gPhone Gravimeter

gPhone Brochure
News! February 2009. gPhones measure anomalously large seismic noise, even when physically separated by over 1000 km. Click here for details.

News! July 2008. Two gPhones demonstrate high corrleation even during quiet periods. Click here for details.

News! May 2008. Six Micro-g Lacoste gPhone Gravity Meters capture the 12 May 2008 Sichuan, China Earthquake with extremely high correlation.

News! January 2007. Micro-g LaCoste gPhones capture two different Japanese earthquakes in Colorado, USA and Walferdange, Luxembourg.

Micro-g LaCoste is proud to introduce the gPhone gravity meter (previously known as the Portable Earth Tide, or "PET" meter) as the latest member of its land gravity meters. The gPhone gravity meter is based upon the LaCoste and Romberg technology that has dominated land gravity meters since 1939. The gPhone gravity meter has a low drift so that it can be used to integrate periodic signals (like earth tides) for very long time periods (years). The gPhone also has excellent high frequency response so that they can be used to monitor higher frequency non-periodic events such as earthquakes. The gPhone can be coarse-ranged over 7000milliGals (worldwide), and has a ±50 milliGal dynamic range during measurement.

The versatile gPhone gravity meter has a sophisticated data acquisition system synchronized by a rubidium clock that can be locked to GPS so that arrays of gPhones can be used to give a wider area picture of seismic or long period gravity changes due to subsurface density changes. The instrument can be monitored and controlled via the internet for remote operation.

The principle behind Micro-g LaCoste's gPhone is the patented L&R zero-length spring suspension system. The gPhone is based upon the G-Meter, but with significant upgrades: It has an improved thermal system - a double-oven - for more precise temperature stability. The instrument also has a true vacuum seal so that it is completely insensitive to buoyancy changes due to atmospheric changes. Full force feedback on the sensor allows for 0.1 microGal resolution.