Electrical resistivity tomography Electrical resistivity tomography Electrical resistivity tomography (ERT) or electrical resistivity imaging (ERI) is a geophysical technique for imaging sub-surface structures from electrical resistivity measurements made at the surface, or by electrodes in one or more boreholes. If the electrodes are suspended in the boreholes, deeper sections can be investigated. It is closely related to the medical imaging technique electrical impedance tomography (EIT), and mathematically is the same inverse problem. In contrast to medical EIT, however, ERT is essentially a direct current method. A related geophysical method, induced polarization (or spectral induced polarization), measures the transient response and aims to determine
What If She's an Angel for the week of December 22, 2001. What If She's an Angel "What If She's an Angel" is a debut song written by Bryan Wayne, and recorded by American country music artist Tommy Shane Steiner. It was released in December 2001 as the first single from Steiner's debut album "Then Came the Night". The song reached number 2 on the "Billboard" Hot Country Singles & Tracks chart in May 2002, becoming his only hit single. It was also Steiner's only entry on the "Billboard" Hot 100, peaking at 39. "What If She's an Angel" debuted at number 52 on the