Getting started

Drop a .las or .lis file onto the drop zone, click Browse file…, or use Load LAS… in the top bar once a well is already loaded (it adds another well rather than replacing the first — see Multiple wells). No file handy? Click Explore a sample well to load a synthetic well with a realistic sand/shale sequence, useful for trying out every feature below without needing real data.

LAS 2.0 files are read directly. LIS (binary) files go through a best-effort reader — see Data reliability notes before relying on absolute values from a LIS file.

Moving around the log

• Scroll or drag — pan up/down through depth.
• Ctrl+scroll or pinch (trackpad) — zoom, centered on the cursor.
• Shift+scroll, a mouse's tilt-wheel, or a two-finger side-swipe — pan sideways across tracks.
• SCALE buttons (1:200 / 1:500 / 1:1000) in the toolbar — jump to a standard log scale instead of freeform zooming.
• FROM / TO fields — type exact depths for the visible window.
• Fit button (top bar) — reset to the well's full depth range.

Tracks & curves

Curves are automatically grouped into tracks by type (Gamma Ray, Resistivity, Density–Neutron, Cement Bond, and so on); anything unrecognized gets its own track. In the Curves panel, toggle the checkbox next to a curve to show or hide it. Drag a track header left or right to reorder tracks — drop on the left or right half of a target track to choose which side it lands on.

Cement evaluation workflow

This is the core workflow the tool is built around — going from a raw amplitude curve to a defensible pass/fail call:

1. Add a cutoff. Click the ⋮ button next to a curve (e.g. your CBL amplitude) in the Curves panel. A dashed threshold line appears on its track. Drag the line to set the value; click it (without dragging) to flip which side counts as "good." The curve fills green below the cutoff and red above it (or vice-versa) in real time.
2. Calibrate a Bond Index (optional, recommended). In the Bond Index panel, pick the source curve, then mark a free pipe reference interval (uncemented casing) and a solid cement reference interval by depth or by zooming to them and clicking Use current view. Click Add Bond Index track to get a calibrated 0–1 BI curve with a default 0.8 "good bond" cutoff already applied, sitting right next to its source curve.
3. Run the Barrier Check. In the Barrier Check panel, pick the cutoff-enabled curve to check (raw amplitude or BI), set the candidate interval, and set the minimum continuous good-cement length required (defaults to 100 ft / 30 m). You get a PASS / MARGINAL / FAIL verdict, the coverage percentage, and a ranked list of every continuous good interval found — click Show on log to jump straight to it. The best interval is also highlighted directly on the depth ruler.

Zonation & depth markers

The Zonation panel has two independent tools. Zones are colored depth-interval bands (e.g. Primary/Secondary barrier) shown in their own track — click + Add zone, then edit the color, label, and top/base depth inline. Depth markers are single labeled lines spanning the full width of the plot (e.g. "Min plug setting") — add and edit them the same way. The Zonation track only appears while at least one zone exists, and drag-reorders like any other track.

QC flags

The QC Flags panel automatically scans the caliper and tension curves (if present) for two classic false positives: washouts (caliper well above the well's median, which can make amplitude read artificially high) and tool sticking (abrupt tension changes, which can put artifacts on CCL/CBL). Click a flag to jump to it. These are pattern-based heads-up flags, not a diagnosis — always confirm on the curves themselves.

Multiple wells & comparison runs

Loading a second file doesn't replace the first — a Wells panel appears at the top of the sidebar so you can switch between every well loaded this session. Each well keeps its own cutoffs, zonation, tracks, and calibrations independently.

For run-to-run QC (a repeat section, or a pressure-test rerun), use Comparison Run to load a second pass against the active well. Matching curves are drawn as a dashed overlay on the same tracks, with an optional manual depth shift to align the two. This is separate from the Wells panel — it's a transient overlay tied to whichever well is currently active, not a well of its own.

Saving & sharing your work

• Session panel — Save session downloads a small JSON file with your track order, cutoffs, zonation, annotations, and Bond Index calibration. Load session reopens one, recomputing any Bond Index curves it needs. Session files don't include the well's own curve data or a loaded comparison run — reopen the original file(s) first.
• Print button (top bar) — exports the currently visible depth range and tracks as a clean, print-ready layout with a proper header (well/field/company/date), sized to fit an A4 landscape page. Use your browser's print dialog to save as PDF.

Keyboard shortcuts

↑ ↓	Pan up/down through depth
← →	Pan across tracks
+ -	Zoom in / out
F	Fit full depth range
Ctrl+Z	Undo
Ctrl+Shift+Z	Redo

Navigation and undo/redo shortcuts are disabled while a text field has focus, so they never interfere with typing.

Data reliability notes

• LIS files are decoded by a best-effort binary reader (no official machine-readable spec was available to build against). File structure, curve names, and units are reliable; check the on-screen banner for exactly how much of the file was recovered and verify absolute values against the source acquisition software before treating them as final.
• Bond Index here is the simplified, single-receiver, linear amplitude-ratio calculation, calibrated from reference intervals you pick on the log itself. It is not the full multi-receiver, attenuation-based BI some array tools compute internally — treat it as a calibrated quick-look, and cross-check against the service company's processed BI where one is available.
• QC flags and the Barrier Check verdict are decision-support, not a substitute for engineering judgement or your local regulatory guidance on barrier verification.