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[1] Two end-member kinematic models of crustal shortening across the Himalaya are currently debated: one assumes localized thrusting along a single major thrust fault, the Main Himalayan Thrust (MHT) with nonuniform underplating due to duplexing, and the other advocates for out-of-sequence (OOS) thrusting in addition to thrusting along the MHT and underplating. We assess these two models based on the modeling of thermochronological, thermometric, and thermobarometric data from the central Nepal Himalaya. We complement a data set compiled from the literature with 114 40 Ar/ 39 Ar, 10 apatite fission track, and 5 zircon (U-Th)/He thermochronological data. The data are predicted using a thermokinematic model (PECUBE), and the model parameters are constrained using an inverse approach based on the Neighborhood Algorithm. The model parameters include geometric characteristics as well as overthrusting rates, radiogenic heat production in the High Himalayan Crystalline (HHC) sequence, the age of initiation of the duplex or of out-of-sequence thrusting. Both models can provide a satisfactory fit to the inverted data. However, the model with out-of-sequence thrusting implies an unrealistic convergence rate ≥30 mm yr −1 . The out-of-sequence thrust model can be adjusted to fit the convergence rate and the thermochronological data if the Main Central Thrust zone is assigned a constant geometry and a dip angle of about 30°and a slip rate of <1 mm yr −1 . In the duplex model, the 20 mm yr −1 convergence rate is partitioned between an overthrusting rate of 5.8 ± 1.4 mm yr −1 and an underthrusting rate of 14.2 ± 1.8 mm yr −1. Modern rock uplift rates are estimated to increase from about 0.9 ± 0.31 mm yr −1 in the Lesser Himalaya to 3.0 ± 0.9 mm yr −1 at the front of the high range, 86 ± 13 km from the Main Frontal Thrust. The effective friction coefficient is estimated to be 0.07 or smaller, and the radiogenic heat production of HHC units is estimated to be 2.2 ± 0.1 mW m −3. The midcrustal duplex initiated at 9.8 ± 1.7 Ma, leading to an increase of uplift rate at front of the High Himalaya from 0.9 ± 0.31 to 3.05 ± 0.9 mm yr −1 . We also run 3-D models by coupling PECUBE with a landscape evolution model (CASCADE). This modeling shows that the effect of the evolving topography can explain a fraction of the scatter observed in the data but not all of it, suggesting that lateral variations of the kinematics of crustal deformation and exhumation are likely. It has been argued that the steep physiographic transition at the foot of the Greater Himalayan Sequence indicates OOS thrusting, but our results demonstrate that the best fit duplex model derived from the thermochronological and thermobarometric data reproduces the present morphology of the Nepal Himalaya equally well.

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Metamorphic core complexes in the D'Entrecasteaux Islands, Papua New Guinea, formed as the result of active extension at the western end of the propagating Woodlark Basin spreading center. Domes of high-grade metamorphic rocks (i.e., amphibolites, eclogites, and migmatites), intruded by large granodiorite bodies, comprise the lower plate of the D'Entrecasteaux metamorphic core complexes. The domes are transected by kilometer-scale shear zones. A thermochronologic study of the D'Entrecasteaux Islands utilizing K/Ar, 40Ar/39Ar, and fission track techniques has documented the unroofing history of these active metamorphic core complexes. Gneisses in the cores of the domes cooled rapidly (>100øC/m.y.) as indicated by hornblende and biotite 40Ar/39Ar apparent ages of-2.7 to 3.0 Ma and -1.6 to 1.7 Ma, respectively, and apatite fission track ages of-0.4 to 0.9 Ma. 40Ar/39Ar apparent ages on white mica, biotite, and potassium feldspar and fission track ages on apatites from shear zone gneisses indicate extremely rapid cooling (in some cases >500øC/m.y.) and suggest shear zones were active from 4.0 to 3.5 Ma and 1.9 to 1.4 Ma. In general, 40Ar/39Ar mineral ages for retrogressed core zone gneisses, shear zone gneisses, and granodiorites are 2.0 to 3.0 Ma (amphiboles), 1.5 to 1.7 Ma (muscovites), and 1.4 to 1.8 Ma (biotites) and 1.0 to 2.0 Ma (K-feldspars). Apatite fission track ages from core zone gneisses, shear zone gneisses and granodiorites range from 0.4 to 1.0 Ma. Thermochronologic results indicate that emplacement of granodiorites closely coincided with retrogression of the metamorphic basement and movement on the outer shear zones bounding the gneiss domes. The granodiorite bodies associated with the D•Entrecasteaux Islands domes represent syn-kinematically emplaced granitoids intruded into

The taxonomic origin of the white shark, Carcharodon, is a highly debated subject. New fossil evidence presented in this study suggests that the genus is derived from the broad‐toothed ‘mako’, Carcharodon (Cosmopolitodus) hastalis, and includes the new species C. hubbelli sp. nov. – a taxon that demonstrates a transition between C. hastalis and Carcharodon carcharias. Specimens from the Pisco Formation clearly demonstrate an evolutionary mosaic of characters of both recent C. carcharias and fossil C. hastalis. Characters diagnostic to C. carcharias include the presence tooth serrations and a symmetrical first upper anterior tooth that is the largest in the tooth row, while those indicative of C. hastalis include a mesially slanted third anterior (intermediate) tooth. We also provide a recalibration of critical fossil horizons within the Pisco Formation, Peru using zircon U‐Pb dating and strontium‐ratio isotopic analysis. The recalibration of the absolute dates suggests that Carcharodon hubbelli sp. nov. is Late Miocene (6–8 Ma) in age. This research revises and elucidates lamnid shark evolution based on the calibration of the Neogene Pisco Formation.