Seismic reflection scale model facility

Abstract

A two-dimensional, physical seismic model system has been developed at Flinders University for laboratory studies into elastic wave propagation through a variety of simulated geological structures. The scale model facility produces useful (and inexpensive) data for training purposes as well as for testing of new signal processing and imaging algorithms. The digital recording equipment is under computer control which enables trace gathers to be acquired, and subsequently processed, quickly and accurately. The piezoelectric transducers have been designed to provide good resolution (100 kHz bandwidth) and stability, and facilitate the recording of both P and S waves. The entire system has been carefully calibrated to enable deconvolution of the seismograms for the effects of the various instrument components as well as the nature of the input source waveform. The simple reflection experiments which are reported here demonstrate the high performance of the ultrasonic facility in imaging a small cavity, a horizontal linear target of finite extent, a fault, and a basement mound. The resulting seismic sections clearly show the prominence of diffractions, and the importance of S waves (mode conversions) in structural interpretation.