Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Fractal Analysis of Nehbandan Fault System

Document Type : Original Research Paper

Authors
Sohrab Shahriari
Mohammad Mahdi Khatib
Department of Geology, Faculty of Geosciences, Shahid Beheshti University, Tehran, Iran
Abstract
The Nehbandan dextral strike-slip fault system in east Iran, constitutes structural boundary province between Sistan and the Lut. The general trend of this fault- system is north-south, creating a complicated structural process in the region. It's general picture is sigmoidal, having variable sheared zone, as well as a few tens of kilometers of displacement. The distinct manifestation of this fault- system are the effects of various movements during the Quaternary, as well as, terminal oblique movements. Fractal analysis, according to the method of counting- squares, and plotting logarithmic diagram i.e.- abundant logarithmic squares of the network, being based on the length of square of the picture on the general scheme of the above-mentioned fault, indicates that, in the central portion, the fractal dimension is 1.06, in Sahl Abad sector is 1.402, in Birjand sector is 1.450 and lastly for the whole faulted zone the fractal dimension is 1.645.
When the dimension of the squares of the network, along the shortest fault becomes less, within the scale of the maps, hence the fractal dimension increases accordingly in the unlined areas of distribution. Consequently, this is an indication of structural complexity of the sheared zone in this fault. Moreover, increase in fractal dimension in each terminal oblique zone is indicative of a widespread stress- field, and a decrease in the curvature of terminal fault.
Keywords
Fractal Analysis, Nehbandan Fault

Subjects

 
Cello, G., 1997- Fractal Analysis of a Quaternary array in the central Apennineso- Italy., J. structural Gelogy, 19-(7)945-953.
Cowie, P.X.et al. 1996- Scaling laws for fault and fracture populations analysis and applications. J. Structural Geology. 18
Mandelbrot, B.B., 1983- The Fractal Geometry of Nature., W.H.Freeman New York.
Tirrul et al. 1983- The Sistan Suture Zone of eastern Iran. Geol. Surv. Iran 94, 134-150.
Turcotte, D.L., 1992- Fractals and chaos in Geology and Geophysics., Cambridge University Press, Cambridge.
Wojtal, S. F., 1996- Changes in fault displacement populations correlated to linkage between faults., J. Structural Geology. 18, 265-279.
 
Scientific Quarterly Journal of Geosciences
Volume 6, 23-24
Spring & Summer 1998, Vol. 6, No. 23-24
Autumn 1998
Pages 32-39