Add functions to copy field parameters between geogrid and ertbox grid

Add documentation

docs/copy_rms_param_to_ertbox_grid.rst

@@ -0,0 +1,143 @@
+rms.copy_rms_param
+====================
+
+The RMS python job to copy petrophysical field parameters between
+geomodel grid and ERTBOX grid is used as a part of a workflow
+to update petrophysical field parameters (RMS 3D parameters) in ERT
+as a part of an assisted history matching.
+
+About the ERTBOX grid and its purpose
+--------------------------------------
+
+The ERTBOX grid is a grid with same lateral extent, orientation, location and grid resolution as
+the geogrid assuming the geogrid has close to regular grid layout laterally. The ERTBOX grid is
+a regular grid without any structure (just a box) and the geometry is not of importance. It is
+used as input to the GRID keyword in ERT config files when using FIELD keyword in ERT. The purpose
+of the grid is to ensure fixed size of the field parameters and hence also the state vectors
+(realizations in ERT). It enable the workflow to handle field parameters from multizone
+geogrids and structural uncertainty ( varying number of layers per zone due to
+top conform or base conform grid layout of zones in the geogrid or stair stepped faults) in ERT.
+The number of layers must be at least as large as the geomodel zone with
+most layers  (of the zones having field parameters to be updated in ERT). Since the number of
+layers may vary from realization to realization in the geomodel grid, the ERTBOX grid must
+have a number of layers that is as large as the largest zone in the geomodel for all realizations
+of the geomodel grid, but not larger than necessary to avoid unnecessary large state vectors,
+cpu time, memory usage and disk space usage by ERT. The ERTBOX grid is used with its fixed size
+for all field parameters for all zones and all realizations.
+
+Purpose of the function
+------------------------
+
+The copy from geogrid to ertbox grid will usually leave grid cells in ertbox undefined
+for grid cell values in ertbox that does not corresponds to any active grid cell in the geogrid.
+To avoid missing code or any other unphysical values in the ertbox, the values are extrapolated.
+The purpose is to deliver field parameters with size equal to the ertbox size (nx, ny, nz_ertbox) where all field
+parameters for all grid cells have sensible physical values also for those that may not be used.
+ERT will per today require that all realizations (all state vectors) are of same size and be consistent.
+For a field parameter F(i,j,k), all realizations of F must have exactly the same set of active and inactive grid cells,
+and this may not automatically be the case when the geogrid zones have varying number of layers or the
+geogrid has stair step faults. To handle this, a pragmatic solution is use a fixed sized help grid, the ERTBOX grid.
+The workflow is to first copy the values for a field parameter for a zone into the ERTBOX grid
+and fill the ERTBOX grid cell values (for those grid cells that is still not filled with values)
+with extrapolated values that have at least sensible
+value and not just 0 or Nan or similar 'missing' code. The field parameters are then exported to file to be read
+by ERT. This ensure that all field parameters have same size for all realizations and that ERT in
+the analysis step does not make linear combinations of field parameters where some realization have physical values
+and others have unphysical values or Nan.
+
+Input is a python dictionary with all relevant specifications:
+
+* Name of geomodel grid and ertbox grid
+* Name of petrophysical variable in the geomodel grid to used as field parameters in ERT.
+* Name of the petrophysical variable in the ERTBOX grid.
+* Typically the field name in the ERTBOX grid will be zone_name combined with variable name.
+* Grid conformity per zone.
+* Optional if a active/inactive parameter is to be created in ERTBOX grid.
+* Extrapolation method when copying from geomodel grid to ERTBOX grid.
