An integrated approach for reservoir characterisation in deep-water Krishna-Godavari basin, India: a case study

Abstract

The Miocene reservoirs in prolific Krishna-Godavari basin are mostly fluvial deposits and laminated or blocky in nature. The type of reservoir quality depends on associated geological environments. Due to several lateral variations in reservoir properties, a similar kind of workflow for reservoir characterisation does not work. Customised workflow needs to be applied in this area for estimation of petrophysical properties or rock physical analysis for reservoir quality prediction. As the major input of rock physical analysis is petrophysical properties, it is crucial to estimate these properties accurately. Meanwhile, it is also important to check the seismic sensitivity to change in fluid saturation in the reservoir characterisation process. The analysis assures the presence of reservoir and hydrocarbon contact in seismic sensitivity, which is essential for removing risk. Integrating the geological model with rock physical analysis for reservoir characterisation at the drilled well, the reservoir quality at undrilled prospects is predicted. In this study, the comprehensive study for reservoir characterisation of Miocene reservoirs consists of three different steps: calculation of petrophysical properties for mixed of thick and laminated sequence, rock physical analysis for identification of hydrocarbon reservoir and corresponding seismic sensitivity for change in saturation and finally the rock physics template for prediction of reservoir quality away from the drilled well. Results from the study have added significant value in de-risking the number of undrilled prospects in this area.

Controlling effect of source-reservoir assemblage on natural gas accumulation: A case study of the upper triassic xujiahe formation in the sichuan basin

“…The development scale of tight reservoirs in the Xujiahe Formation is mainly controlled by sedimentation, diagenesis and tectonic processes. Sedimentary facies, especially microfacies, are the basis for reservoir development (Yin et al, 2019;Mondal et al, 2021;Li., 2022). Distributary channels and estuary bars are favorable microfacies for reservoir development, while reservoirs in fluvial and lacustrine facies have poor physical properties.…”

Sedimentary Facies Types and Their Control of Reservoirs in the Lower Jurassic Lacustrine Facies Shale of the Lianggaoshan Formation, Northeastern Sichuan Basin, China

“…The mineral composition mainly includes clay minerals, and the content of feldspar and quartz is obviously smaller (average value of 51.1%). The content of felsic minerals in silty mudstone is relatively higher with an average value of 55.2%, and the color is lighter [45][46][47]. Felsic minerals are more obvious and the bitumen content is smaller in the fluorescent thin section (Figure 9e,f).…”

Contribution of Seismic Attributes in Delineating the Hydrocarbon Reservoir of Abu Madi Formation, West EL Manzala Area, the Eastern Part of Onshore Nile Delta, Egypt

“…Location and base map of the area under investigation are shown in Fig. (1), which is located between latitudes 31º 15', 31º 25' N and longitudes 31º 38', 31º 45' E. It is essential for effective reservoir management to have a comprehensive understanding of reservoir heterogeneity and rock type, but achieving this is hard due to the need for a variety of tools and methods for detection (Mondal et al, 2021). The present study tackled these issues via seismic interpretation using velocity gradient maps (average and interval), and time structure contour maps, as well as using seismic attributes to illustrate Abu Madi channel applying modern techniques of 2D seismic data reflection.…”