Document Type : Full length article
Department of Natural Geography, Faculty of Natural Geography, Isfahan University, Isfahan, Iran
Department of Spatial Information Systems and Remote Sensing, Lanjan Branch, Islamic Azad University, Isfahan, Iran
Soil Conservation and Watershed Management Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran.
A B S T R A C T
From the point of view of geo structure, the location of Khanmirza plain in the folded Zagros zone in the south of the Dena fault and the presence of piezometers protruding from the soil, the presence of springs etc. are signs of crustal movement on the surface. The purpose of this research is to use geological information, seismological information, and satellite images in order to obtain a view of the tectonic activity of the present era in the Khanmirza plain, as well as to simplify the displacement calculation, to evaluate the displacement of the earth's surface and the parameters affecting this displacement, and providing a suitable model for this plain. In this study, the displacement rate of the earth's surface for 8 years (2003-2010) was calculated using D-InSAR radar images and radar interferometry. The effective parameters of the DEM elevation layer, slope, slope direction, profile curvature, surface curvature, distance from The road, the distance from the fault, the density of the fault, and the earthquake's intensity were obtained from the GIS environment. Furthermore, multivariate regression in the SPSS environment presented the best model for this plain. In this environment, the 8-year displacement rate was considered dependent, and the rest of the parameters were considered independent variables. The results were challenged in the STEPWISE model. The results showed that among the 13 methods, the 13th method is the best regional model for calculating crustal mobility in this plain by providing the best correlation coefficient of 0.826, a determination coefficient of 0.682, an adjusted determination coefficient of 0.675, and a standard error of 99%. Moreover, the average movement in this basin is a 10 cm rise for 8 years.
In recent decades, the sudden movement towards developing quantitative geomorphology has led to progress in statistical methods and mathematical models to describe geomorphological processes. The wide scope of the work has led to the foundation of quantitative geomorphological methods useful in the interpretation and interpretation of transformational-morphological processes and in the study of active tectonic areas. The earth is a dynamic system that changes, and transformation is one of its characteristics. Almost no area on its surface has not been affected by new earth-building activities during the last few thousand years. Active land construction is changing the shape of the earth's surface.
Much research has been done in Iran on tectonic evaluation with geomorphic indicators. Among the works that can be mentioned: Ramsht et al. (2013) evaluated the accuracy and correctness of geomorphological indicators using geodynamic data in the Jajroud watershed northeast of Tehran. The geomorphological indices and geodynamic data results indicate that the basin studied in this research is active in new land construction. However, the level of activity of new land construction movements is different everywhere, and the upstream areas of the basin are more active in this respect.
The purpose of this research is to use geological and seismological information in a GIS environment and satellite images to obtain a view of the tectonic activity of the present era in Khanmirza plain. Also, the research focuses on simplifying the displacement calculation, evaluating the amount of land surface displacement and parameters affecting this displacement. Moreover, finally, it seeks to provide a suitable model in the SPSS environment for this plain. The innovation of this research is to evaluate the amount of displacement with non-morphological indicators and measure their relationship with crustal movements.
In this article, geological and topographical data, Envisat satellite images, and various software such as SPSS, ARC MAP, and Envi 3.5 have been used to present a regional model for the Khanmirza basin.
Results and discussion
This article was designed in five basic steps, the first of which is the preparation of GIS layers required by the region. Considering that the physiographic conditions of the basin, such as slope, slope direction, profile curvature, surface curvature, distance from the road, distance from the fault, the density of the fault, and earthquake intensity are less considered in the topic of crustal mobility, in the article we tried to use from these parameters, new relations should be defined. Their correlation level with displacement value can be obtained. For this purpose, first, all these maps were drawn in the ARC MAP environment; in the next step, with the help of 22 radar interferometry images in the Envi environment and with the help of the Sarscape plugin, the amount of displacement was calculated for 8 years. The final map of the amount of displacement was obtained in GIS Came. In the present study, radar images from 2003 to 2010 were exerted to investigate displacement rates. What can be seen from this 8-year-old map is the 33-centimeter drop of this plain in the east and south, which is marked in red, and the 59-centimeter rise of the mountains on the west side of the map, which is marked in blue.
In the next step, the correlation between the displacement rate and the parameters was calculated in the SPSS environment using the Pearson method. The results show the highest correlation of the displacement rate with the fault density, slope, earthquake intensity, direction of slope and surface curvature, distance from the road, distance from the fault, profile curvature, and DEM, respectively. In the fourth step, the best displacement model of the region was presented in the SPSS environment with the help of the stepwise model. The dependent variable of the eight-year displacement rate and the independent variables include DEM elevation layers, slope, slope direction,
surface curvature, profile curvature, distance from the road, distance from the fault, fault density, and earthquake intensity in the form of 9 independent variables. Model 13, with the highest correlation coefficient, coefficient of determination, adjusted coefficient of determination, and standard error, was recognized as the best model. Moreover, in the last step, with the help of the formula obtained from the fourth step and the final displacement map in the ARC MAP environment, an estimated regional model map was prepared based on the indicators.
Due to the location of Iran in an active tectonic region, which is in the direct collision of two Eurasian-Arabian plates in the north-northeast direction and also in the southeast region in the indirect collision of the Indian Arabian plates, it causes movement and displacement in different proportions in the shells, and Various parts are continental and oceanic. The location of Khanmirza plain in terms of geo structure in the folded Zagros zone and the south of Dena fault and the presence of piezometers protruding from the soil and springs and other signs of crustal movement have created a destructive effect on the level of underground water and agriculture in this plain. In this research, in order to evaluate the displacement of the earth's surface and the parameters affecting this displacement, as well as to provide a suitable model by calculating the 8-year displacement rate of the earth's surface (2003-2010) using D-InSAR radar images and radar interferometry. The amount of elevation was 59 cm, subsidence was 33 cm, and the average displacement was 13 cm. Therefore, to better understand the causes of this event, effective parameters such as DEM elevation layer, slope, slope direction, profile curvature, surface curvature, distance from the road, distance from the fault, the density of the fault, earthquake intensity were calculated on this displacement in the GIS environment. Moreover, to measure the relationship between these factors and this event in the SPSS environment, through Pearson's correlation, the value of the relationship between each parameter and displacement rate was calculated, and the highest correlation between fault density and displacement rate was obtained. Following correlation measurement with the help of multiple linear regression, a stepwise model was presented in SPSS software, and the output of this model was 13 proposed methods. The 13th method, with the best correlation coefficient of 0.826, a determination coefficient of 0.682, an adjusted determination coefficient of 0.675, a standard error of 0.0099, and a significance level of 99% among these 13 methods, is the best regional model for calculating shell mobility. It is on the level of this plain. This map's estimated regional model of the uplift value coefficient is about 40 cm, and the subsidence value is 21 cm. Also, the average change of 10 cm elevation in this plain was calculated with this method. The results of this research can be used in different planning related to the watershed, including identifying and introducing the areas involved in the risk of earthquake and subsidence, investigating and studying underground water sources, etc. Maintaining the water balance is the most important solution to prevent land subsidence in this area, which can be achieved by controlling unlicensed wells and preventing excessive water extraction
There is no funding support.
All of the authors approved thecontent of the manuscript and agreed on all aspects of the work.
Conflict of Interest
Authors declared no conflict of interest.
We are grateful to all the scientific consultants of this paper