Physio-Chemical and Mineralogical Characteristics of Gas Hydrate-Bearing Sediments of the Kerala-Konkan, Krishna-Godavari, and Mahanadi Basins

Abstract

The characteristics of the hydrate-bearing sediments affect the formation and dissociation of gas hydrate in sediments. The mineral composition, their dispersion, and chemical composition of hydrate-bearing sediment samples plays a dominant role in the hydrate stability condition and its economic development. In this paper, the physical properties of hydrate-bearing sediment of India are compared with each other. The sediment samples are taken from the Krishan-Godavari basin (Depth—127.5 and 203.2 mbsf), Mahanadi basin (Depth—217.4 mbsf), and Kerala-Konkan basin (Depth—217.4 mbsf). The saturation of the gas hydrate observed at these sites is between 3 and 50%. Particle size is an important parameter of the sediments because it provides information on the transportation and deposition of sediment and the deposition history. In the present study, we investigated the mineralogy of hydrate-bearing sediments by chemical analysis and X-ray Diffraction. XRD, FTIR, and Raman Spectroscopy distinguished the mineralogical behavior of sediments. Quartz is the main mineral (66.8% approx.) observed in the gas hydrate-bearing sediments. The specific surface area was higher for the sediment sample from the Mahanadi basin, representing the sediments’ dissipation degree. This characterization will give important information for the possible recovery of gas from Indian hydrate reservoirs by controlling the behavior of host sediment. SEM analysis shows the morphology of the sediments, which can affect the mechanical properties of the hydrate-bearing sediments. These properties can become the main parameters to consider for the design of suitable and economic dissociation techniques for gas hydrates formed in sediments.

Microbial communities associated with thermogenic gas hydrate-bearing marine sediments in Qiongdongnan Basin, South China Sea

“…Aerophobetes have been detected in the gas hydrate-bearing zone of sediment cores in relative higher abundance compared to hydrate-free sediments in the South China Sea earlier ( Cui et al, 2019 , 2020 ) and in some cold seep environments ( Wang et al, 2016 ; Huang et al, 2019 ). It has been discovered that gas hydrate dynamics could be affected by properties of gas hydrate-bearing sediments, such as particle size, sediment components and porosity ( Lu et al, 2011 ; Kumari et al, 2021 ). At depths of 62 and 64 mbsf, elements Fe, Mn, Ca, Al, and K in sediments showed sharp decreases, while Si and Ti increased.…”

Acoustic Wave Propagation in a Borehole with a Gas Hydrate-Bearing Sediment

“…The Carcione-Leclaire theory predicts three compressional and two shear waves in a three-phase porous medium: the first kind of compressional (P1), shear (S1) waves, the second kind of compressional (P2), shear (S2) waves, and the third kind of compressional (P3) wave. Up to date, much work has been done to study the characteristics of gas hydrate-bearing sediments [12][13][14][15][16][17][18]. However, there is almost no research on the wave propagation in a borehole surrounded by a hydrate formation, therefore, how to better use the acoustic well logging information to evaluate the parameters of hydrate formation lacks sufficient theoretical guidance.…”

Intensification of Gas Hydrate Formation Processes by Renewal of Interfacial Area between Phases

“…As for the second issue, the hydrate formation rate, in our opinion, it is the hydrate itself that causes a significant decrease in the intensity of diffusion flows in the reaction zone. Diffusion processes have also been studied by many authors [24][25][26][27], however, in their works the transfer process itself was considered with no consequent conclusions regarding the sufficiently high intensity of mass transfer. Currently, in the literature references, one may encounter descriptions of many devices for GH production [28][29][30][31][32][33][34][35], where the biggest attention is drawn to methods used to increase the gas and liquid contact area, either by dispersing water in a gas or by the formation of a bubble gas flow in water.…”