SeismographWASHINGTON, Jan 31 An earthquake of magnitude 4.5 hit the US state of Oklahoma, reports US Geological Survey (USGS). Tremors were recorded at 17.10 UTC time (20.10 Moscow time) seven kilometers northwest of the city of Medford (population about a thousand people). The epicenter of the earthquake lay at a depth of 7.9 kilometers. There were no reports of possible casualties or damage. Unusual consequences of a volcanic eruption
