The late Oligocene‐Miocene tectonic style of the Alps is variable along strike of the orogen. In the Western and Central Alps, foreland imbrication, backthrusting, and backfolding dominate. In the Eastern Alps, strike‐slip and normal faults prevail. These differences are due to lateral extrusion in the Eastern Alps. Lateral extrusion encompasses tectonic escape (plane strain horizontal motion of tectonic wedges driven by forces applied to their boundaries) and extensional collapse (gravitational spreading away from a topographic high in an orogenic belt). The following factors contributed to the establishment of lateral extrusion in the Eastern Alps: (1) a rigid foreland, (2) a thick crust created by indentation and earlier collision, (3) a decrease in strength in the crust due to thermal relaxation, (4) a crustal thickness gradient from the Eastern Alps to the Carpathians, and, possibly, (5) a disturbance of the lithospheric root. Northward indentation by the Southern Alps causes thickening in and in front of the indenter and tectonic escape. Gravitational spreading attenuates crustal thickness differences. Indentation structures occur in the western Eastern Alps and comprise folds, thrusts, and strike‐slip faults. These structures pass laterally into spreading structures, which encompass transtensional and normal faults in the eastern Eastern Alps. The overall structural pattern is dominated by escape structures, namely, sets of strike‐slip faults that bound serially extruding wedges. Structural complexity arises from (1) interference of major fault sets, (2) accommodation of displacement differences between the Eastern Alps and their fore‐ and hinterland, (3) displacement transfer from the Eastern Alps toward the Carpathians which act as a lateral unconstrained margin, and (4) crustal decoupling, which partitions extrusion into brittle upper plate and ductile lower plate deformation. The kinematics of lateral extrusion is approximated by an extrusion‐spreading model proposed for nappe tectonics.

Abstract. The largest tract of ultrahigh-pressure rocks, the Dabie-Hong'an area of China, was exhumed from 125 km depth by a combination of normal-sense shear from beneath the hanging wall Sino-Korean craton, southeastward thrusting onto the footwall Yangtze craton, and orogenparallel eastward extrusion. Prior to exhumation the UHP slab extended into the mantle a downdip distance of 125-200 km at its eastern end, whereas it was subducted perhaps only 20-30 km at its far western end ~200 km away. Structural reconstructions imply that the slab was > 10 km thick. In the Hong'an area (Figures 1 and 2), blueschist-facies rocks are more widespread, and a distinct eclogite-retrogressed-toamphibolite unit has been mapped, in addition to quartz eclogite and coesite eclogite. Also, a wider variety of Paleozoic metamorphic rocks crop out in E-W trending fault-bounded units

Field and radiometric data are used to describe and date strain and stress states in southern (longitude 88° to 91°E, latitude 28° to 30°N) and western Tibet (longitude 79° to 82°E, latitude 30° to 34°N). We factorize deformation into syncollisional and postcollisional, and we present stretching lineation and displacement orientation maps, two sections across the Indian shelf sequence, and stress orientations calculated from mesoscale fault slip data. In southern Tibet, syncollisional stretching and displacement directions trend 9°±46° and displacement is top to south. Synkinematic, low‐grade metamorphism is dated at 50 Ma at one locality in the Indian shelf sequence underlying the main mantle thrust of the Indus‐Yarlung suture. This implies Paleocene onset of continental collision for the investigated section. Postcollisional structures comprise a “backthrust” group, which includes foreland‐ and hinterland‐directed thrusts, reverse and strike‐slip faults, and folds. It dominates postcollisional deformation, is concentrated along the Indus‐Yarlung suture, and portrays N‐S compression (σ1 trend of 8°±17°, σ2 of 97°±17°). A “strike‐slip” group consists of conjugate strike‐slip faults, is concentrated in east trending, narrow, highly deformed zones, and indicates that N‐S compression is locally compensated by E‐W extension (σ1 of 15°±29°, σ3 of 103°±30°). Synkinematic muscovite dates postcollisional deformation as late early Miocene (17.5 Ma) at one locality at the suture. Strike‐slip and oblique normal (σ3 of 60°±23°, σ1 of 144°±21°) and normal (σ3:114°±16°) faulting, dated between late Miocene and Recent and including active deformation, represents (dominant) E‐W and minor N‐S extension due to E‐W stretching of southern Tibet and oroclinal bending along the Himalayan arc. Restoring syncollisional and postcollisional deformation yields a minimum of 67% (258 km) shortening across the Indian shelf sequence. Incorporating recently published contraction estimates across the eastern Himalaya yields minimum shortening between undeformed India and the Indus‐Yarlung suture of 66% (536 km). The Himalaya‐Tibet orogenic system south of the Indus‐Yarlung suture had an initial width of ≥811 km in the southern Tibetan section. In western Tibet, imbrication of an ophiolite sequence of the Bangong‐Nujiang suture is top to south (stretching lineation trend of 15°±18°), and σ3 of active deformation trends ESE. Faulting along the Shiquanhe fault zone, which transfers displacement from the northern part of the Karakorum fault to a system of rifts in western central Tibet, indicates dextral strike‐slip alternating with sinistral‐oblique normal faulting and block rotations around vertical axes during a prolonged shearing history. The Indian Shelf sequence south of Mount Kailas shows top to south imbrication (stretching lineation trend of 52°±60°). Both Indian shelf rocks and (?Oligocene‐Miocene) Kailas conglomerates record backthrusting and backfolding (σ1 of 33°) and Recent E‐W extension (σ3 of 85°±28°).

