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Summary. Over 80 new fault plane solutions, combined with satellite imagery as well as both modern and historical observations of earthquake faulting, are used to investigate the active tectonics of the Middle East between western Turkey and Pakistan. The deformation of the western part of this region is dominated by the movement of continental material laterally away from the Lake Van region in eastern Turkey. This movement helps to avoid crustal thickening in the Van region, and allows some of the shortening between Arabia and Eurasia to be taken up by the thrusting of continental material over oceanic‐type basement in the southern Caspian, Mediterranean, Makran and Black Sea. Thus central Turkey, bounded by the North and East Anatolian strike‐slip faults, is moving west from the Van region and overrides the eastern Mediterranean at two intermediate depth seismic zones: one extending between Antalya Bay and southern Cyprus, and the other further west in the Hellenic Trench. The motion of northern Iran eastwards from the Van region is achieved mainly by a conjugate system of strike‐slip faults and leads to the low angle thrusting of Iran over the southern Caspian Sea. The seismicity of the Caucasus shows predominantly shortening perpendicular to the regional strike, but there is also some minor elongation along the strike of the belt as the Causcasus overrides the Caspian and Black Seas. The deformation of the eastern part of this region is dominated by the shortening of Iran against the stable borders of Turkmenistan and Afghanistan. The north‐east direction of compression seen in Zagros is also seen in north‐east Iran and the Kopet Dag, where the shortening is taken up by a combination of strike‐slip and thrust faulting. Large structural as well as palaeomagnetic rotations are likely to have occurred in NE Iran as a result of this style of deformation. North‐south strike‐slip faults in southern Iran allow some movement of material away from the collision zone in NE Iran towards the Makran subduction zone, where genuinely intermediate depth seismicity is seen. Within this broad deforming belt large areas, such as central Turkey, NW Iran (Azerbaijan), central Iran and the southern Caspian, appear to be almost aseismic and therefore to behave as relatively rigid blocks surrounded by active belts 200‐300 km wide. The motion of these blocks can usefully be described by poles of rotation. The poles presented in this paper predict motions consistent with those observed and also predict the opening of the Gulf of Iskenderun NE of Cyprus, the change within the Zagros mountains from strike‐slip faulting in the NW to intense thrusting in the SE, and the relatively feeble seismicity in SE Iran (Baluchistan). This description also explains why the north‐south structures along the Iran‐Afghanistan border do not cut the east‐west ranges of the Makran. Within the active belts surrounding the relatively aseismic blocks a continuum approach is needed for a description of the deformation, even though motions at the surface may b...

S U M M A R Y In this paper we examine the connection between the westward motion of Turkey relative to Europe and the extension in and around the Aegean Sea. The principal new data available since the last attempt to synthesize the tectonics of this region by McKenzie (1978) are much improved focal mechanisms of earthquakes, constrained by P and SH body wave modelling as well as by first motions. These mechanisms show that the faulting in the western part of the Aegean region is mostly extensional in nature, on normal faults with a NW to WNW strike and with slip vectors directed NNW to NNE. There is evidence from palaeomagnetism that this western region rotates clockwise relative to stable Europe. In the central and eastern Aegean, and in NW Turkey, distributed right-lateral strike-slip is more prevalent, on faults trending NE to ENE, and with slip vectors directed NE. Palaeomagnetic data in this eastern region is more ambiguous, but consistent with very small or no rotations in the northern part and possibly anticlockwise rotations, relative to Europe, in the south. The strike-slip faulting that enters the central Aegean from the east appears to end abruptly in the SW against the NW-trending normal faults of Greece.The kinematics of the deformation is controlled by three factors: the westward motion of Turkey relative to Europe; the continental collision between NW Greece-Albania and the Apulia-Adriatic platform in the west; and the presence of the Hellenic subduction zone to the south. As the right-lateral slip on the North Anatolian Fault enters the Aegean region it splays out, becoming distributed on several parallel faults. The continental shortening in NW Greece and Albania does not allow the rotation of the western margin of the region to be rapid enough to accommodate this distributed E-W right-lateral shear, and thus leads to E-W shortening in the northern Aegean, which is compensated by N-S extension as the southern Aegean margin can move easily over the Hellenic subduction zone. The dynamics of the system, once initiated, is self-sustaining, being driven by the high topography in eastern Turkey and by the roll-back of the subducted slab beneath the southern Aegean.The geometry of the deformation resembles the behaviour of a system of broken slats attached to margins that rotate. In spite of its extreme simplicity, a simple model of such broken slats is able to reproduce quantitatively most of the features of the instantaneous velocity field in the Aegean region, including: the slip vectors and nature of the faulting in the eastern and western parts; the senses and approximate rates of rotation; the overall extensional velocity across the Aegean; and the distribution of strain rates, as seen in the seismicity and topography or bathymetry, and using geodetic measurements.As part of this study, we re-examined the relation between the surface faulting and the focal parameters determined seismologically for the three large 1981 Gulf of Corinth earthquakes, and reassessed the evidence for associating partic...

