Cases

The Arctic

The Case Study of using ocean-bottom seismographs based on R-sensors' sensors in the Arctic to assess seismic hazards.

To find a solution, there were used the first results of several pilot deployments of the ocean-bottom seismographs developed by Shirshov Institute of Oceanology and Ilyinskiy A.D., a sole proprietor, in 2018 – 2020.

The seismographs are equipped with two types of broadband molecular-electronic sensors of two modifications: CME-4111 (120 sec - 50 Hz) and CME-4311 (60 sec - 50 Hz). The sensors were made by R-sensors, Russia.

The research was conducted in the Laptev sea under different conditions.

The main characteristics of the broadband molecular-electronic sensors such as permissible installation angles, operation temperature ranges, sensitivity and dynamic ranges appeared suitable for obtaining records under the Arctic conditions to solve the seismological problems.

The Case Study of using R-sensors' molecular-electronic seismic sensors (pdf) on Sakhalin and Kunashir islands in cooperation with Institute of Marine Geology and Geophysics of the Far Eastern branch of the Russian academy of sciences. 

The project aimed at studying seismicity of Sakhalin with the use of seismic sensors of a new type. The challenge was to study the structure of the lithological section's top and to clarify compositions and properties of the soil at the equipment locations. 

The proposed solution included broadband seismometers CME-6111, data loggers NDAS-8226 and hydrophones - those were specially developed for the study. 

The results showed that R-sensors' molecular-electronic instruments in terms of the main metrological parameters (frequency and dynamic ranges, self-noise levels) reach the best models of electromechanical instruments and can be used in processing ongoing seismological information. 

The study was conducted by explorers of Institute of Marine Geology and Geophysics and the Sakhalin branch of Geophysical Servey (far-eastern Russia).

A new seismic monitoring system for historical buildings was developed and tested in Isfahan, one of the oldest cities in Iran (read the Case Study, pdf). The system consists of R-sensors' seismometers and geophones and Geoarmatech's seismic recorders. 

The research goal was to develop a new seismic monitoring system for historical buildings in Isfahan and compare the results of the general vibration assessment (by Federal Transportation Association, or the FTA method) measurements to the measurements at the vibration source. 

For that goal, a 1-year vibrations monitoring was conducted. The solution included development of a new monitoring system consisting of analog seismometers CME-4211 and geophones MTSS-1001 (R-sensors) and recorders GeoArm-R24 (Arman Fanavaran Zamin also known as Geoarmatech). 

The results confirmed feasibility of a new monitoring system which is providing more reliable predictions than those of the FTA measurements. The results also showed the water table level has a strong impact on vibrations and accuracy of predictions.

Journal of Science and Technological Developments published a research article titled 'Autonomous Geohydroacoustic Ice Buoy of New Generation'. 

A geohydroacoustic ice buoy is a finalized measuring autonomous instrument including an analog one-component molecular-electronic measuring instrument of the CME-4211V type (based on the MET), a power source, a seismic data logger of the NDAS-8224 type. 

Seismic sensors based on the MET (molecular-electronic technology) are highly reliable instruments. They do not require neither any special means or methods for transportation and deployment, nor service or mass locking. Moreover, these instruments are well-suited for field surveys and for quick deployment of seismic network. 

The article provides the comparison results of long laboratory tests for Streckeisen, Guralp and CME (R-sensors) as well as confirms operability of the new instrument and its compliance to the world's analogues in its key parameters. 

The authors of the article are prominent scientists holding Grand PhDs and PhDs.

The Case Study of using R-sensors' accelerometers (pdf) in cooperation with Teknik Destek Grubu based in Turkey. 

The challenge was to supply and install a real-time structural health monitoring system – in compliance with the new regulations – to monitor and record seismic vibrations of two high-rise structures in Istanbul, Turkey. 

The solution included strong motion accelerometers MTSS-1031A and MTSS-1033A (R-sensors) and TESTBOX-2010 digitizers and MONSTER (Monitoring of Structures in Real Time) software by Teknik Destek Grubu. 

This type of systems is used not only against earthquakes but also against other loads such as aging, deep excavations and so on.

The Seismic Instruments journal published an article titled 'Feasibility of Using Molecular-Electronic Seismometers in Passive Seismic Prospecting: Deep Structure of the Kaluga Ring Structurefrom Microseismic Sounding' by The Schmidt Institute of Physics of the Earth founded in Moscow in 1928. 

The microseismic sounding survey was carried out along a geophysical profile crossing the central part of the structure with simultaneous data acquisition by molecular-electronic and conventional seismometers at each measurement point. Experimental data on the propagation of Rayleigh waves along the curvilinear surface were collected. 

The feasibility of using molecular-electronic seismometers by R-sensors for passive seismic studies were confirmed by the results of a comparative analysis of the vertical geophysical cross sections, which reveal upper crustal heterogeneities, and by the results of a series of laboratory tests.

The Journal of Seismology published an article of "New seismic array solution for earthquake observations and hydropower plant health monitoring". Some unique data was acquired by the METR-03 rotational seismometer. 

The rotational oscillation sensor is named as a significant addition to the security system which is installed in conjunction with accelerometer in the turbine hall and can increase the efficiency of cavitation hazard detection to a new level.

Three-component compact seismometers CME-4311 jointly with other equipment were used for large-scale tests of ice-rinks durability. 

The tests results were published in the article of 'Large-Scale Tests of ice-rinks durability for a bend in the Kara and Laptev seas' (in Russian) in Rosneft's science and technology journal. The article was written by a group of authors of the Rosneft oil company, Arctic and Antarctic Research Institute, Arctic scientific and design center for shelf technologies. 

The developed parameters monitoring of ice-rinks deformation processes is recommended to apply on drifting ices in real time as early warning systems that will allow to reduce risks when working in polar expeditions, to increase people's safety on ice and to avoid equipment losses.

The tests of a subsea autonomous wireless seismic station developed by the Center for Molecular Electronics of MIPT and R-sensors were held near the Golubitsky mud volcano at the Azov Sea shore (Krasnodar region, south of Russia) in the expedition organized by The Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences. 

Owing to its water-proof design, that subsea seismic station can operate in transition zones including partial or full immersion. The built-in Li-Ion accumulator allows several days of autonomous recording while the installed Wi-Fi wireless interface gives an opportunity to read recorded data remotely. A GNSS/GPS receiver detects the station's position and helps adjust a reference generator. The sensing unit is based on the modified MTSS-2003 three-component high gain seismic sensors.

One-component seismic sensor MTSS-1021 successfully passed tests in Orenburg region of Russia. At the experimental work, a signal induced by an all-terrain vibrator was recorded simultaneously by a row of 240 sensors at a 50-meter step. Thus, the 2-D profile along the line of over 300 kilometers was consecutively collected. The results were verified by comparing it with the data obtained with conventional moving-coil geophones GS-20DX-1. The tests were performed by 'Sibgeotekhservis' and our subsidiary company 'Seismotronika' on the request of The Federal agency for subsoil resources management of Russia. 

The MTSS-1021 sensor is designed by R-sensors and Seismotronika as a part of SCOUT multichannel seismic wireless data acquisition system by Special Design Bureau for Seismic Instrumentation ("SKB SP"), Saratov, Russia. The sensor shares similar parameters with the MTSS-1001 but has self-contained power supply and is equipped with exchangeable Li-Pol accumulators. 

Apart from the main tests, the ability of the METR-01 rotational sensors to register the Rayleigh waves directly was tested and verified. The information on the surface waves is sufficient for eliminating their interference with the desired signal.