On Solution and Stability of a Two-Variable Functional Equations

The main purpose of this paper is to investigate the stability of the functional equation f(x+y,y+z)=2f(x/2,y/2)+2f(y/2,z/2) in normed spaces. The solutions of such functional equations are considered

Paleoearthquakes and slip rates of the North Tabriz Fault, NW Iran: preliminary results

The North Tabriz Fault is a major seismogenic fault in NW Iran. The last damaging earthquakes on this fault occurred in 1721, rupturing the southeastern fault segment, and in 1780, rupturing the northwestern one. The understanding of the seismic behavior of this fault is critical for assessing the hazard in Tabriz, one of the major cities of Iran; the city suffered major damage in both the 1721 and 1780 events. Our study area is located on the northwestern fault segment, west of the city of Tabriz. We performed geomorphic and trenching investigations, which allowed us to recognize evidence for repeated faulting events since the Late Pleistocene. From the trenches, we found evidence for at least four events during the past 3.6 ka, the most recent one being the 1780 earthquake. On the basis of different approaches, horizontal slip per event and slip rates are found in the ranges of 4 ± 0.5 m and 3.1-6.4 mm/yr, respectively. We also attempted an estimate of the average recurrence intervals which appears to be in the range 350-1430 years, with a mean recurrence interval of 821 ± 176 years. On the basis of these results, the northwestern segment of the North Tabriz Fault does not appear to present a major seismic potential for the near future, however, not enough is known about the southeastern segment of the fault to make a comparable conclusion

Paleoearthquakes and slip rates of the North Tabriz Fault, NW Iran: preliminary results

The North Tabriz Fault is a major seismogenic fault in NW Iran. The last damaging earthquakes on this fault occurred in 1721, rupturing the southeastern fault segment, and in 1780, rupturing the northwestern one. The understanding of the seismic behavior of this fault is critical for assessing the hazard in Tabriz, one of the major cities of Iran; the city suffered major damage in both the 1721 and 1780 events. Our study area is located on the northwestern fault segment, west of the city of Tabriz. We performed geomorphic and trenching investigations, which allowed us to recognize evidence for repeated faulting events since the Late Pleistocene. From the trenches, we found evidence for at least four events during the past 3.6 ka, the most recent one being the 1780 earthquake. On the basis of different approaches, horizontal slip per event and slip rates are found in the ranges of 4 ± 0.5 m and 3.1-6.4 mm/yr, respectively. We also attempted an estimate of the average recurrence intervals which appears to be in the range 350-1430 years, with a mean recurrence interval of 821 ± 176 years. On the basis of these results, the northwestern segment of the North Tabriz Fault does not appear to present a major seismic potential for the near future, however, not enough is known about the southeastern segment of the fault to make a comparable conclusion

Utjecaj izloženosti 1,6-heksametilen diizocijanatu (HDI) na vršni ekspiratorni protok u autolakirera u Iranu

The aim of this study was to investigate the effects of occupational exposure to 1,6-hexamethylene diisocyanate (HDI) on peak flowmetry in automobile body paint shop workers in Iran. We studied a population of 43 car painters exposed to HDI at their workplaces. Peak expiratory fl ow was tested for one working week, from the start to the end of each shift. Air was sampled and HDI analysed in parallel, according to the OSHA 42 method. Daily and weekly HDI exposure averages were (0.42±0.1) mg m-3 and (0.13±0.05) mg m-3, respectively. On painting days, 72 % of workers showed more than a 10 % variation in peak expiratory fl ow. Inhalation exposure exceeded the threshold limit value (TLV) ten times over. This strongly suggests that HDI affected the peak fl owmetry in the studied workers.Cilj je ovog ispitivanja bio utvrditi vršni protok u 43 iranska autolakirera profesionalno izložena 1,6-heksametilen diizocijanatu (HDI). Vršni ekspiratorni protok testiran je tjedan dana na početku i kraju svake smjene. Uzorkovanje i mjerenje HDI-ja u zraku radilo se istodobno s testiranjem vršnoga protoka, prema metodi OSHA 42. Prosječna dnevna izloženost radnika HDI-ju iznosila je (0.42±0.1) mg m-3, a tjedna (0.13±0.05) mg m-3. U 72 % radnika vršni ekspiratorni protok tijekom dana varirao je više od 10 %. Radnici su udisali deset puta više razine HDI-ja od graničnih te je moguće da je HDI utjecao na mjerenja plućne funkcije

Tectonique active du Nord-est de l'Iran et accommodation de la convergence entre l'Arabie et l'Eurasie : contribution des chaînes du Kopeh Dagh et du Binalud

