Generating input data for simulating reservoirs with variable fluid contact depths

1 . A computer-implemented method for generating data used to simulate properties of a target area in a subterranean region, the method comprising:

controlling a data acquisition system for obtaining data characterizing a water-hydrocarbon interface of the target area;

determining control parameters for processing the data, based on a formation mechanism involved in generating the water-hydrocarbon interface;

determining by the simulation engine, an objective function that measures a delta between first values observed in the data and second values from simulations of the target area;

based on an output of the objective function, calculating, by the simulation engine, values for each of the control parameters that minimizes the delta between the first values observed in the data and the second values from simulations of the target area, wherein calculating values for each of the control parameters comprises:

identifying a steady-state pressure equation that constrains data optimization to a steady-state of the target area by removing accumulation terms from the steady-state pressure equation;

determining a respective value for a boundary condition and an initial condition of the target area; and

solving the steady-state pressure equation using the respective values for the boundary condition and initial condition;

generating, by the simulation engine, input data to simulate properties of the target area based on the values for each of the control parameters that minimizes the delta between the first values observed in the data and the second values from simulations of the target area;

performing a simulation of a target water saturation field in accordance with the selected control parameters and generated input data; and

controlling drilling operations based on an outcome of the simulation of the target water saturation field.

2 . The method of claim 1 , further comprising:

performing inference computations to obtain a dataset for a steady-state simulation, wherein the dataset comprises delta measurements of the objective function; and

based on the delta measurements, performing iterative optimization to minimize a delta between a first value observed in the data and a second value from the particular simulation of the target area.

3 . The method of claim 2 , wherein calculating values for each of the control parameters comprises:

calculating values for each of the control parameters that produce a particular simulation result corresponding to a smallest delta between observed interface data and simulated data, based on the iterative optimization.

4 . The method of claim 1 , further comprising:

regularizing the data based on a type of input data to be generated; and

selecting one or more of the control parameters based on regularized data.

5 . The method of claim 1 , wherein selecting the control parameters comprises:

determining a plurality of formation mechanisms that affect a topology of the water-hydrocarbon interface;

selecting, from the plurality of formation mechanisms, a set of formation mechanisms to model properties of the water-hydrocarbon interface; and

selecting the control parameters based on the set of mechanisms.

6 . The method of claim 5 , wherein the set of formation mechanisms comprises one or more of:

spatially varying capillarities,

spatially varying hydrodynamic pressures,

spatially varying fluid densities; and

spatially varying temperatures.

7 . The method of claim 1 , wherein the control parameters correspond to one or more of:

capillary pressure curves,

pressure-related boundary conditions of the target area, and

temperature-related boundary conditions of the target area.

8 . The method of claim 1 , wherein the water-hydrocarbon interface has a spatially varying depth.

9 . The method of claim 8 , wherein the water-hydrocarbon interface has a spatially varying depth at steady-state.

10 . The method of claim 1 , wherein:

the target area in the subterranean region is a hydrocarbon reservoir; and

the data describes a topology of the water-hydrocarbon interface prior to injection of fluids from the hydrocarbon reservoir or production of fluids from the hydrocarbon reservoir.

11 . A system for generating data used to simulate properties of a target area in a subterranean region, the system comprising a processing device and a non-transitory machine-readable storage device storing instructions that are executable by the processing device to cause performance of operations comprising:

controlling a data acquisition system for obtaining data characterizing a water-hydrocarbon interface of the target area;

determining control parameters for processing the data, based on a formation mechanism involved in generating the water-hydrocarbon interface;

determining by the simulation engine, an objective function that measures a delta between first values observed in the data and second values from simulations of the target area;

based on an output of the objective function, calculating, by the simulation engine, values for each of the control parameters that minimizes the delta between the first values observed in the data and the second values from simulations of the target area, wherein calculating values for each of the control parameters comprises:

identifying a steady-state pressure equation that constrains data optimization to a steady-state of the target area by removing accumulation terms from the steady-state pressure equation;

determining a respective value for a boundary condition and an initial condition of the target area; and

solving the steady-state pressure equation using the respective values for the boundary condition and initial condition;

generating, by the simulation engine, input data to simulate properties of the target area based on the values for each of the control parameters that minimizes the delta between the first values observed in the data and the second values from simulations of the target area;

performing a simulation of a target water saturation field in accordance with the selected control parameters and generated input data; and

controlling drilling operations based on an outcome of the simulation of the target water saturation field.

12 . The system of claim 11 , further comprising:

performing inference computations to obtain a dataset for a steady-state simulation, wherein the dataset comprises delta measurements of the objective function; and

based on the delta measurements, performing iterative optimization to minimize a delta between a first value observed in the data and a second value from the particular simulation of the target area.

13 . The system of claim 12 , wherein calculating values for each of the control parameters comprises:

calculating values for each of the control parameters that produce a particular simulation result corresponding to a smallest delta between observed interface data and simulated data, based on the iterative optimization.

14 . The system of claim 11 , further comprising:

regularizing the data based on a type of input data to be generated; and

selecting one or more of the control parameters based on regularized data.

15 . The system of claim 11 , wherein selecting the control parameters comprises:

determining a plurality of formation mechanisms that affect a topology of the water-hydrocarbon interface;

selecting, from the plurality of formation mechanisms, a set of formation mechanisms to model properties of the water-hydrocarbon interface; and

selecting the control parameters based on the set of mechanisms.

16 . The system of claim 15 , wherein the set of formation mechanisms comprises one or more of:

spatially varying capillarities,

spatially varying hydrodynamic pressures,

spatially varying fluid densities; and

spatially varying temperatures.

17 . The system of claim 16 , wherein the control parameters correspond to one or more of:

capillary pressure curves,

pressure-related boundary conditions of the target area, and

temperature-related boundary conditions of the target area.