3d estimation
3d estimation performs parameter estimation using kriging and other methods to map 3D analytical data onto volumetric grids defined by the limits of the data set, or by the convex hull, rectilinear, or finite-difference grid extents of a geologic system modeled by gridding and horizons. The module provides several convenient options for pre- and post-processing input parameter values, and allows the user to consider anisotropy in the medium containing the property.
3d estimation also has the ability to create uniform fields, and allows the user to choose which data components to include in the output. Uniform fields require no geologic input and Adaptive Gridding must be turned off (otherwise the connectivity is not implicit).
The DrillGuide functionality produces a new input data file with a synthetic boring at the location of maximum uncertainty calculated from the previous kriging estimates, which can then be rerun to find the next area of highest uncertainty. There are no limits to the number of cycles that may be run.
Variogram Options:
There are three variogram options:
- Spherical: the default and recommended choice for most applications
- Exponential: generally gives similar results to Spherical and may be superior for some datasets
- Gaussian: notoriously unstable, but can “smooth” your data with an appropriate nugget. Without a nugget term, Gaussian is generally unusable. If Gaussian kriging is overshooting the plume in various directions, the nugget is likely too small; if the plume looks overly smooth, the nugget is likely too big.
The “Power Factor” is only used for exponential or Gaussian variograms. The default value of 3 is the most common value for exponential. For Gaussian, 2 is most common, though values from 0.1 to 3 are typically acceptable.
Advanced Variography Options:
3d estimation supports complex directional anisotropic variography. The variogram is displayed as an ellipsoid that can be distorted to represent primary and secondary anisotropies and rotated to represent heading, dip, and roll. Overall scale and translation are provided as visual aids to compare the variogram to the data, though these do not affect the actual variogram.
Ports
| Direction | Name | Type | Description |
|---|---|---|---|
| Input | Input Geologic Field | Field | The main geologic field input for the module. |
| Input | Input External Grid | Field | A field containing an external grid to use for the output. (Advanced Version Only) |
| Input | Input External Data | Field | A field containing external data to use instead of reading a file. (Advanced Version Only) |
| Input | Input Filename | String | File used to estimate analytical data. |
| Output | Output Filename | String | File used to estimate analytical data. |
| Output | Output Field | Field | The main output field with analytical data added. |
| Output | Status Information | String | Text containing the full status information output from the module. |
| Output | Output Object | Renderable | A renderable object displaying the uncertainty sphere(s) and variography created by the module. Output even when Allow Run is off. |
| Output | Analytical Grid Data | Realization | Information required for direct exporting of raw analytical grid data. |
| Output | Interpolation Options | Interpolation Options | Information about the interpolation settings such as variogram parameters and number of points used in interpolation. |
Properties
| Property | Type | Description |
|---|---|---|
| Allow Run | Boolean | Controls whether the module will run when applications are loaded or data changes. When on, the module runs when applications are loaded or the Execute button is pushed. When off, the module will not run unless Execute is pressed. |
| Filename | File | The file containing the data to interpolate onto the created grid. |
| Data Component | Integer | Selects which property value in the analyte file will be kriged. The default value of -1 results in kriging of all data components in the file. |
| Execute | Button | Forces the module to run. If pressed and the application saved, the module will run when the application is loaded. |
| Z Scale | Double | The vertical exaggeration to apply to the variogram and the uncertainty sphere. |
Grid Settings
| Property | Type | Description |
|---|---|---|
| Grid Coordinates | Coordinates | Defines the coordinate domain within the data set in which kriging will be completed. Min and Max values are only used when the Rectilinear option is selected. |
| X Resolution | Integer | The number of grid nodes in the model horizontal domain. |
| Y Resolution | Integer | The number of grid nodes in the model vertical domain. |
| Z Resolution | Integer | The number of grid nodes in the model elevation domain. |
| Layers From Geology | Choice: Make Single Layer, Use all Horizons | Used with the input geology port. Controls whether to create a single layer or a layer for each horizon. |
| Min Cells Per Layer | Integer | The minimum number of cells in the Z direction per layer. Used when proportionally gridding an input geologic grid. |
| Cells Per Layer | Integer | The number of cells in the Z direction per layer when not using proportional gridding. |
| Proportional Gridding | Choice: Cells Per Layer, Proportional Z Resolution | When multiple geologic layers exist, apportions cells to layers in Z based on each layer’s average thickness, subject to the Min Cells Per Layer parameter. |
