Distinctive uppermost Ediacaran–Ordovician rocks (Avalonian overstep sequence) were key in definition of Avalonia, which comprises large areas the NE Appalachians and Caledonian Variscan mountains (Britain western Europe). This siliciclastic-dominated cover succession unconformably overlies a Neoproterozoic pre-Avalonian basement collage (arc, continental, oceanic fragments; Gwna-type melanges ...

First large-scale concentration of gold to ore grade in Earth’s crust took place at around 2.9 Ga quartz-pebble conglomerates, well before endogenous deposits, such as porphyry and epithermal systems or orogenic-type started play a significant role from ca. 2.75 onwards. The conglomerate-hosted placers, typified by those the Mesoarchaeaen Witwatersrand Basin South Africa, are thought have been ...

The Yacoraite Formation (Salta rift, Argentina) consists of Maastrichtian–Danian lacustrine carbonate and siliciclastic deposits with interbedded volcanic ash layers, organized in four third-order stratigraphic sequences. It offers the exceptional opportunity to jointly apply situ zircon U-Pb laser ablation-inductively coupled plasma mass spectrometry geochronology that resulted two distinct de...

Abstract A procedure to automatically correlate well logs measured in boreholes that are located continental siliciclastic basins by using two different methods is shown. The first method applied the parametric layers were determined each borehole starting from values of their geophysical parameters and consists correlating, cross-association, columns formed these layers. second cross-correlati...

The lateral sealing ability of a normal fault is a major factor in creating hydrocarbon traps. Therefore, a methodology for assessing the sealing ability of faults in the siliciclastic sequences of subsidence basins has been established; moreover, by using this methodology, the uncertainty inherent in hydrocarbon exploration can be decreased. Moreover, the petrophysical properties of fault roc...

A modeling study was conducted to evaluate the acid-base chemistry of streams within Shenandoah National Park, Virginia and to project future responses to sulfur (S) and nitrogen (N) atmospheric emissions controls. Many of the major stream systems in the park have acid neutralizing capacity (ANC) less than 20 microeq/L, levels at which chronic and/or episodic adverse impacts on native brook tro...

2016 desert symposium e Bouse Formation provides a sedimentary record of the rst arrival of the Colorado River, water and sediment, as it was integrated from the Colorado Plateau to the Gulf of California 5–6 Ma. is unit is generally thin (10–100s m) but widespread within basins in the lower Colorado River corridor that extend from Lake Mead to Yuma (Fig. 1). e basins are interpreted to have be...

The Ediacaran-Cambrian transition interval is described for the west part of Gondwana Supercontinent. This key in Earth’s history recorded upper and lower Tagatiya Guazú Cerro Curuzu formations, Itapucumi Group, Paraguay, encompassing a sedimentary succession deposited tidally influenced mixed carbonate-siliciclastic ramp. remarkable presence cosmopolitan Ediacaran shelly fossils treptichnids, ...

Understanding how regional ecosystems respond to sea-level and environmental perturbations is a main challenge in palaeoecology. Here we use quantitative abundance estimates, integrated within a sequence stratigraphic and environmental framework, to reconstruct benthic community changes through the 13 myr history of the Jurassic Sundance Seaway in the western United States. Sundance Seaway comm...

An integrated lithologic, paleontologic, and multi-proxy geochemical study of the Middle Devonian Oatka Creek Formation, a black shale in the northern Appalachian Basin, indicates that a number of different factors contributed to organic carbon-rich black shale deposition. Conditions leading to this organic-rich sedimentary deposit were ultimately controlled by a relative sealevel rise, dominan...