Estimation of the orientation of stress in the Earth’s crust without earthquake or borehole data

AbstractMechanical stress acting in the Earth’s crust is a fundamental property that is important for a wide range of scientific and engineering applications. The orientation of maximum horizontal compressive stress can be estimated by inverting earthquake source mechanisms and measured directly from borehole-based measurements, but large regions of the continents have few or no observations. Here we present an approach to determine the orientation of maximum horizontal compressive stress by measuring stress-induced anisotropy of nonlinear susceptibility, which is the derivative of elastic modulus with respect to strain. Laboratory and Earth experiments show that nonlinear susceptibility is azimuthally dependent in an anisotropic stress field and is maximum in the orientation of maximum horizontal compressive stress. We observe this behavior in the Earth—in Oklahoma and New Mexico, U.S.A, where maximum nonlinear susceptibility coincides with the orientation of maximum horizontal compressive stress measured using traditional methods. Our measurements use empirical Green’s functions and solid-earth tides and can be applied at different temporal and spatial scales.

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Measuring SHmax with Stress-Induced Anisotropy in Nonlinear Anelastic Behavior

10.21203/rs.3.rs-288404/v1 ◽

2021 ◽

Author(s):

Andrew Delorey ◽

Götz Bokelmann ◽

Christopher Johnson ◽

Paul Johnson

Keyword(s):

Spatial Scales ◽

Fundamental Property ◽

Nonlinear Susceptibility ◽

Induced Anisotropy ◽

New Approach ◽

The Earth ◽

Wide Range ◽

Source Mechanisms ◽

Horizontal Compressive Stress ◽

Stress Induced Anisotropy

Abstract Mechanical stress acting in the Earth`s crust is a fundamental property that has a wide range of geophysical applications, from tectonic movements to energy production. The orientation of maximum horizontal compressive stress, SHmax can be estimated by inverting earthquake source mechanisms and directly from borehole-based measurements, but large regions of the continents have few or no observations. Available observations often represent a variety of length scales and depths, and can be difficult to reconcile. Here we present a new approach to determine SHmax by measuring stress induced anisotropy of nonlinear susceptibility. We observe that nonlinear susceptibility is azimuthally dependent in the Earth and maximum when parallel to SHmax, as predicted by laboratory experiments. Our measurements use empirical Green’s functions that are applicable for different temporal and spatial scales. The method can quantify the orientation of SHmax in regions where no measurements exist today.

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Improving of electrical channels for magnetotelluric sounding instrumentation

Geoscientific Instrumentation Methods and Data Systems ◽

10.5194/gi-4-149-2015 ◽

2015 ◽

Vol 4 (2) ◽

pp. 149-154 ◽

Cited By ~ 1

Author(s):

A. M. Prystai ◽

V. O. Pronenko

Keyword(s):

Electric Field ◽

Electric Fields ◽

Deep Structure ◽

Experimental Tests ◽

Magnetotelluric Sounding ◽

Earth’S Crust ◽

Geomagnetic Variations ◽

The Earth ◽

Wide Range ◽

Earth's Crust

Abstract. The study of the deep structure of the Earth's crust is of great interest for both applied (e.g. mineral exploration) and scientific research. For this the electromagnetic (EM) studies which enable one to construct the distribution of electrical conductivity in the Earth's crust are of great use. The most common method of EM exploration is magnetotelluric sounding (MT). This passive method of research uses a wide range of natural geomagnetic variations as a powerful source of electromagnetic induction in the Earth, producing telluric current variations there. It includes the measurements of variations of natural electric and magnetic fields in orthogonal directions at the surface of the Earth. By this, the measurements of electric fields are much more complicated metrological processes, and, namely, they limit the precision of MT prospecting. This is especially complicated at deep sounding when measurements of long periods are of interest. The increase in the accuracy of the electric field measurement can significantly improve the quality of MT data. Because of this, the development of a new version of an instrument for the measurements of electric fields at MT – both electric field sensors and the electrometer – with higher levels relative to the known instrument parameter level – was initiated. The paper deals with the peculiarities of this development and the results of experimental tests of the new sensors and electrometers included as a unit in the long-period magnetotelluric station LEMI-420 are given.

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The Correlation of Roasting Conditions in Selective Potassium Extraction from K-Feldspar Ore

Minerals ◽

10.3390/min9020109 ◽

2019 ◽

Vol 9 (2) ◽

pp. 109 ◽

Cited By ~ 5

Author(s):

Mete Tayhan Serdengeçti ◽

Hüseyin Baştürkcü ◽

Fırat Burat ◽

Murat Olgaç Kangal

Keyword(s):

Economic Benefits ◽

Earth’S Crust ◽

Optimum Conditions ◽

Agriculture Industry ◽

Wide Range ◽

Ceramic Glass ◽

Leaching Experiments ◽

Roasting Temperature ◽

Earth's Crust ◽

Direct Leaching

Feldspar minerals are essential ingredients for the glass and ceramic-glass industries. The potassium element found in certain proportions in the composition of K-feldspar minerals has a fundamental function in the growth of plants. The production of potassium fertilizers is mostly made from the soluble minerals, which are located in lakes. Despite having a huge area of use in the agriculture industry, the reserves of these salts are limited and not evenly distributed in the earth’s crust. Due to the high availability of feldspar reserves in the earth’s crust, the production of potential potassium salts can provide a wide range of social and economic benefits. In this study, potassium extraction from a feldspar ore, which contained microcline, albite, muscovite, and quartz, was studied using chloridizing (CaCl2) roasting followed by leaching. Direct leaching experiments were also performed on the sample by adapting various solvents. To emphasize the importance of roasting before the dissolution process, different parameters such as particle size, roasting temperature, and duration, as well as the feldspar/CaCl2 ratio, were tested. Under the optimum conditions (i.e., −106 microns, 850 Co, 60 minutes, 1:1.5 feldspar:CaCl2), 99% of the potassium was successfully extracted from the ore feed.