This paper is concerned with the relationship between the overall motion across a zone of distributed continental deformation and the seismic moment tensors of earthquakes that occur within it. The overall deformation in the zone is described by the deformation gradient tensor L, which may be split into a symmetric part, S, and an antisymmetric part, A. S is the strain tensor, and can always be determined from the sum of the moment tensors, following the result of Kostrov (1974). A corresponds to a rigid body rotation, and is in principle unobservable seismically: the moment tensors contain no information about A, regardless of whether the ambiguity between fault and auxiliary planes is resolved. From S the integrated rates of motion normal and parallel to the zone boundary, as well as vertically, can be calculated. Of these, only the motion normal to the zone is specified by the motion across its boundaries. In general, S (and hence L) is not specified by the motion of the plates bounding the zone. Only if some a priori assumptions about L are made, can information about A be recovered from the seismic moment tensors. Otherwise

Angiogenesis is a critical component of the proliferative endometrial phase of the menstrual cycle. Thus, we hypothesized that a stem cell-like population exist and can be isolated from menstrual blood. Mononuclear cells collected from the menstrual blood contained a subpopulation of adherent cells which could be maintained in tissue culture for >68 doublings and retained expression of the markers CD9, CD29, CD41a, CD44, CD59, CD73, CD90 and CD105, without karyotypic abnormalities. Proliferative rate of the cells was significantly higher than control umbilical cord derived mesenchymal stem cells, with doubling occurring every 19.4 hours. These cells, which we termed "Endometrial Regenerative Cells" (ERC) were capable of differentiating into 9 lineages: cardiomyocytic, respiratory epithelial, neurocytic, myocytic, endothelial, pancreatic, hepatic, adipocytic, and osteogenic. Additionally, ERC produced MMP3, MMP10, GM-CSF, angiopoietin-2 and PDGF-BB at 10-100,000 fold higher levels than two control cord blood derived mesenchymal stem cell lines. Given the ease of extraction and pluripotency of this cell population, we propose ERC as a novel alternative to current stem cells sources.

Seismicity and fault‐plane solutions show that the active deformation in the Adriatic region is very varied. West of Messina, N–S shortening occurs with slip vectors representative of the overall Africa–Eurasia motion. Along the length of peninsular Italy, NE–SW extension on normal faults is the dominant style of deformation, but changes to N–S shortening in N. Italy. Inland central and northern Yugoslavia is deforming on strike‐slip and thrust faults, and an intense belt of NE–SW shortening continues south along the coast from central Yugoslavia into Albania. South of Albania the shortening in coastal regions is in a more easterly direction. The most remarkable feature of the region is the low level of seismicity in the Adriatic Sea itself, compared with the intense activity in the high topographic belts that border it on the SW, NW and NE. The relatively rigid behaviour of the Adriatic allows its motion relative to Eurasia to be described by rotation about a pole in N. Italy. Anticlockwise rotation about this pole accounts, in a general way, for the change in style and orientation of the deformation in the circum‐Adriatic belts. Historical and recent seismicity account for approximately equal rates of extension in central Italy and shortening in southern Yugoslavia of about 2 mm yr−1; however, these are uncertain by at least a factor of two, and are anyway likely to be underestimates of the true motion, because of the unknown contribution of aseismic creep. The Adriatic region resembles, in some ways, other relatively stable continental blocks, such as Central Iran and the Tarim Basin, that are caught up within the distributed deformation of the Alpine–Himalayan Belt. The Adriatic, however, is bounded on three sides by the relatively stable Eurasia plate. Its boundary with the African plate is short and ill‐defined by seismicity, but is likely to be located in the Southern Adriatic, near the Strait of Otranto. The present day seismicity shows that the Adriatic, although once perhaps ‘a promontory of Africa', is no longer behaving in this way, and the motions on its boundaries do not directly reflect the Africa–Eurasia convergence.

