Abstract: A well coring apparatus is provided with the capability for monitoring the length of the core in the inner barrel (32) of a core barrel (16) and the rate at which the core enters the inner barrel (32). The device includes a Sonic Core Monitor (78) which is disposed in the upper end of the inner barrel (32) and a piston (68) which is disposed in the lower end thereof. The inner barrel (32) is filled with a pressurized fluid. The Sonic Core Monitor (78) generates an ultrasonic pulse that is transmitted down to the surface of the piston (68) and reflected back up to the Sonic Core Monitor (78). The time between the transmitted and received pulse is then measured and distance determined therefrom. Both length of core and rate of core entry into the inner barrel (32) can then be determined. If the core is proceeding at too slow a rate, a valve (50) can be opened to allow drilling fluid to bypass the core barrel (16). This provides the surface operator with an indication that a jam has occurred.

Abstract: A well coring apparatus is provided with the capability for monitoring the length of the core in the inner barrel (32) of a core barrel (16) and the rate at which the core enters the inner barrel (32). The device includes a Sonic Core Monitor (78) which is disposed in the upper end of the inner barrel (32) and a piston (68) which is disposed in the lower end thereof. The Sonic Core Monitor (78) generates an ultrasonic pulse that is transmitted down to the surface of the piston (68) and reflected back up to the Sonic Core Monitor (78). The time between the transmitted and received pulse is then measured and distance determined therefrom. Both length of core and rate of core entry into the inner barrel (32) can then be determined. If the core is proceeding at too slow a rate, a valve (50) can be opened to allow drilling fluid to bypass the core barrel (16). This provides the surface operator with an indication that a jam has occurred.

Abstract: A method for determining the productivity of a well site includes extracting a core with sponge coring techniques and measuring the parameters of the core. The parameters measured are porosity, permeability and percent mobile oil. A core factor is calculated which is the square root of the product of permeability and porosity and indicates the space available in the core for oil production. The core factor is multiplied by the percent mobile oil to provide a Production Index. The Production Index indicates the capacity of a given oil well to produce oil. With the Production Index data, perforations are selectively placed in various areas along the longitudinal axis of a well casing (38) to selectively allow communication between the interior of the well casing and a formation of interest. In this manner, only areas having high oil mobility are communicated within a given region of the formation of interest.

Abstract: A well coring apparatus (10) includes an outer barrel (12) and an inner barrel (18). The inner barrel (18) is sealed at one end with a sealing member (80) and has a reciprocating piston (70) disposed in the other end thereof. An O-ring (68) is disposed at the receiving end of the inner barrel (18) to provide a seal therefor. Spring members (76) provide a restrictive force to the piston (70). A sponge (50) is disposed around the inner walls of the inner barrel (18) for contacting the core (82). A fluid is disposed in the inner space (78) of the inner barrel (18) and pressurized. Reciprocation upward of the piston (70) causes the fluid to flow therefrom out the receiving end of the inner barrel (18). This flow of fluid washes the sides of the core (82) to prevent drilling mud from caking about the surfaces thereof and preventing proper transfer of fluids contained within the core (82) to the sponge (50).

Abstract: An apparatus (10) and method for obtaining oil and water saturation data from subterranean formations includes a drill bit (12) for boring a well core (26) containing the fluids. A core-catcher bowl (18) guides the well core (26) in the apparatus (10). An outer barrel (14) is attached to the drill bit (12) and contains the core-catcher (18). An inner liner (20) positioned in the outer barrel (14) receives the well core (26). An oil absorbent sponge-like member (22) is contained in the inner liner (20) with a diameter (24) for receiving the well core (26). The oil absorbent sponge-like member (22) absorbs the fluids contained in the well core (26).