System and method for performing wellbore fracture operations

Abstract

A method of performing an oilfield operation about a wellbore penetrating a subterranean formation are provided. The method involves performing a fracture operation by generating fractures about the wellbore. The fractures define a hydraulic fracture network (HFN) about the wellbore. The method also involves generating a discrete fracture network (DFN) about the wellbore by extrapolating fracture data from the HFN. The DFN includes fracture branches with intersections therebetween and matrix blocks. The method also involves generating a depth of drainage through the DFN, defining production parameter(s), and performing a production operation to produce fluids from the subterranean formation based on the depth of drainage and the production parameter(s). The production operation may involve generating a flow rate through the DFN, generating a pressure profile of the DFN for an initial time based on the flow rate, and generating a production rate based on the pressure profile.

What is claimed is: 
     
         1 . A method of performing a production operation about a wellbore penetrating a subterranean formation, the subterranean formation having a plurality of fractures thereabout, the method comprising:
 generating a flow rate through a discrete fracture network, the discrete fracture network extrapolated from a hydraulic fracture network defined by the plurality of fractures in the subterranean formation, the discrete fracture network comprising a plurality of fracture branches with intersections therebetween and a plurality of matrix blocks;   generating a pressure profile of the discrete fracture network for an initial time based on the flow rate; and   generating a production rate based on the pressure profile.   
     
     
         2 . The method of  claim 1 , wherein the generating the flow rate comprises generating the flow rate from one of the plurality of matrix blocks to one of the plurality of fracture branches. 
     
     
         3 . The method of  claim 1 , wherein the generating the flow rate comprises generating the flow rate inside at least one of the plurality of fractures. 
     
     
         4 . The method of  claim 1 , wherein the generating the flow rate comprises generating the flow rate from one of the plurality of matrix blocks to one of the fracture branches. 
     
     
         5 . The method of  claim 1 , wherein the generating flow rate comprises generating flow rate inside the one of the fracture branches between two of the intersections of the discrete fracture network. 
     
     
         6 . The method of  claim 1 , wherein the generating the flow rate comprises generating the flow rate inside the one of the plurality of fracture branches at the intersections of the discrete fracture network. 
     
     
         7 . The method of  claim 1 , further comprising determining mass balance at the intersection between two of the plurality of fracture branches. 
     
     
         8 . The method of  claim 1 , wherein the generating the pressure profile comprises generating the pressure profile using Darcy's law. 
     
     
         9 . The method of  claim 1 , wherein the generating the pressure profile is unconstrained by a time step. 
     
     
         10 . The method of  claim 1 , further comprising defining a time function of fluid flow through the matrix block, the time function having the initial time. 
     
     
         11 . The method of  claim 10 , further comprising updating the time function of fluid flow through the matrix block. 
     
     
         12 . The method of  claim 1 , further comprising updating the production rate at a plurality of time steps. 
     
     
         13 . The method of  claim 1 , further comprising updating the production rate for the plurality of fracture branches. 
     
     
         14 . The method of  claim 1 , further comprising accounting for delays in production of each of the plurality of matrix blocks by updating the initial time such that an actual mass produced from each of the plurality of matrix blocks equals the mass if the current pressure conditions in an adjacent one of the plurality of fracture branches would have been constant in time from the updated initial time. 
     
     
         15 . The method of  claim 1 , further comprising validating the production rates. 
     
     
         16 . The method of  claim 15 , wherein the validating comprises comparing the production rates with production rates generated by a reservoir simulator. 
     
     
         17 . The method of  claim 15 , wherein the validating is performed for the discrete fracture network having high conductivity, low conductivity, bi-wing fractures, wire-mesh fractures, time delay, and combinations thereof. 
     
     
         18 . The method of  claim 15 , wherein the validating comprises modifying the initial time so that a volume produced from the plurality of matrix blocks over time for each of the plurality of fracture branches satisfies mass balance. 
     
     
         19 . A method of performing an oilfield operation about a wellbore penetrating a subterranean formation, the subterranean formation having a reservoir therein, the method comprising:
 performing a fracture operation, the fracture operation comprising generating fractures about the wellbore, the fractures defining a hydraulic fracture network about the wellbore;   generating a discrete fracture network about the wellbore by extrapolating fracture data from the hydraulic fracture network, the discrete fracture network comprising a plurality of fracture branches with intersections therebetween and a plurality of matrix blocks;   generating a depth of drainage through the discrete fracture network;   defining at least one production parameter; and   performing a production operation to produce fluids from the subterranean formation based on the depth of drainage and the at least one production parameter.   
     
     
         20 . The method of  claim 19 , further comprising measuring downhole data about the wellbore. 
     
     
         21 . The method of  claim 19 , wherein the performing the fracture operation comprises stimulating production from the wellbore by injecting fluid into the subterranean formation. 
     
     
         22 . The method of  claim 19 , wherein the performing the fracture operation comprises simulating the performing the fracture operation. 
     
     
         23 . The method of  claim 19 , wherein the discrete fracture network considers an averaged value for at least one fracture property at each of the plurality of fracture branches. 
     
     
         24 . The method of  claim 23 , wherein the at least one fracture property comprises spatial coordinates at a fracture branch extremity, conductivity, averaged conductivity, height, averaged height, reservoir pressure, averaged reservoir pressure at a fracture branch location, permeability, averaged reservoir permeability at the fracture branch location and combinations thereof. 
     
     
         25 . The method of  claim 19 , wherein the generating the depth of drainage comprises evaluating the depth of drainage through the plurality of matrix blocks of the discrete fracture network. 
     
     
         26 . The method of  claim 19 , wherein the generating the depth of drainage comprises generating the depth of drainage for each of the plurality of matrix blocks based on an approximation of linear flow through the plurality of matrix blocks. 
     
     
         27 . The method of  claim 19 , wherein the generating the depth of drainage comprises automatically evaluating the depth of drainage of the plurality of matrix blocks to be depleted in front of each of the plurality of fracture branches and accounting for a volume to deplete for each of the plurality of matrix blocks. 
     
     
         28 . The method of  claim 19 , wherein the at least one production parameter comprises bottom hole pressure, reservoir fluid viscosity at reservoir conditions, reservoir fluid compressibility at reservoir conditions, duration over which production is to be simulated, and combinations thereof. 
     
     
         29 . The method of  claim 19 , wherein the performing the production operation comprises positioning tubing in the wellbore and transporting fluids from the reservoir to a surface location. 
     
     
         30 . The method of  claim 19 , wherein the performing the production operation comprises estimating a production rate from the wellbore by simulating the production of fluid from the wellbore. 
     
     
         31 . The method of  claim 30 , wherein the performing a production operation comprises visualizing the production rate. 
     
     
         32 . The method of  claim 30 , further comprising adjusting the performing based on the estimated production rate. 
     
     
         33 . The method of  claim 19 , wherein the performing the production operation is based on a range of fracture parameters. 
     
     
         34 . A method of performing an oilfield operation about a wellbore penetrating a subterranean formation, the subterranean formation having a reservoir therein, the method comprising:
 stimulating the wellbore by injecting fluid into the subterranean formation such that fractures are generated about the wellbore;   measuring the fractures and defining a hydraulic fracture network based on the measured fractures;   generating a discrete fracture network about the wellbore by extrapolating fracture data from the hydraulic fracture network, the discrete fracture network comprising a plurality of fracture branches with intersections therebetween and a plurality of matrix blocks;   generating a depth of drainage through the discrete fracture network;   defining at least one production parameter; and   estimating a production rate over time based on the depth of drainage and the at least one production parameter; and   producing fluids from the subterranean formation based on the estimated production rate.