초록 ▼

A method for surface estimation of reservoir properties, wherein location of and average earth resistivities above, below, and horizontally adjacent to the subsurface geologic formation are first determined using geological and geophysical data in the vicinity of the subsurface geologic formation. T

A method for surface estimation of reservoir properties, wherein location of and average earth resistivities above, below, and horizontally adjacent to the subsurface geologic formation are first determined using geological and geophysical data in the vicinity of the subsurface geologic formation. Then dimensions and probing frequency for an electromagnetic source are determined to substantially maximize transmitted vertical and horizontal electric currents at the subsurface geologic formation, using the location and the average earth resistivities. Next, the electromagnetic source is activated at or near surface, approximately centered above the subsurface geologic formation and a plurality of components of electromagnetic response is measured with a receiver array. Geometrical and electrical parameter constraints are determined, using the geological and geophysical data. Finally, the electromagnetic response is processed using the geometrical and electrical parameter constraints to produce inverted vertical and horizontal resistivity depth images. Optionally, the inverted resistivity depth images may be combined with the geological and geophysical data to estimate the reservoir fluid and shaliness properties.

대표청구항 ▼

A method for surface estimation of reservoir properties, wherein location of and average earth resistivities above, below, and horizontally adjacent to the subsurface geologic formation are first determined using geological and geophysical data in the vicinity of the subsurface geologic formation. T

A method for surface estimation of reservoir properties, wherein location of and average earth resistivities above, below, and horizontally adjacent to the subsurface geologic formation are first determined using geological and geophysical data in the vicinity of the subsurface geologic formation. Then dimensions and probing frequency for an electromagnetic source are determined to substantially maximize transmitted vertical and horizontal electric currents at the subsurface geologic formation, using the location and the average earth resistivities. Next, the electromagnetic source is activated at or near surface, approximately centered above the subsurface geologic formation and a plurality of components of electromagnetic response is measured with a receiver array. Geometrical and electrical parameter constraints are determined, using the geological and geophysical data. Finally, the electromagnetic response is processed using the geometrical and electrical parameter constraints to produce inverted vertical and horizontal resistivity depth images. Optionally, the inverted resistivity depth images may be combined with the geological and geophysical data to estimate the reservoir fluid and shaliness properties. s for energizing the shaft toward the center of the mounting aperture so as to set a position of the shaft at the center of the mounting aperture, and wherein the spring member is formed of a long hoop-shaped metal plate, the plurality of tongues are in series with the base of the spring member so as to project from the base, and the spring member has a cylindrical shape due to a cutting operation on a hoop material to a length corresponding to a length in a direction of the diameter of the shaft and the cylindrical spring member is disposed so as to be wound around the shaft. 2. A rotary encoder according to claim 1, wherein, the code member is made of a magnet, and wherein a basal portion of a rising portion of the tongue notched up from the base is disposed at a position out of a thickness range in a direction of the rotation axis line of the code member. 3. A rotary encoder according to claim 1, wherein the spring member has an engaging portion projecting from an end thereof by bending generally perpendicularly, the engaging portion being latched by an end of the rotor. rain coupled to said current sensing circuit to receive said sense current, a NMOS source coupled to said ground terminal, and a NMOS gate coupled to said NMOS drain; a second n-channel MOSFET (NMOS) having a second NMOS drain, a second NMOS source coupled to said ground terminal, and a second NMOS gate coupled to said NMOS gate; a second p-channel MOSFET (PMOS) having a second PMOS drain coupled to said second NMOS drain, a second PMOS source, and a second PMOS gate coupled to said second PMOS drain, wherein said PMOS gate is coupled to said second PMOS gate; and a secondary biasing circuit coupled to said second PMOS source. 23. A low dropout voltage (LDO) regulator as recited in claim 21 wherein said capacitor includes a first terminal and a second terminal, wherein said first terminal is coupled to said ground terminal, wherein said PMOS drain is coupled to said second terminal, wherein said PMOS gate is coupled to said bias circuit such that said bias circuit biases said PMOS in a linear region, wherein said PMOS source is coupled to said output terminal of said amplifying stage, and wherein said bias parameter comprises a voltage between said PMOS gate and said PMOS source. 24. A low dropout voltage (LDO) regulator as recited in claim 15 wherein said pass device stage comprises a power p-channel