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Optimal Reservoirs is a rapidly growing services and consulting company specializing in technically demanding, high-value upstream oil and gas projects. Because of our specialization and focus, we work on some of the highest-profile and most challenging assignments in the industry. To do so, we have experienced, talented people with a strong desire to learn and contribute.

We provide the following services and consultancy:

Advanced Fractured Reservoirs studies


Seismic Processing and interpretation


Reservoir Engineering


Geological and Geophysical Engineering

A significant relation between hydraulically conductive structures and fault and fractures with respect to the current stress field. The hydraulically highly conductive structures are critically stressed faults. They are characterized by a component of high shear stress.

Critically stressed fractures affect permeability in rocks with relatively low matrix porosity. In reservoirs with low matrix permeability, there might be no significant fluid flow in the absence of permeable fractures and faults. Moreover, it is frequently the case that relatively few fractures and faults serve as the primary conduits for flow. The faults that are hydrologically conductive today are those that are critically stressed in the current stress field. It is important to have a criterion that allows us to determine which of the faults are hydrologically conductive today. The critically-stressed-fault hypothesis suggests that faults that are mechanically active are hydraulically active and faults that are mechanically dead are hydraulically dead.


a) Seismic cross section with clear fault zones


d) Factures for short small scale faults (with minimal displacements) show high intensities in the country rocks. e) Fractures for long small scale faults show high intensities along fault zones. With a high likelihood of more faults displacements, critically stressed and hydraulically conductivity. High intensities present good reservoirs.

Sweet spot is an informal expression for a target location that represents the best probable production enable wellbores to be placed in the most productive areas of the reservoir. 

How do we select our best places to drill?

We need to explain the whole system; we need to go beyond finding high-quality reservoir. Commerciality of gas is generally associated with areas of enhanced reservoir quality, known as ‘sweet spots’.


These are areas of enhanced porosity and permeability thought to be controlled by:

1)                  Depositional trends of enhanced porosity and permeability; 

2)                  Enhanced natural fracturing, hence increased permeability; or 

3)                  Over pressuring and improved reservoir properties in a pressure compartment. 


Identification and mapping of sweet spots can be facilitated by advanced 3D seismic mapping techniques and detailed reservoir characterization.


For accurate sweet spots identification the following key risk factors are needed to be calculated


Key Geological Factors

TOC & Maturity

Thickness & Areal extent

Lithological heterogeneity, porosity


Gas content (free + adsorbed)


Key Engineering Factors


Reservoir Pressure

Gas composition & Geomechanics

Stimulation effectiveness

Well performance


Key Economic Factors

Gas Price

Access to gas market


Environmental factors

Tax incentives & lease terms 



The following are examples for sweet spots in fractured basement and carbonate reservoirs

Top seals trap and accumulate migrating hydrocarbons and commonly involve very low porosity rocks. Effective seals for hydrocarbon accumulations are typically thick, laterally continuous, ductile rocks with high capillary entry pressures. Seals need to be evaluated at differing scales. Fracturing the top seal can mechanically breach the reservoir and leave hydrocarbons behind.

Our Seal Integrity Analysis service allows assess the possibility of a top-seal breach using seismic and geologic information available during the exploration phase of a project. Consideration of subsurface hydrocarbon seals should therefore have a high priority in an exploration program. The analysis may target a specific reservoir, or may be completed regionally to better understand the possibility of maintaining a commercial hydrocarbon store in an area.


Brittle failure is the most common cause of the loss of top seal integrity.A consideration of the basic requirements for a sealing surface to a prospect can contribute to the proper judgment on the likelihood of occurrence of a seal. Studying seal risk allows a more intelligent choice among alternative exploration prospects. Fracture intersection mapping only the top seal help locate fractures along the top seal.


In damaged zones, cracks and geological faults generally have a great effect on the effective permeability of rock masses. One of the most important characteristics of naturally fractured rocks for simulating the flow in the hydrocarbon reservoir is permeability. Mapping fracture networks and estimating their properties such as porosity and permeability to be used as input data in simulation studies are two critical steps in modeling of fractured reservoirs.
Optimal Reservoirs’ Fault Damage Zone fracture network and associated Conduit Mapping is a deterministic method. We providing a reliable solution for structurally related conduits in fractured reservoirs mapping and characterization, using 3D seismic data. These conduits is identified and mapped by a three dimensional adaptive, multi-directional, multi-component logical operator. Mapping structurally related conduits, is lowering exploration and development costs.

Mapping small faults intersections can provide considerable information about fault damaged zones delineation and their associated conduits for fluid flow. These points of intersections are suitable indicators for conduit mapping because of the following reasons:

They strongly influence solute dispersion and channeled transport.

They integrate and focus the flow of liquid within a fracture network.

They have continuous flow behavior because of the enhanced capillary barrier effects and the connectivity of fracture networks, generally measured in terms of fracture intersections, because circulating flow in local flow cells arises from the interplay between distributed hydraulic potential along fracture intersections and no-flow fracture edges. Flow and transport in three dimensional fracture intersections may contribute to the re-distribution of solute.

We are targeting only damage zones and associated fracture network

Identify small faults intersections

Connected small faults intersections traces  a conduit


The final traced conduits  are the effective fluid flow path ways in
Fractured network


Identify fracture network with flow intensities along shear zone