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J.N. Towle

Publications and source records attributed to J.N. Towle.

3 recordsLinked to original sources
USGS1983

VLF electromagnetic investigations of the crater and central dome of Mount St. Helens, Washington

A very low frequency (VLF) electromagnetic induction survey in the crater of Mount St. Helens has identified several electrically conductive structures that appear to be associated with thermal anomalies and ground water within the crater. The most interesting of these conductive structures lies beneath the central dome. It is probably a partial melt of dacite similar to that comprising the June 1981 lobe of the central dome. ?? 1983.

Journal of Volcanology and Geothermal Research↗
USGS1980

New evidence for magmatic intrusion beneath the Rio Grande rift, New Mexico

An analysis of the geomagnetic variation field across the Rio Grande rift has identified two concentrations of telluric current flow beneath the rift caused by channeling of telluric currents in electrically conductive structures in the crust and upper mantle. A shallow conductor nearly coincides with a very strong reflection in a high-resolution seismic-reflection profile across the central Rio Grande graben which has been attributed to a lens at mid-crustal depth. The deep (>30 km) conductor is 200 km wide and may indicate anomalously high temperatures and, by inference, a thinning of the lithosphere beneath the rift.

Geological Society of America Bulletin↗