Ce travail de thèse a été effectué afin de comprendre les processus de déformation active dans le NE de l Iran, constitué des chaines de montagnes du Kopeh Dagh et du Binalud. Cet objectif a été poursuivi en combinant plusieurs approches : géologie structurale et tectonique, géomorphologie quantitative et plusieurs méthodes de datation (40Ar/39, 36Cl et 10Be). Ce travail porte sur trois secteurs clefs du NE de l Iran : le Kopeh Dagh, le Binalud et la Zone de Transfert de Meshkan. Cette étude a permis d établir les premières estimations de vitesse sur l ensemble du système de failles dans le Kopeh Dagh. La vitesse de déplacement horizontal dextre sur l ensemble du système est de 9+-2 mm/an. De l ordre de 25% de la déformation décrochante du Kopeh Dagh est transférée vers le Sud, vers le Binalud, grâce à une série de structures tectoniques définissant un domaine de déformation complexe: la Zone de Transfert de Meshkan. Sur les deux versants du Massif du Binalud, nous avons déterminé des vitesses de déplacements horizontaux de 3.6+-1.2 mm/an et 1.6+-0.1 mm/an, le long de zones de failles affectant les versants méridionaux et septentrionaux du Massif, respectivement. Ces vitesses permettent de calculer un taux de déplacement dextre long-terme et total d environ 5 mm/an. Les analyses cinématiques réalisées pendant ce travail indiquent que la convergence est accommodée par des décrochements et des chevauchements le long de structures d orientations différentes. Cet assemblage structural est impliqué dans un champ de contraintes actuel mécaniquement compatible et homogène. L homogénéité des états de contraintes déterminés n est pas en faveur d un partitionnement complet entre les failles décrochantes / inverses. Les différents types de mouvements observés sur les failles ne résultent que de l orientation des failles par rapport au champ de contraintes à l échelle régionale. L ensemble de ces observations permettent de proposer un modèle tectonique cohérant qui explique la cinématique et la déformation active du NE de l Iran.AIX-MARSEILLE3-BU Sc.St Jérô (130552102) / SudocSudocFranceF

Quaternary slip rates along the northeastern boundary of the Arabia-Eurasia collision zone (Kopeh Dagh Mountains, Northeast Iran)

International audienceP>The Kopeh Dagh is accommodating a large portion of the northward motion of central Iran with respect to Eurasia, involving a major right-lateral strike-slip fault system (Bakharden-Quchan). This fault system corresponds to the northeastern boundary of the Arabia-Eurasia collision, and can be considered as a lithospheric-scale tectonic feature. We present a well-constrained estimation of late Quaternary slip rates along two major strike-slip faults (the Baghan and Quchan faults) in this fault system, using in situ-produced Cl-36 nuclide to date two offset alluvial fan surfaces. Combining detailed satellite image and digital topographic data analyses complemented with geomorphic fieldwork allows quantifying the cumulative offset values of 940 +/- 100 and 360 +/- 50 m of the fan surfaces along the Baghan and Quchan faults, respectively. A total of 12 carbonate boulders from the fan surfaces were collected and dated. This yields minimum age of two episodes of fan abandonment at 280 +/- 16 (Baghan fault) and 83 +/- 4 ka (Quchan fault). Age estimates and measured offsets of the fans are consistent with respective maximum long-term fault slip rates of 2.8 +/- 1.0 and 4.3 +/- 0.6 mm yr(-1) for the Baghan and Quchan faults over the Middle-Late Pleistocene. Applying the slip rates to cumulative post-folding offsets along the Baghan and Quchan faults indicates that strike-slip motion within the Kopeh Dagh may have started similar to 4 Ma. This constrains the timing of a major tectonic reorganization in the Kopeh Dagh, previously recorded through Arabia-Eurasia collision between 3 and 7 Ma. At the regional scale, the sum of total cumulative strike-slip offsets is about 35-40 km, which implies a total maximum slip rate of about 9 +/- 2 mm yr(-1) in the Central-Eastern Kopeh Dagh. This is resolved to average northward and westward slip rates of similar to 8 and similar to 4 mm yr(-1), respectively, for the Western Kopeh Dagh with respect to Eurasia. Our results also suggests that the localized strike-slip faulting in the Central Kopeh Dagh can be considered as an intercontinental movement between northeast Iran and Eurasia, accommodating about 80 per cent of northward motion of central Iran with respect to Eurasia

Plio-Quaternary stress states in NE Iran: Kopeh Dagh and Allah Dagh-Binalud mountain ranges

International audienceNE Iran, including the Kopeh Dagh and Allah Dagh-Binalud deformation domains, comprises the northeastern boundary of the Arabia-Eurasia collision zone. This study focuses on the evolution of the Plio-Quaternary tectonic regimes of northeast Iran. We present evidence for drastic temporal changes in the stress state by inversion of both geologically and seismically determined fault slip vectors. The inversions of fault kinematics data reveal distinct temporal changes in states of stress during the Plio-Quaternary (since similar to 5 Ma). The paleostress state is characterized by a regional transpressional tectonic regime with a mean N140 +/- 10 degrees E trending horizontal maximum stress axis (sigma(1)). The youngest (modern) state of stress shows two distinct strike-slip and compressional tectonic regimes with a regional mean of N030 +/- 15 degrees E trending horizontal sigma(1). The change from the paleostress to modern stress states has occurred through an intermediate stress field characterized by a mean regional N trending sigma(1). The inversion analysis of earthquake focal mechanisms reveals a homogeneous, transpressional tectonic regime with a regional N023 +/- 5 degrees E trending sigma(1). The modern stress state, deduced from the youngest fault kinematics data, is in close agreement with the present-day stress state given by the inversions of earthquake focal mechanisms. According to our data and the deduced results, in northeast Iran, the Arabia-Eurasia convergence is taken up by strike-slip faulting along NE trending left-lateral and NNW trending right-lateral faults, as well as reverse to oblique-slip reverse faulting along NW trending faults. Such a structural assemblage is involved in a mechanically compatible and homogeneous modern stress field. This implies that no strain and/or stress partitioning or systematic block rotations have occurred in the Kopeh Dagh and Allah Dagh-Binalud deformation domains. The Plio-Quaternary stress changes documented in this paper call into question the extrapolation of the present-day seismic and GPS-derived deformation rates over geological time intervals encompassing tens of millions of years. (c) 2009 Elsevier B.V. All rights reserved