Prediction of Pore Fluid and Lithology Using Incompressibility and Rigidity, Offshore Niger Delta, Nigeria

Year 2020, Volume: 2 Issue: 3, 109 - 120, 15.10.2020

Ojo Odunayo Agbasi Okechukwu Namdie Inyang Etuk Sunday Robert Ubong

Abstract

Pore fluid and lithology content was determined using the calculated velocity ratio and Poisson’s ratio. From the analysis of velocity ratio and Poisson’s ratio, the gas sand, oil sand, and brine sand were mapped out. The gas sand predicted from the rock physics analysis using lambda-mho and mu-rho was confirmed by the analysis of velocity ratio and Poisson’s ratio. The analysis of velocity ratio and Poisson’s ratio was used to further describe the wet sand predicted by the rock physics analysis of lambda-mho and mu-rho. The wet sand from the rock physics analysis of lambda-mho and mu-rho was predicted to comprise of oil sand and brine sand. The value of lambda-mho is between 21.74 to 25.67, for mu-rho is between 16.34 to 23.21 for Poisson’s ratio is between 0.25 to 0.29 and for Vp/Vs ratio is between 1.74 to 1.83, these confirm the presence of oil sand in all the seven (7) reservoirs studied in two (2) wells, all the reservoirs fall between the Agbada region (10212.50-11741.00 ft) and have a very good net pay zone ranging from 41.50 ft to 193.00 ft in the Niger Delta region, Nigeria.

Keywords

Mu-Rho, Lambda Rho, Density, Velocities, Lame Parameters

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