A LEAST-SQUARES METHOD FOR MULTISURFACE UNFOLDING

Geologic structures are mostly known from scattered data, and structur es such as folds or faults are drawn in between by using interpolation , which is often based on geologically poor assumptions, such as smoot hness. The need for more accuracy leads to restoration techniques in w hich more realistic assumptions are introduced. In this context we hav e tested a multisurface unfolding procedure. We use a least-squares fo rmulation involving the following criteria: initial horizontality, bed -length conservation (during slip on bedding) and local volume conserv ation. Weighted optimization of these criteria gives a compromise betw een them if they are conflicting. We have successfully tested the meth od on various theoretical examples and on an analog model: the 'paperb ack experiment'. (C) 1997 Elsevier Science Ltd.