دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the percentage of the total bulk volume of a rock sample that is composed of pore spaces or voids. See porosity.

the percentage of the total bulk volume that is pore spaces, voids or fractures.

n: a rock formation that contains large open spaces, usually resulting from the dissolving of soluble substances by formation waters that may still be present. See vug.

n: A formation having columinous voids, usually the result of dissolving by formation waters which may or may not be still present.

n: The creation of voids in the cement between the casing and the borehole, thereby reducing the effectiveness of the cement bond.

the maximum flow rate that avoids damage to the pipe from corrosion or erosion.

the maximum flow rate that avoids producing sand from the formation.

a neutron-type device that evaluates the packing completeness or condition of the gravel pack. The log is useful for estimating voids in the pack.

adj: preventing the passage of fluid. A formation may be porous yet impermeable if there is an absence of connecting passages between the voids within it. See permeability.

adj: preventing the passage of the fluid through the pores of the rock.

Rock with passages so small that no effective flow can take place. Note: all manmade and natural substances have some permeability, given high pressure, time, enough surface area and a low permeability fluid.

n: 1. a type of reservoir trap composed of rock (usually limestone) formed from the shells or skeletons of marine animals. 2. a burled coral or other reef from which hydrocarbons may be withdrawn.

coral reef built deposits. Among the highest permeability reservoirs because of connected voids if there has not been extensive chemical modification.

n: cement placed in a wellbore after the primary cementing has occurred. Remedial cementing is used to repair holes in the casing, fill voids left behind in casing after primary cementing, stop lost circulation, and so on. Compare primary cementing.

n: Cementing operations performed to repair primary-cementing problems or to treat conditions arising after the wellbore has been constructed. The two main categories of remedial Cementing include squeeze cementing and the placement of cement plugs.

repair cementing.

n: a type of acoustic log that records the travel time of sounds through objects, cement, or formation rocks. Often used to determine whether voids exist in the cement behind the casing in a well bore.

a sonic log measures the interval travel time (delta t) of compression sound waves moving through one foot of a formation (milliseconds/ft). If matrix velocity is known, porosity can be calculated since sound waves travel slower in porous media (travel sl