Scientific- Research Quarterly of Geographical Data (SEPEHR)

Scientific- Research Quarterly of Geographical Data (SEPEHR)

Precise Geological Mapping as a New Method for Analyzing Surface Faults

Document Type : Research Paper

Author
Mahdi Modiri
Associate Professor of Urban planning, Malek-Ashtar University of Technolog
Abstract
In order to evaluate the potential for earthquake surface fracture, a new application of highly accurate geological mapping with total electronic station is presented. This method makes it possible to detect secondary faults, which represent 30-cm-long vertical displacement that does not appear on the surface. These very small faults do not have signs and symptoms of topology, so it is likely that they will not be considered though they show the existence of faults in the range of installations and movements.
This method involves mapping of points in geological features and accurate and comprehensive analysis of computer details and field operations of abnormalities at the heights of mapped points. General abnormalities are considered at high altitudes that are mainly consisting of normal and inverted fault. However, this method can be used for longitudinal slip faults as well.
This method provides the conditions where geological data can easily be integrated into GIS and 3D analysis of details of small structure features can be achieved; field data can be analyzed in the profiles of three dimensional diagrams and in maps that are made using cartographic software.
The ability of this method to identify faults with slight displacement allows the types of metamorphism, reduction in displacement of the direction of small and divergent faults, located at the two extremities of large and ordinary faults, single-slope bends and transverse structures between faults can be determined.
Keywords
precise geological survey
Earthquake
digital Map
surface rupture and faults
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Scientific- Research Quarterly of Geographical Data (SEPEHR)
Volume 17, Issue 67
Autumn 2008
Pages 2-12