| # HELP: Save - Log ASCII Standard (LAS) File, version 3.0

"The LAS standard was introduced by the Canadian Well Logging Society in 1989 to standardize the organization of digital log curve information for personal computer users. It did this very successfully and the standard became popular worldwide. Version 1.2 was the first version and followed in September 1992 by version 2.0 to address some inconsistencies. A more versatile version LAS 3.0 was released in 1999 however at present LAS 2.0 remains the dominant product. LAS 3.0 clarifies several of the poorly defined specifications of LAS 2.0 and provides expanded data storage capabilities, but has seen limited implementation.(1)"

The earlier versions of the Profile Web Application saved the collected well data into multiple XML (Extensible Markup Language) files. This was a problem in that many users wanted to share the well data, but moving the XML files up to the KGS Server and then down to the user's PC was becoming problematic. It was decided that the LAS version 3.0 would be a better method of saving / archiving the Well Information and Data. The profile program provides multiple methods for loading and plotting the well & georeport data on the same plot. The data is then saved to the LAS version 3.0 format, which allows the user to share their data more efficiently. The program uses the LAS 3.0 format to read, parse and plot the contents of the file.

For each data section, i.e. ~Core, there are 3 types, Parameters, Definitions (Curves) and Data. The "LAS File Data Types" Dialog allows the user to modify the information that will be saved to the LAS version 3.0 file. Some fields in the LAS version 3.0 are required to be filled in order for the file to be a valid LAS File. The Profile program does not enforce the rules for validation, it is just a means of saving the collected data into a format that will make it easier for the user to share data and for the Profile program to read, parse and plot the data. The user is responsible for making sure that the required fields have valid data. The program provides the required parameter type mnemonic labels. The curve mnemonics come from the data that is mapped to the KGS Standard curve mnemonics and presented in the definition type section.

To view the LAS version 3.0 Information go to the Canadian Well Logging Society - LAS -- Log ASCII Standard and select the "LAS 3.0 Information" PDF file link(1). This document outlines the new LAS 3.0 standards and data types.

There is data section "~IQ_Las_Parameter" that maps the selected Log Definitions from the "~Curve" type section to KGS Standard Tools List and to redisplay the curves when the user reloads the LAS File. It reduces the issue of having to map unknown curves to KGS Standard Curves every time the user reads the LAS File, e.g. from the STEPHENS TRUST 1 LAS 3.0 file;

Wellington KGS 1-32 LAS 3.0 Example LAS 3.0 file generated by the Profile Web Application. The DST Program added the Test (Drill Stem Test (DST)) Data Sections to the LAS 3.0 File This LAS 3.0 has the following data sections,

### Standard LAS 3.0 Data Sections

- ~Version - Version Section
- ~Well - Well Header Information Section
- ~Log - Log Data Section
  - ~Parameter
  - ~Curve
  - ~ASCII
- ~Tops - Formation Top (Stratigraphic Units) Picks Data Section
  - ~Tops_Parameter
  - ~Tops_Definition
  - ~Tops_Data | Tops_Definition
- ~Test - Drill Stem Test (DST) Data Section
  - ~Test_Parameter
  - ~Test_Definition
  - ~Test_Data | Test_Definition

### User Defined LAS 3.0 Data Sections

- IQ_Control - Recreates the Profile Plot Data Section
  - ~IQ_Control_Parameter
  - ~IQ_Control_Definition
  - ~IQ_Control_Data | IQ_Control_Definition
- ~IQ_Brine - Brine Data Section
  - ~IQ_Brine_Parameter
  - ~IQ_Brine_Definition
  - ~IQ_Brine_Data | IQ_Brine_Definition
- ~IQ_Geo_Report - Geologist Report Data Section
  - ~IQ_Geo_Report_Parameter
  - ~IQ_Geo_Report_Definition
  - ~IQ_Geo_Report_Data | IQ_Geo_Report_Definition
- ~IQ_Las_Parameter - Selected LAS Curves - KGS Profile Plot & Cross Section Web Applications. Used to assist the user in not having to map LAS File Curve Mnemonics to KGS Stanadard Tool Mnemonics.

#### Note "IQ_" proceeds every Profile Program Defined Data Section

REFERENCE:
(1) Canadian Well Logging Society, LAS - Log ASCII Standard (http://www.cwls.org/las_info.php)
LAS version 3.0: (http://www.cwls.org/docs/LAS_3_File_Structure.PDF).

Author: John R. Victorine jvictor@kgs.ku.edu