Oklahoma Geological Survey annotated 24 hour seismograms for year 2006.

SHORT EXPLANATION: These seismograms were produced by a broadband seismometer in the Leonard walk-in vault. They show only vertical (ie, not East-West or North-South) ground motion. The seismograms show 24 horizontal lines, one for each hour of ground motion. The data is filtered so that it shows mainly surface waves from distant earthquakes. Some earthquakes are labeled (average 3.4 based on 2001 JAN through NOV) to show the earthquake region, the distance from Leonard in great circle degrees (eg. D=120), and magnitude (eg 5.1mb). Definite earthquake surface waves of earthquakes not located at the time the figure was posted may be marked with a ?. Some of the seismograms with large surface waves which may obscure other smaller earthquakes are SIGNED ROOT COMPRESSED This consists of taking the root (from the 1.1 root to the 3.0 root) of each number while keeping the original sign (plus or minus) of the number.

LONG EXPLANATION: hardware and software details. The epicenters used in annotation are from these three sources: 1. SED = Swiss Seismological Service/Schweizerischer Erdbebendienst seismo.ethz.ch/redpuma/redpuma_ami_list.html 2. USGS = U.S. Geological Survey, National Earthquake Information Center. neic.usgs.gov/neis/bulletin/ 3. KNET = Kyrgyzstan Real-time Broadband Array epicenter.ucsd.edu/~quake_KN/bulletin.txt SED epicenters include USGS and KNET epicenters, as well as epicenters from several other sources. These web pages are processed by a NAWK program which calculates the distance to Leonard, Oklahoma U.S., and the expected arrival times of P/Pdif/PKP and LR. Source 1. tends to have lower magnitudes than source 2. If the type of magnitude was not labelled by the source, it is listed as simply "M" (eg 5.1M).

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