R.Estival, D.Léandri, Y.Lacroix Evaluation of geophone ground coupling using geophone/hydrophone comparison |
Acoustic bulletin, Vol. 17 ¹ 2, (2015) |
| Ground coupling defines the transfer function from ground motion to geophone motion. Ground coupling can be described using a variety of models, which must all be adequately parametrized before being used on data. The ocean bottom seismometers and ocean bottom cables are the devices confronted to ground coupling problems. Besides the velocity measurements made via geophones, the mentioned two types of devices allow pressure measurements due to presence of hydrophones. In this paper, we introduce a method that searches iteratively for the velocity boundary conditions which, when applied to a finite element model, allow the simulation results to fit with pressure data measured by the hydrophones. The iterative process is supported by a genetic algorithm. The obtained velocity values provide the evaluation of ground coupling of the geophones. |
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KEY WORDS: geophone, ground coupling, hydrophone, velocity boundary conditions, acoustic pressure, iterative process, genetic algorithm |
| TEXT LANGUAGE: English |