USGS Groundwater Information
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FLASH: A Computer Program for Flow-Log Analysis of Single Holes
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.
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
Day-Lewis, F.D., Johnson, C. D., Paillet, F.L., and Halford, K.J, 2011, FLASH: A Computer Program for Flow-Log Analysis of Single Holes v1.0: U.S. Geological Survey Software Release, 07 March 2011, http://dx.doi.org/10.5066/F7319SZC.
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:
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
This software has been approved for release by the U.S. Geological Survey (USGS). Although the software has been subjected to rigorous review, the USGS reserves the right to update the software as needed pursuant to further analysis and review. No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. Furthermore, the software is released on condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from its authorized or unauthorized use. Also refer to the USGS Water Resources Software User Rights Notice for complete use, copyright, and distribution information.
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Software License and Purchase Information
This software is a product of the U.S. Geological Survey, which is part of the U.S. Government.
This software is freely distributed. There is no fee to download and (or) use this software.
Users do not need a license or permission from the USGS to use this software. Users can download and install as many copies of the software as they need.
As a work of the United States Government, this USGS product is in the public domain within the United States. You can copy, modify, distribute, and perform the work, even for commercial purposes, all without asking permission. Additionally, USGS waives copyright and related rights in the work worldwide through CC0 1.0 Universal Public Domain Dedication (https://creativecommons.org/publicdomain/zero/1.0/ ).
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