Analyses of more than 40 years of climatic data reveal intriguing spatial variations in climatic patterns for Beringia (North-eastern Siberia and Alaska), aiding the understanding of the hierarchy of climatic controls that operate at different spatial scales within the Arctic. A synoptic climatology, using a subjective classification methodology on January and July sea level pressure, and July ...

This investigation performs diagnostic analyses on NCEP/NCAR re-analysis data, and also does forced, nonlinear, barotropic model calculations to examine the dynamical mechanisms associated with the growth and decay of the PaciŽ c/North American teleconnection pattern (PNA). The diagnostic calculations include projection and composite analyses of each term in the stream-function-tendency equatio...

We investigate in the simplest compact D = 4 N = 1 Type IIB orientifold models the sigma-model symmetry suggested by the proposed duality of these models to heterotic orbifold vacua. This symmetry is known to be present at the classical level, and is associated to a composite connection involving untwisted moduli in the low-energy supergravity theory. In order to study possible anomalies arisin...

The use of induced polarization (IP) methods in oil and gas exploration dates back to the 1930s, but the validity of anomalies has been difficult to establish. Although recent geochemical and downhole research has verified the source of IP anomalies in some geologic environments, the influence of cultural (anthropogenic) features on the electrical data remains a serious stumbling block to the a...

47 The interpretation of the Cretaceous-Paleogene (K-Pg) iridium anomaly – and other 48 impact ejecta – as the result of a single, large asteroid impact has been the subject of much 49 debate, in part due to the distribution of impact markers beyond the narrow confines of the K-Pg 50 boundary sedimentary layer. Here, we revisit the hypothesized processes leading to the shape of 51 K-Pg iridium ...

[1] We model Pn waveforms from two earthquakes in the southwestern United States (Mammoth Lakes, California, and western Nevada) to determine a velocity model of the crustal and mantle structure beneath the southern Sierra Nevada and Walker Lane. We derive a one-dimensional velocity model that includes a smooth crust-mantle transition east of Death Valley and extending south into the eastern Mo...

Geological observations that constrain the history of mantle convection are sparse despite its importance in determining vertical and horizontal plate motions, plate rheology, and magmatism. We use a suite of geological and geophysical observations from the northern North Sea to constrain evolution of the incipient Paleocene-Eocene Icelandic plume. Well data and a three-dimensional seismic surv...

Hydrothermal processes in the Earth’s crust can result in ore deposits characterized by high concentrations of metals with fractal or multifractal properties. This paper shows that stream sediments in the neighborhoods of ore deposits also can have singular properties for ore-mineral and associated toxic trace elements. We propose a new local singularity mapping method for assembling element co...

Economic rare earth element bearing-heavy mineral accommodation in alluvial deposits (stream sediments) is a well-known process caused by varying rates of weathering and transportation heavy minerals sediments, which significant geochemical exploration. In the present work, stream sediment samples from Wadi Lethi, Sharm El-Sheikh, were systematically collected. The collected sediments investiga...