Magmatic rocks and depositional setting of associated volcaniclastic strata along a north‐south traverse spanning the southern Tien Shan and eastern Pamirs of Kyrgyzstan and Tajikistan constrain the tectonics of the Pamirs and Tibet. The northern Pamirs and northwestern Tibet contain the north facing Kunlun suture, the south facing Jinsha suture, and the intervening Carboniferous to Triassic Karakul–Mazar subduction accretion system; the latter is correlated with the Songpan‐Garze–Hoh Xi system of Tibet. The Kunlun arc is a composite early Paleozoic to late Paleozoic‐Triassic arc. Arc formation in the Pamirs is characterized by ∼370–320 Ma volcanism that probably continued until the Triassic. The cryptic Tanymas suture of the southern northern Pamirs is part of the Jinsha suture. A massive ∼≤227 Ma batholith stitches the Karakul–Mazar complex in the Pamirs. There are striking similarities between the Qiangtang block in the Pamirs and Tibet. Like Tibet, the regional structure of the Pamirs is an anticlinorium that includes the Muskol and Sares domes. Like Tibet, the metamorphic rocks in these domes are equivalents to the Karakul–Mazar–Songpan‐Garze system. Granitoids intruding the Qiangtang block yield ∼200–230 Ma ages in the Pamirs and in central Tibet. The stratigraphy of the eastern Pshart area in the Pamirs is similar to the Bangong‐Nujiang suture zone in the Amdo region of eastern central Tibet, but a Triassic ocean basin sequence is preserved in the Pamirs. Arc‐type granitoids that intruded into the eastern Pshart oceanic‐basin–arc sequence (∼190–160 Ma) and granitoids that cut the southern Qiangtang block (∼170–160 Ma) constitute the Rushan‐Pshart arc. Cretaceous plutons that intruded the central and southern Pamirs record a long‐lasting magmatic history. Their zircons and those from late Miocene xenoliths show that the most distinct magmatic events were Cambro‐Ordovician (∼410–575 Ma), Triassic (∼210–250 Ma; likely due to subduction along the Jinsha suture), Middle Jurassic (∼147–195 Ma; subduction along Rushan‐Pshart suture), and mainly Cretaceous. Middle and Late Cretaceous magmatism may reflect arc activity in Asia prior to the accretion of the Karakoram block and flat‐slab subduction along the Shyok suture north of the Kohistan‐Ladakh arc, respectively. Before India and Asia collided, the Pamir region from the Indus‐Yarlung to the Jinsha suture was an Andean‐style plate margin. Our analysis suggests a relatively simple crustal structure for the Pamirs and Tibet. From the Kunlun arc in the north to the southern Qiangtang block in the south the Pamirs and Tibet likely have a dominantly sedimentary crust, characterized by Karakul–Mazar–Songpan‐Garze accretionary wedge rocks. The crust south of the southern Qiangtang block is likely of granodioritic composition, reflecting long‐lived subduction, arc formation, and Cretaceous‐Cenozoic underthrusting.

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.

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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Active deformation in the eastern Pamir of CentralAsia is concentrated on the margins of the orogen with minor deformation within the high terrain. Along the Trans-Alai mountain front at the northern perimeter of the orogen, Quaternary thrusting is documented by uplifted pediments, now at >500 m above the piedmont, Holocene fault scarps, and large earthquakes with N to NW oriented P axes. Seismicity in the interior of the orogen outlines a N-S belt that includes normal faulting events with E-W oriented T axes. N-S striking, active normal faults in the interiorLake Karakul region are compatible with these earthquakes; they define an asymmetric graben with a master fault at the western basin margin. In the southern Pamirs, dextral strike-slip faults root in the dextral Karakorum Fault, which bounds the Pamirs to the east. A mixture of dextral and reverse offsets totalling 135 m in Pleistocene terraces and 8 m in late Pleistocene/Holocene deposits demonstrates contemporary transpression, indicating average displacement rates of <1 mm/yr. The concentration of young thrusts along the Trans-Alai, the northward migration of thrusting, and the scarcity of other large-scale shortening features within the eastern Pamirs suggest that this part of the orogen moves northward en bloc and causes the progressive annihilation of the intermontane Alai Valley. Widespread dextral shear in the eastern Pamirs, both to the south and north of the extensional Karakul depression, and combined dextral strike-slip and normal faulting in the Muji-Tashgorgan graben of the Chinese Pamirs are interpreted as localized space accommodation phenomena, formed during progressive transfer of compressional deformation along a dextral strikeslip deformation zone with extensional stepovers.