Digital recording of seismic data on magnetic tape cartridges under microcomputer control

The goals of the Gulfrex are to perform marine exploration and to conduct research and development in the various facets of marine exploration. The Gulfrex is equipped with various geologic and geophysical data‐gathering instruments along with a highly sophisticated navigational package. Computerized control systems were designed to output data in real time so that preliminary interpretations could be made concurrently with data collection. One system, based on an EMR‐6130 computer, handles multichannel seismic data. This system includes routines for real‐time demultiplexing, normal moveout, stacking, and deconvolution. Output of demultiplexed data is to magnetic tape and optionally to paper records. Output of moveout‐corrected, stacked data is to a visual monitor and to magnetic tape via a PDP‐8 computer. Deconvolution may be applied to either the single‐channel traces or the stacked traces. A moveout‐corrected, CDP group is output to a paper record every 24 shots so that estimates of average velocities can be made for a normal‐moveout correction. Another system, designed for a PDP‐8 computer, is used to collect data from devices interfaced to it. These include single‐channel seismic data, gravity and magnetic measurements, and navigational measurements such as course, speed, ship position, and direction. Deconvolved single‐channel seismic data are plotted in real time on a visual monitor along with a corrected gravity profile, magnetic profile, speed, course, and time of day. A map of the ship’s course is plotted in real time on a drum plotter Inquiries may be made of the system for current position in latitude and longitude.

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An Interface for Digital Recording on Incremental Magnetic tape

IETE Journal of Research ◽

10.1080/03772063.1975.11450614 ◽

1975 ◽

Vol 21 (2) ◽

pp. 45-48

Author(s):

B.D. Chaudhary ◽

H.N. Mahabala ◽

K.M.L. Jha ◽

G.K. Mehta

Keyword(s):

Magnetic Tape ◽

Digital Recording

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RECOMMENDED STANDARDS FOR DIGITAL TAPE FORMATS

Geophysics ◽

10.1190/1.1440250 ◽

1972 ◽

Vol 37 (1) ◽

pp. 36-44 ◽

Cited By ~ 1

Author(s):

E. P. Meiners ◽

L. L. Lenz ◽

A. E. Dalby ◽

J. M. Hornsby

Keyword(s):

Seismic Data ◽

Digital Recording ◽

Field Recording ◽

Work Done

This paper is the result of work done by a subcommittee of the SEG Committee on Digital Recording Standards. It recommends an additional tape format for 9‐track field recording of seismic data and an optional use of 1600 bpi, as well as 800 bpi, for all field formats.

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Auditory discrimination of seismic signals from earthquakes and explosions

Bulletin of the Seismological Society of America ◽

10.1785/bssa0550010001 ◽

1965 ◽

Vol 55 (1) ◽

pp. 1-25

Author(s):

G. E. Frantti ◽

L. A. Levereault

Keyword(s):

Auditory System ◽

Seismic Data ◽

Magnetic Tape ◽

Path Length ◽

World Wide ◽

Propagation Path ◽

Seismic Signals ◽

Chance Performance ◽

Short Period ◽

Seismic Frequencies

Abstract Magnetic tape recordings of short-period seismic signals from approximately 200 earthquakes and explosions were time-compressed by a factor of up to 512 to shift seismic frequencies to the audible range. These seismic data include the inhomogeneities introduced by substantial variations in the locations of sources and receivers (world-wide), propagation path length (32 to 7000 km), and source magnitude (M = 0.5 to M = 6.5). Subjects were trained with a representative set of the “seismic sounds.” Auditory experiments were conducted to determine the ability of the human auditory system to distinguish between seismic signals from earthquakes and explosions. The results of the experiments suggest that a trained listener can identify approximately two-thirds of the seismic sounds presented, where one half corresponds to chance performance.

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The Seismic Research Observatory

Bulletin of the Seismological Society of America ◽

10.1785/bssa0660062049 ◽

1976 ◽

Vol 66 (6) ◽

pp. 2049-2068 ◽

Cited By ~ 2

Author(s):

Jon Peterson ◽

Howell M. Butler ◽

L. Gary Holcomb ◽

Charles R. Hutt

Keyword(s):

Seismic Data ◽

Broad Band ◽

Computer Processing ◽

Preliminary Evaluation ◽

Digital Recording ◽

Digital Form ◽

Data Resource ◽

Long Period ◽

Period Data ◽

Mass Position

abstract Thirteen advanced seismograph systems, called Seismic Research Observatories (SRO), are being installed as part of a program to upgrade the worldwide seismic data network. The SRO system was created by combining a recently developed broad-band borehole seismometer and a software-controlled recording system. The seismometers are being installed at a depth of 100 meters to avoid wind-generated noise in the long-period band. A seismometer output that is flat in acceleration between periods of 1 and 50 sec is used to produce both short- and long-period data that are recorded on analog drum recorders and in digital form on magnetic tape. Very-long-period data, obtained from the seismometer mass position output, can be recorded as well. Digital recording of gain-ranged data provides an amplitude of nearly 120 dB. Preliminary evaluation of the SRO data system indicates that major design objectives have been met. The network of SRO stations will be an important new data resource for seismological investigations, especially for those studies that require computer processing of the data.

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The use of digital recording on magnetic tape for the study of γ-rays from resonant neutron capture in platinum

Nuclear Physics ◽

10.1016/0029-5582(59)90004-5 ◽

1959 ◽

Vol 14 (2) ◽

pp. 212-221 ◽

Cited By ~ 19

Author(s):

J.R. Bird ◽

J.R. Waters

Keyword(s):

Neutron Capture ◽

Magnetic Tape ◽

Digital Recording ◽

Γ Rays

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And I Alone Survived

Mechanical Engineering ◽

10.1115/1.2000-mar-6 ◽

2000 ◽

Vol 122 (03) ◽

pp. 84-86 ◽

Cited By ~ 7

Author(s):

Jack Raplee

Keyword(s):

Magnetic Tape ◽

Federal Aviation Administration ◽

Black Box ◽

Air Traffic ◽

Digital Recording ◽

Commercial Aircraft ◽

Recording Technology ◽

Flight Data ◽

Rotation Rates

This article focuses on the black box that is becoming smaller, smarter, and more useful as a safety tool in the aviation sector. Although endurance regulations have gone virtually unchanged for several years since the Federal Aviation Administration (FAA) first required the units on all commercial aircraft, the most notable has been the advent of digital recording technology. Digital recorders can record more parameters over longer periods of time using less energy than older magnetic tape recordings. Today, this kind of information is used not only to investigate an aviation accident, but to increase the safety of flying at a time when air traffic has grown significantly. The FAA is conducting a FOQA Demonstration Study in cooperation with major U.S. airlines. Based on digital flight data recordings, the study provided information on items such as unusual autopilot disconnects excessive rotation rates on takeoff, unstabilized approaches, and hard landings.

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