Posts Tagged ERA

3D modeling of ERA’s gradient survey results

Posted by on Friday, 14 January, 2011

UBC-GIF has finished 3D modeling of resistivity gradient survey data with EH3Dinv code (http://era-max.ca/examples.html, last two examples ). EH3Dinv is a computing code developed at UBC − GIF for inverting controlled source frequency-domain EM data to recover a 3D electrical conductivity (Inversion of 3D electromagnetic data in frequency and time domain using an inexact all-at-once approach. Eldad Haber, Uri M. Ascher, and Douglas W. Oldenburg. GEOPHYSICS, VOL. 69, NO. 5, 2004; P. 1216–1228).

The ERA’s technology, in brief, is “cross-disciplinary” – between frequency-domain and direct current (DC) concepts. The technology provides high resistivity resolution by grounded, non-contact and/or combined modes of electrical field measurements at 1.22-2500Hz. In comparison with DC method ERA equipment is several times more sensitive and in comparison with frequency-domain is defined as high-resolution.


High-Resolution ELECTRIC field measurements in any surface conditions

Posted by on Sunday, 24 October, 2010

The ERA’s technology of resistivity method exposes the best sensitive to subsurfce resistivity variations as well as a simplicity in theory and in field operations.

The non-contact measurements of electric field has been developed generally in Russia since 60-s - in 1963 for non-contact electrical profiling (B.G.Sapozhnikov), with 1981 – for geoelectrical sounding (A.S.Nahabtcev and A.I.Jabluchansky).

Now the idea has realized on the modern electronic and engineering basis in ERA equipment – transmitter, receiver, special antennas, “active” electrodes, ERA-MULTIMAX imaging system with “active” contacts. The equipment provides wide broad resistivity studies with  very high resistivity resolution.

The main applications – ground water, weak alteration processes, archeology, civil engineering, mineral exploration in any surface conditions in any electromagnetic noise including intown operations.