نتایج جستجو برای: litho geochemical anomaly

تعداد نتایج: 51132  

2004
Qiaolin Zhang Paul Friedberg Cherry Tang Bhanwar Singh Kameshwar Poolla Costas J. Spanos

This paper describes a novel approach to improving across-wafer CD uniformity through the litho-etch sequence. Our approach is to compensate for systematic CD perturbations by employing all available control authority though the litho-etch process sequence. In particular, we find that the most effective control input for regulating spatial variations in CD is found in the post exposure bake (PE...

Hanza region is located in the southern part of Urumieh–Dokhtar Metallogenic belt in southeastern Iran. This region includes six known porphyry copper deposits and it is considered as an ore- bearing region from geochemical point of view. The aim of this research is to examine effective processing techniques in the analysis of stream sediment geochemical datasets and ASTER satellite images. The...

2005
Norman R. Carlson Kenneth L. Zonge

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...

2014
Pincelli M. Hull Peter J. S. Franks Richard D. Norris

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 ...

2003
Brian Savage Chen Ji Don V. Helmberger

[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...

Journal: :Frontiers in Earth Science 2023

Litho-facies classification is an essential task in characterizing the complex reservoirs petroleum exploration and subsequent field development. The lithofacies at borehole locations detailed but lacks providing larger coverage areas. acquired 3D seismic data provides global for studying reservoir facies heterogeneities study area. This applies six supervised machine learning techniques (Rando...

2017
G. Stucky G. G. Roberts A.-L. Jackson

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...

Journal: :Computers & Geosciences 2009
Qiuming Cheng Frederik P. Agterberg

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...

2015
Lingqing Wang Tao Liang

Rare earth mine tailing dumps are environmental hazards because tailing easily leaches and erodes by water and wind. To assess the influence of mine tailing on the geochemical behavior of rare earth elements (REEs) in soil, sixty-seven surface soil samples and three soil profile samples were collected from different locations near China's largest rare earth mine tailing. The total concentration...

Journal: :Iraqi geological journal 2023

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...

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