Reservoir Characterization: A Crucial Step in the Upstream Industry

Reservoir Characterization: A Crucial Step in the Upstream Industry

The world won’t see a shortage of petroleum in the next few decades, says the Massachusetts Institute of Technology (MIT) Technology Review. The challenge, however, lies in making up for the dwindling easy-to-extract oil supplies.

From 2010 to 2030, the supply from conventional sources would only rise from 79 million to 85 million barrels a day. The demand, in contrast, would rise from 86 million to 106 million barrels per day. This means that the petroleum industry needs to invest in operations that extract oil from less-accessible locations like those in deep reservoirs below the ocean floor. 

These explorations are more expensive and riskier than their predecessors. Oil and gas companies need sound data of their drilling project to minimize the risks, secure a high probability of success, and maximize the production of these new oil wells.

If you want to venture into these endeavors, then we highly recommend reservoir characterization.

Understanding Reservoir Characterization

Reservoir characterization refers to a model of a reservoir that integrates important information related to the production and storage of hydrocarbons. Oil and gas professionals gather different sets of data to give your team a complete picture of a reservoir’s capacities and hazards. It also helps you understand how various parts of the reservoir would behave under different circumstances. 

The Crucial Step in Exploration

As mentioned earlier, a reservoir characterization is one of the most important steps in exploration. It shows you the potential and the risks of the proposed drilling site. A good reservoir model allows you to make sound management decisions and create a production plan that would extract the most crude oil or natural gas.

Additionally, it helps your team project the costs and profits, compare a reservoir’s advantages with those of alternatives, and evaluate equity shares among partners. An extensive reservoir characterization also indicates the optimum number of wells, their locations, and designs. Lastly, it lets your team conduct a risk assessment that would shape the facilities, operations, and human resources.

A Multidisciplinary Approach

The Handbook of Petroleum Exploration and Production explains that the methods for reservoir characterization over the last 15 years has improved dramatically. Initially, the process involved only a simple engineering evaluation.

Thanks to the development of better tools and software, experts now produce more accurate reports and models. Moreover, modern reservoir characterization encompasses various disciplines and teams of experts in their fields, including:

  • Geology – This allows your team to understand a reservoir’s physical structure, like its porosity (the fraction of empty spaces, which may contain water, air, and hydrocarbons, and the total volume of the rock) and the sedimentary basins it covers. Geological data also shows the optimal well paths and helps your team steer clear of danger.
  • Geomechanics – This describes the strength of a reservoir’s rocks and soil and their response to stress, like drilling operations. Geomechanics also uncovers the geological and tectonic characteristics of various areas of the reservoir to ensure the creation of an oil well.
  • Geochemistry – This analyzes the cores (samples of a naturally occurring substance) and fluids in the reservoir to determine their richness, quality, and thermal maturity. Geochemical data also reveals the source of the hydrocarbons, the interaction of the fluids and rocks, potential migration pathways, and the optimum timing of petroleum migration.
  • Geostatistics – While traditional geology involves qualitative characteristics, geostatistics relies heavily on numerical data. A geostatistics report helps your team understand the spatial variables of the reservoir, including its heterogeneity (the variation of rock properties) and directionality.
  • Biostratigraphy – This studies the fossil assemblages within the various layers (strata) of rocks in the reservoir. The information it provides, such as lithologic descriptions, log signatures, and seismic features, allows your team to monitor drilling operations more efficiently. Moreover, oil companies focused on deltaic reservoirs can use the biostratigraphic information to locate other deltas in the region.
  • Petrophysics – This investigates the physical and chemical properties of a reservoir’s rocks and fluids. It produces information vital to making economic projections and decisions, such as the fluid saturation, fluid pressure, permeability, and fractional flow of oil, gas, and water.
  • Petroleum Engineering – This discipline examines various activities related to the production of crude oil and natural gas. Largely focused on the upstream industry, petroleum engineering estimates the volume of recoverable hydrocarbons, determines the most efficient drilling methods, and oversees profitable production.

Invaluable Data from Reservoir Characterization

A reservoir characterization incorporates data that’s invaluable to exploration and development. Some of these include:

  • 3D Structural Model – This shows the framework of a reservoir, including the bounding surfaces, faults affecting fluid flow, the relationships between faults, and the contact between faults and bounding surfaces. A 3D structural model also lets your team find the ideal locations for drilling and well creation.
  • Stratigraphic Model – This depicts bedding geometries and the different strata of facies (the characteristics of a rock that distinguish it from others). A stratigraphic model helps your team understand turbidites (sedimentary deposits formed by turbidity currents at the base of a continental slope) and locate stratigraphic traps (sealed geological pockets formed by changes in rocks and reefs that may contain hydrocarbons). These pieces of information pave the way for more precise oil and gas migration pathways.
  • Facies Model – This provides additional information on the facies in a reservoir, which can predict fluid behavior. A facies model includes a rock’s mineralogy, sedimentary source, fossil content, texture, and structure.
  • Petrophysical Model – This explores rocks’ petrophysical characteristics, such as porosity, saturation, permeability, shale and clay volume, heterogeneity, anisotropy, net pay, and more. These help your team evaluate new wells and manage the reservoir more efficiently.
  • Volumetrics – This estimates the volume of hydrocarbons in the reservoir. To compute volumetrics data, experts take area, rock porosity, reservoir pressure, water saturation, oil formation volume, and more into account. Experts usually source these data sets from core samples, wireline logs, and geological maps.

An Expert in Reservoir Characterization

Reservoir characterization is a crucial step in the upstream industry because it helps oil and gas companies get the most out of crude oil reserve. In this arena, it pays off to partner with a trusted geoservice company.

Sierra Pine Resources International is a team of oil and gas professionals dedicated to improving upstream processes. We have decades of experience in conducting reservoir characterizations, and we have helped countless companies maximize crude oil and natural gas extraction.

We’ll help you make the most of your exploration project. Call us at (832) 375-0300 or visit our headquarters for an obligation-free consultation.