ROTATIONAL SEISMOMETER

Abstract

Elastic wave theory predicts that the elastic waves generated by an earthquake and other seismic events include a measurable component of horizontal elastic rotation. Several rotational seismometers have been designed to measure this rotational component. The first design consisted of a large inertial ring of mercury terminated in a coaxial set of stand pipes housing capacitive transducers to sense the displacement of the mercury in the stand pipes. The second design consisted of a continuous inertial ring of water with a thermistor transducer to detect flow within the pipe. The third design consisted of a continuous inertial ring of water with a thin paddle placed in the path of flow. Problems encountered involved spurious signals due to a 'flexible' pipe, electronic noise and drift, temperature stabilization, and moisture penetration into the transducers. The capacitive transducer seemed to be the most promising, and experimentation is continuing using this transducer within a rigid steel pipe.

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Document Details

Document Type
Technical Report
Publication Date
Mar 15, 1970
Accession Number
AD0712632

Entities

People

  • Charles A. Dann
  • Peter W. Rodgers

Organizations

  • University of California, Berkeley

Tags

Communities of Interest

  • Advanced Electronics
  • Space

DTIC Thesaurus Topics

  • Angular Acceleration
  • Capacitors
  • Detectors
  • Displacement
  • Earthquakes
  • Elastic Waves
  • Electronics
  • Gages
  • Measurement
  • Moisture
  • Rotation
  • Seismometers
  • Semiconductors
  • Strain Gages
  • Thermistors
  • Transducers
  • Waves

Readers

  • Control Systems Engineering.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Thermal Physics or Thermal Science.

Technology Areas

  • Microelectronics
  • Microelectronics - Microelectromechanical Systems