| Grid Type | Choice: Non-Explodable, Standard | The type of grid to create for interpolation. A Standard grid produces one cell set per geologic layer, allowing layers to be separated with Explode and Scale. A Non-Explodable grid produces a single, more memory-efficient grid which cannot be exploded. |
| Adaptive Gridding | Boolean | Refines the grid automatically to place grid nodes at all measured data points, ensuring the output honors all measured locations exactly. |
| Adaptive Gridding Limit | Integer | Turns off adaptive gridding when the number of sample points exceeds this value. |
| Adaptive Value Priority | Choice: Favor Min Values, Favor Max Values | Specifies the criteria for which sample to use for adaptive gridding when more than one sample is contained by the same grid cell. |
| Max Points Per Cell | Integer | The maximum number of sample points that can be inserted into a single grid cell during adaptive gridding. Higher values produce finer refinement around clustered samples. |
| Min Layer Thickness | Double | The smallest vertical height of each cell. |
| Reverse Surface Hierarchy | Boolean | Defines layers starting from the bottom to the top. |
| Boundary Offset | Double | Creates a domain larger than the input data along all three axes. |
Data Processing
| Property | Type | Description |
|---|---|---|
| Data Processing | Choice: Linear Processing, Log Processing | Allows the module to be run in either linear or log space. |
| Data Scaling | Double | A value by which all nodal data values will be multiplied before kriging. |
| Pre Clip Min | Double | Any nodal property value less than this number will be replaced during preprocessing. |
| Pre Clip Max | Double | Any nodal property value greater than this number will be replaced during preprocessing. |
| Less Than Multiplier | Double | Applied when reading a file with values flagged with the ‘<’ character. Multiplies the file value by this multiplier. |
| Detection Limit | Double | Affects file values set with the ‘ND’ or other non-detect flags. The module inserts a value equal to (Detection Limit * Less Than Multiplier). |
| Post Clip Min | Double | The smallest nodal value that will be present in the output data field. |
| Post Clip Max | Double | The largest nodal value that will be present in the output data field. |
| Auto Exponentiate External Log Data | Boolean | Detects if data imported via the External Data port has been log processed and exponentiates it, avoiding double log processing. |
| External Data | Multi-select | Selects which data components from the External Data port to use for interpolation. |
Krig Settings
| Property | Type | Description |
|---|---|---|
| Estimation Type | Choice: Kriging, IDW (Shepard), IDW (Franke/Nielson), Nearest Neighbor, FastRBF | The method for interpolating file data onto the created grid. |
| Reach | Double | The radial distance from any given model node that the module will look for data points. Setting to 0 causes the module to calculate a reach approximately two-thirds of the longest distance between any two data points. |
| Points In Reach | Integer | The maximum number of data points within the reach to consider for parameter estimation at a model node. |
| Octant Search | Boolean | When selected, searching is performed for each of the eight octants surrounding the point to be kriged. |
| Use All Points | Boolean | Causes the module to include samples up to the All Points Limit value. If the number of samples exceeds the limit, Reach and Points In Reach settings are used. |
| All Points Limit | Integer | The maximum number of points to use when interpolating. If there are more samples than this value, Reach and Points In Reach settings will be used. |
| Statistical Confidence Tolerance | Double | Specifies the interval in linear space around the kriged model estimates to which the kriging confidence or uncertainty applies. |
| Statistical Confidence Factor | Double | Specifies the interval in log space around the kriged model estimates to which the kriging confidence or uncertainty applies. |
| Min Max Confidence | Double | Specifies the interval around the kriged model estimates to which the kriging confidence or uncertainty applies. |
| IDW Power | Double | Used with Inverse Distance Weighting. Greater values increase the influence of values closest to the interpolated point. |
| Variogram And Anisotropy | Variogram | Controls the semi-variogram model and 3D anisotropy settings for kriging. |
Variography Display
| Property | Type | Description |
|---|---|---|
| Display Variogram Ellipsoid | Boolean | Displays the variography ellipsoid in the viewport. |
| Ellipsoid Opacity | Double | Sets the opacity of the ellipsoid. |
| Resolution | Integer | The resolution of the ellipsoid. Larger numbers create more detailed representations. |
| Ellipsoid Scale | Double | Scales the ellipsoid equally along each axis. |
| X Offset | Double | Translates the ellipsoid along the x axis. |
| Y Offset | Double | Translates the ellipsoid along the y axis. |
| Z Offset | Double | Translates the ellipsoid along the z axis. |
| Ellipsoid Color | Color | The color of the variogram ellipsoid. |
| Display Variogram Lines | Boolean | Displays lines aligned with the variography ellipsoid. |
| Line Scale | Double | A scalar that sets the length of the variogram lines relative to the scale of the ellipsoid. |
