A Faghih; A Jamshidi; A Nohegar
Abstract
The existence of lateral propagation of folds above blind reverse faults is an important hypothesis and is generally accepted. In this research, the growth pattern of active folds (e.g., Herang and Kuh-e-Namaki anticlines) in the Fars Arc located in the Zagros Fold-Thrust Belt is investigated from tectonic ...
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The existence of lateral propagation of folds above blind reverse faults is an important hypothesis and is generally accepted. In this research, the growth pattern of active folds (e.g., Herang and Kuh-e-Namaki anticlines) in the Fars Arc located in the Zagros Fold-Thrust Belt is investigated from tectonic geomorphology point of view. The main goal of this research is to use geomorphometric indices such as drainage pattern, drainage density, drainage basin asymmetry factor and stream length-gradient to determine direction of lateral fold growth with a special focus on the process of linkage of several different fold segments. Geomorphological studies show that some folds in the Zagros did not develop from a single embryonic fold but by lateral linkage of several different fold segments. The linkage type (linear or en-echelon linkage) of different fold segments depends on the alignment of the initial embryonic folds. Investigation of geomorphometric indices in the study area shows that the Herang anticline resulted from lateral growth and en-echelon linkage of three embryonic folds while the Kuh-e-Namaki anticline resulted from linear growth of a single embryonic fold and cannot be considered as a result of linkage of several different segments.
A. Lashkari; M. R. Ghassemi; M. Qorashi
Abstract
The Caspian (Khazar) fault is the boundary between the Caspian plain and AlborzMountain. As a major tectonic feature, this fault may be considered as the northern mountain front fault of the AlborzRange. Subsidence of the Caspian Sea in north, uplift of the Alborz Mountain, and its over thrusting on ...
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The Caspian (Khazar) fault is the boundary between the Caspian plain and AlborzMountain. As a major tectonic feature, this fault may be considered as the northern mountain front fault of the AlborzRange. Subsidence of the Caspian Sea in north, uplift of the Alborz Mountain, and its over thrusting on southern part of South Caspian basin has occurred along the Caspian fault. In this paper, a segment at the fault which is located between longitudes 52° 30׳ and 53° 00׳ - in the northern part of geological map of Qaemshahr - is considered as a segment that does not outcrop. This paper introduces the general structural and morphotectonic characteristics of this zone and describes the characteristics of the active anticlines (growing folds) and morphotectonic effects in this zone such as effects on rivers.
