Seismology

Seismology is the study of elastic waves propagation through the Earth.

Seismic methods are the most commonly conducted geophysical surveys for engineering investigations. The methods provide engineers and geologists with the most basic of geologic data through simple procedures with common equipment.

In Seismic exploration method artificial seismic energy, are created by shallow borehole explosives, artificial vibratory mechanisms or artificial highly compressed air bubbles.

The mechanical vibration initiated by the source then travels to the location where the vibration is recorded. These vibrations are seismic waves, which include compressional wave and shear wave.

There are 3 methods of exploration seismology: reflection seismology, seismic refraction and seismic tomography with reflection seismology and seismic refraction being the most common and effective.

Seismic Reflection

The seismic reflection technique maps the subsurface stratigraphy based on density and velocity contrasts between earth materials. The seismic wave, generated at the ground surface, travels through the earth and is reflected an interfaces where a change in density and velocity occurs. The reflected waves are detected by a geophone array and recorded by a seismograph.

Seismic Refraction

The refraction method uses seismic waves, introduced into the ground by a weight-drop source, to determine the compressional velocity of earth material. The seismic wave changes direction and speed, or refracted, as it propagates through the earth. When the refracted seismic wave impinges on an interface at a critical incident angle, the energy travels along the interface and sends seismic wavelets back to the surface. Geophones placed at selected intervals along the ground surface detect the ground motion and send an electrical signal, via a cable, to the seismograph. The seismograph digitizes, amplifies, filters and records the incoming signals. Analysis of the arrival times of the refracted wave provides a means for calculating the seismic velocity and modeling depths to subsurface layers.

Geospace Survey Services Limited is involved in seismology promotion and equipment sales. Geospace Survey Services has a strong strategic alliances with Hefei Guowei Electronics Company Ltd. (Hefei, China) as exclusive sales agents for HGE products in Europe and United Kingdom.

Hefei Guowei Electronics Co. are a leading technological company located in Hefei, China which formed in 2009 to engage in the research and development, production and sale of geophysical exploration instruments. Having established cooperation with many school and agencies within China, including the University of Science and Technology, Chang’an University and China University of Mining and Technology, HGE has developed and is actively growing their strong presence in academia within China.

GS101 Distributed High Precision Land Seismograph

Our GS101 Distributed High Precision Land Seismograph supports 10 thousand channel 2D and 3D seismic exploration with 32-bit high precision. Exploration depth of roughly 20m (60 feet) up to 2000m (6000 feet) depending on the source and topology structure of the project.

The instrument contains: a master station, a cross section station, an acquisition station and a PC. The system of the full system is very rugged and tough yet flexible and light for easy manoeuvrability and transportation. This highly cost effective system which one can save 15 – 25% compared to the competition. For more information on the GS101 or any other Guowei Electronics. Co. products please contact Geospace Survey Services.

Applications of GS101

Seismic applications for the GS101 High Precision Land Seismograph include: reflection, refraction, surface wave exploration, pile foundation inspection, pulse investigations, seismic imaging, vibration measurements and wave velocity. The GS101 can be has been widely used in a number of different types of studies in the realm of geological/geophysical exploration. These application studies include: oil exploration, mineral exploration, construction and engineering, ground water exploration and water conservation to name a few.