| Primary Ratio Color | Color | The color of the primary ratio axis line. |
| Secondary Ratio Color | Color | The color of the secondary ratio axis line. |
| Tertiary Axis Color | Color | The color of the tertiary axis line. |
Time Settings
| Property | Type | Description |
|---|---|---|
| Chem File Is Time Domain | Boolean | Causes the file to be read as a time file, with values interpolated first to the set date and then to the grid. |
| Specify Date By Component | Boolean | Allows the Data Component value to select a date, resulting in exact data at a date instead of an interpolated value. |
| Date For Interpolation | Date | The date of interest. Used with the Date Interpolation Method to determine the value of a sample before interpolation onto the grid. |
| Analyte Name | String | The analyte name for date files. |
| Date Interpolation Method | Choice: Direct Interpolation Only, Interpolate Only, Interpolate and Extrapolate Beyond, Interpolate and Extrapolate | Defines how to interpolate when given Missing values in a file. See Interpolation Methods below for full details. |
| TCF File Name | File | The output TCF file name. When the module runs, it loops through each component and creates an EFB file; the dates and filenames are added to the TCF file. |
| Create TCF | Button | Causes the module to run in a loop, going through each component and creating an EFB file at that time. These EFB files are linked together in the specified TCF file. |
Interpolation Methods
Each interpolation method defines how to interpolate when given Missing values in a file. Non-Detect values are equal to either the Detection Limit or the Pre Clip Min. If the Date is set to the same time as a Non-Detect in the file, the sample will be a Non-Detect and not an interpolated value.
- Direct Interpolation Only: The most basic interpolation method, and the most accurate in terms of representing the data as it has been entered. Looks at the two dates surrounding the input Date. If either date, or both dates, have Missing as values, the value for that sample will be Missing and no interpolation will occur.
- Interpolate Only: Looks through the date columns both before and after the set Date for values that are not Missing, then interpolates between those numbers. If it fails to find a non-Missing value before and after the set date, it sets the data to Missing. Useful for files with a small amount of Missing values.
- Interpolate and Extrapolate Beyond: Looks through the date columns both before and after the set Date for the first instance of a value that is not Missing. If it does not find a valid non-Missing date after the input Date, it extrapolates beyond the last useable date to the input Date.
- Interpolate and Extrapolate: Looks through the date columns both before and after the set Date for the first instance of a value that is not Missing. If it fails to find one, it extrapolates the first value backwards to the input Date. If the date after the input Date is Missing, it looks forward through the time columns until it finds a date that is not Missing. It also extrapolates beyond the last valid date in the file.
Data To Export
| Property | Type | Description |
|---|---|---|
| Auxillary Kriging Data | Multi-select: Max Plume, Min Plume, Statistical Confidence, Standard Deviation, Statistical Uncertainty | Selects which kriging-derived data components to include in the output field on a node by node basis. Available when using Kriging estimation. |
| Geologic Nodal Data | Multi-select: Layer Thickness, Depth, Elevation | Selects which geologic data components to generate for the output field on a node by node basis. For structured grids, Layer Thickness is exported as cell data. |
| Geologic Cell Data | Multi-select: Material ID, Geo Layer | Selects which geologic data components to generate for the output field on a cell by cell basis. |
Display Settings
| Property | Type | Description |
|---|---|---|
| Uncertainty Spheres To Display | Multi-select | Selects which uncertainty spheres to display. There is one sphere per analyte, each reflecting the location of maximum uncertainty for that analyte. |
Drill Guide
| Property | Type | Description |
|---|---|---|
| Create DG File | Button | Runs the module in a loop, creating a synthetic boring at the maximum uncertainty location until the Number Of Synthetic Samples is reached. |
| Synthetic Sample Prefix | String | Allows the user to alter the prefix string for generated synthetic boring names. |
| Number Of Synthetic Samples | Integer | Controls how many times drill guide will run. |
| Boring Samples | Integer | Indicates how many samples to create at each synthetic boring. |
| Target Concentration | Boolean | When selected, changes the location of the uncertainty sphere based upon the specified Target Isolevel. |
| Target Isolevel | Double | When Target Concentration is selected, this value is used to change the location of the uncertainty sphere. |
| User Points | Coordinates | Manages points added to the grid for drill guide purposes to eliminate areas of high uncertainty that cannot be drilled, such as under a building. |
Processing Settings
| Property | Type | Description |
|---|---|---|
| Gpu Settings | GPU Options | GPU acceleration settings. The default for these options can be changed in the global application options menu. |