INTERPRETATION OF AIRBORNE ELECTROMAGNETIC AND MAGNETIC DATA IN THE 600 AREA

Geophysical data are frequently collected with a fine sample interval along traverse lines but with a coarser sampling in the direction perpendicular to the traverses. This disparity in sampling intervals is particularly evident when magnetic data are collected simultaneously with airborne electromagnetic data. Interpolating this traverse data onto an evenly spaced 2D grid can result in aliasing artifacts. For example, narrow linear structures that trend at acute angles to the traverse lines are imaged as a thick/thin/thick feature, looking like a boudinage or string of beads. Applying the anisotropic diffusion process to the resulting grids of data removes the artifacts, but the grid values close to the traverses are altered significantly from their initial values. The altered values are therefore not faithful to the original traverse data. The anisotropic diffusion algorithm can be modified to constrain values close to the original traverses. This modification removes the aliasing artifacts and produces a data grid faithful to the original traverse data. Some small artifacts along the traverse lines in the final data grid become more evident when grids containing derivative data (such as the analytic signal) are generated from the new data grid. However, these small traverse-line artifacts can be removed with standard microleveling procedures. The constrained anisotropic diffusion process is iterative, and some experimentation is required to determine the appropriate number of iterations.

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MAPPING GROUNDWATER RECHARGE ZONES AND LITHOLOGY WITHIN A MOUNTAINOUS HEADWATER CATCHMENT AREA OF THE SNOWY RANGE NEAR LARAMIE, WY WITH AIRBORNE ELECTROMAGNETIC AND MAGNETIC DATA

10.4133/sageep.27-010 ◽

2014 ◽

Author(s):

Bradley Carr ◽

Ryan Armstrong ◽

W. Steven Holbrook ◽

Jesper Pedersen ◽

Esben Auken

Keyword(s):

Groundwater Recharge ◽

Catchment Area ◽

Magnetic Data ◽

Airborne Electromagnetic ◽

Snowy Range ◽

Headwater Catchment

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Application of Airborne Electromagnetics and Magnetics for Mineral Exploration in the Baishiquan–Hongliujing Area, Northwest China

Remote Sensing ◽

10.3390/rs13050903 ◽

2021 ◽

Vol 13 (5) ◽

pp. 903

Author(s):

Shengjun Liang ◽

Siyuan Sun ◽

Hongfei Lu

Keyword(s):

High Efficiency ◽

Mineral Exploration ◽

Northwest China ◽

Ore Deposits ◽

Gansu Province ◽

Integrated System ◽

Magnetic Data ◽

Airborne Electromagnetic ◽

Airborne Electromagnetics ◽

Airborne Magnetic

Airborne electromagnetics is an effective and efficient exploration tool in shallow mineral exploration for its high efficiency and low cost. In 2016, airborne electromagnetic and airborne magnetic surveys have been carried out at the border of Xinjiang Uygur Autonomous Region and Gansu Province, the Northwest China. With an integrated system, the airborne electromagnetics and airborne magnetic data were collected simultaneously by AreoTEM-IV system from Aeroquest International Limited in Vancouver, BC, Canada, and the CS3 Cesium Vapor magnetometer from Scintrex in Concord, ON, Canada. About 3149 line-km of both data with 250 m line space were acquired. After data processing, the comprehensive analysis and interpretation of resistivity and magnetic anomalies has been carried out to infer lithological structure and outline the potential ore deposits. Verified by the ground surveys, seven outlined anomalies are consistent with the known ore sites, and one new gold deposit and several mineralization clues were found. The prospective reserves of gold are expected to exceed 10 tons. Besides, some prospecting target areas were outlined as the possible locations of copper–nickel deposits. The successful case shows the airborne magnetic data accords with geological structures, and the airborne electromagnetic method is effective in finding metal mineral resources, which can help to quickly identify potential ore targets with no surface outcrop.

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