Ben Warr wrote:
>Does anyone have any experience of characterising transect data in terms
I've worked some with multifractal characterization of subsurface fracture
apertures from horizontal oil wells. This data represents a scan-line or
linear traverse of the reservoir. The citation is
Belfield, W. (1994) Multifractal characteristics of natural fracture
apertures, Geophy. Research Letters, v.21, No. 24, p.2641-2644
>I am working on some soil penetrometer and surface
>topography transects, triggered by work done by Folurunso and earlier by
>Armstrong, (references available if required) The paper by Foluronso has
>used measures describing multifracticality, in order to cope with the
>seeimng situation of large scale modulations in strength being modified by
>small scale peturbations as the spatial resolution increases. Indeed my
>log-log plots of the variogram reveal distinct, separate linear regions.
>I understand that any suggestion of fractal, fractal-like or multifractal
>behaviour must be rigourously defined, is the suggestion of
>multifracticality simply a cop out for not being able to explain the
>breaks of slope in the log-log plot.
Actually, I'd say it's the other way around. The cop out is people
attempting to maintain a (mono)fractal relationship to data that deviates
>I am also aware that =the maths behind mul;tifractals is daunting.
>Are there any packages, algorithms lying around that can compute the
>necessary measures and legendre transformations that are required ?
It's relatively easy to program for yourself, but check the FAQ in the
SCI.NONLINEAR newsgroup. I believe that Tony Roberts at (I think) ANU has
some software at his web site. If you pose the question in the newsgroup
I'm sure he'll respond. Hope this helps.
ARCO Exploration & Production Technology
2300 West Plano Parkway
Plano, TX. 75075
*To post a message to the list, send it to ai-geostats@...
*As a general service to list users, please remember to post a summary
of any useful responses to your questions.