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On the susceptibility of feebly magnetic bodies as affected by compression

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1922.0056 ◽

1922 ◽

Vol 101 (712) ◽

pp. 445-452 ◽

Cited By ~ 13

Keyword(s):

Mechanical Stress ◽

Compressive Stress ◽

Cross Section ◽

Complex Problem ◽

Earth’S Crust ◽

The Subject ◽

Earth's Crust ◽

Rock Specimens

This communication undertakes an investigation of the complex problem which is presented by the effects of mechanical stress upon the susceptibility, retentivity and other properties of magnetic substances. The present experiments are confined to compressive stress, and its effects upon the susceptibility of certain rock specimens. It was felt that an investigation into this part of the subject might possibly throw some light upon the susceptibility of the earth’s crust as affected by the enormous forces with which it has to contend, and their variations. It is unfortunate that, owing to the nature of rock specimens, the compressive stress has been limited to about 1200 kgrm. per square centimetre, but, nevertheless, some interesting results have been obtained, and these are recorded in the present paper. All the specimens are in the form of short bars about 4 cm. in length, whose cross-section is either square, being 1 cm. across each side, or 1 cm. in diameter; and, throughout the work, the compressive stress has been applied in the direction coinciding with the length of the bar. The susceptibility has been measured ( a ) in the direction of the stress and ( b ) at right angles thereto.

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The relationship of the relative abundance of masses of granites and rhyolites in the earth’s crust with the regularities of the rheology of the granitic magmas

Петрология ◽

10.31857/s0869-5903275496-502 ◽

2019 ◽

Vol 27 (5) ◽

pp. 496-502

Author(s):

E. S. Persikov

Keyword(s):

High Pressures ◽

Earth’S Crust ◽

Relative Distribution ◽

Chemical Basis ◽

Physical Chemical ◽

Wide Range ◽

Effusive Rock ◽

Earth's Crust ◽

Relative Prevalence ◽

Relationship Of

Many years ago, V.S. Sobolev suggested that the reason for the relative prevalence of intrusive and effusive rock masses in the earth’s crust lies in the regularities of viscosity of water-bearing magmas in a variable field of temperatures and pressures. Alas, in those years it was not possible to solve this problem on a quantitative physical-chemical basis, since experimental and theoretical studies of the viscosity of such melts at high pressures were just beginning. In the present work, new regularities of the viscosity of near-liquid water-bearing acidic magmas in a wide range of thermodynamic parameters and depths of the Earth’s crust (1–30 km) is established using the structural-chemical model of reliable and correct predictions and calculations of the viscosity of magmas of virtually any composition. It determined that these regularities really are a quantitative physical-chemical basis explaining the reason for the relative distribution of masses of intrusive and effusive rocks of acidic composition in the earth’s crust.

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Editorial for the Special Issue “The Rietveld Method in Geomaterials Characterisation”

Minerals ◽

10.3390/min11080814 ◽

2021 ◽

Vol 11 (8) ◽

pp. 814

Author(s):

Thomas N. Kerestedjian

Keyword(s):

Raw Materials ◽

Rietveld Method ◽

Earth’S Crust ◽

Fundamental Importance ◽

Special Issue ◽

Wide Range ◽

Earth's Crust

The raw materials obtained from the Earth’s crust (Geomaterials) are of fundamental importance for a wide range of industries [...]

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Improving of electrical channels for magnetotelluric sounding instrumentation

Geoscientific Instrumentation Methods and Data Systems Discussions ◽

10.5194/gid-5-63-2015 ◽

2015 ◽

Vol 5 (1) ◽

pp. 63-81

Author(s):

A. M. Prystai ◽

V. O. Pronenko

Keyword(s):

Electric Field ◽

Deep Structure ◽

Mineral Exploration ◽

Experimental Tests ◽

Magnetotelluric Sounding ◽

Earth’S Crust ◽

Geomagnetic Variations ◽

The Earth ◽

Wide Range ◽

Earth's Crust

Abstract. The study of deep structure of the Earth's crust is of great interest for both applied (e.g. mineral exploration) and scientific research. For this the electromagnetic (EM) studies which enable to construct the distribution of electrical conductivity in the Earth's crust are of great use. The most common method of EM exploration is magnetotelluric sounding (MT). This passive method of research uses a wide range of natural geomagnetic variations as a powerful source of electromagnetic induction in the Earth, producing there telluric currents variations. It includes the measurements of variations of natural electric and magnetic fields in orthogonal directions at the surface of the Earth. By this, the measurements of electric field are much more complicated metrological process, and namely they are limiting the precision of MT prospecting. This is especially complicated at deep sounding when measurements of long periods are of interest. The increase of the accuracy of the electric field measurement can significantly improve the quality of MT data. Because of this the development of new version of instrument for the measurements of electric field at MT – both electric field sensors and the electrometer – with higher relative to the known instruments parameters level were initiated. The paper deals with the peculiarities of this development and the results of experimental tests of the new sensors and electrometer included as a unit in the long-period magnetotelluric station LEMI-420 are given.

Download Full-text