Method and system of monitoring a hydrocarbon reservoir

Abstract

The invention provides a method and system of estimating a static pressure of one or more influx zones to a production well. The method comprises arranging at least one tracer source with distinct tracer materials in known levels of the well; inducing production flow in the production well for at least two different flow rates and collecting at least one sample downstream of the one or more influx zones for each flow rate. The method comprises measuring a bottom hole pressure for each flow rate, analysing the at least one sample for the presence or absence of tracer and based on the tracer data and bottom hole pressure data estimating a static pressure for the one or more influx zones.

1 . A method of estimating static pressure of one or more influx zones or influx locations to a production well;
 wherein the well comprises tracer sources with distinct tracer materials in known levels of the well, the method comprises:   inducing production flow in the production well for at least two different flow rates;   collecting at least one sample downstream of the one or more influx zones for each flow rate;   measuring a bottom hole pressure for each flow rate;   analysing the at least one sample for the presence or absence of tracer;   based on the tracer data and bottom hole pressure data estimating a static pressure for the one or more influx zones.   
     
     
         2 . The method according to  claim 1  wherein the one or more influx zones are from the same reservoir, different layers of the same reservoir, different reservoirs, different layers of different reservoirs and/or one or more laterals in the same wellbore. 
     
     
         3 . The method according to  claim 1  comprising estimating the static pressure of one or more influx zones of a multilayer reservoir to a production well or one or more influx zones of a multilateral well to a production well. 
     
     
         4 . The method according to  claim 1  comprising measuring the bottom hole pressure using a pressure measurement apparatus. 
     
     
         5 . The method according to  claim 1  comprising modifying, changing and/or adjusting the production flow rate by operation of a choke connected to the production tubing. 
     
     
         6 . The method according to  claim 1  comprising adjusting the production flow rate until at least one tracer is not detected in the at least one sample or adjusting the production flow rate until at least one tracer is first detected in the at least one sample. 
     
     
         7 . The method according to  claim 1  comprising estimating, calculating and/or monitoring a composite productivity index for the zones of the well and/or calculating and/or estimating a productivity index for each zone. 
     
     
         8 . The method according to  claim 1  comprising analysing the at least one sample for type of tracer and/or concentration of tracer. 
     
     
         9 . The method according to  claim 1  comprising installing, placing or positioning the tracer sources with distinct tracer materials at each influx zone. 
     
     
         10 . The method according to  claim 1  comprising measuring the flow rate of the production flow. 
     
     
         11 . The method according to  claim 1  comprising estimating, calculating, monitoring and/or determining a static pressure for each zone. 
     
     
         12 . The method according to  claim 1  comprising estimating, calculating, monitoring and/or determining the contribution of flow from two or more influx zones. 
     
     
         13 . The method according to  claim 11  comprising estimating, calculating, monitoring and/or determining the contribution of flow from zones in two or more laterals. 
     
     
         14 . The method according to  claim 1  comprising identifying static pressure gradients along the well at one or more influx zones. 
     
     
         15 . The method according to  claim 1  comprising mapping the static pressures for each influx zone, each influx zone in each lateral of the well and/or each lateral of the well. 
     
     
         16 . The method according to  claim 1  comprising estimating, calculating, monitoring and/or determining a static pressure difference between two or more zones of a multilayer reservoir and/or two or more influx zones of a multilateral well. 
     
     
         17 . The method according to  claim 1  comprising inferring information on the amount and/or volume of hydrocarbon in each zone based on zonal static pressure data. 
     
     
         18 . The method according to  claim 1  comprising identifying depleted zones based on the zonal static pressure data. 
     
     
         19 . The method according to  claim 1  comprising creating a reservoir model wherein the model comprises one or more parameters selected from the group comprising zone location, production flow rate, productivity index for the well, productivity index for each zone, static pressure of each zone, flowing bottom hole pressure, pressure difference between static pressure of each zone and flowing bottom hole pressure, total influx volume of the well, influx volume of each zone, petrophysical data of the well and/or core data of the well. 
     
     
         20 . The method according to  claim 19  comprising comparing modelled static pressure of one or more zone with measured static pressure of one or more zones. 
     
     
         21 . The method according to  claim 19  comprising adjusting one or more parameters until the modelled data best fits the measured data. 
     
     
         22 . A system for estimating the static pressure of one or more influx zones or influx locations to a production well with one or more influx zones or influx locations to a production flow, the system comprising:
 at least one tracer source with distinct tracer material configured to be installed in known levels of the well;   a pressure measurement device configured to measure bottom hole pressure;   a choke assembly configured to adjust the production flow rate to at least two different flow rates; and   at least one sampling device configured to collect at least one sample of well fluid downstream of a one or more influx zones.   
     
     
         23 . The system according to  claim 22  wherein the sampling device is configured to collect or take samples at one or more sampling times. 
     
     
         24 . The system according to  claim 22  wherein the sampling device is configured to collect or take samples for further analysis onsite or offsite. 
     
     
         25 . The system according to  claim 22  wherein the system comprises a processor configured to estimate, calculate and/or determine a static pressure for an influx zone based on the tracer data and identifying a bottom hole pressure where the influx zone starts and/or stops flow to a production well.