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Quantifying the rise of the Himalaya orogen and implications for the South Asian monsoon

We reconstruct the rise of a segment of the southern flank of the Himalaya-Tibet orogen, to the south of the Lhasa terrane, using a paleoaltimeter based on paleoenthalpy encoded in fossil leaves from two new assemblages in southern Tibet (Liuqu and Qiabulin) and four previously known floras from the Himalaya foreland basin. Show More Summary

Fault-controlled dolomitization in a rift basin

There are numerous examples of fault-controlled, so-called hydrothermal dolomite (HTD), many of which host economic mineral deposits or hydrocarbons, but there remains a lack of consensus as to how they form. In particular, multiple phases of diagenetic overprinting can obscure geochemical fingerprints. Show More Summary

Location, location, location: The variable lifespan of the Laramide orogeny

The Laramide orogeny had a spatially variable lifespan, which we explain using a geodynamic model that incorporates onset and demise of flat-slab subduction. Laramide shortening and attendant uplift began in southeast California (USA) at ca. Show More Summary

Accelerating slip rates on the Puente Hills blind thrust fault system beneath metropolitan Los Angeles, California, USA

Slip rates represent the average displacement across a fault over time and are essential to estimating earthquake recurrence for probabilistic seismic hazard assessments. We demonstrate that the slip rate on the western segment of the...Show More Summary

Equable end Mesoproterozoic climate in the absence of high CO2

The Proterozoic Eon (2500–542 Ma) appears to have been a warm period bookended by glaciations, despite a 5%–18% reduction in solar output compared to modern during this interval. Radiative-convective climate models suggest that glaciation could have been avoided if p CO 2 were 30–300 x preindustrial atmospheric levels (PIAL, 280 ppmv). Show More Summary

Ultrafast magmatic buildup and diversification to produce continental crust during subduction

The processes and fluxes that produce the distinct compositional structure of Earth’s continental crust by subduction remain controversial. The rates of oceanic crust production, in contrast, are well quantified and are generally believed to be faster than those responsible for building magmatic systems in subduction settings. Show More Summary

A rapid lake-shallowing event terminated preservation of the Miocene Clarkia Fossil Konservat-Lagersta?tte (Idaho, USA)

The world-renowned middle Miocene Clarkia lacustrine deposits (15.4–16.0 Ma) in northern Idaho, United States, known as Fossil Lagersta?tten, yield extraordinary fossils that preserve in situ ancient biomolecules and organic biomarkers. Show More Summary

What sets the size of current ripples?

Water flowing over sand in fluvial and marine settings often results in the formation of current ripples. Found in modern and ancient deposits on Earth and Mars, ripple stratification records flow directions and fluid properties that are crucial to interpreting sedimentary records. Show More Summary

The Mw 8.3 Illapel earthquake (Chile): Preseismic and postseismic activity associated with hydrated slab structures

The accumulated stress in subduction zones is discharged with earthquake and aseismic activity; the latter is hosted in rheological complex regions, characterized by high pore fluid pressure, and is often accompanied by repeated earthquakes and earthquake swarms. Show More Summary

Late Quaternary glacial dynamics and sedimentation variability in the Bering Trough, Gulf of Alaska

Ice dynamics, tectonic setting, and sediment supply are the key parameters controlling the architecture of high-latitude margins and the formation of trough mouth fans (TMFs). Current understanding of these archives of paleo–ice streams...Show More Summary

A new Early Jurassic (ca. 183 Ma) fossil Lagersta?tte from Ya Ha Tinda, Alberta, Canada

Lagersta?tten—deposits of exceptionally preserved fossils—offer vital insights into evolutionary history. To date, only three Konservat-Lagersta?tten are known from Early Jurassic marine rocks (Osteno, Posidonia Shale, and Strawberry Bank), all located in Europe. Show More Summary

Flexible and responsive growth strategy of the Ediacaran skeletal Cloudina from the Nama Group, Namibia

The Ediacaran skeletal tubular putative metazoan Cloudina occurs globally in carbonate settings, which both provided lithified substrates and minimized the cost of skeletonization. Habitat and substrate preferences and the relationship...Show More Summary

The origin of contractional structures in extensional gneiss domes

The juxtaposition of domains of shortening and extension at different scales in orogens has fueled many debates about driving forces and tectonic interpretations, including timing of deformation. At the orogen scale, gravitational collapse and mass transfer from orogenic plateaux to forelands explain some of these juxtapositions. Show More Summary

Combining Nd isotopes in monazite and Hf isotopes in zircon to understand complex open-system processes in granitic magmas

Mapping the age and trace element and Sm-Nd isotope compositions of monazite grains from a peraluminous Cretaceous granite using laser ablation–split stream analysis reveals a wide range in Nd isotope and rare earth element (REE) compositions within and between single grains. Show More Summary

Coupling leeside grainfall to avalanche characteristics in aeolian dune dynamics

Avalanche (grainflow) processes are fundamental drivers of dune morphodynamics and are typically initiated by grainfall accumulations. In sedimentary systems, however, the dynamism between grainfall and grainflow remains unspecified because simple measurements are hampered by the inherent instability of lee slopes. Show More Summary

Temperature and volume of global marine sediments

Marine sediments contribute significantly to global element cycles on multiple time scales. This is due in large part to microbial activity in the shallower layers and abiotic reactions resulting from increasing temperatures and pressures at greater depths. Show More Summary

Fossil forest reveals sunspot activity in the early Permian

Modern-day periodic climate pattern variations related to solar activity are well known. High-resolution records such as varves, ice cores, and tree-ring sequences are commonly used for reconstructing climatic variations in the younger geological history. Show More Summary

Forecasting transitions in monogenetic eruptions using the geologic record

Spatial forecasting of volcanism and associated hazards in intraplate monogenetic volcanic fields is subject to large uncertainties in both data and models. We demonstrate a novel logistic regression method for mapping phreatomagmatic-magmatic eruption transition susceptibility using near-surface hydrologic, topographic, and geologic data. Show More Summary

Liveblogging the Deluge: Big Changes on the Tuolumne River

Source: I've been away for the last five days, experiencing California's storms from an entirely different perspective, that of being exposed and out in the open country of Death Valley National Park. Show More Summary

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