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Control of lithospheric inheritance on neotectonic activity in northwestern Canada?

Lithospheric inheritance is thought to affect the location and reactivation of tectonic structures through successive cycles of supercontinent formation and dispersal; however, its relation to neotectonic activity remains unclear. In...Show More Summary

Recycling in debris-filled volcanic vents

Eruptions through debris-filled vents produce deposits containing magmatic juvenile lithic and recycled clasts. Recycled clasts are exposed to multiple transportation and fragmentation events. We used experiments with multiple subsurface...Show More Summary

First terrestrial occurrence of tistarite (Ti2O3): Ultra-low oxygen fugacity in the upper mantle beneath Mount Carmel, Israel

The minimum oxygen fugacity ( f O 2 ) of Earth’s upper mantle probably is controlled by metal saturation, as defined by the iron-wu?stite (IW) buffer reaction (FeO -> Fe + O). However, the widespread occurrence of moissanite (SiC) in...Show More Summary

Tectonic settings of continental crust formation: Insights from Pb isotopes in feldspar inclusions in zircon

Most crustal rocks derive from preexisting crust, and so the composition of newly generated (juvenile) continental crust, and hence the tectonic settings of its formation, have remained difficult to determine, especially for the first billion years of Earth’s evolution. Show More Summary

The influence of vegetation on debris-flow initiation during extreme rainfall in the northern Colorado Front Range

We explored regional influences on debris-flow initiation throughout the Colorado Front Range (Colorado, USA) by exploiting a unique data set of more than 1100 debris flows that initiated during a 5 day rainstorm in 2013. Using geospatial...Show More Summary

Modeling the oxygen isotope composition of the Antarctic ice sheet and its significance to Pliocene sea level

Recent estimates of global mean sea level based on the oxygen isotope composition of mid-Pliocene benthic foraminifera vary from 9 to 21 m above present, which has differing implications for the past stability of the Antarctic ice sheet during an interval with atmospheric CO 2 comparable to present. Show More Summary

Abyssal origin for the early Holocene pulse of unradiogenic neodymium isotopes in Atlantic seawater

The neodymium isotopic composition of authigenic phases of deep-sea sediment cores can be interpreted as reflecting past changes in water-mass mixing proportions if end-member water-mass compositions are constrained through time. Here...Show More Summary

Development of cutoff-related knickpoints during early evolution of submarine channels

Submarine channels are often thought of as having relatively simple geometries, with significant along-channel morphologic and stratigraphic continuity. Using high-resolution seismic reflection data from offshore Angola and a kinematic...Show More Summary

Inside baleen: Exceptional microstructure preservation in a late Miocene whale skeleton from Peru

Exceptionally preserved delicate baleen microstructures have been found in association with the skeleton of a late Miocene balaenopteroid whale in a dolomite concretion of the Pisco Formation, Peru. Microanalytical data (scanning electron...Show More Summary

How to make a transverse triple junction--New evidence for the assemblage of Gondwana along the Kaoko-Damara belts, Namibia

T-shaped orogenic triple junctions between mobile belts usually form in two unrelated stages by subsequent and oblique continental collisions separated by a significant time span. Besides these "oblique triple junctions", another type, named "transverse triple junctions", may exist. Show More Summary

Extensive Noachian fluvial systems in Arabia Terra: Implications for early Martian climate

Valley networks are some of the strongest lines of evidence for extensive fluvial activity on early (Noachian; >3.7 Ga) Mars. However, their purported absence on certain ancient terrains, such as Arabia Terra, is at variance with patterns of precipitation as predicted by "warm and wet" climate models. Show More Summary

In situ observations of earthquake-driven fluid pulses within the Japan Trench plate boundary fault zone

Transient fluid flow within faults is suspected to be an important component of the earthquake cycle and subduction zone evolution. However, an understanding of the mechanisms and time scales involved has been limited due to a paucity of direct measurements. Show More Summary

The origin of Earths first continents and the onset of plate tectonics

The growth and recycling of continental crust has resulted in the chemical and thermal modification of Earth’s mantle, hydrosphere, atmosphere, and biosphere for ~4.0 b.y. However, knowledge of the protolith that gave rise to the first continents and whether the environment of formation was a subduction zone still remains unknown. Show More Summary

Criticality in the planform behavior of the Ganges River meanders

The critical point of planform transition from straight to meandering in the wandering Ganges River is identifiable. Recent remote-sensing data indicate that four similar meanders cut off, or attempted to cut off, after ~31–35 yr, primarily due to channel aggradation. Show More Summary

Wyoming on the run--Toward final Paleoproterozoic assembly of Laurentia

Paleoproterozoic suture zones mark the formation of supercontinent Nuna and provide a record of North America’s assembly. Conspicuously young ages (ca. 1.715 Ga) associated with deformation in southeast Wyoming craton argue for a more protracted consolidation of Laurentia, long after peak metamorphism in the Trans-Hudson orogen. Show More Summary

Experimental evidence that clay inhibits bacterial decomposers: Implications for preservation of organic fossils

Exceptionally preserved organic fossils are commonly associated with clay-rich horizons or directly with clay minerals. It has been posited that interactions between clay minerals and organic tissues inhibit enzymatic reactions or protect carcasses in such a way that decay is impeded. Show More Summary

Detecting magma-poor orogens in the detrital record

The clastic record is commonly interrogated by analysis of detrital heavy mineral assemblages, with the bulk of modern detrital geochronological studies employing U-Pb dating of detrital zircon. However, the bias of zircon toward felsic...Show More Summary

The mechanism of partial rupture of a locked megathrust: The role of fault morphology

Assessment of seismic hazard relies on estimates of how large an area of a tectonic fault could potentially rupture in a single earthquake. Vital information for these forecasts includes which areas of a fault are locked and how the fault is segmented. Show More Summary

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