Boroujerd area has located in the border zone of Zagros mountain and Sanandaj-Sirjan belt in the southwest Iran. Six geomorphic indices were calculated in the study area. Through averaging these indices we obtain inde...Boroujerd area has located in the border zone of Zagros mountain and Sanandaj-Sirjan belt in the southwest Iran. Six geomorphic indices were calculated in the study area. Through averaging these indices we obtain index of active tectonics (Iat). The values of the index were divided into classes to define the degree of active tectonics. Therefore, relative tectonic activity was calculated and their values were classified and analyzed in two groups. Regions were identified as low and moderate levels. In analyzing data and combining them with tectonic setting the results were often associated and justified with regional geology. Our results show that the highest value has located along faulted area, which shows 3 classes of relative tectonic activity (moderate level). Also, other values have located along folded area (low level). Therefore, middle part of study area (sub-basin No. 4) is showing the more active uplifting related to surroundings region (sub-basin No. 1, 2 and 3). In other words, sub-basin No. 4 has got the more active uplifting by quaternary movements of several faults such as Doroud fault.展开更多
The Boroujerd pluton (ca 175 Ma) was emplaced in the Sanandaj-Sirjan zone (SSZ) active margin of Central Iran consists of monzogranite, granodiorite, and quartz-diorite. Microstructural studies show a continuum from m...The Boroujerd pluton (ca 175 Ma) was emplaced in the Sanandaj-Sirjan zone (SSZ) active margin of Central Iran consists of monzogranite, granodiorite, and quartz-diorite. Microstructural studies show a continuum from magmatic to (sub) mylonitic deformations fabric. Intensity of deformation decreases from W-NW to E-SE. The over- all magnetic fabric of the pluton yields steep NW- SE striking foliations and sub-horizontal lineations plunging both to the northwest and south- east. These features imply that during intrusion of the pluton, a NW-SE trending stretching was dominant. This stretching is ascribed to the trans- pressive deformation of the overriding SSZ during northeastward subduction of the Neotethys under the Iranian plate. The NW-SE trending lineations of the Gousheh pluton (ca 35 Ma) suggest that the transpressive regime was ongoing from the Mesozoic to late Eocene.展开更多
文摘Boroujerd area has located in the border zone of Zagros mountain and Sanandaj-Sirjan belt in the southwest Iran. Six geomorphic indices were calculated in the study area. Through averaging these indices we obtain index of active tectonics (Iat). The values of the index were divided into classes to define the degree of active tectonics. Therefore, relative tectonic activity was calculated and their values were classified and analyzed in two groups. Regions were identified as low and moderate levels. In analyzing data and combining them with tectonic setting the results were often associated and justified with regional geology. Our results show that the highest value has located along faulted area, which shows 3 classes of relative tectonic activity (moderate level). Also, other values have located along folded area (low level). Therefore, middle part of study area (sub-basin No. 4) is showing the more active uplifting related to surroundings region (sub-basin No. 1, 2 and 3). In other words, sub-basin No. 4 has got the more active uplifting by quaternary movements of several faults such as Doroud fault.
文摘The Boroujerd pluton (ca 175 Ma) was emplaced in the Sanandaj-Sirjan zone (SSZ) active margin of Central Iran consists of monzogranite, granodiorite, and quartz-diorite. Microstructural studies show a continuum from magmatic to (sub) mylonitic deformations fabric. Intensity of deformation decreases from W-NW to E-SE. The over- all magnetic fabric of the pluton yields steep NW- SE striking foliations and sub-horizontal lineations plunging both to the northwest and south- east. These features imply that during intrusion of the pluton, a NW-SE trending stretching was dominant. This stretching is ascribed to the trans- pressive deformation of the overriding SSZ during northeastward subduction of the Neotethys under the Iranian plate. The NW-SE trending lineations of the Gousheh pluton (ca 35 Ma) suggest that the transpressive regime was ongoing from the Mesozoic to late Eocene.
