Age,geochemistry, and emplacement of the ~40-Ma Baneh granite–appinite complex in a transpressional tectonic regime,Zagros suture zone,northwest Iran

The Baneh plutonic complex is situated in the Zagros suture zone of northwest Iran between the Arabian and Eurasian plates. This complex is divided into granite and appinite groups. Zircon U–Pb dating shows that granites crystallized 41–38 million years ago but appinites experience more protracted magmatic evolution, from at 52 to 38 Ma. Whole-rock chemical compositions show significant major and trace element variations between the two lithologies. Granitic rocks are more evolved, with high contents of SiO₂ (62.4–77.0 wt%), low contents of TiO₂ (0.25 wt%), MgO (0.05–1.57 wt%), and Fe₂O₃ (0.40–4.06 wt%) and high contents of Na₂O + K₂O (≈10 wt%). In contrast, appinites have low contents of SiO₂ (51.0–57.0 wt%) and K₂O (<2.1 wt%) and high Fe₂O₃ (6.4–9.35 wt%), MgO (2.0–9.9 wt%), and Mg number (Mg# = 35–76). The concentration of rare earth elements in the appinites is higher than in granitic rocks, making it difficult to form granites solely by fractionation of appinite magma. (⁸⁷Sr/⁸⁶Sr)_i and ε_Nd(40 Ma) in both groups are similar, from 0.7045 to 0.7061 and ?1.2 to +2.6, except for a primitive gabbroic dike with ε_Nd(40 Ma) = +9.9. Appinites show mainly typical I-type characteristics, but granites have some S-type characteristics. The sigmoidal shape of the Baneh pluton and its emplacement into deformed Cretaceous shales and limestone showing kink bands, asymmetric and recumbent folds in a broad contact zone, with pervasive ductile to brittle structures in both host rocks and intrusion, indicate that magma emplacement was controlled by a transpressional tectonic regime, perhaps developed during early stages in the collision of Arabia and Eurasian plates.     

The effect of relative density on the response of sand to internal fluidization

Acta Geotechnica - Fluidization, in the geotechnical engineering context, is a failure mechanism that can occur during piping, leakage in distribution pipes or leakage through the sheet pile walls...     

Iranian earthquakes, a uniform catalog with moment magnitudes

A uniform earthquake catalog is an essential tool in any seismic hazard analysis. In this study, an earthquake catalog of Iran and adjacent areas was compiled, using international and national databanks. The following priorities were applied in selecting magnitude and earthquake location: (a) local catalogs were given higher priority for establishing the location of an earthquake and (b) global catalogs were preferred for determining earthquake magnitudes. Earthquakes that have occurred within the bounds between 23–42° N and 42–65° E, with a magnitude range of M _W 3.5–7.9, from the third millennium BC until April 2010 were included. In an effort to avoid the “boundary effect,” since the newly compiled catalog will be mainly used for seismic hazard assessment, the study area includes the areas adjacent to Iran. The standardization of the catalog in terms of magnitude was achieved by the conversion of all types of magnitude into moment magnitude, M _W, by using the orthogonal regression technique. In the newly compiled catalog, all aftershocks were detected, based on the procedure described by Gardner and Knopoff (Bull Seismol Soc Am 64:1363–1367, 1974). The seismicity parameters were calculated for the six main tectonic seismic zones of Iran, i.e., the Zagros Mountain Range, the Alborz Mountain Range, Central Iran, Kope Dagh, Azerbaijan, and Makran.     

Designing an integrated urban growth prediction model: a scenario-based approach for preserving scenic landscapes

Abstract

This study demonstrates the integration of landscape aesthetic quality and probable urban growth patterns in urban landscape modelling. This was performed using SLEUTH as a scenario-based urban growth model in Gorgan City of Iran. Future urbanization was predicted under developing three different scenarios including historical, managed and aesthetically sound urban growth up to the year 2030. Multi-Layer Perceptron neural network model was conducted for mapping the aesthetic suitability of the study area. The aesthetic suitability layer was used in the third scenario of SLEUTH model as the excluded layer to protect the scenic patches in future. The results showed that by correct implementation of urban growth policies, 323 ha in the second scenario and 650 ha in the third scenario would be saved. This integrated model would help the planners for a better management of urban landscapes as a Spatial Decision Support System.