S U M M A R YThe Zagros mountains of SW Iran are one of the most seismically active intra-continental fold-and-thrust belts on Earth, and an important element in the active tectonics of the Middle East. Surface faulting associated with earthquakes is extremely rare, and so most information about the active faulting comes from earthquakes. We use long-period teleseismic P and SH body waves to determine the orientation and depth of faulting in 16 new earthquakes, and then evaluate and synthesize all the available teleseismic data on earthquake source parameters in the Zagros. We use this information to investigate the style and distribution of active faulting in the Zagros, and how it contributes to the N-S shortening of the Arabia-Eurasia collision. When the data are ranked in quality and carefully evaluated, simple patterns are seen that are not apparent when routine catalogue data are taken at face value. An important change in the fault configuration occurs along strike of the belt. In the NW, overall convergence is oblique to the trend of the belt and the surface anticlines, and is achieved by a spatial separation ('partitioning') of the orthogonal strike-slip and shortening components on separate parallel fault systems. By contrast, in the SE, overall convergence is orthogonal to the regional strike and achieved purely by thrusting. In the central Zagros, between these two structural regimes, deformation involves parallel strike-slip faults that rotate about vertical axes, allowing extension along the strike of the belt. The overall configuration is similar to that seen in other curved shortening belts, such as the Himalaya and the Java-Sumatra trench. All the Zagros earthquakes we have been able to check have centroids shallower than ∼20 km and are confined to the upper crust. Many of the larger earthquakes are likely to occur in the basement beneath the sedimentary cover, which is active even beneath areas of known shallow structural decollement such as the Dezful embayment. The dominant style of shortening is high-angle reverse faulting with dips >30 • though some lower-angle thrusting occurs in places. Active thrust and reverse faulting is relatively confined to the lower topography on the SW edge of the belt today, and only strike-slip faulting affects the higher topography. Profound vertical changes in structural and stratigraphic level indicate that a similar style of deformation was once active across the width of the Simple Folded Belt, but has progressively migrated SW over the last 5 Ma. There is no evidence for a seismically active structural decollement, such as a low-angle thrust, beneath the Zagros, nor is there any seismic evidence for active subduction, either beneath the Zagros or beneath central Iran. Instead the Arabian margin seems to have shortened by distributed thickening of the basement. Only in the syntaxis of the Oman Line, at the SE end of the Zagros, is there any evidence for a low-angle thrust of regional extent. Here, earthquakes continue 50 km north of the Zagros Thrust Line (t...

The Arabia‐Eurasia collision deforms an area of ∼3,000,000 km2 of continental crust, making it one of the largest regions of convergent deformation on Earth. There are now estimates for the active slip rates, total convergence and timing of collision‐related deformation of regions from western Turkey to eastern Iran. This paper shows that extrapolating the present day slip rates of many active fault systems for ∼3–7 million years accounts for their total displacement. This result means that the present kinematics of the Arabia‐Eurasia collision are unlikely be the same as at its start, which was probably in the early Miocene (16–23 Ma) or earlier. In some, but not all, active fault systems, short‐term (∼10 year) and long‐term (∼5 million year) average deformation rates are consistent. There is little active thickening across the Turkish‐Iranian plateau and, possibly, the interior of the Greater Caucasus. These are two areas where present shortening rates would need more than 7 million years to account for the total crustal thickening, and where there are structural and/or stratigraphic data for pre‐late Miocene deformation. We suggest that once thick crust (up to 60 km) built up in the Turkish‐Iranian plateau and the Greater Caucasus, convergence took place more easily by crustal shortening in less elevated regions, such as the Zagros Simple Folded Zone, the South Caspian region and foothills of the Greater Caucasus, or in other ways, such as westward transport of Turkey between the North and East Anatolian faults. The time and duration of this changeover are not known for certain and are likely be diachronous, although deformation started or intensified in many of the currently active fault systems at ∼5 ± 2 Ma.