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C. Brown

Publications and source records attributed to C. Brown.

10 recordsLinked to original sources

User's guide and metadata for WestuRe: U.S. Pacific Coast estuary/watershed data and R tools

Overview There are about 350 estuaries along the U.S. Pacific Coast (U.S. Fish andWildlife 2011). Basic descriptive data for these estuaries, such as their size and watershed area, are important for coastal-scale research and conservation planning. However, this information is spread among many sources, making it difficult to find and standardize. The goal of the WestuRe Project is to provide a framework to: (1) make general descriptive data for estuaries and their watersheds more accessible, and (2) provide tools to make analyzing and visualizing these data easier. The WestuRe download includes data describing U.S. Pacific Coast estuaries and their corresponding watersheds from northern Washington (including the region located along the Strait of Juan de Fuca that goes from Port Townsend to Cape Flattery, 48.383°N) to southern California (Tijuana Estuary, 32.557°N), excluding Puget Sound proper and coastal islands (Fig. 1). The WestuRe data currently include shapefiles of estuary and watershed polygons as well as CSV files summarizing geomorphological and climate data (Fig. 2, Section 2). The WestuRe tools help users extract and view relevant data using the statistical program R and Google Earth (Fig. 3, Section 3). Potential applications of the data include: Describing and comparing estuaries and watersheds at the landscape scale Identifying relationships between estuary/watershed variables Incorporating estuary/watershed attributes in models to predict species and habitat distributions Classifying estuaries according to morphology, climate, and habitat (Lee and Brown 2009)

California, Oregon, Washington

Is the Tinaquillo, Venezuela, "Pseudogabbro" metamorphic or magmatic?

The " pseudogabbro " associated with peridotite at Tinaquillo , Venezuela , is believed to be of magmatic rather than metamorphic origin principally because: (1) there are major mineralogic and compositional differences between the " pseudogabbro " and the most highly metamorphosed country rock; (2) rocks intermediate in compositional between peridotite and " pseudogabbro " are present; (3) augen of lamellar pyroxene which occur in the " pseudogabbro " but not in the country rock are of a kind found elsewhere rarely except in igneous rocks; (4) gabbroic rocks are associated with peridotite elsewhere in Venezuela and in the Carribbean region; (5) textural and structural features of the kind found in the Tinaquillo rocks are characteristic of alpine-type peridotite-gabbro complexes.

Tinaquillo