Logging: Logs in the 3D View and Boreholes
A log stands on the outcrop as a graphic panel in the 3D view; this page covers how it looks there, and logging boreholes. Digitising a log and editing its beds is in Geological Logging.
The log in the 3D view
In the Vulkan view each log stands on the outcrop as a graphic log panel: its 2D grain-size track, drawn by the same code as the 2D log panel. The panel's left edge is the logged line, so each bed stays against the rock it was logged on, and grain size grows to the right as it does on paper. A bed shows its profile, its fill in the Secondary Display colour, its facies pattern, its structure and fossil symbols, its base contact, the crossed box of a covered bed and the ? of a queried contact. The OpenGL view draws the older prism columns.
The options are rows in the display properties of the Logs group, shown when you select the Logs branch of the Data tree, and they apply to every log in the project. The full list is on the Logs tree page.
Column Style and Log Style
Column Style is Panel by default. Prism keeps the older column, a 10-sided prism round the logged line as wide as each bed's grain size. Only the prism reads Primary Display; a panel is always as wide as the grain sizes. Log Units hides the beds in either style, and Track Unit Width is the width in metres that the coarsest grain size reaches (0.5 m by default).
Log Style sets where the panel stands and which thickness it draws:
| Log Style | The panel stands | Thickness |
|---|---|---|
| Deviated | Along the logged path, each bed from its base to its top. | MT |
| TVT | Upright at each bed's base. | TVT |
| TST | In one upright column at the log's base, the beds stacked in order. | TST |
| Vertical, Vertical 2D | Upright above the log's base, each bed at its own height. | TVT |
Preview TST draws every log as TST, whatever its Log Style.
Keeping the panel readable
The logged line lies on the rock, so a panel standing on it would be cut by the outcrop. Panel Lift draws each panel towards you along your line of sight, in metres. It stays over its beds on screen, but rock within that distance in front of it no longer hides it. A ridge further in front of the log still does. 0 uses one Track Unit Width.
Panel Backing is the opacity of a white sheet behind the panel, from 0 (none) to 1. It starts at 0.5, which keeps black lines and patterns legible over dark rock. Panel Opacity fades the whole panel, from 1 (solid) towards 0, to see the outcrop through it.
Which way it faces
Panel Facing is Camera by default: each panel turns about its line to face you, with the grain sizes always growing to the right. Outcrop lays the panel along the rock instead, using the average normal of the triangles the log's path is anchored to, so it stays still as you orbit. That suits a figure or a VR visit. The anchors come with Keep Interpretations On Their Models. A log with none, such as an imported column or one logged on a point cloud, has no rock to lie on and keeps facing the camera.
What it shows
Each of these is a row of its own:
| Row | Default | What it draws |
|---|---|---|
| Panel Patterns | On | Each bed's facies pattern. |
| Panel Symbols | On | Each bed's structure and fossil symbols, with abundance letters. |
| Panel Depth Ruler | On | A ruler left of the line: a tick every metre, a long tick every 5 m. The major ticks are labelled in metres from the log's base, thinned to stay at least 40 pixels apart on screen. |
| Panel Grain-size Grid | On | Faint lines up the panel at the grain-size classes. |
| Panel Palaeocurrents | On | An arrow right of the panel at each bed's middle, one per reading, pointing in its true azimuth. |
| Panel Bed Dips | Off | A dip disc beyond the arrows, for each bed whose dip or azimuth is not 0. A bed at 0 towards 0 counts as not measured. |
| Panel Log Name | On | The log's name over the top of its panel. |
| Panel Interval Names | Off | Each of the log's intervals named at its top, right of the panel, in the interval's colour. |
| Panel Contact Ticks | Off | A line across the outcrop at each bed's base, left of the ruler, three Track Unit Widths long. It runs along the bed's strike where its dip was measured, and level otherwise. It shows which ledge is which bed. |
Panel Extra Track adds a second 2D track right of the grain sizes, a little over a quarter of the track wide: None (the default), Facies, Facies Association or Intervals. The panel widens to take it, and the arrows, discs and interval names move out past it.
At a distance
A panel narrower than 8 pixels on screen, or seen nearly edge-on, draws as a colour stripe instead: the log's line, 5 pixels wide at any distance, each bed in its colour. So logs still read as their beds across a whole outcrop. A panel's picture follows the camera as well, sharpening a moment after you move in.
Clicking on a panel
A click tests the panel, not the logged line. On the active log it selects the bed under the cursor, and Ctrl+click and Shift+click add to the selection as in the 2D log. The empty part of the track right of a thin bed's profile takes no click, though a bed always has at least a tenth of the track's width to click on. Anywhere on the extra track picks its bed. A double-click opens the log in its 2D log panel.
In VR
A headset draws the panels the desktop view has made, each turned to face the head and lifted towards it. A log the desktop view shows only as a colour stripe has no panel to send. See the VR guide.
Boreholes
Interpretations → Sedimentology → Borehole creates a borehole rather than an outcrop section — a log with a deviation path defined in space rather than digitised on a mesh. Wireline data comes in through the LAS import.
Core
A cored well keeps a record of the core itself beside its description: the runs cut, the boxes the core is laid in, and how core depths line up with the wireline logs. Right-click a log in the 2D log view (a bed or the log's header) and open Core:
| Command | What it reads |
|---|---|
| Import Core Runs (CSV)... | One row a run: run (or name), top (or from), base (or to), and the core recovered in metres or the recovery (or TCR) in percent of the run. |
| Import Core Boxes (CSV)... | One row a box: box (or name), top, base. |
| Import Depth Shift (CSV)... | Ties of core depth to log depth: core (or driller), log (or logger). |
| Import Core Box Photo... | A photograph of a core box, cut into its rows and laid along the log. |
| Clear Core Data | Takes the runs, boxes and depth shift off the log. |
Columns are found by name, in any order and any case. Depths are measured depths down the hole in metres from the kelly bushing, as the log's LAS curves are, so the log needs a path; see Geotechnical Borehole Data. Importing again replaces what was there. The messages panel lists rows that were left out and why. The core is saved with the log.
The Core track
Add a Core track to the template. Each run is drawn as a box from its top to its base across the left of the track. The core recovered fills it from the run's top down, what was lost is crossed out, and the recovery is written beside it. The boxes are outlined and named on the right of the track. The SVG export and the printout draw the track as the screen does.
Depth shift
Core is measured in the driller's depths, which rarely match the logger's. The depth shift ties core depths to log depths, matched on the wireline logs:
- One tie shifts everything by the same amount.
- Two or more stretch the core between them.
- Beyond the first and the last tie, their shifts hold.
The runs, the boxes and the photographs are drawn at their shifted depths. Import the depth shift before the photographs: a photograph is placed when it is imported.
Core box photographs
Import Core Box Photo... asks for:
- the photograph;
- the core depths at the top and the base of the box (filled in when the photograph's name holds the name of one of the log's core boxes);
- how many rows of core the box holds;
- how much to trim off each side of the photograph, in percent, so that what is left is the rows themselves;
- which end of each row is the top of the core: the left, as boxes are usually laid, or the right.
The rows share the box's depths equally, the first row the shallowest. Each row is cut out, turned to run down the log, and put on the log's Image track at its shifted depths. A row that falls off the log is left out. Drag a row's top or base on the Image track to fit it, as for any image put on a log.