Advanced Geophysical Operations and Services Inc. (AGCOS) participated in the 38th Annual Convention and Seminar on Exploration Geophysics, 20 – 22 October, 2016, Hyderabad, India. AGCOS presented the following papers:
Magnetovariational profiling method (MVP) was introduced into the field practice in the 1950-60s of the last century subsequent to the works of Parkinson (1959), Wiese (1965) and Schmucker (1970). At that time, low frequency variant (10-1000sec frequency range) was widely used for the detection and parameter estimation of large electrical conductivity anomalies in the Earth’s crust and upper mantle. The appearance of the 5th generation of electroprospecting equipment in the 1970-80s allowed MVP method to become regular add-on to magnetotelluric soundings (MT) in the 5-component variant. At the turn of the century, active implementation into field survey practice of the 5th generation digital multifunction EM instruments resulted in significant increase to the number of carried out AMT measurements, which were widely used for mining exploration. In turn, emphasized was the demand for the induction vector and tipper interpretation techniques. Besides the development of effective 2-D inversions, proposed were express interpretation methods which allowed to estimate the parameters (depth, conductivity, angle of inclination, etc.) of the conductive body during the course of the field survey. Consequently, as well as due to the application of precision field tripods for quick and accurate installation of the magnetic sensors, the 3-component MVP method became an effective independent ground electroprospecting technique for solving wide range of mining exploration tasks.
Appearance at the turn of the century of the 5th generation multifunction electroprospecting instruments has made significant contribution to the development of electroprospecting techniques. New properties of the equipment include – light weight, compact, low power consumption, simple operation, high accuracy of the recorded parameters. One of the defining features is the application of 24-bit ADC. Technological advancements in the microprocessor development and computer technology allowed significantly improving hardware capabilities of the 5th generation instruments, i.e. going to 5+. Super multifunction 4 and 8 channel receivers can be used in both autonomous and manual modes (operator control). Receivers have intuitive user interface implemented on touch-screen display and several communication modes with a PC, touchpads, and smartphone. Instruments have flexible configuration of electric and magnetic channels (channels are interchangeable), which allows to use same receiver for such seemingly incompatible methods – Electrical Profiling, IP, Electrotomography, TDEM, MT and MVP. Application of wideband high frequency ADCs and corresponding processors can significantly improve the frequency range of field investigations, as well as noise filtering capabilities. Data acquisition systems are equipped with a wideband electric and magnetic components EM field sensors, as well as a wideband portable transmitter.