History of the Oklahoma Geological Survey Observatory near Leonard, OK

       In 1960 the Jersey Production Research (Oil) Co built the original
       Observatory. This location was selected because it was seismically
       and magnetically quiet (ie no heavy industrial and traffic vibrations)
       and was in driving distance from their Tulsa headquarters.

       In 1965 Jersey gave the Observatory to OU in which it functioned
       as a small department in the College of Arts and Sciences.

       Through the generosity of the Sarky's Foundation, the quarter section
       (160 acres, 64.8 hectares) of leased land at the site was purchased
       for the State of Oklahoma.

       In 1976 a Nuclear Regulatory Commission grant through the Oklahoma
       Geological Survey provided for a statewide
       network of remote seismographs.

       In 1978, the Observatory became part of the Oklahoma Geological
       Survey, and was named the "Oklahoma Geophysical Observatory". It
       was soon renamed the "Oklahoma Geological Survey Observatory".

       During 1978, the last photopaper seismogram drum recorders were
       converted to heat writing (and some to ink writing).

       During 1989 a Dept. of Energy grant through Lawrence Livermore
       National Laboratories reworked a 760 meter deep borehole and
       placed vertical motion sensing seismometers at depths of five,
       432, and 748 meters below the surface. Triggered digital recording
       was provided near the borehole winch. Digital data was analyzed on
       the Observatory's first Unix workstation, a SUN 3/50.

       On June 1, 1990 Bush and Gorbachev signed a protocol that called
       for building a Soviet Nuclear Monitoring site near the Observatory Building.
       The Soviets (later Russians) were allowed to have a seismograph
       station there to record seismic waves from American, and an
       occasional British, underground nuclear blast in Nevada. Seven years
       later, after Russian-UK-US Nuclear testing ended, Russia released
       the site, and the United States turned the dollar-per-year leased
       land back to Oklahoma.
       Read "The Soviet General in Blue Jeans"

       The Defense Advanced Research Projects Agency (DARPA) provided
       a Sun SPARC 1+ workstation, and a six component seismograph
       system whose data was recorded, archived, and analyzed by the
       SPARC 1+. Soon, three remote seismic signals and three magnetic
       signals were added to this system which was called the Geneva
       system (It's exact name was GSE=Group of Seismic Experts). 

       Two years later, a DARPA grant (unclassified as all grants to the
       OGS Observatory have been) allowed a three-component (vertical, north-
       south, east-west) broadband (high fidelity-covers a wide frequency
       band) seismometer to be placed in a new 119 meter borehole. The 
       data from this seismometer was recorded on the Geneva system.

       In 1994 the Observatory became a station in the prototype International
       Monitoring System, which records seismic events and determines which
       are earthquakes, which are mining blasts, and which are underground
       nuclear tests. A grant from the US Air Force Technical Applications
       Center provided a Sun SPARC 20 and other equipment to aid in the
       monitoring. Digital seismograms were automatically emailed to the
       Prototype International Monitoring System. The Leonard facility was
       not made part of the permanent system, because Russians wanted the
       American stations further west.

       A 1996 DARPA/DEPSCoR grant reworked an uncased borehole. It was cased,
       cemented, and deepened to 864 meters. A newly designed ultra-broadband
       three-component seismometer was placed at the bottom of the hole. 
       This was the deepest broadband seismometer in the world. This
       seismometer had it's digitizers, data communication, and data 
       compression computer in the half-mile deep seismometer casing. Digital
       data was sent uphole and overland on optical fiber cable to a high
       end PC. This system, called the "Oklahoma System" recorded data
       at rates of 200 samples per second for each component (about 200
       megabytes per day). 

       In 1999 the Geneva System hardware and software became impossible
       to maintain. A rack digitizer was purchased from Guralp Systems in
       Reading, U.K. The digitizer cost six thousand dollars, weighs six
       pounds, and uses six watts of electric power. The rack digitizer
       digitizes data from three remote seismic stations at 200 samples
       per second. It also digitizes magnetic signals. The data is put on
       packets in a ring buffer and transmitted to the Oklahoma System PC.
       The digitizer drops each packet as soon as the PC sends an acknowledge
       for the packet. The rack digitizer has a GPS (Global Positioning
       System sattelite) receiver to give exact time for time tagging the 
       data packets. If any data is missed, or the sattelite time signal
       resyncs, the digitizer emails a message to staff.

       The Guralp made Oklahoma System software can communicate with any
       similar system in the world via the internet. OGS continually records
       one seismic channel from the University of Indiana. IU records
       three OGS signals.

       During 1999, permanent archiving of all digital data was switched
       from exabyte tapes (holding five gigabytes) to writable CDROMs.
       These CDROMs allow quick random access to all data, and will last
       much longer than tapes. Each CDROM holds 660 megabytes of compressed
       data. OGS uses about 100 CDROMs per year.