17 documents found, page 1 of 2

Comparison of electromagnetic induction and electrical resistivity tomography i...

Electromagnetic induction (EMI) and electrical resistivity tomography (ERT) are geophysical techniques measuring soil electrical conductivity and providing insights into properties correlated with it to depths of several meters. EMI measures the apparent electrical conductivity (ECa, dS m−1) without physical contact, while ERT acquires apparent electrical resistivity (ERa, ohm m) using electrodes. Both involve ...

Contribution of the time domain electromagnetic method to the study of the Kala...

ABSTRACT: The Cunene Province (Southern Angola) is facing recurrent and pluriannual droughts. Surface water supply could be reinforced using the groundwater resources of the multilayered aquifer systems (MAS) hosted in the siliciclastic sediments of the Kalahari Group. The MAS were first identified in the early 2000s in Northern Namibia and recently in the Cunene Province, by studies of the PLANAGEO project bas...

Contribuição do método geofísico eletromagnético no domínio de tempo para o est...

SUMMARY: Under the scope of project PLANAGEO, a geophysical survey using the time domain electromagnetic (TDEM) method was planned and conducted. This survey aimed to contribute to the hydrogeological conceptual model of the KOS and KOH aquifer systems, to validate the 1960 data electrical resistivity reprocessing and to define the future location of deep boreholes. The TDEM survey allowed identifying different...

3D electrical structure definition of aquifer systems in the Kalahari basin in ...

ABSTRACT: The Kalahari-Ohangwena transboundary aquifer system, recently identified in Northern Namibia, comprises 3 major aquifers with very different characteristics. The shallowest is discontinuous and with limited reserves, but it has local importance in water supply for the population, since it is easy to reach, and often presents good hydrochemical quality. An intermediate deeper aquifer is characterized b...

Integrated Geophysical Methods for Shallow Aquifers Characterization and Modelling

Integrated Geophysical Methods for Shallow Aquifers Characterization and Modelling

New evidence of Late Cretaceous magmatism on the offshore central West Iberian ...

ABSTRACT: The West Iberian Margin (WIM) is a key example of a magma-poor passive margin, punctuated by several postrift magmatic manifestations that are part of the Late Cretaceous Atlantic Alkaline Province. In this work, potential field (gravity and magnetics) data, constrained by 3D multichannel seismic reflection data, are used to describe and characterise the geometry and nature of magmatic features locate...

Regional calibration and electromagnetic conductivity imaging for assessing the...

Determinação da salinidade e sodicidade do solo por métodos de indução eletroma...

O excesso de sais solúveis na solução do solo (salinidade) ou o domínio do sódio no complexo de troca (sodicidade) são fenómenos que levam à degradação das funções do solo. É essencial monitorizar as áreas de risco de forma a prevenir ou mitigar os processos de salinização e os seus efeitos negativos. Os métodos de indução eletromagnética (EMI), aliados a algoritmos de inversão, têm sido usados para analisar o ...

Assessing soil salinity dynamics using time-lapse electromagnetic conductivity ...

LezíriaGrandedeVilaFrancadeXira,locatedinPortugal,isanimportantagriculturalsystemwhere soil faces the risk of salinization due to climate change, as the level and salinity of groundwater are likely to increase as a result of the rise of the sea water level and consequently of the estuary. These changes can also affect the salinity of the irrigation water which is collected upstream of the estuary. Soil salinity...