TITLE:
Granulometric and Facies Analysis of Sandstone Reservoir of the Y-Field in the Tano Basin, Ghana
AUTHORS:
Asare Asante-Annor, Ebenezer Ansah, Priscilla Efua Baiden, Clement Nuamah, Mark Prempeh
KEYWORDS:
Granulometric Analysis, Sediment Classification, Grain Size, Facies Analysis
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.14 No.7,
July
24,
2026
ABSTRACT: Grain size analysis is an essential sedimentological tool for determining hydrodynamic conditions, mode of transport and deposition of detrital sediments. In this study, detailed grain size analysis was conducted using fifty-six sieve analysis samples acquired from a total of three well core data (WX, WY and WZ) in order to determine the depositional environment of the Y-Field in the Jubilee Field, a hydrocarbon reservoir, supported by facies analysis. Depositional environments, hydrodynamic conditions and mode of sediment transport were determined using bivariate plots and linear discriminate function (LDF) analysis. The results reveal that the unit consists of medium to silt sands with majority being poorly sorted. The sediments have a unimodal distribution of
2ϕ
and
1ϕ
, while few beds have a bimodal of
3ϕ
,
4ϕ
,
5ϕ
,
6ϕ
,
7ϕ
and
8ϕ
. The unit has near symmetrical to very fine skewed but mostly platykurtic to very leptokurtic sediments. Bivariate plots of the statistical measures show that the depositional environments were impacted mostly by river conditions. Additionally, the cumulative frequency curves show that the majority of the sediments were transported via saltation while fine grains were transported by suspension and a few indications of the traction process. The sediment classification ternary diagram reveals that 44% of the samples are silty sand, 22% sandy silt and 6% sand per the fine plot. For the coarse plot, most of the samples (22%) are slightly gravelly sand with one sample (6%) being gravelly muddy sand. The Shepard 1954 classification revealed for the coarse plot as sand, silt and clay which is about 28%. Most of the samples (50%) grouped in the sand region and few others (22%) in the silty sand and sandy silt regions (22%) in the fine plot. The results of the LDF analysis are mainly indicative of shallow marine, beach, turbidity current and fluvial environments.