Three component geophone is one kind of geophone applied for three-component seismic prospecting. 3 C geophone can perform HVSR, MASW and vibration analysis . 

It with features of robust, light weight and convenient for field operation.

3C geophone has 3 high-precisions geophone sensors for measurements in 3 directions (X,Y,Z). Its shape has been optimized to ease the planting and improve the coupling in land environments. A leveling device is also integrated in the cap to ensure the best ground positioning.

3-C geophones string is used for multi-component seismic exploration, which has high resolution. it is widely adopted in underground water surveys, geological stratigraphy, landslide studies, pile foundation detecting, subsoil cavities detection, mining, archaeology, etc. 

We are available of triaxial geophone from 4.5Hz, 5Hz, 10Hz, 14Hz, 28Hz, 40Hz, 60Hz, 100Hz. 

Tellus-C is a high quality compact broad-band triaxial seismometer designed for easy deployment and safe transport. Tellus-C is based on Galperin configuration which allows to more easily distinguish external noise sources from internal ones and achieve higher performance.

Tellus-C can be ordered with a flat band-pass between 120s-20s and 100Hz. The lower frequency corner can be customized at the order. The transduction factor is 2000V/m/s, the output differential 40Vpp. Tellus-C is manufactured in aluminum treated against corrosion housing offering a high level of IP68K protection making it ideal for harsh environment and for field use.

Tellus-c is robust magnetic shielded and exhibits a low temperature sensitivity.

Manufactured using high quality geophones whose frequency response is extended electronically with high thermal stability and low noise components.

The transduction factor of every single unit is individually calibrated on the shake table with an accuracy within ±1%. Tellus exhibits a flat bandpass between 0.1Hz and 50Hz, opt. 100Hz. The transduction factor is 400V/m/s for the single ended version and 800V/m/s for the differential output.

Tellus 10S is manufactured in AISI316 stainless steel housing offering a high level of protection IP67 thus it is ideal for harsh environment and for field use. An aluminum hard coated housing variant is available for whom that prefer to save budget and don’t need a rugged version.

A leveling bubble and adjustable spikes are provided for an easy regulation and a quick installation, on request it is possible to have other fixing systems: a wall-mount baseplate and longer spikes.

Tellus 2S provides great results for local seismic monitoring with an excellent price-performance ratio. Tellus 2S is manufactured using high quality geophones whose frequency response is extended electronically with high thermal stability and low noise components. The transduction factor of every single unit is individually calibrated on the shake table with an accuracy within ±1%.

Tellus 2S exhibits a flat bandpass between 0.5 Hz and 100 Hz. The transduction factor of the single ended version is 400V/m/s and 800V/m/s for the differential output.

Tellus 2S is manufactured in AISI316 stainless steel housing offering a high level of protection IP67 thus it is ideal for harsh environment and for field use. An aluminum hard coated housing variant is available as a budget version when a rugged version is not needed.

LTFB-160-BH is a high-end, true mechanical force balance accelerometer, specially designed for class A seismic measurements.

Thanks to its ultra-low-noise performance and low power consumption LTFB-160-BH guarantees accurate and stable seismic measurements of both environmental noise and strong motion events.

LTFB-160 BH provides excellent long term stability,reliable measurements and is ideally suited to challenging sites where measurements can be improved by using borehole installation.

WHAT INFRASOUNDS ARE

Infrasounds are low-frequency sound waves that are below the hearing threshold (20 Hz), little perturbations of atmospheric pressure which, due to the low atmospheric absorption of these low frequencies, can propagate for thousands of kilometers and be detected by pressure sensors.

HIGH PRECISION MEASUREMENTS

HERMES is a differential infrasonic sensor based on differential pressure measurement and the use of an acoustic filter to eliminate the stationary component of atmospheric pressure. Hermes performs high precision / high reliability measurements over a wide frequency bandwidth and it’s capable of detecting low-frequency (non audible) sound waves.

