SeismicHandler: programmable multichannel data handler for interactive and automatic processing of seismological analyses

This paper introduces a new computational algorithm for the partial correlation coefficients of a linear system given the covariance of its output when excited by a white input noise. Although derived from Levinson's well-known procedure, the proposed algorithm does not make use of the usual parameters in the linear prediction recursion. It may be implemented using fixed point arithmetics. Application to speech waves is emphasized.

A fixed point computation of partial correlation coefficients

The mathematical theory underlying one of the techniques currently being used in linear prediction of speech is developed from an inner product formulation. This formulation produces a unified framework for studying the properties of autocorrelation equations. In particular, the solution and stability of the auto-correlation equations are studied in detail. Experimental stability results for finite word length analysis of speech are also presented.

On autocorrelation equations as applied to speech analysis

Wedescribetheacquisition,processing,andinversionofa multitransient electromagnetic MTEM single-line survey, conducted in December 2004 over an underground gas storage reservoir in southwestern France. The objective was to find a resistor corresponding to known gas about 500 m belowthesurveyline.Indataacquisition,wedeployeda100-m inline bipole current source and twenty 100-m inline potentialreceiversinvariousconfigurationsalongthe5-kmsurvey line; we measured the input current step and received voltages simultaneously. Then we deconvolved the received voltagesforthemeasuredinputcurrenttodeterminetheearth impulse responses.We show how both amplitude and traveltimeinformationcontainedintherecoveredearthimpulseresponses reveal the lateral location and approximate depth of the resistive reservoir. Integrating the impulse responses yields step responses, from which the asymptotic DC values were estimated and used in rapid 2D dipole-dipole DC resistivityinversiontofindthetopofthereservoir.Aseriesofcollated 1D full-waveform inversions performed on individual common midpoint gathers of the step responses position the top and bottom of a resistor corresponding to known gas in thereservoirandalsoobtainthetransverseresistance.Theresults imply that the MTEM method can be used as a tool for hydrocarbonexplorationandproduction.

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Multitransient electromagnetic demonstration survey in France

An algorithm (which does not involve the usual Riccati-type equation) for computing the gain matrices of the Kalman filter is presented. If the dimension k of the state space is much larger than that of the observation process, the number of nonlinear equations to be solved in each step is of order k rather than $k^2$ as by the usual procedure.

Frank F. Caden

Papers

Statistical Communication and Detection with Special Reference to Digital Data Processing of Radar and Seismic Signals