What is a Betsy Gun?
Named after Davey Crockett's rifle, the term Betsy Gun covers a broad range of seismic sources that ignite gun powder to transmit acoustic energy down into the Earth. Several different types of Betsy Guns exist, with a broad range of applications. We produce and offer support for all of types of Betsy Guns.
A Low-Impact Seismic Source
The Betsy Gun BFG-1000 series uses a 4 inch diameter 2 foot deep
hole and a minimal surface area (4 sq. ft) for operation. The low impact at the surface makes it perfect for working in highly sensitive environments. Our blank ammunition contains a sulfur free propellant and does not fire projectiles, ensuring near-zero environmental impact.
Superior Data Quality
Betsy Guns produce both P and Sv Waves from a single shot. P waves penetrate to over 1km with a dominant frequency of 80Hz while Sv waves provide ~5m resolution in the top 200m with no need for three component sensors. Betsy Guns produce the sharpest wavelet of any land seismic source, and clean low frequency surface waves ideal for MASW or ReMi or DAS applications with coherent energy down to 2Hz.
The Cutting Edge of Seismic Technology
Betsy Guns have played an important role in the development of DAS technology Martin et al., 2017, and are considered the premier active source for DAS array studies, high-resolution shallow subsurface work, and seismic investigations of glacial mechanics.
What sets the Betsy Gun apart from other sources?
Safety
The Betsy Gun has been completely redesigned with user safety as the highest priority. Users stand at a safe distance while the Betsy Gun is fired, significantly reducing the risk of injury during field operations compared to legacy systems. Our Betsy Guns are safer to use than a sledgehammer.
Data Quality
Betsy Guns excite the broadest spectrum of waves for any impulsive land source that doesn't require an explosives license, making them the best source for seismic in the shallow subsurface.
Betsy Guns use propellants that burn faster than a weight drop can transmit energy to the ground producing a broader-band and higher energy seismic wavelet.
Betsy Guns both P and Sv waves (drilled shot holes generate tube waves that produce Sv) allowing estimation of compressional and shear velocities from a single seismic record. This means that a single Betsy Gun shot provides Vp/Vs information, a unique property of explosive sources.
Rayleigh waves produced by this source allow for the best possible surface-wave analysis and site hazard classification. The low frequencies produced in a Betsy Gun shot simply cannot be produced by stacking sledgehammer blows.
Ammo is available up to 117 kJ per shell and can image down to 1 km in most situations.
Accessibility
Betsy Guns are affordable, durable, and easy to maintain. Betsy Guns and their ammunition are not considered firearms by BATFE, and have no special licensing or permitting requirements. Comparable sources like electro-mechanical vibrators, start at $40,000 for a tiny unit. Weight drops and sledgehammers suck. Explosives require expensive permitting and licensing and are simply not possible to use in urban/suburban settings. Vibroseis trucks require cutting vegetation.
Versatility
The BFG-1000 can be used in multiple configurations to maximize versatility and to allow access to remote field locations. When access permits, use the blast shield and sandbags for maximum data quality. For remote locations with no vehicle access, our allows for high quality seismic sources with a minimum of carry-in weight.
