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HingeInflex: a MATLAB-based method for precise selection of the hinge and the inflection points in folds

Published online by Cambridge University Press:  30 October 2009

DEEPAK C. SRIVASTAVA  and
VIPUL RASTOGI
DEEPAK C. SRIVASTAVA*
Affiliation:
Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand, India
VIPUL RASTOGI
Affiliation:
Department of Physics, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand, India
*
*Author for correspondence: dpkesfes@iitr.ernet.in
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Abstract

Subjectivity in visual selection of hinge and inflection points leads to significant errors in analyses of fold shapes in profile sections. This article gives a method for precise determination of these points. The method: (1) imports a fold image into Matlab, (2) digitizes points on the image, (3) increases the number of available points by using an interpolation algorithm, (4) fits a polynomial curve to the points, and (5) searches for the hinge and the inflection points mathematically. Tests on several folds confirm that the ‘HingeInflex’ is a rapid, robust and user-friendly method for precise selection of the hinge and inflection points.

Keywords

fold shape analysispolynomial fittinghinge pointinflection pointMatlab
Type
Original Article
Information
Geological Magazine , Volume 147 , Issue 2 , March 2010 , pp. 233 - 241
Copyright
Copyright © Cambridge University Press 2009

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