Using magnetic susceptibility measurements to differentiate soil drainage classes in central Iran     

Gholamzadeh  Majid  Ayoubi  Shamsollah  Shahrivar  Fatemeh Sheikhi 《Studia Geophysica et Geodaetica》2019,63(3):465-484

Studia Geophysica et Geodaetica - We examine the potential of magnetic susceptibility measurements to discriminate different soil drainage classes in the Gandoman region, central Iran. Four soil...  相似文献   

Coda <Emphasis Type="Italic">Q</Emphasis> in Qeshm Island,south of Iran,using aftershocks of the Qeshm earthquake of November 27, 2005     

Habib Rahimi  Abbas Gholamzadeh 《Arabian Journal of Geosciences》2017,10(11):239

Coda wave attenuation is estimated for Qeshm Island which is located in the southeastern part of Zagros. For this purpose, the aftershocks of Qeshm earthquake in November 27, 2005, recorded within an epicentral distance less than 100 km, have been used. More than 829 earthquakes were recorded by a local temporary network consisting of 16 short period stations installed after a week after the main shock for ～10 weeks. The coda quality factor, Q _c, was estimated using the single-backscattering model in frequency bands of 0.5–24 Hz. In this research, lateral and vertical variations of coda Q in Qeshm Island are explored. In Qeshm Island, absence of significant lateral variation of coda Q is observed. To investigate the attenuation variation with depth, the coda Q value was calculated for coda time windows with different lengths (5, 10, 15, 20, 25, and 30 s). It is observed that coda Q increases with depth. However, in our study area, the rate of increase of coda Q with depth is not uniform. Beneath Qeshm Island, the rate of increase of coda Q is greater at depths less than ～40 km compared with those of larger depths. This is indicating the existence of a low attenuation anomalous structure under the ～40-km depth which may be correlated with the Moho depth in this region. The average frequency relation for this region is Q _c = 36 ± 1.2f ^{0.94 ± 0.039} at a 5 s-lapse time window length and Q _c = 110 ± 1.8f ^{0.88 ± 0.09} at a 30-s lapse time window length.  相似文献   

The February 28, 2006 Tiab earthquake, M_w 6.0: Implications for tectonics of the transition between the Zagros continental collision and the Makran subduction zone     

A. Gholamzadeh  F. Yamini-Fard  K. Hessami  M. Tatar 《Journal of Geodynamics》2009,47(5):280-287

The 28 February, 2006 Tiab earthquake (M_w 6.0), is the first earthquake to have occurred in the transition zone between the Zagros continental collision and the Makran subduction zone for which the aftershock sequence is recorded by a temporary local seismic network. The epicentral distribution of the aftershocks is diffuse and we cannot define a simple alignment at the surface. The depth of the aftershocks increases gently northward and they are primarily concentrated between 15 and 21 km depth, implying a deeper seismogenic layer than the Zagros. Very low-angle thrust faulting deduced from this local study supports thrusting of the Arabian plate beneath central Iran at the southeastern end of the Zagros as suggested previously based on teleseismic data. The focal mechanism of the main shock indicates a thrust mechanism similar to that of other strong earthquakes in this region, while most of the focal mechanisms of the aftershocks are dominantly strike-slip. We propose that the strike-slip mechanisms belong to right-lateral fault systems that accommodate differential motion at the transition between the Zagros collision zone and the Makran subduction zone. If so, this suggests that the convergence between Arabia and central Iran is at present accommodated along the transition zone by a partitioning process.  相似文献