INFRASONIC WAVES SOURCES

In addition to strong volcanic eruptions, there are many sources of infrasonic waves, most of which are produced by natural phenomena such as adverse weather conditions, lightning, asteroids, wave motion, outgassing and minor volcanic explosions, debris-flow, rapid mass flows such as avalanches and landslides, earthquakes and related ground shaking, sea storms, mountain waves. Artificial sources of infrasonic waves that can be measured are quarry blasting, TNT/Gas blasting during avalanche control, nuclear explosions and shock waves.

VARIOUS SENSOR TYPES

A range of sensors with different sensitivity and dynamics as well as frequency ranges are able to cover the amplitude and frequency ranges of most of these infrasound sources, allowing effective monitoring.

ROBUST AND LOW POWER CONSUMPTION

The rugged casing together with the low power consumption guarantee the employment of HERMES sensors also in hostile environment.

Tellus-L 1s is a cost-effective short band seismometer that can be used both in active and passive seismology which offers excellent price-performance ratio.

Tellus-L is manufactured with 4.5Hz geophones and offers electronically extended frequency response through an inverse-filter function. Low noise components and a compensation circuitry assure high dynamic range and stability.

The Tellus-L’s standard flat bandpass ranges from 1Hz to 100Hz, 0.2Hz to 100Hz is available on request.
The transduction factor is 120V/m/s and the output is differential.

It’s rugged design and IP68 protection make it ideal for harsh environments and for field use, moreover a metallic spike facilitates the installation in the ground.

Tellus-L comes in vertical or triaxial variant.

Tellus-R is a rotational seismometer which was conceived for measuring the rotational ground motion.

MODERN SURVEYS

Angular velocimeters are highly valued when constructing modern seismic systems which records all six components of mechanical motion.

HIGHLY PERFORMANT

Tellus-R has high sensitivity for the detection of rotational modes of earthquakes along with a wide dynamic and frequency range. A characteristic feature of the instrument is that it is low noise with a minimal power consumption, which is a significant advantage over electro-mechanical, fiber-optic and other types of rotational motion sensors. Tellus-R comes with a calibration input which allows periodic calibration without the use of expensive dedicated equipment.

ROBUST

Tellus-R comes in a hard coating anodized aluminum housing, IP67 or optionally IP68. It is well suited to harsh environments and is capable of operating at any orientation in space over a wide range of temperatures.

LTME is a high-end capacitive MEMS accelerometer which is specially designed for strong motion class B seismic measurements. Thanks to its extremely low noise, low power and wide frequency response the LTME family guarantees accurate and stable seismic measurements without the need for recalibration or maintenance during the lifecycle of the system.

LTME is available in three dynamic ranges 90, 100 and 110dB and different full-scale ranges depending on the model (±2g, ±3g, ±5g).

The broadband linear response is from DC to some hundreds of Hz (different for each version).

LTME sensitive elements are mounted orthogonally and housed in hard coating aluminum case IP67; IP68 is available optionally.

The resolution of the entry level model 90dB, meets all the requirements for strong motion event monitoring. Already in presence of light tremors, the data output is completely overlappable with mechanical force balance. The LTME response fades into noise when the ambient noise is low, whereas a true force balance can provide consistent information.

The graph below is a comparison between one of the most popular true force balance mechanical accelerometer for seismology and LTME.

During the test the two accelerometers were installed side by side in a site in the central regions of Italy where there is constant seismic activity. The event in the graph is Magnitude 3.5 while the epicenter was registered at 20Km from the installation. The unequal test provides surprisingly good results for LTME. As you can see the time traces are completely overlapped. A closer look at the spectra reveals that the spectral coherence is close to 1 in the band from 0.3Hz up to 30 Hz. This band is suitable to detect local seismic events. Moreover, the cross correlation between traces has a maximum in 0 (no phase delay). The difference in the histogram clearly shows that LTME 90 resolves vibrations well below 1mg.