HR: 0800h
AN: T51C-0700    [Abstracts]
TI: Connectivity test across deformation bands: results from field pumping experiments in Tucano Basin, NE Brazil
AU: * Medeiros, W E
EM: walter@dfte.ufrn.br
AF: Universidade Federal do Rio Grande do Norte, Departamento de Fisica, Natal, RN 59078970, Brazil
AU: do Nascimento, A F
EM: aderson@dfte.ufrn.br
AF: Universidade Federal do Rio Grande do Norte, Departamento de Fisica, Natal, RN 59078970, Brazil
AU: Silva, F C
EM: fernando@geologia.ufrn.br
AF: Universidade Federal do Rio Grande do Norte, Departamento de Geologia, Natal, RN 59078970, Brazil
AB: Sandstones of the Ilhas Group in Tucano Basin, NE Brazil, commonly present outcropping fault associated deformation bands. In one of these outcrops, with approximately 1km length and 15m thick three wells were drilled and in situ permeability measurements were done across the outcrop surface. The connectivity tests were performed with one well at one side of the fault zone and the two others at the other side. Two tests were performed and at each test - whilst one well was pumped downdraws were monitored at the other two remaining wells. The permeability profiles revealed a huge variation of permeability of up to four orders of magnitude. Nonetheless, the well pumping tests revealed a moderate connectivity across the deformation band since the observed stationary downdraw at monitoring well on the opposite side of the fault zone was a considerable fraction (~1/8) of the downdraw observed in the pumped well. These results indicate that there is 3D connectivity in the field scale across the deformation band.
UR: http://www.dfte.ufrn.br
DE: 1828 Groundwater hydraulics
DE: 1899 General or miscellaneous
DE: 5104 Fracture and flow
DE: 5114 Permeability and porosity
DE: 8100 TECTONOPHYSICS
SC: Tectonophysics [T]
MN: 2007 Fall Meeting