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Lateral extrusion encompasses extensional collapse (gravitational spreading away from a topographic high in an orogenic belt) and tectonic escape (plane strain horizontal motion of wedges driven by forces applied to their boundaries). In the Eastern Alps it resulted from (1) an overall northerly compression (Apulia against Eurasia), (2) a strong foreland (Bohemian massif), (3) lack of constraint along a lateral boundary (Carpathian region), and (4) a previously thickened, gravitationally unstable, thermally weakened crust (Eastern Alpine orogenic belt). Si:• indentation experiments reproduce lateral extrusion at lithospheric scale. The models have two to four lithospheric layers, with a Mohr/Coulomb rheology for the upper and a viscous rheology for the lower crust. The lithosphere rests upon a low-viscosity asthenosphere. A broad indenter, a narrow deformable area, and a weakly constrained eastern margin fullfill as closely as possible conditions in the Eastern Alps. Indentation produces both thickening in front of the indenter and escape of triangular wedges. Lateral variations in crustal thickness become attenuated by gravitational spreading. The overall fault pattern includes domains of reverse, strike-slip, oblique normal, and pure normal faults. Strike-slip faults in conjugate sets develop serially. The narrow width of the deformable area and the strength of the foreland determine the angles between the sets. Gravitational spreading produces a rhombohedral pattern of oblique and pure normal faults along the unconstrained margin. Opposite the unconstrained margin, the indenter front Copyright 1991 by the American Geophysical Union. Paper number 90TC02622. 0278-7407/91/90TC-02622510.00 shows thrusts and folds intersecting with the conjugate strike-slip sets. A triangular indenter favors spreading. High velocity of indentation favors escape. High confinement limits lateral motion, inhibits spreading, and favors thickening. Lateral extrusion in the Eastern Alps is best modeled by (1) a weak lateral confinement, (2) a broad and straight indenter, (3) a narrow width of the deformable area, and (4) a rigid foreland. Crustal thickening, lateral escape, and gravitational spreading all contribute to the overall deformation.

Bell's theorem shows that local realistic theories place strong restrictions on observable correlations between different systems, giving rise to Bell's inequality which can be violated in experiments using entangled quantum states. Bell's theorem is based on the assumptions of realism, locality, and the freedom to choose between measurement settings. In experimental tests, "loopholes" arise which allow observed violations to still be explained by local realistic theories. Violating Bell's inequality while simultaneously closing all such loopholes is one of the most significant still open challenges in fundamental physics today. In this paper, we present an experiment that violates Bell's inequality while simultaneously closing the locality loophole and addressing the freedom-of-choice loophole, also closing the latter within a reasonable set of assumptions. We also explain that the locality and freedom-of-choice loopholes can be closed only within non-determinism, i.e. in the context of stochastic local realism.Comment: 12 pages, 3 figures, 2 tables, published online before print: http://www.pnas.org/content/early/2010/10/29/1002780107.abstrac

Asian deep crust exposed in the Pamir permits determination of the amount, sequence, and interaction of shortening, extension, and lateral extrusion over ~30 km of crustal section during the India‐Asia collision. In the Central Pamir, gneiss domes and their hanging walls record Paleogene tripling of the 7–10 km thick Phanerozoic upper crustal strata; total crustal thickness may have amounted to 90 km. Two thrust sheets, comprising Cambro‐Ordovician, respectively, Carboniferous to Paleogene strata, straddle the domes. Amphibolite‐facies metamorphic rocks within the domes—equivalent to lower grade rocks outside the domes—form fold nappes with dome‐scale wavelengths. E‐W stretching occurred contemporaneously with top‐to‐ ~ N imbrication and folding. At ~22–12 Ma, bivergent (top‐to‐N and top‐to‐S), normal‐sense shear zones exhumed the crystalline rocks; most of the extension occurred along the northern dome margins. Shortening resumed at ~12 Ma with opposite‐sense thrusting and folding focused along the dome margins. Throughout the building of the Central and South Pamir, dominant ~N‐S shortening interacted with ~E‐W extension along mostly dextral shear/fault zones. In the Neogene, shear is concentrated along a dextral wrench corridor south of the domes. We interpret the Paleogene shortening to record thickening and northward growth of the Pamir‐Tibetan Plateau and short‐lived Miocene crustal extension as gravitational adjustment, i.e., collapse, of the thickened Asian crust to Indian slab breakoff. Synconvergent Paleogene lateral extrusion thickened the Afghan Hindu Kush crust west of the India‐Asia collision, and the Miocene‐Recent dextral shear and ~E‐W extension have accommodated collapse of the Pamir Plateau into the Tajik depression.