Drillholes: collar, survey and 3D

Sites supply different things, so nothing about drillholes is required. Add what you have: each extra unlocks more, and a view without its data says what it is missing.

  1. Hole and depth: A hole name column and a depth column in the structure file unlock the depth strip log and the fracture frequency. Add a project column when the same hole name occurs in more than one project: files are then matched on project and hole.
  2. Survey: A survey (hole, depth, azimuth, dip) gives every structure the hole’s azimuth and dip at its depth. Alpha / beta conversion and the sampling-bias correction use it. Between stations the values are interpolated like the acQuire procedure, so results agree with a site that uses it.
  3. Collar: A collar table (hole, x east, y north, z elevation; optionally total depth, azimuth and dip) gives each structure its position and lets the holes be drawn in 3D. A hole with no survey but a collar azimuth and dip is drawn straight.
  4. Where to put them: Upload: in an Excel workbook, sheets called collar and survey are picked up on their own, or use the Drillhole files box in the Filters for separate files. Hole names must be the same in every file. The Input format page has a template with example Collar and Survey sheets.
  5. 3D drillhole traces: Charts, 3D drillhole traces: every hole from its collar along its survey (minimum curvature), the structures selected in the Filters on it. Hover for the hole, depth, type and orientation.
  6. Check the match: Under the Filters the app says how many structures found their hole, and names the holes that are in the structure file but not in the collar or survey. A mismatch in spelling is the usual cause.