Formation evaluation of the petrophysical properties of wells in e - field onshore Niger Delta, Nigeria

Abstract

Integrated wireline logs and lithostratigraphic techniques were employed to determine the lithological and petrophysical properties of wells A and B in E- field, onshore Niger Delta. The Reservoirs in both wells were analyzed using a minimum thickness or depth of penetration of 5.0m. For the two wells, Gas Water Contact (GWC), Gas Oil Contact (GOC), and Oil Water Contact (OWC) were found to be present at varying formation depths. GWC, GOC, and OWC at depth of 2967.50m, 3348m and 2286m respectively for well A and a GOC at depth 1715m for well B. The correlation of both wells reveals a gas reservoir, water reservoir, and a non-resistive, but highly
conductive zone at 2450m, 2500m, and 2150m depth respectively. The formation porosity (∅?), total porosity (∅?), effective porosity (∅?) and resistivity values of well A ranges from (27.27 - 39.59) %, (1.3x10 ^–1 - 37.82) %, ( 1.638x10^{– 4} – 81. 38)%, (2.05 - 150)Ωm respectively. Conversely, well B measured (27.27 - 36.50) %, (2.25x10^–2 - 93.0) %, (9.75x10^{– 4} - 32.79) % and (2 – 200) Ωm respectively. Hydrocarbon saturation (SHC) and Bulk volume of Hydrocarbon (BVH) for well A ranges from (73.27-95.10)% and (24.24 - 34. 58)% while that of well B ranges from (77.10 - 97. 90)% and (23.36 - 35.53)% for SHC and BVH respectively. The average ∅? and ∅? of 56.2% and 42.6% reveal excellent porosities in well A and reservoirs 2,3,4a and 11 in well B with average ∅?and ∅? of 37.82% and 30.6% also show an excellent porosities. The result from the Petrophysical indices indicates pay zones at reservoirs 10a, 10b and 11 in well A and
reservoir 11 in well B which are predominantly gas reserves.

Keywords: Reservoirs, Onshore, Oil and Gas, Petrophysical properties, Niger Delta and Lithology