What is unconsolidated reservoir?

Unconsolidated petroleum reservoirs are non-crystalline rock and include tight gas sands, heavy oil, and bitumen rich sands. These can be both near surface and at depth.

What is the difference between consolidated and unconsolidated rock?

Geologic materials can be classified as consolidated rock or unconsolidated (loose) sediment. Consolidated rock may consist of such materials as sandstone, shale, granite, and basalt. Unconsolidated sediment contains granular material such as sand, gravel, silt, and clay.

How does flow rate affect sand production?

The experimental results showed that, the magnitude of sand production from the tested porous medium is strongly affected by both flow rate and confining pressure. Sand production decreases with increasing confining pressure and/or decreasing flow rate.

Which are the different factors for sand production?

Reasons for sand production

• Degree of cementation and consolidation.
• Production rate.
• Drawdown.
• Reduction of Pore Pressure.
• Reservoir Fluid Viscosity.
• Increasing Water Production.

What is a consolidated formation?

A geologic material whose particles are stratified (layered), cemented, or firmly packed together (hard rock); usually occurring at a depth below the ground surface. Also see unconsolidated formation.

What is unconsolidated formation?

A sediment that is loosely arranged or unstratified (not in layers) or whose particles are not cemented together (soft rock); occurring either at the ground surface or at a depth below the surface. Also see consolidated formation.

What do the best groundwater reservoirs have?

Good aquifers are those with high permeability such as poorly cemented sands, gravels, or highly fractured rock. An aquitard is a body of material with very low permeability. In general, tightly packed clays, well cemented sandstones, and igneous and metamorphic rocks lacking fractures are good aquitards.

What is sweep efficiency in reservoir engineering?

1. n. [Enhanced Oil Recovery] A measure of the effectiveness of an enhanced oil recovery process that depends on the volume of the reservoir contacted by the injected fluid.

Is sand weathered?

Sand is typically made mostly of varying amounts of material weathered from inland rocks (or seacliff material) and transported to the beach on the wind or in rivers, and/or shells and other hard parts precipitated out of the ocean water by marine organisms. Sand therefore records processes at a variety of timescales.

What is a gravel pack?

Gravel packing is a sand-control method used to prevent the production of formation sand. During this operation, a steel screen is placed in the well – the well is then packed with gravel of a specific size to prevent the passage of formation sand.

What is sand production problem?

These include sand problems induced by (1) unconsolidated formations; (2) water break through for weak to intermediate strength formations; (3) reservoir pressure depletion in relatively strong formations; (4) abnormally high lateral tectonic force in relatively strong formations; and (5) sudden change in flow rate or …