Seism acoustic studies with high resolution in the pilot well of the SAFOD seismic testing site were launched in 2010 with the support of William Ellsworth (USGS). Together, Valery Korneev (LBNL), Andy Snyder (USGS) and Askold Belyakov (IPE RAS), the new Magnetoelastic Inertial Geophone (MIG-3W) measuring the orthogonal components of the acoustic impact vector is placed in the well at coordinates 35.974257N, -120.552076W to the depth 1000 m and pressed to the casing. Experiments on monitoring seism acoustic emission and earthquakes have been started. At the end of 2015, the MIG-3W geophone and the registration system were upgraded. Preliminary amplifiers installed earlier in the geophone housing were located on the surface and a new registration system was used, which allowed to continue monitoring and recording the geophone signals in digital form with a sampling frequency of up to 100 kHz. In August 2016, a similar geophone MIG-3W was installed in the Russian Federation in the Vorotilovskaya Deep Well (VDW) at coordinates 56.967017N and 43.720605E at a depth of 1400 m in rocks without casing for long-term monitoring. Test registration for a similar scheme began on August 16. Two sessions were conducted, lasting 14 seconds and 30 minutes. In both wells (SAFOD and VDW), in addition to seismic signals, acoustic traces similar to traces of neutrinos were found, which are given in publications on acoustic neutrino detectors. In particular, measurements in the Atlantic Ocean region of the Bahamas using a hydro acoustic antenna have detected and published characteristic signals with a frequency of 50 kHz, which because of their shape were called "diamond". In wells, analogous signals with a sampling frequency of 10 kHz have an apparent frequency of about 5 kHz. In both cases, this is basically 10 to 12 oscillations with smoothly increasing and smoothly falling amplitudes. But the results were unexpected after the extraction of the device in May 2017 from the SAFOD well, when it was installed for urban testing (the second floor of a residential building in San Francisco). Short monitoring showed that, in addition to events like "diamond", events of a different form appeared. Additional express check in the basement on the seismic pedestal of the Institute of Physics of the Earth also showed the presence of signals like "diamond".
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