Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
91 words
Process for the measurement of the specific flowrate in a well, as a function of time, of the various layers of a subterranean multi-layer hydrocarbon-producing formation, characterized by the fact that it consists of lowering a flowmeter (13) into the well (10), moving it successively before each of the layers (1 through 5) of the formation and recording the flowrate values it provides when located immediately above each layer and the measurement times, and then deducing the flowrate specific to each layer (1 through 5) from the cumulative flowrates thus recorded.
Claim 2
Dependent Claim
91 words
Process for the measurement of the specific flowrate in a well, as a function of time, of the various layers of a subterranean multi-layer hydrocarbon-producing formation, characterized by the fact that it consists of lowering a flowmeter (13) into the well (10), moving it successively before each of the layers (1 through 5) of the formation and recording the flowrate values it provides when located immediately above each layer and the measurement times, and then deducing the flowrate specific to each layer (1 through 5) from the cumulative flowrates thus recorded.
Claim 3
Dependent Claim
40 words
Process according to claim 1, characterized by the fact that the flowmeter (13) is repeatedly raised and lowered throughout the entire depth of the formation, so as to determine the flow variations of each layer as a function of time.
Claim 4
Dependent Claim
37 words
Process according to claim 1 or 2, characterized by the fact that a pressure gauge (16) is connected to the flowmeter (13) to provide pressure measurements in the well (10) which are concomitant with the flow measurements.
Claim 5
Dependent Claim
137 words
Process for determining the characteristic parameters of a multilayer subterranean hydrocarbon-producing formation through which a well is drilled, characterized by the fact that it consists essentially of determining the relative variations in time of the flow rates of layers or groups of layers of the formation with respect to flow rate measurement points obtained when a total flow rate variation AQ has been imposed on the well at a time t1 between a first given constant value and the second given constant value, then comparing those flow rate variations with the behavior of a theoretical model established for various values of the characteristic parameters of a subterranean formation and deducing the values of the parameters of the formation involved from those associated with the behavior of the theoretical model which best fit the experimental flow rate variations.
Claim 6
Dependent Claim
137 words
Process for determining the characteristic parameters of a multilayer subterranean hydrocarbon-producing formation through which a well is drilled, characterized by the fact that it consists essentially of determining the relative variations in time of the flow rates of layers or groups of layers of the formation with respect to flow rate measurement points obtained when a total flow rate variation AQ has been imposed on the well at a time t1 between a first given constant value and the second given constant value, then comparing those flow rate variations with the behavior of a theoretical model established for various values of the characteristic parameters of a subterranean formation and deducing the values of the parameters of the formation involved from those associated with the behavior of the theoretical model which best fit the experimental flow rate variations.
Claim 7
Dependent Claim
40 words
Process according to claim 4, characterized by the fact that well pressure values measured at the same time as the flow rates of the various layers are also used, making it possible to calculate the product permeability x formation thickness.
Claim 8
Dependent Claim
85 words
Process according to claim 4 or 5 characterized by the fact that for each layer j of the formation the variations of the fraction Δqj /ΔQ representing the ratio of flow rate variations Aqj of layer j to the variation AQ of the total well flow rate Q are determined as a function of time At, and the horizontal permeability and skin coefficient parameters kj and s j of the layer are deduced by comparing said variations Aqj/AQ with the behavior of a theoretical model.
Claim 9
Dependent Claim
64 words
Process according to claim 5 characterized by the fact that the variations of flow rate of each layer j are convoluted with the well pressure variations, which makes it possible to obtain the pressure response of the given layer as if it were alone, from which the permeability and the skin effect coefficient of the layer can be deduced using classical methods of interpretation.
Claim 10
Dependent Claim
106 words
Process according to any of claims 4 through 7 characterized by the fact that for each zone i of the formation, i.e., for each group of productive layers contained between two impermeable intermediate layers, a determination is made of the variations as a function of time, of the fraction ΣΔqi / ΔQ representing the ratio of the flow rate variations of said zone i to the variation in the total flow rate Q of the well, and the type and position of the external boundary of said zone are deduced from the comparison between said variations of said fraction and the behavior of a theoretical model.
Claim 11
Dependent Claim
60 words
Process according to any of the claims 4 through 7 characterized by the fact that the flow rate variations of each zone i are convolved with the well pressure variations to obtain the pressure response of the zone involved, from which the type and position of the external boundary of said zone can be deduced by classical methods of interpretation.
Claim 12
Dependent Claim
104 words
Process according to any of the claims 4 through 9 characterized by the fact that for each layer j of a zone i of the formation, i.e., of a group of productive layers contained between two impermeable intermediate layers, a determination is made of the variations of the fraction Aqj/AQirepresenting the ratio of the flow rate variations of layer j to the flow rate variation of zone i, and the interlayer permeability parameters of the zone involved are deduced by comparison between the said variations of the said fraction and the behavior of a theoretical model, for each of the zones in the formation.
Claim 13
Dependent Claim
41 words
Process according to any of claims 6 through 10 characterized by the fact that the curves representing the variations of said fractions are plotted and then fitted to the curves representing said theoretical model of the characteristics of the subterranean formation.
Claim 14
Dependent Claim
67 words
Process according to any of claims 4 through 11 characterized by the fact that instead of the flow rate measurements made after a relatively long lapse of time A t after the time t1 when the well flow rate is changed, the measurements made just prior to time t1 are used, where the well has been flowing for a period essentially equivalent to the aforesaid time lapse.
Claim 15
Dependent Claim
100 words
Process according to any of claims 4 through 12 characterized by the fact that the measurement of the specific flow rate as a function of time of the various layers of the formation is achieved by lowering a flowmeter (13) into the well (10) and moving it successively in front of each of the layers (1 through 5) of the formation and recording the flow rate values and time readings it provides when it is located immediately above each layer, and then deducing the flow rate specific to each layer (1 through 5) from the cumulative flow rates thus recorded.
Claim 16
Dependent Claim
24 words
Process according to claim 10 characterized by the fact that the flowmeter (13) is repeatedly raised and lowered throughout the depth of the formation.
Claim 17
Dependent Claim
36 words
Process according to claim 5 and claim 13 or 14 characterized by the fact that a pressure gauge (16) is added to the flowmeter (13) to provide well presure measurements concomitant with the flow rate measurements.
Claim 18
Dependent Claim
21 words
Process according to claim 15 characterized by the fact that said pressure gauge is in a fixed position in the well.