Petrogenetic model for the origin of carbonatites

The petrological significance and distribution of igneous carbonatites is discussed. Particular attention is paid to the relationship that exists between carbonatites and volcanism in East Africa. Using a simple model of a carbonatite-nephelinite-ijolite volcanic complex it was discovered that all the peralkaline and carbonatitic rocks found in such a complex could be derived from a single primary nephelinitic magma. The origin of such a primary magma, and the subsequent evolution carbonatitic sub-magmas, is examined.     

Relationships between heavy metals and major cations along pollution gradients

Along some pollution gradients, animal tissue concentrations of several major, physiologically important cations vary greatly in a way that corresponds with levels of toxic metals. Changes in concentration from normal of these major cations can be as much as fourfold which may be an underlying cause of much of the stress experienced by these species in polluted environments.     

Nonlocal fluxes and Stokes drift effects in the K-profile parameterization

 The K-profile parameterization of upper-ocean mixing is tested and extended using observations and large eddy simulations of upper-ocean response to a westerly windburst. A nonlocal momentum flux term is added, and the amplitude of the nonlocal scalar flux is recalibrated. Parameterizations of Stokes drift effects are added following recent work by McWilliams and Sullivan (2001). These changes allow the parameterization to produce both realistic gradients of momentum and scalars in the nocturnal boundary layer and enhanced mixing during stable conditions. The revised parameterization is expected to produce improved representations of lateral advection and sea-surface temperature in large-scale models. Received: 31 August 2001 / Accepted: 15 December 2001     

Simulating flood events at the Twin Ports of Duluth-Superior using a linked hydrologic-hydrodynamic framework

Ocean Dynamics - Generally, ports in the North American Great Lakes are not supported with navigational guidance (water level, water temperature, currents, ice) by NOAA’s Great Lakes...     

Adaptive generalized multiscale approximation of a mixed finite element method with velocity elimination

Computational Geosciences - In this paper, we propose offline and online adaptive enrichment algorithms for the generalized multiscale approximation of a mixed finite element method with velocity...