Westerngeco L.l.p.

Schlumberger Technology Corporation

Christopher H Chapman

David Nichols

Johan O A Robertsson

James Rickett

Henk Keers

Walter Scott Leaney

Colin Thomson

Henrik Bernth

Rodrigo Fuck

John Olof Robertson

Adrian Alexander

Analysis of a seismic event, such as a microseismic event caused by hydraulic fracturing, comprises measuring seismic waves emitted by the event and converting the measurements into two values for magnitude of explosion or implosion and for magnitude of displacement discontinuity at a plane, together with two directions, a direction of a normal to the plane and a direction of displacement; where the two values and the two directions compose the moment tensor describing the seismic event. The measurements may be converted into the moment tensor and decomposed into the values and directions. The values and directions associated with several seismic events may be displayed concurrently on a graphic display as a graphic representation of multiple events, where each event may be depicted with magnitude of expansion or contraction represented by a volume and the plane represented as a laminar object.

Decomposition of the seismic moment tensor

Forward modeling is performed to compute a response of a target structure, the forward modeling accounting for distortion of a reflected signal from a reflector in the target structure. Waveform inversion is performed using the response of the forward modeling.

Waveform inversion using a response of forward modeling

A technique includes simulating seismic wave propagation based on an acoustic model and based on a result of the simulation, estimating an error between the result and another result obtained if the seismic wave propagation were simulated based on an elastic model. The technique includes based at least in part on the estimated error predicting the other result without performing the simulation based on the elastic model.

Correcting an acoustic simulation for elastic effects

A mehtod of determinig an integral of a function over an n-dimensional intergratio domain from the values of the function at a plurality of discrete data points within the integration domain, comprises partitioning the integration domain into a plurality of k-dimensional simplexes, where k&#x3c;=n. The function is integrated over each simplex, and the results are summed. The method may be applied in the processing of geophysical data such as, for example, seismic data, where the function is a function of at least the geophysical data. The processed data may then be used to obtain information about the physical properties of the earth's interior.

Geophysical data processing

Method of determining the response caused by model alterations in

Growing community of inventors

Great Shelford, United Kingdom

Christopher H Chapman