among all the geophysical techniques, the magnetotelluric method has improved considerably in recent years and is widely being used in hydrocarbon exploration especially in regions where reflection seismic has difficulties. areas which are covered with high velocity rocks in the near surface are most popular cases. a huge high resolution magnetotelluric investigation was conducted in the sehqan...

This paper describes the application of approximate methods to invert airborne magnetic data as well as helicopter-borne frequency domain electromagnetic data in order to retrieve a joint model of magnetic susceptibility and electrical resistivity. The study area located in Semnan province of Iran consists of an arc-shaped porphyry andesite covered by sedimentary units which may have potential ...

this paper describes the application of approximate methods to invert airborne magnetic data as well as helicopter-borne frequency domain electromagnetic data in order to retrieve a joint model of magnetic susceptibility and electrical resistivity. the study area located in semnan province of iran consists of an arc-shaped porphyry andesite covered by sedimentary units which may have potential ...

Pertamina has conducted geothermal exploration in Sumatra showing that the depths to the top of most of the geothermal reservoirs are about 1000-2000 meters. Previous geophysical exploration work by Pertamina emphasized the use of DC-resistivity methods such as the Schlumberger method. However, these techmques can typically only penetrate to a depth of less than 1000 meters and are too shallow ...

in this paper, fourteen mt stations along a profile perpendicular to the main geological structure were used in order to identify the geology of sabalan geothermal field including the extension of the surface cap-rock and clay-cap layers. the mt data collected between 1-8192 hz is of useful quality and provides good control on the surface layers in many areas. it means that reliable modeling sh...

In the last decades, helicopter-borne electromagnetic (HEM) method became a focus of interest in the fields of mineral exploration, geological mapping, groundwater resource investigation and environmental monitoring. As a standard approach, researchers use 1-D inversion of the acquired HEM data to recover the conductivity/resistivity-depth models. Since the relation between HEM data and model ...

over the past three decades helicopter-borne electromagnetic (hem) measurements have been used to reveal the resistivity distribution of the earth's subsurface for a variety of applications. hem systems include a “bird” or sensor containing one or more pairs of transmitting and receiving coils. the separation between the rigidly mounted transmitting and receiving coils of a coil-pair typic...

geophysical techniques remain the only ways to remotely and non-destructively sense the earth’s near subsurface and as such have the most promising prospect for rapid and accurate detection of underground tunnels. today, electrical resistivity and seismic refraction geophysical methods have been greatly developed to identify structures and underground cavities. in this study, the ability of the...