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.

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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

The central Taupo Volcanic Zone in New Zealand is a region of intense Quaternary silicic volcanism accompanying rapid extension of continental crust. At least 34 caldera-forming ignimbrite eruptions have produced a complex sequence of relatively short-lived, nested, and/or overlapping volcanic centers over 1.6 m.y. Silicic volcanism at Taupo is similar to the Yellowstone system in size, longevity, thermal flux, and magma output rate. However, Taupo contrasts with Yellowstone in the exceptionally high frequency, but small size, of caldera-forming eruptions. This contrast reflects the thin, rifted nature of the crust, which precludes the development of long-term magmatic cycles at Taupo.