LAS File Viewer

GEMINI is a public domain web application focused on analysis and modeling of petroleum reservoirs and plays. The GEMINI project was created with a strong dependence on the Kansas Geological Surveys (KGS) Database and File Directory Structure. Most of the GEMINI Modules require digital LAS files (version 2) to run and many users have voiced a displeasure of having to upload their files to KGS first in order to run GEMINI.

LAS Viewer Applet was created to assist the user in locating and viewing digital LAS (Log ASCII Standard version 2.0) Files. This web site will allow the user to open and plot a digital LAS File on the Users PC, without having to upload the file to KGS first or buy an expensive software package.

This new version adds a number of new features. The older version restricted the number of plot tracks that could be displayed at any one time. This version automatically reads and parses the digital LAS file and groups the log curves into standard KGS log curve types, i.e. Neutron Porosity, Bulk Density, etc. The program then determines the type of log, i.e. Neutron/Density Log and automatically displays a number of standard plot tracks. Although the program displays a set number of standard plot tracks, the program also has a control dialog that allows the user to turn plot tracks on or off and even change the order of the plot tracks. The user can save that image as a Portable Network Graphics (PNG) image file.

This dialog automatically determines the type of log that is being displayed by the type of LAS File log curves. The program searchs the log curves in the LAS file to determine the log type, by default if the LAS File has Neutron Porosity and a Bulk Density or Density Porosity then it will be display no matter what other log curves are available. The Plot Track Control dialog will allow the user to turn on the other plot tracks. There are 5 types of default presentations in the order of selection,

  1. Neutron/Density Log: The LAS File contains a Neutron Porosity, Bulk Density (Density Porosity) with or without Photoelectric Factor.
  2. Resistivty Log: The LAS File contains Resistivity Curves, there are 5 types of presentation, Induction, Micro Resistivity, Laterlog, Array Resistivity and other.
  3. Sonic Log: The LAS File contains Sonic Log Curves
  4. Spectral Gamma Ray Log: The LAS File contains Uranium, Thorium and Potassium Log Curves
  5. Gamma Ray Log: The LAS File has only a Gamma Ray Log.

To save the oil & gas data to your pc this web application uses an io class that will create and maintain a KGS Application XML File Database on your pc. The web application requires that the user give permission to read & save oil & gas data on their pc each time they execute this program.

NOTE: This web application will not move data from your pc to the KGS Server without your permission. There is an "Upload your Kansas digital LAS Files" button and this is the only application that will move data to the KGS Server from your pc. The user has to enter the directory path & filename in order for the web application to work.

Generally the web browser only allows the user to access of files that are on the Server that the web application resides on. This Web Application uses a JAR Signing and Verification Tool to protect the Web Application from being modified by anyone else except the developer of the application. This tool provides the capability to verify the signatures and integrity of the Web Application. The Web Application cannot be forged, the verification process is also a function of the data that was originally created with the original signing process and can not be altered. If the data has been changed the verification signature will no longer verify as being authentic.

A directory IQSTRAT_DATA will be created under your home directory on your PC. A IQSTRAT_DATA.xml file will also be created under your home directory telling the web application each time you enter were this directory structure is. This way you do not have to remember were your data is, the web application will do that. The io class builds "Projects" automatically when a user first saves data to the XML File Database and maintains the project integrity by creating unique directory names from the date and time. For the LAS Viewer web application the projects will begin with a "P" to represent Profile Plot application. There are other web applications that will also use this XML File Database structure and will use other prefixes to distinguish them from the well level projects.

This program has three options for finding and displaying well data in a well profile plot,

  1. New Well Profile: This version allows the user to combine multiple data sources into one plot, Once the user loads and plots the well profile data and sets the plot tracks and depth ranges in the format they wish they can save that data for future reference.
  2. Previously Saved Well Profile: This version allows the user to display a previously saved well profile session.
  3. KGS Data Well Profile: This version allows the user to search the KGS database for wells and launches the KGS LAS Viewer. The KGS LAS Viewer has other capabilities that this version does not since the presentation of the data is presented with KGS in mind.

Developing software takes time and effort. If you like our web tools and would like to help support future versions, please consider making a donation! Donations of all sizes are appreciated.

We accept checks payable to the Kansas Geological Survey (KGS). Checks must be in US$ and drawn on a U.S. bank.

Kansas Geological Survey
1930 Constant Ave.
Lawrence, KS
66047-3726 USA
To assist administration please add "LAS File Viewer" in the "For" section of the check.
You may contact us
by e-mail at
by phone 785-864-2100
by fax 785-864-5317

Author: John R. Victorine

This page created September 2004, modified July 2009. Send comments to
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