We have developed a linearized algorithm to invert noisy 2-D magnetotelluric data for subsurface conductivity structures represented by smooth boundaries defining sharp resistivity contrasts. We solve for both a fixed number of subsurface resistivities and for the boundary locations between adjacent units. The boundary depths are forced to be discrete values defined by the mesh used in the forw...

We used magnetotelluric data from 352 sites in Botswana to derive a country-wide electrical conductivity model of the crust and upper mantle structure. A robust methodological scheme 3D inversion were with unprecedented spatial coverage. The results show interesting features, including major cratonic blocks mobile belts Botswana. distinctive resistive structure was imaged southwest Botswana, wh...

This study presents the ankle ligament strains and ankle joint moments during an accidental injury event diagnosed as a grade I anterior talofibular ligament (ATaFL) sprain. A male athlete accidentally sprained his ankle while performing a cutting motion in a laboratory setting. The kinematic data were input to a three-dimensional rigid-body foot model for simulation analyses. Maximum strains i...

the radio magnetotelluric (rmt) method is one of the most widely used electromagnetic (em) methods which employs artificial time varying electric and magnetic fields at the surface of the earth for imaging conductivity. the radiomagnetotelluric method proposed by goldstein and strangway (1975) is based on measuring one set of horizontal electrical and perpendicular magnetic components. after th...

The clay and non-clay minerals have been identified by XRD analysis. The non-clay minerals include quartz, crystobalite, orthoclase, microcline, plagioclase, calcite, siderite and dolomite, and the clay minerals include kaolinite (52.39%), illite (36.39%) and illite-smectite mixed layer minerals (11.21%). Kaolinite is the most dominant component in the clay mineral assemblages. The clay mineral...

Shear-wave velocity ( ) is an important parameter used for site characterization in geotechnical engineering. However, dispersion curve inversion is challenging for most inversion methods due to its high non-linearity and mix-determined trait. In order to overcome these problems, in this study, a joint inversion strategy is proposed based on the particle swarm optimization (PSO) algorithm. The ...

The adsorption of polymers on clay is important in many applications. However the mechanisms of poly(ethylene oxide) (PEO) adsorption n smectite and its effect on suspension rheology are not well elucidated at present. The aim of this study was to investigate the mechanisms esponsible for PEO sorption on smectite and how this impacts on dispersive behavior of smectite suspension. The results in...