sampling with an approx. spacing of 500m was conducted across the lagoons. Forty-two samples were collected from Agatti lagoon (area- 17.5 km2) and twenty-four samples from Kavaratti lagoon (area – 5 km2). Wet sieving of the subsamples was conducted to categorize them into the following grain size fractions - 4 – 2mm, 2 – 0.5mm, 0.5 – 0.25mm, 0.25 – 0.125mm, 0.125 – 0.063mm, <0.063mm. The samples were then categorized texturally, based on the Dunham classification. The thin sections from sample locations (n = 15, Agatti and n = 9, Kavaratti) for each grain size fraction (2 – 0.5mm, 0.5 – 0.25mm, 0.25 – 0.125mm) were analyzed with a Leica DM750 polarizing microscope. Point counting of each sediment component was carried out using JMicroVision software. The major sediment components identified include coral clasts, molluscs, algae, Halimeda and forams. Halimeda was identified separately as a sediment component due to its significance as a major sediment producer. This dataset consists of four Excel files (1)Depth, (2) Dunham texture, (3 and 4) Sediment component analysis for Agatti and Kavaratti. The location of all the samples collected is also attached to the dataset. These datasets will aid in understanding the mechanisms governing the sediment dynamics in atoll islands.