|
|||||
|
|
Using helicopter electromagnetic data to predict groundwater quality in fractured crystalline bedrock in a semi-arid region, Northeast Brazil |
|
| Authors: | Oderson Antônio de Souza Filho Adalene Moreira Silva Armando Zaupa Remacre Sérgio Sacani Sancevero Anne Elizabeth McCafferty Mônica Mazzini Perrotta |
| Institution: | 1. Geological Survey of Brazil, and University of Campinas, Rua Voluntários da Pátria, 475, sala 10. Curitiba, CEP: 80.020-926, PR, Brasil 2. Applied Geophysics Laboratory, Institute of Geosciences, University of Brasília and Institute of Geosciences, University of Campinas, Campus Darcy Ribeiro, Asa Norte, Brasília, CEP: 70.910-900, DF, Brasil 3. Institute of Geosciences, University of Campinas, R. Jo?o Pandiá Calógeras, 51, P.O. Box 6152, Campinas, SP, Brazil, CEP: 13083-970 4. Institute of Geosciences, University of Campinas and ROXAR Inc, Rua Costa, 31, apt. 20, S?o Paulo, SP, Brazil, CEP: 01304-010 5. Crustal Imaging & Characterization Team, US Geological Survey, Box 25046, Denver Federal Center Mail Stop 964, Denver, CO, 80225-0046, USA 6. Remote Sensing Division, Geological Survey of Brazil-CPRM, Rua Costa, 55, S?o Paulo, SP, Brazil, CEP: 01304-010 |
| Abstract: | Geostatistical modeling, using airborne and borehole electromagnetic data, was used to estimate electrical conductivity in groundwater within fractured paragneisses and migmatites in a semi-arid climate in northeastern Brazil. Despite the geologic heterogeneity of crystalline aquifers, the use of high resolution helicopter electromagnetic (HEM) data enabled the characterization of groundwater electrical conductivity where data from drilled wells were insufficient. The tacit assumption is that HEM measurements can be used to relate rock electrical conductivity to groundwater electrical conductivity. In this study, the HEM data were used as an external drift variable in non-stationary estimation and stochastic simulation to identify the variability of groundwater electrical conductivity. Validation tests, comparing predicted values for groundwater conductivity with measurements in new wells, confirmed the success of these models in locating fresh groundwater sources in crystalline bedrock. |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ | |