نوع مقاله : مقاله پژوهشی
1 دانشیار ژئومورفولوژی، دانشکده جغرافیا، دانشگاه تهران
2 دانشجوی کارشناسی ارشد هیدروژئومورفولوژی، دانشکده جغرافیا، دانشگاه تهران
3 دانشجوی کارشناسی ارشد زمینشناسی ساختمانی و تکتونیک، دانشکده علوم زمین، دانشگاه تربیت مدرس
4 دانشجوی دکتری ژئومورفولوژی- مدیریت محیطی، دانشکده جغرافیا، دانشگاه تهران
عنوان مقاله [English]
Sudden movement towards the development of quantitative geomorphology in recent decades was, leading to the development of statistical methods and mathematical models to describe the geomorphological processes. This led to the establishment of a wide range of geomorphological little useful the interpretation of changing processes - poured have been tectonic activity in the study areas. (Avena et al, 1967; Buonasorte et al, 1991; pike, 1993; Merta, et al, 2005). Assessment of buildings and landforms of earth during its foundation, subject knowledge has been a tectonic geomorphology (Stanley et al., 2000). Endless competition between tectonic processes that have the desire to create ripples and surface processes that tend to eliminate and smooth out unevenness, the core concept of is tectonic geomorphology.
Eastern region strait of Hormuz (MINAB fault on its eastern and southern part of the fault system) affected by tectonic forces are, a variety of forms that morphotectonic check how the emergence of and these shapes correlated with tectonics of the region can help to solve many of the questions about the evolution of tectonic and geomorphological is related to the in area of Iran.
The data used in this research includes the geological maps 1:250000 and 1:100000 of the region for identification of the faults, the digital elevation model data (DEM of 30 meters of the region) for mapping the location of the region, and the information of Landsite Satellite and Google Earth images to measure the parameters and assess the tectonic evidences of the region. With the help of the listed data, as well as GIS and Google Earth applications, the morphometric parameters of the anticline is computed, which contains this three main parameters: the triangular facets, wine glass, and anticline front sinuosity.
Result and discussion
In this study, a total of 251 triangular facets on 5 anticline were identified of these a number 88 triangular facets in the anticline 1, 32 triangular facets in the anticline 2, 43 triangular facets in the 3,65 triangular facets in the 4, and 23 triangular facets in the anticline 5 Identify and were measured. Also in this the study, 185 wine glass valley identified in the anticlines, the number of there were , 64 wine glass valley in the anticline 1, 18 wine glass valley in the anticline 2, 28 wine glass valley in the anticline 3, 47 wine glass valley in the anticline 4, and 28 wine glass valley in the anticline 5. According to Table 4, Sinuosity index in anticline 1 is less on the northern slopes of the southern slopes; also the index of the anticlines number 2 and 3 is less on the northern slopes of the southern slopes. But the index, in the anticline 4 and 5 this less in the southern slope.
Generally, the results indicate that the tectonic activity in the southern edges of the anticlines is higher, and among the studied anticlines in the two parameters of wine glass valleys and mountain front sinuosity, the anticline number 1 has the highest tectonic activity (Table 5), and according to the reviewed evidences, and the dispersal of these evidences showed in Figures 3 and 4, it was determined that the most density of the morphotectonic evidences, like the displacement of the formations, the staircase faults, and the redirection of the rivers, has been observed in the area of and around the anticline 1, which indicates that the tectonic activity in this region has been more. In general, the results of parameters and the examined evidences indicate that the active tectonic has been dominant in the area. After anticline 1, the anticlines that have had the most tectonic activity are anticline number 4, anticline number 3, and anticline number 2, respectively, and anticline number 5 has had the lowest tectonic activity. The concordance between the conducted field studies and literature review, and the results of the parameters, and the distribution and type of evidences, indicate the proper application that these parameters have in evaluating the tectonic activity. The results of this study can be used for land use planning including risk mapping, prioritization of immunization in areas with higher risk measures, in order to achieve the stabilization of the environment. Based on the conducted field surveys, an earthquake of magnitude 5 on the Richter scale (May 1392) in the upstream basin of the studied anticlines caused the evacuation of many rural housing by residents because of fear of recurrence of the earthquake. The evacuation was to the extent that some of the villages lost more than 80 percent of their population, and the evacuated population flooded in the neighboring towns. The loss of agricultural land in rural areas, the increase of the potential for soil loss, and the loss of self-employment opportunities in the villages are the other consequences of this earthquake and the same earthquakes that may hit the area in the future.