Ocean-Bottom Laser Seismograph

Sensors

Aleksandr Plotnikov¹  Stanislav Dolgikh¹  Grigory Dolgikh¹ 

[1] V.I. Il’ichev Pacific Oceanological Institute FEB RAS, 690041 Vladivostok, Russia;

关键词: bottom laser seismograph;    Michelson interferometer;    wind wave;    seiches;    vertical bottom displacements;    laser strainmeter;   

DOI  :  10.3390/s22072527

来源: DOAJ

【 摘 要 】

This paper describes an ocean-bottom laser seismograph, based on the modified laser meter of hydrosphere pressure variations, and designed to record vertical bottom displacements at the place of its location. Its measuring accuracy is about 1 nm, limited by the stability of the laser emission, which can be improved by using more advanced lasers. The purpose of this instrument is to measure the displacements of the seabed’s upper layer in the low-frequency sonic and infrasonic ranges. Theoretically, it can operate in the frequency range from 0 (conditionally) to 1000 Hz; the upper limit is determined by the operating speed of the digital registration system. We demonstrated the capabilities of the ocean-bottom laser seismograph while registering vertical bottom displacements caused by sea wind waves and lower frequency processes—seiches, i.e., eigenoscillations of the bay in which the instrument was installed. Comparison of experimental data of the bottom laser seismograph with the data of the laser hydrosphere pressure variations meter and the velocimeter—installed in close proximity—shows good efficiency of the instrument.

【 授权许可】

Unknown