@geoharkat/dlis-parser

Parse RP66 V1 (DLIS) well-log binary files — in the browser and Node.js with zero runtime dependencies.

Features

• Full RP66 V1 / DLIS binary parsing (Storage Unit Label, Visible Records, Logical Record Segments)
• Correct EFLR parsing: CHANNEL, FRAME, ORIGIN, PARAMETER, ZONE, EQUIPMENT, TOOL, CALIBRATION families
• FDATA IFLR decoding with proper per-frame UVARI frame-number handling
• All 25 RP66 V1 representation codes (including IBM float, VAX float, FSHORT, complex)
• Multi-dimensional and waveform array channels
• Export to CSV and LAS 2.0
• Vendor quirks: Baker Hughes ATLAS ABSATR extension, Schlumberger VR version byte variants
• Works in browser (fromBuffer) and Node.js (fromFile)
• Full TypeScript type declarations included

Install

npm install @geoharkat/dlis-parser

Quick start

Node.js

import { DLISFile } from '@geoharkat/dlis-parser';

const file = await DLISFile.fromFile('well.dlis');

// Well metadata
const origin = file.origin;
console.log('Well:', origin.wellName, '|', 'Field:', origin.fieldName);
console.log('Company:', origin.company);

// List frames and channels
for (const frame of file.frames.values()) {
  console.log(`Frame "${frame.name}"  index: ${frame.indexType}  channels: ${frame.channelNames.join(', ')}`);
}

// Decode a frame
const frame = file.logicalFiles[0].getFrame('MAIN');
const { frameCount, data, channels } = frame.decode();

console.log(`${frameCount} depth samples`);
console.log('DEPTH[0]:', data.DEPTH[0], channels.find(c => c.name === 'DEPTH').units);
console.log('GR[0]:',    data.GR[0]);

// Export
const csv = frame.toCSV();
const las = frame.toLAS();

Browser

<input type="file" id="fileInput" accept=".dlis">
<script type="module">
import { DLISFile } from 'https://cdn.jsdelivr.net/npm/@geoharkat/dlis-parser/src/index.js';

document.getElementById('fileInput').addEventListener('change', async e => {
  const buf = await e.target.files[0].arrayBuffer();
  const file = DLISFile.fromBuffer(buf);

  for (const frame of file.frames.values()) {
    const result = frame.decode();
    if (result) console.log(frame.name, result.frameCount, 'frames');
  }
});
</script>

API

DLISFile

| Member | Description | |--------|-------------| | DLISFile.fromBuffer(buffer: ArrayBuffer) | Parse from an in-memory buffer (sync) | | DLISFile.fromFile(path: string) | Parse from a file path (async, Node.js only) | | .sul | Storage Unit Label ({ version, structure, maxRecordLength, storageSetId, … }) | | .logicalFiles | Array of LogicalFile | | .origin | Shortcut → logicalFiles[0].origin | | .frames | Shortcut → logicalFiles[0].frames | | .channels | Shortcut → logicalFiles[0].channels | | .warnings | Non-fatal parse warnings (string[]) |

LogicalFile

| Member | Description | |--------|-------------| | .id | File ID string (from FILE-HEADER) | | .origin | Well/acquisition metadata (OriginInfo) | | .channels | Map<key, ChannelInfo> keyed by 'origin/copy/name' | | .frames | Map<key, Frame> keyed by 'origin/copy/name' | | .parameters | ParameterInfo[] (KB, TD, BHT, mud weight, …) | | .getFrame(name) | Find Frame by name (case-insensitive) | | .getChannel(name) | Find ChannelInfo by name (case-insensitive) |

Frame

| Member | Description | |--------|-------------| | .name | Frame name string | | .indexType | e.g. 'BOREHOLE-DEPTH', 'TIME' | | .direction | 'INCREASING' or 'DECREASING' | | .spacing | Nominal depth/time step (number or null) | | .channelNames | string[] in recording order | | .channels | ChannelInfo[] fully resolved | | .decode() | Returns DecodeResult | | .toCSV(opts?) | Export scalar channels to CSV string | | .toLAS(opts?) | Export scalar channels to LAS 2.0 string |

DecodeResult

{
  frameCount:   number;
  frameNumbers: Int32Array;          // RP66 frame numbers (1-based)
  channels:     { name, longName, units, repcode, dimension }[];
  data:         { [channelName]: Float64Array };  // length = frameCount * stride
  strides:      { [channelName]: number };        // 1 for scalars, N for array channels
}

Reading array channels:

// DTCO_WAVE has dimension [512] → stride = 512
const wave0 = result.data.DTCO_WAVE.slice(0, 512); // waveform at first depth
const wave1 = result.data.DTCO_WAVE.slice(512, 1024);

Representation codes

import { RC } from '@geoharkat/dlis-parser';

// RC.FSINGL = 2  (IEEE 754 single)
// RC.FDOUBL = 7  (IEEE 754 double)
// RC.IDENT  = 17 (short ASCII string)
// etc.

Null values

DLIS has no universal null. Common vendor nulls are detected by isNullVal() inside the library but all values are returned as-is so you can apply your own masking:

import { NULL_VALUES } from '@geoharkat/dlis-parser';

const masked = Array.from(result.data.GR).map(v =>
  !Number.isFinite(v) || NULL_VALUES.has(v) ? NaN : v
);

Contact

Ismail Harkat — [email protected]

Issues: https://github.com/geoharkat/dlis-parser/issues

License

MIT © 2025 Ismail Harkat