Methods And Apparatus For Planning And Dynamically Updating Sampling Operations While Drilling In A Subterranean Formation

Abstract

An example method of planning a sampling while drilling operation for a subterranean formation includes identifying a plurality of processes and related parameters, the processes including drilling and sampling processes and the related parameters including drilling and sampling parameters. The example method also involves processing the parameters for each of the processes via a simulation engine to generate predictions associated with sampling the formation, the simulation engine including at least one of a wellbore hydraulics simulator, a mudcake simulator, a formation flow simulator, or a tool response simulator. The example method also involves ranking the predictions associated with sampling the formation based on at least one of a sample fluid quality, a sampling process duration, a sampling process efficiency or a cost of sampling, and planning the sampling operation based on the ranked predictions.

1 . A method of controlling a subterranean formation sampling operation, comprising:
 testing the formation to be sampled;   measuring a response of the formation to the testing;   determining mudcake and formation parameters based on the response of the formation;   processing the mudcake and formation parameters via a simulation engine to generate simulation outputs;   determining sampling parameters based on the simulation outputs; and   controlling the subterranean formation sampling operation based on the sampling parameters.   
     
     
         2 . The method of  claim 1  further comprising controlling the subterranean formation sampling operation based on at least one of the formation parameters, at least one pump parameter, and a tool model. 
     
     
         3 . The method of  claim 1  further comprising determining an extent of infiltration of a drilling fluid filtrate into the formation to be sampled, and changing at least one of a drilling fluid flow rate or a sample fluid flow rate based on the measured response of the formation. 
     
     
         4 . The method of  claim 1  wherein the sampling parameters are associated with at least one of a sample fluid quality, a sampling process duration, a sampling efficiency, or a cost of sampling, and wherein the simulation outputs are associated with at least one of a filtration rate history, or a filtrate volume at a borehole surface. 
     
     
         5 . The method of  claim 1  further comprising identifying parameters associated with a leaking mudcake via the simulation engine, and wherein the mudcake parameters are associated with at least one of a mudcake mass, a mudcake compaction, a mudcake deposition model, a mudcake erosion model, a mudcake permeability model, or a mudcake desorption model. 
     
     
         6 . The method of  claim 1  further comprising identifying formation parameters, wherein the formation parameters are associated with at least one of a sandface pressure, an extent of mud filtrate invasion, or a spurt invasion model, and wherein the formation parameters are processed with the mudcake parameters via the simulation engine to generate the simulation outputs. 
     
     
         7 . The method of  claim 1  further comprising identifying a wellbore hydraulics model, wherein the wellbore hydraulics model is to predict at least one of a drilling fluid velocity or an annular pressure, and wherein data associated with the wellbore hydraulics model is processed along with the mudcake parameters via the simulation engine to generate the simulation outputs. 
     
     
         8 . A method of controlling a drilling operation for a subterranean formation, comprising:
 performing a sampling process on a subterranean formation;   measuring an actual response of the formation to the sampling process;   calculating via a simulation engine a theoretical response of the formation to the sampling process;   comparing the actual response to the theoretical response;   adjusting at least one of a formation property or a drilling fluid property based on the comparison; and   controlling the drilling operation based on at least one of the adjusted formation property or the adjusted drilling fluid property to improve the sampling process.   
     
     
         9 . The method of  claim 8  wherein:
 controlling the drilling operation comprises controlling in real time at least one of a drilling fluid flow rate or the travel of the bottomhole assembly; 
 controlling the drilling operation to improve the sampling process comprises at least one of increasing a sample quality, reducing a sampling time, increasing a sampling efficiency, or reducing a cost; and 
 calculating the theoretical response of the formation comprises using at least one of a formation parameter, a sampling parameter, or a drilling parameter. 
 
     
     
         10 . The method of  claim 8  wherein:
 calculating the theoretical response of the formation comprises using at least one of a formation parameter, a sampling parameter, or a drilling parameter; and 
 the method further comprises updating the simulation engine based on at least one of the adjusted formation property or the adjusted drilling fluid property. 
 
     
     
         11 . A method of performing a sampling while drilling operation, comprising:
 planning the sampling while drilling operation with a simulator, wherein the planning comprises determining drilling and sampling parameters based on simulator output data obtained prior to initiating the sampling while drilling operation;   controlling in real time a sampling process of the sampling while drilling operation with the simulator by updating simulator input data based on data obtained during at least one of the sampling process or during a drilling process performed during the sampling while drilling operation; and   controlling in real time the drilling process with the simulator to improve the sampling process by updating the simulator input data based on data obtained during the sampling process or the drilling process.   
     
     
         12 . The method of  claim 11  wherein controlling in real time the drilling process comprises adjusting at least one of a drilling speed, a drilling fluid, or a drilling fluid pumping rate.