Calculating Gas in Place Using Material Balance

In the previous sections, the initial gas in place was calculated on a unit basis of 1 ac-ft of bulk productive rock, given information on the porosity and connate water. To calculate the initial gas in place on any particular portion of a reservoir, it is necessary to know, in addition, the bulk volume of… Continue reading Calculating Gas in Place Using Material Balance

Calculating Unit Recovery from Gas Reservoirs under Water Drive

Under initial conditions, one unit (1 ac-ft) of bulk reservoir rock contains Connate water: 43,560 × φ × Swi ft3 Reservoir gas volume: 43,560 × φ × (1 – Swi) ft3 Surface units of gas: 43,560 × φ × (1 – Swi) ÷ Bgi SCF In many reservoirs under water drive, the pressure suffers an initial decline, after which water enters the reservoir at a… Continue reading Calculating Unit Recovery from Gas Reservoirs under Water Drive

Calculating Unit Recovery from Volumetric Gas Reservoirs

In many gas reservoirs, particularly during the development period, the bulk volume is not known. In this case, it is better to place the reservoir calculations on a unit basis, usually 1 ac-ft of bulk reservoir rock. This one unit, or 1 ac-ft, of bulk reservoir rock contains Connate water: 43,560 × φ × Sw ft3 Reservoir gas volume:… Continue reading Calculating Unit Recovery from Volumetric Gas Reservoirs

Calculating Hydrocarbon in Place Using Geological, Geophysical, and Fluid Property Data

In order for the reservoir engineer to calculate the amount of hydrocarbon in place from geological information, the reservoir bulk volume must first be calculated. Many methods exist to estimate the reservoir bulk volume but only two will be discussed here. The first method involves the reservoir engineer using well logs, core data, well test… Continue reading Calculating Hydrocarbon in Place Using Geological, Geophysical, and Fluid Property Data

Introduction

The contains a discussion of single-phase gas reservoirs (refer to Fig. 1.4). In a single-phase gas reservoir, the reservoir fluid, usually called natural gas, remains as nonassociated gas during the entire producing life of the reservoir. This type of reservoir is frequently referred to as a dry gas reservoir because no condensate is formed in the… Continue reading Introduction