New & Noteworthy

Fact Sheet: Water Quality Studied in Areas of Unconventional Oil and Gas Development, Including Areas Where Hydraulic Fracturing Techniques are Used

  Video: Shale Gas, Hydraulic Fracturing, and Induced Earthquakes

  USGS Groundwater Data Go to Times Square

  TWRI-B3 Chapter 2: Introduction to Ground-Water Hydaulics [12MB PDF], now with internal document links added

  Groundwater-Level Response to Virginia 2011 Earthquake

  Groundwater Technical Procedures of the USGS

USGS Groundwater Watch

USGS maintains a network of active wells to provide basic statistics about groundwater levels.

USGS in Your State

USGS Water Science Centers are located in each state.

Other USGS Water Science Areas

 Water Resources

 Water Quality

 Water Use

 Surface Water

FLASH: A Computer Program for Flow-Log Analysis of Single Holes

Overview

FLASH (Flow-Log Analysis of Single Holes) is a computer program for the analysis of borehole vertical flow logs. The code is based on an analytical solution for steady-state multi-layer radial flow to a borehole. The code includes options for (1) discrete fractures and (2) multi-layer aquifers. Given vertical flow profiles collected under both ambient and stressed (pumping or injection) conditions, the user can estimate fracture (or layer) transmissivities and far-field hydraulic heads. FLASH is coded in Microsoft Excel with Visual Basic for Applications routines. The code supports manual and automated model calibration.

Release History

First official release is version 1.0, released March 7, 2011. FLASH v1.0 has been tested for use with Microsoft Excel 2007 with Visual Basic for Applications routines

Source Code and Documentation

• FLASH v1.0 [450KB XLSM]
• Documentation [800KB PDF]
• Installation and troubleshooting README file [160KB PDF]

Point of Contact

Support is provided for correcting bugs and clarification of how FLASH is intended to work. Only limited assistance can be provided for applying FLASH to specific problems by contacting the point of contact listed below:

Fred Day-Lewis
U.S. Geological Survey
Office of Groundwater, Branch of Geophysics
11 Sherman Place, Unit 5015
University of Connecticut
Storrs Mansfield, CT 06269
(860)487-7402 x21

Other USGS Groundwater Software

The USGS develops groundwater, water-quality, surface-water, and other water-resources software for use by the USGS in fulfilling its mission. Most of this software is available online for download at no charge.

Disclaimers and Notices

Please refer to the USGS Software User Rights Notice for complete use, copyright, and distribution information. The USGS provides no warranty, expressed or implied, as to the correctness of the furnished software or the suitability for any purpose. The software has been tested, but as with any complex software, there could be undetected errors. Users who find errors are requested to report them to the USGS.

References to non-USGS products, trade names, and (or) services are provided for information purposes only and do not constitute endorsement or warranty, express or implied, by the USGS, U.S. Department of Interior, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.

Note: Some or all of this information is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of the free Adobe Reader from the Adobe web site.  Visit http://www.adobe.com/accessibility/  for free tools that allow visually impaired users to read PDF files.