See what is inside a DLIS file
A DLIS file is a binary container: one file can hold several logical files (often one per run or per processing step), each with several frames sampled at different steps, plus hundreds of parameters, tool descriptions and remarks. A text editor shows nothing useful, and the programs that open it (Techlog, Geolog, Petrel, the logging company's own viewers) need a licence or an account.
Upload the .dlis file and you get, without installing anything:
- a PDF log print of every frame with gamma ray, caliper and SP in the first track, resistivity on a logarithmic scale, density, neutron and sonic in the third, further curves in extra tracks, and borehole images drawn as an image track;
- a header file with the origin (well, field, company, service company, product and date), every channel with its units and long name, every parameter with its value, the tools and the comments;
- every frame as LAS 2.0, CSV and an Excel sheet, ready for a petrophysics program or a spreadsheet.
The table on the result page lists the frames: their index (depth or time), range, step, number of samples and number of curves, so you can see at once which frame holds the main logs and which are station logs or repeat passes.
Depth or time
Most frames are indexed by depth. Formation testers, coring tools and station logs often write frames indexed by time instead, with the depth as an ordinary channel. Those frames are kept in time order: their LAS files start and stop in milliseconds and carry the depth channel next to the others.
Pitfalls
- Depths stored in tenths of an inch look like huge numbers in raw dumps (295080 for 2459 ft). The converter turns them into feet or metres; choose the unit under "Depth unit".
- Some frames are encrypted by the logging company. They hold proprietary tool data and are listed as skipped; the logs themselves are normally in other frames.
- Image logs carry 16, 56 or more values per depth. They are drawn as pictures and, unless you switch it off, written as one column per sector.
More about what this tool reads and writes: Well Log Converter (DLIS, LIS, LAS).