Oil and Gas Reservoir Characterization: A Synopsis

Oil and Gas Reservoir Characterization: A Synopsis

Oil and gas companies often turn to petroleum reservoir characterization to find available hydrocarbon sources. Characterization may include seismic surveys to locate and determine the size of a reservoir. It may also include wireline services to evaluate the reservoir’s rock formation and oil and gas production.

Petroleum reservoir characterization is not only valuable in resource discovery, though. The process is also practical for reservoir management and developmental planning. It is of significant help during the analysis of oil and gas samples, as well as of petroleum extraction.

Analyzing Oil and Gas Samples through Reservoir Characterization

Oil and gas reservoir characterization, in layman’s terms, refers to the chemical fingerprinting of hydrocarbon samples from petroleum reservoirs. It is the geochemical analysis of oil and gas samples, providing a precise description of hydrocarbon composition.  

Petroleum reservoir characterization simulates hydrocarbon behavior under several circumstances. It examines various concepts such as petrophysics, facies, sequence-stratigraphics, and the petroleum system to introduce a comprehensive oil and gas reservoir analysis. As such, it presents relevant industry-related data such as reservoir continuity and petroleum production allocation.

More often than not, petroleum reservoir characterization utilizes computer modeling for the improvement of hydrocarbon estimation and developmental decision-making. The models may even predict future petroleum production and assess alternative reservoir management set-ups.

Computer modeling presents a thorough breakdown of reservoir rocks and hydrocarbon through the accurate measurement and characterization of petrophysics, geology, geomechanics, and geophysics. For this reason, geologists, geophysicists, engineers, and executives alike rely on it to make meticulous interpretations and strategic decisions that will benefit the industry and its oil and gas companies.

Extracting Petroleum from Conventional and Unconventional Reservoirs

An oil and gas reservoir is essentially a naturally occurring storage area of hydrocarbons. It is a series of permeable and porous rock formations that hold natural oil and gas. It has two broad classifications: conventional and unconventional.

In conventional reservoirs, hydrocarbons naturally expand because of the pressure difference between source rocks and reservoir rocks. Overlying semi-permeable rock formations keep the natural gas and oil trapped.

Alternatively, unconventional reservoir rocks are highly porous and less permeable. The hydrocarbons remain trapped in place. They do not require a cap rock but are more difficult to extract. Fortunately, technology continues to find ways to extract natural oil and gas from these rock formations.

In addition to natural reservoirs, players in the petroleum industry have created artificial gas reservoirs. These reservoirs serve as an underground storage to hold oil and gas until seasons of peak petroleum consumption.

The oil and gas industry constructs computer models of petroleum reservoirs, regardless of which type, for reservoir characterization. The models let oil and gas companies know precisely what is in the reservoir and how the industry can maximize the benefits, enabling them to be more confident in petroleum extraction.

Sierra Pine Resources International has several case studies available for download with real-world solutions to some of the most challenging geology facing some of the largest oil and gas companies operating in the industry.