- provides 2 to 3 days lead time before any major earthquake
- combines information available from satellites, both on geostationary and low-Earth orbits, with information available from regional ground station
networks and other ground assets
- monitors the range of signals that the Earth produces when stresses build up deep below to dangerously high levels, heralding an increased probability of a major seismic event
- never again a major earthquake will strike “out of the blue”
- occasional false positives have to be accepted

Main Elements

❖ Satellite-derived information on thermal infrared (TIR) emission from the ground, on ionospheric perturbations to be separated from geomagnetic storm effects.
❖ Regional ground sensor network has to extend over an area of at least 500 km radius, encompassing Romania, Bulgaria, Macedonia, Serbia,
Greece, and Turkey.
❖ Data platform for data analysis, evaluation and forecasting.
❖ Web-Mobile Apps for alerts communication

Monitoring Seismo-electric Potentials and Conductivity Changes

Electrical Ground Potential and Conductivity Changes due to Stresses in Earth’s Crust

This invention relates to applications that derive from the discovery that positive holes become activated during periods of increasing tectonic stresses in and around the focal volumes of future earthquakes deep in the Earth’s crust.  These electronic charge carriers spread out from the stressed rocks into the surrounding less stressed or unstressed rocks, traveling fast (initially up to 100 m/s) and far (up to tens of kilometers), able to reach the Earth surface. As the positive holes spread through the rocks and through the soil, they temporarily increase the number density of charge carriers in these media and thereby affect their electrical conductivity. This invention relates to monitoring the ensuing changes in electrical conductivity of the soil and rocks deeper underground, allowing to derive information about the spreading of the electronic charge carriers as a function of space and time.

The Earth surface represent a boundary where the effective dielectric constant at lim. 0 Hz changes abruptly from relatively high values, ranging from about 10 to nearly 100, to about 1, the dielectric constant of air. As a result, the positive holes become trapped at the ground-to-air interface forming a relatively thin surface charge layer, which becomes thinner as the number density of mobile charge carriers in the underground increases. The surface charge layers are associated with an electric field, which increases exponentially with increasing number density of charge carriers arriving at the surface. Due to the mutual electrostatic repulsion between the positive hole charge carriers, they accumulate more on topographic highs than in valleys and on flat land. In addition, electrical potential differences develop between the ground-to-air interface and all points below the surface at different depths.

We propose to measure the potential differences (in Volts) between different depth layers using (1) contact electrodes inserted into the ground, using (2) trees as antenna to register the ground potentials and record them as voltage differences either between contact points in the ground and tree branches or vertically along the trunk by placing stainless steel or silver contacts into the xylem and phloem tissues at different heights along the tree trunks, and using (3) wires running the full length of a row of ground electrodes as antennas according to Eric Dollard’s work.
These measurements will be correlated with data from sensors measuring the oxidation potentials in the soils at different depths, with sensors recording temperature variations in boreholes deep enough to be screening from diurnal and seasonal surface temperature variations, and with parameters obtained from agricultural sources about “productivity “ of the soils.


Linear arrays in rectangular pattern as shown in Figure 1, possibly also in a triangular pattern
Alternatively, we consider a cluster of electrodes inserted into the ground, for instance groups of 4 pairs of electrodes of different length to set up Schlumberger-type 4-electrode arrays for measuring the conductivity of the soil.  To facilitate the accurate placement, we propose to use a “table” made out of steel or plastic as depicted in Figure 2, which will serve to guide the drill shafts during drilling the holes, into which the electrodes will be placed.

Each electrode will be designed to be waterproof as shown in Figure 3. Water proofing will be achieved by sealing off a PVC tube used as a sleeve.  Alternatively the central electrode will be placed into loosely fitting plastic tube and space between the tube and the central rod will be filled with liquid epoxy. The epoxy will cure to provide mechanical strength sufficient to insert the assembly into the ground.
Modification of Vadim Bobrovskiy Design
The published version of the Vadim Bobrovskiy electrode design (“Vad Electrodes”) consists of 4 stainless steel plates, typically 50 x 50 cm2, stacked on top of each other with 20-30 cm vertical distance in a 2.50 - 3 m deep holes dug into the ground, wide enough for a person to stand and work in them, typically 1 x 1 m2. As the stainless steel plates are placed into the holes, the dug-out earth is back-filled and compacted. This is repeated four times until the hole is totally filled. Contacts will be welded on and protected by epoxy. All stainless steel electrodes will be connected to water-proof BNC cables and to the surface of the Earth via a common conduit.  The Vad Electrodes are used to passively record geoelectric signals thought to be connected to seismic activity.

The Vad electrode design will be modified by replacing all 4 of the 50 x 50 cm2 solid stainless steel electrode plates by perforated stainless steel electrode plates large enough to fill the dug-out hole, typically   1 x 1 m2, with round or quadratic perforations large enough to assure continuity of the soil contacts. The rest of the installation procedure will be the same. 

The advantage of the modified Vad electrode design is that they can be operated either as a set of 4 electrodes for passively recording geoelectric potentials or as a 4-electrode Schlumberger-type station to measure the soil conductivity by applying an active voltage to the bottom and top electrodes and record the voltage drop across the two inner electrodes.  The use of stainless steel meshes instead of solid plates minimizes the distortion of the electric field.

The modified Vad electrodes can be operated in both modes by alternating between the passive mode (as in the original Vad electrode design) to recorded geoelectric potentials and the active Schlumberger-type mode to record the changes in the conductivity of the soil.


Four point resistivity measurements
A current is passed through the two outer contacts while the voltage is measured between the two inner contacts. Equivalent circuit for a four point measurement:
Current flows into the sample at contact 1 and comes out of the sample at contact 2.
Here RCi is the cable resistance and contact resistance of contact i.
Usually the contact resistance dominates over the cable resistance.
RS is the sample resistance and RM is the equivalent resistance of the voltmeter.
VS is the voltage across the sample and VM is the voltage measured by the voltmeter.

Electrode insertion into undisturbed soil
Another implementation of the Four Electrode Geopotential and Resistivity design envisions the insertion of solid or perforated stainless steel electrode plates into vertical slots cut into the ground with a chainsaw-like tool or a large diamond-tipped blade.  Depending on the geometry of the vertical slots and their depth, the vertical electrodes to be inserted will be rectangular or hemispherical, consisting of a solid or perforated stainless steel portion in the lower part and a support structure made of non-conductive materials in the upper part which also carries the leads for contacting the electrodes.  After emplacement the electrodes with will be set with a slurry of the same soil that was excavated during cutting the vertical slots. 
The advantage of this special design is that the electrodes are set into soil that is left undisturbed except for a thin layer of contact soil filled in as mud and naturally drained to the same moisture content as the surrounding soil.  A disadvantage may be that setting up such stations may require either large saw blades or a special design for a vertical chainsaw-like device to cut a rectangular vertical slot of sufficient depth, preferentially 2-3 m. Such a chainsaw-like device may work only in fine-grained sediments without pebbles and rocks.