Mapping the structural and tectonic objects of the Upper-Kama potassium salt deposit in the magnetic field

Abstract

Introduction. Petrophysical properties of rocks and strata reflect the long history of the Upper Kama potassium salt deposit (VKMKS) formation and development (about 300 million years) as well as its various endogenous and exogenous geological and geochemical processes. VKMKS geological structure as well as past and present processes at the field are effectively studied by geophysical methods. Experience has shown that, considering the gigantic area of the salt strata development and multi-layer potassium-magnesium salt deposits, high-precision and detailed geophysical studies performed on most of the VKMKS territory are most effective from a geological viewpoint, namely, gravity survey at a scale of 1 : 25,000 and aeromagnetic survey at a scale of 1 : 10,000 together with other geological and geophysical data. VKMKS structural-tectonic objects occurrence conditions and magnetic properties of their rocks and strata, especially magnetic susceptibility, form the petrophysical basis for the aeromagnetic survey applied to map the objects. The task of mapping structural-tectonic objects on the VKMKS territory in a magnetic field is a specific task of using aeromagnetic survey to map structural-tectonic objects in a weakly magnetic sedimentary cover of the entire Perm Cis-Urals. Methods of research includes studying and analyzing the research data of the Perm Cis-Urals sedimentary cover rock magnetic properties (magnetic susceptibility). The morphology of structural-tectonic objects magnetic field anomalies in the Perm Cis-Urals sedimentary cover and the morphology of VKMKS structural-tectonic objects magnetic field anomalies are studied and analyzed. Research results. The analysis of sedimentary cover rocks magnetic susceptibility and aeromagnetic survey data interpretation showed that the structural-tectonic objects of the cover create anomalies in the magnetic field. The anomalies exceed the intensity of three times the root-mean-square measurement error, and therefore are mapped with confidence. Conclusions. It is reasonable to use the data of areal high-precision aeromagnetic survey at a scale of 1 : 10,000 together with other geological and geophysical methods to improve the reliability of mapping such important structural and tectonic objects as tectonic faults of various ranks, from deep faults to fracture zones, at VKMKS.