Map building
Map building builds a map from a horizon, from well markers or from a point set in a single dialog, with its own set of parameters. Open it on the Modelling ribbon tab, in the Mapping group, by clicking Map building.
The dialog stays open while you work, so you can build a map, look at the result and build the next one without reopening it. The parameters are kept with the project. The General tab holds the input data and the main build parameters, and the Advanced tab holds the settings of the selected algorithm.
Input data
Input type sets the kind of data the map is built from. The controls beneath it change with the selection:
- Horizon — select one of the project horizons in the Horizon list.
- Well markers — select a marker of the active marker set in the Marker list, then the value to map in Attribute. The attribute list offers MD, TVD, TVDSS and the attributes of the marker itself; TVDSS is used by default.
- Points — select a point set in Point set and one of its numeric columns in Attribute.
Map name is the name of the resulting map. It follows the selected input object until you type a name of your own, and it must not be empty when the map is built.
Build parameters
- Algorithm — ABOS, Kriging or Adaptive Snap. The Advanced tab always shows the settings of the algorithm selected here.
- Step X and Step Y — the cell size of the resulting map, 25 m by default. These boxes, and every other distance in the dialog, are labelled and entered in the distance unit of the project, so an imperial project shows the same default in feet.
- Map box — the area the map covers: Input points (the extent of the input data), All bins (the whole survey, which requires a defined survey bounding box) or Polygon, which adds a Polygon list for choosing the outline.
Fault handling
Select in Fault handling how faults constrain the map:
- Ignore faults — faults are not used and the map is continuous across them. The remaining fault controls are hidden.
- Use selected faults — click Select faults… and tick the faults to be used as barriers. The label beside the button shows how many faults are ticked, or All when nothing is ticked and every fault of the project is used.
- Use fault model — use the surfaces of the model selected in Fault model as the barrier framework.
- Fault polygon — use the outlines of the polygon selected in Fault polygon as the barriers.
With every option except Ignore faults the Faults clear radius box appears. Input data lying closer to a barrier than this distance is discarded and that strip is rebuilt from the reliable data further away, which removes noisy values along the fault without leaving the strip empty.
Smoothing and trend
Post-mapping smoothing smooths the finished map, and Step sets the width of the smoothing window. The option is cleared by default.
Use trend builds the map on top of a regional surface: the map selected in Trend map is subtracted from the input data, the difference is interpolated and the trend is added back. The trend map must hold the same kind of values as the input data, so a depth input needs a depth trend map. Input points that the trend map does not cover are not used, and their number is reported when the map is built. The option is cleared by default.
Advanced
The Advanced tab shows the settings of the algorithm selected on the General tab:
- ABOS — Use nearest, Max error, Number of iterations, Factor, Taper size, Smooth aperture, Smoothing iterations and Smoothing Q.
- Kriging — Covariance (Spherical, Gaussian or Exponential), Range and Max points.
- Adaptive Snap — Fault mode (Ignore, Barrier or Final refinement only) and Density (Auto, Sparse (wells) or Dense (grid)).
Building the map
- Run — builds the map and leaves the dialog open.
- OK — builds the map and closes the dialog. With no input object selected it only stores the parameters and closes.
- Close — closes the dialog without building a map.
The result is saved in the Calculated maps folder of the Data Manager. If a map of the same name is already there, you are asked whether to overwrite it.
See Also