INVESTIGATION OF ACTIVE TECTONICS IN ZAGROS TRUSTH BELT FARSAN REGION

Q: How can I download an article?

To download an article from SID, first log in to the site, search for the article title, and click on the 'Download Article' option.

Q: How can I download an ISI article?

To download an ISI article on SID, enter the keyword or article title in the search bar, view the relevant results, click on the desired article, and select the 'Download Article' option.

Q: How can I access the SID database?

To access the SID database, visit SID.ir, create an account, and log in to access scientific resources.

Q: Is downloading articles from SID free?

Some articles on SID are available for free, while others require payment. Details are specified on the article's page.

SEIF A.; KHOSRAVI GH.

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

Journal Paper

Paper Information

Journal: Physical Geography Research Year:2011 | Volume:- | Issue:74 Page(s): 125-146

Download Full-Text

Persian Verion

View:

1,813

Download:

Cites:

Information Journal Paper

Title

INVESTIGATION OF ACTIVE TECTONICS IN ZAGROS TRUSTH BELT FARSAN REGION

Author(s)

SEIF A. | KHOSRAVI GH. | Issue Writer Certificate

Keywords

MAIN ZAGROS FAULTQ3

IAT INDEXQ3

FARSAN BASINQ3

ACTIVE TECTONICS INDEXESQ3

HIGH-ZAGROSQ3

SANANDAJ-SIRJANQ3

Abstract

Introduction: Concerns of earth sciences, tectonic geomorphology with its own methodology is too. The main subject in tectonic geomorphology science is the study of measurable forms and landforms produced by tectonic signals. Since judgment about pale oseismological characteristics of an area cannot be only based on instrumental paleosizemology records and/or historical earthquake, so the study of surfacial landscapes and landforms is very important. ACTIVE TECTONICS INDEXES are advantageous tools for assessment and investigation of tectonic status of mobile zones. ACTIVE TECTONICS INDEXES are such as stream length gradient, drainage basin asymmetry, drainage basin shape, hypsometry integral and ratio of valley- floor width to valley height.The, MAIN ZAGROS FAULT is one of the major as well as active faults of our country which has been prudes many earthquakes in around area.In this study FARSAN BASIN, which consists of two zone structural of SANANDAJ-SIRJAN and HIGH-ZAGROS, was tested by seven different indexes and active tectonic rate was measured. Farsan and Hafshijan basin with 32.5-32.9 latitude in north hemisphere, and 50.33-50.78 longitude.By is located in Chahar Mahal and Bakhtiari provincePaying attention to paleosizemology situation on the zone and comparing it with field observation, the results have been evaluated.Materials and Methods: All the indexes have been measured with high resolution DEM (10 meters) within GIS software. Finally, the results of the active tectonic indexes were converted to IAT INDEX and the active tectonic rate map of FARSAN BASIN has prepared. The aims of this study are as follows: First, to study the tectonic status of the FARSAN BASIN along the Zagros fault margin based on active tectonic indexes.Second, to show the status of this zone by comparing the results from the active tectonic indexes at both sides of this fault and at the structural zone, i.e. SANANDAJ-SIRJAN and HIGH-ZAGROS Third, to show that which index gives better and more reliable results, considering the geomorphologic and field observations.It should be noted here that measurements have been done by GIS software using digital elevation models (DEM) with 10 -meter-pixel resolution.For studying this basin, it was divided to 30 sub-basins.Sub-basins 1-16 and 30 were located inside high Zagros zone, and 17-29 inside SANANDAJ-SIRJAN zone. These sub-basins had also been categorized into 3 classes (1, 2, and 3) based on their tectonic activity. Class 1 has the highest activity and class 3 has the lowest.Results and Discussion: Shape-ratio Index (Bl): This index is calculated by dividing length of the basin (B) by greatest width of the basin (L), B1=B/L. Based on this index, the results showed that 27.88% of basins are in class 1, out of which 15.38% are in SANANDAJ-SIRJAN zone and 12.5% in high Zagros zone.Drainage Basin ASymmetry Index (Af): This index shows the tilting caused by tectonics and is calculated by Af= 100 (Ar/At), Ar: the area at the right side of the channel, At: the total area if the basin. The results showed that 71.93% of the basins have a tilted shape and are in class 1 out of which 30.76% are in SANANDAJ-SIRJAN zone and 41.17% in high Zagros zone.Hypsometric Integral Index (Hi): It is calculated by, in which, Hmax, and Hmin are the average, maximum, and minimum height of the basin, respectively. According to the results, totally 27.14% of the basins have active tectonics and are in class 1, out of which 15.38% are in SANANDAJ-SIRJAN zone and 11.76% in high Zagros zone.Mountain-front sinuosity Index (Smf): This index is calculated by the direct distance (Lmf) divided by indirect distance (Ls), Smf=Lmf/Ls. The results based on this index showed that 77.7% of the mountain fronts are in high Zagros zone and 63.6% of them in SANANDAJ-SIRJAN zone, both of them in class 1.Ratio of Valley-floor Width to Valley Height Index (Vf): This index is calculated byVf= 2VFW/ [(ELD-ESC)+(ERD-ESC)], VFW: Valley-floor width, ESC: Valley-floor height, ERD, LD: Elevations of right and left valley divides. Based on this index, narrow and deep valleys have active tectonics. The results showed that only 37% of the measured valleys in high Zagros are in class 1 and no valley from SANANDAJ-SIRJAN zone is in class 1.Stream length-Gradiant Index (SL): it is calculated by SL= (DH/D L) L, in which DH is change in elevation of the reach; DL is length of the reach, L is the total channel length. According to the results, 23.52% of the streams are in high Zagros zone (class 1) and 15.3% are in SANANDAJ-SIRJAN zone (class 1).To produce the IAT INDEX, the authors have added all the results from these 6 indexes, calculated S/n, and finally drawn the zoning map of the FARSAN BASIN in 4 classes. The results showed that 3.18% of total basin areas (5.85 km2) have active tectonics.Conclusion: The average basin area categorized in class 1 is around 13 km2, while the average area of inactive basins is around 37.27 km2.The average height of the basins in class 1 is about2650 m., while that of in class 3 is around 2470 m. So, in this basin the MAIN ZAGROS FAULT has very active tectonics along 8350 meters and tectonically HIGH-ZAGROS zone is more active than the SANANDAJ-SIRJAN zone.

Cites

References

No record.

Cite

APA: Copy

SEIF, A., & KHOSRAVI, GH.. (2011). INVESTIGATION OF ACTIVE TECTONICS IN ZAGROS TRUSTH BELT FARSAN REGION. PHYSICAL GEOGRAPHY RESEARCH QUARTERLY, -(74), 125-146. SID. https://sid.ir/paper/138857/en

Vancouver: Copy

SEIF A., KHOSRAVI GH.. INVESTIGATION OF ACTIVE TECTONICS IN ZAGROS TRUSTH BELT FARSAN REGION. PHYSICAL GEOGRAPHY RESEARCH QUARTERLY[Internet]. 2011;-(74):125-146. Available from: https://sid.ir/paper/138857/en

IEEE: Copy

A. SEIF, and GH. KHOSRAVI, “INVESTIGATION OF ACTIVE TECTONICS IN ZAGROS TRUSTH BELT FARSAN REGION,” PHYSICAL GEOGRAPHY RESEARCH QUARTERLY, vol. -, no. 74, pp. 125–146, 2011, [Online]. Available: https://sid.ir/paper/138857/en

Related Journal Papers