Ingeniero Mecanico

Presentation Outline
• Formation Treatments
– – – – What are we doing? Frac packs HRWP Matrix acidizing

• Friction • ISIP
– Determining ISIP

• Calculations
– – – – Fracture PressureFracture Gradient Pmax Wellhead Treating Pressure

• Skin Factor • Formation responses during HRWP and frac packs • Step Rate Test Analysis • Circulation Test

Permeability Defined
• Ability of oil,gas and other fluids to flow through a porous media or the formation • Higher the permeability, easier for fluid to flow though formation • Permeability measured in darcies/millidarcies (md) • For theGulf Coast
– 150 md= high permeability

Gravel Pack Sand Permeability
Industry accepted values

• 20/40 Sand • 40/60 Sand • 50/70 Sand

120 darcies 45 darcies 20 darcies

One millidarcy is1/1000th of a darcy

Skin Factor or “Skin” Defined
• Numerical ratio expressing existing production compared to theoretically undamaged formation • Used as an assessment of near-wellbore damage dueto things like incompatible fluids, fines migration, unbroken fracturing gels, and proppant crushing and embedment

• Skin factor of “0” equates to an undamaged formation
• Negative skin factorindicates stimulated formation • Positive skin factor indicates damaged formation

Formation Damage
• Ideal formation • What we usually get

100 md reservoir

100 md reservoir
2 md damageWhat is a High-Rate Water Pack?
• Stimulation/packing treatments employing brines or low to medium viscosity carrier fluids, pumped at high rates, to place sand into the perforation tunnels and smallcreated fractures
• 1) High-Rate Water Pac - Treatment stays under formation fracture pressure, and only fills the perforations tunnels • 2) High-Rate Water Frac - Treatment exceeds fracture pressurefilling the perforations tunnels and also creates and packs small fractures (1’-3’ long narrow fractures)

Frac Packs
• An established method of increasing production by creating a sand filled...