+
+
+Example of RMS python job using this function to copy from geogrid to ERTBOX grid
+----------------------------------------------------------------------------------
+
+In this example the geomodel grid has zone *ZoneA* and *ZoneB* and the
+petrophysical parameters *P1* and *P2*. They will be copied to the ERTBOX grid
+and will get the names *ZoneA_P1*, *ZoneA_P2* and similarly for *ZoneB*. The zone
+number is specified as the key and corresponding parameters must come in the same
+order in the list for both the keyword *GeoGridParameters* and *ErtboxParameters*.
+The available keywords are:
+
+* project (The internal project variable for RMS python jobs)
+* debug_print to control printed output to screen (value 0 is no output, value 1 or 2 for more output)
+* Mode with the two options *from_geo_to_ertbox* or *from_ertbox_to_geo*
+* GeoGridParameters with list of which parameters to use per zone.
+* ErtboxParameters with corresponding parameter names in ERTBOX for each zone and parameter combination.
+* Conformity with legal values *Proportional, TopConform, BaseConform*.
+* GridModelName  specify grid model name in RMS for the geomodel.
+* ERTBoxGridName specify the name of the gridmodel used as ERTBOX grid.
+* ZoneParam specify the name of the zone parameter in the grid model for the geomodel.
+* ExtrapolationMethod specify which method to use. Implemented alternatives are *extend, repeat, mean, zero*.
+* SaveActiveParam turns on/off if a 0/1 parameter is to be created for the ERTBOX grid.
+* AddNoiseToInactive is optional and will add some small random noise to extrapolated values for grid cell values.
+
+.. code-block:: python
+
+    from fmu.tools.rms import copy_rms_param
+
+    params = {
+        "project": project,
+        "debug_level": 1,
+        "Mode": "from_geo_to_ertbox",
+        "GeoGridParameters": {
+            1: ["P1", "P2"],
+            2: ["P1", "P2"],
+        },
+        "ErtboxParameters": {
+            1: ["ZoneA_P1", "ZoneA_P2"],
+            2: ["ZoneB_P1", "ZoneA_P2"],
+        },
+        "Conformity": {
+            1: "BaseConform",
+            2: "TopConform",
+        },
+
+        "GridModelName": "Geogrid",
+        "ZoneParam": "Zone",
+        "ERTBoxGridName": "ERTBOX",
+        "ExtrapolationMethod": "repeat",
+        "SaveActiveParam": True,
+        "AddNoiseToInactive": True,
+    }
+    copy_rms_param(params)
+
+The next example will copy from the ERTBOX grid to the geomodel grid.
+This corresponds to using the *from_ertbox_to_geo* mode instead.
+In this case the keywords *SaveActiveParam. AddNoiseToInactive,ExtrapolationMethod* are not used.
+
+.. code-block:: python
+
+    from fmu.tools.rms import copy_rms_param
+
+    params ={
+        "project": project,
+        "debug_level": 1,
+        "Mode": "from_ertbox_to_geo",
+        "GeoGridParameters": {
+            1: ["P1", "P2"],
+            2: ["P1", "P2"],
+        },
+        "ErtboxParameters": {
+            1: ["ZoneA_P1", "ZoneA_P2"],
+            2: ["ZoneB_P1", "ZoneB_P2"],
+        },
+        "Conformity": {
+            1: "BaseConform",
+            2: "TopConform",
+        },
+
+        "GridModelName": "Geogrid",
+        "ZoneParam": "Zone",
+        "ERTBoxGridName": "ERTBOX",
+    }
+    copy_rms_param(params)
+
+aps_fmu_tools

docs/index.rst

@@ -20,6 +20,7 @@ Contents:
    generate_bw_per_facies
    update_petro_real
    export_and_import_fields
+   copy_rms_param_to_ertbox_grid
    utilities
    rmsvolumetrics2csv
    ensembles

src/fmu/tools/rms/__init__.py

@@ -2,6 +2,7 @@
 Initialize modules for use in RMS
 """
 
+from .copy_rms_param_to_ertbox_grid import copy_rms_param
 from .generate_bw_per_facies import create_bw_per_facies
 from .generate_petro_jobs_for_field_update import (
     main as generate_petro_jobs,
@@ -22,4 +23,5 @@
     "update_petro_parameters",
     "import_updated_field_parameters",
     "export_initial_field_parameters",
+    "copy_rms_param",
 ]