Horizons Wizard

The horizons wizard allows the user to set the options used to create Solids, a 3D Mesh or HUF data from borehole and TIN data. This command can be found by selected the TIN

Page 1 - Horizon Elevations

The first page of the wizard allows the user to select the Horizon elevation inputs. The Page is broken up into three sections with their options described below:

• Boreholes

  Boreholes can be selected as input for the horizon approach be selecting the Use Boreholes toggle.

  Select borehole folder

  A subset of boreholes can be used instead of all of the boreholes in memory by switching to the Select borehole folder option and selecting a borehole folder from the tree control.

  Use borehole cross section data

  Turning this toggle on means that all user-defined borehole cross sections will be used in creating the solids or HUF data. Click here to learn more.

  Represent missing horizons implicitly

  Many times it is desirable to have certain horizons pinch out or stop.  This is can be accomplished by selecting the Represent missing horizons implicitly toggle. Click here to learn more.  

  Consider the boreholes shown in the figure below.
  
  
  Sample boreholes with missing horizons.
  
  Notice that on borehole 3G that horizons 1 and 2 are missing.  On hole 8G horizon 4 is missing.
  
  
  Cross Section between holes 3G and 8G
  
  The figure above is a cross section through the solids between holes 3G and 8G.  Notice the layer that is associated with horizon 4.  This layer passes through hole 8G even though the horizon is not present on hole 8G. With the Represent missing horizons implicitly option turned off, hole 8G would be ignored when interpolating horizon 4, and hole 3G would be ignored when interpolating horizons 1 and 2.
  
  
  Placement of Missing Horizons.
  
  However, with the toggle turned on, the missing horizons would be placed as shown in the figure above.  
  
  
  Cross Section between Boreholes 3G and 8G.
  
  The figure above is a cross section between through solids created with the Represent missing horizons implicitly option turned on. Notice that the layers associated with horizon 4 and 2 pinch out.

   

• TINs

  TINs can be selected as input for the horizon approach be selecting the Use horizon TINs toggle.

  Select TIN folder

  A subset of TINs can be used instead of all of the TINs in memory by switching to the Select TIN folder option and selecting a TIN folder from the tree control.

   

• Conceptual model

  Horizon Conceptual Models can be selected as input for the horizon approach be selecting the Use horizon conceptual model toggle. Which conceptual model to be used is then selected from the tree control. Click here to learn more.

   

Page 2 - Top and Bottom Elevations

The second page of the wizard allows the user to select the primary tin, the primary coverage, adjust the grid elevations, and set the top and bottom elevations. The options on this page are described below:

• Primary TIN

  This option is available when using the Horizons -> Solid command. The primary TIN is selected in the tree window, and it defines the boundary of the solid. Also, the density of the triangles in the primary TIN controls the density of the triangles in the solids that are created.

• Primary 2D Mesh

  This option is available when using the Horizons -> 3D mesh command. The primary 2D Mesh is either selected form memory or a coverage is selected from the tree window the meshing coverage is used to create a 2D mesh. the 2D Mesh defines the boundary of the 3D Mesh and the projection of the 3D elements.

   Also, the meshing options assigned to coverage controls the meshing of the 3D Mesh that is created. Only the coverages that are within either a FEMWATER or SEEP2D coverages can be used as the primary meshing coverage.

• Adjust Grid Elevations

  This button is available when using the Horizons -> HUF command.  The button opens a dialog that allows the user to adjust the 3D grid elevations. Click here to learn more about this option.

   

• Top elevation

  This section of the dialog allows the user to specify how the top elevation of the solids, 3D Mesh, or HUF data will be determined.  The user can select to use the top of the boreholes, a separate TIN, or a constant elevation.

• Bottom elevation

  This section of the dialog allows the user to specify how the bottom elevation of the solids, 3D Mesh, or HUF data will be determined.  The user can select to use the bottom of the boreholes, a separate TIN, or a constant elevation.

Page 3 - Interpolation and Build Options

The third page of the wizard allows the user to select the interpolation options and some specific options for the Solids and 3D Mesh generation.

• Nodal function

  The nodal function corresponds to the interpolation method that is selected. The available nodal functions are constant, gradient plane, and quadratic. The nodal function option is only available if the user is not including cross section data.

• Solid Options

  These options are available when using the Horizons -> Solids command.

  Intersect Horizon surfaces.

  This option will add the horizon intersections to the primary TIN.

  Minimum element thickness

  This option constrains the solid generation process to only create solids with a minimum thickness of the provided value.

  Put Solids in New Folder

  This options puts the generated solids into a folder in the Project with the specified name.  

• Meshing Options

  These options are available when using the Horizons -> 3D Mesh command.

  Minimum element thickness

  This option constrains the mesh generation process to only create elements with a minimum thickness of the provided value.

  Layers distributed by depth

  This option constrains the mesh generation process to only not create elements of the specified materials types thicker than the specified values.

  Refine Elements

  This option will refine all of the elements in the resulting 3D mesh or just the layers in which pyramid elements are created. Most numeric models do not support pyramid elements thus the refine layers with pyramids will refine only the layers needed to limit the number of elements needed to represent the stratigraphy without pyramids. All refined elements are transformed into tetrahedrals.