51 resultados para Boston Harbor (Mass.)--Maps
Resumo:
One particularly complex phenomenon is the episodic, tidally driven variation of navigable depth level as a result of fluid mud settlement. This paper presents results from dynamic cone penetration testing with pore pressure measurement (CPTU) as a nonacoustical, direct device to support surveying and management of these areas. The new technique is modular and uses a disk configuration for fluid mud detection. Both disk resistance and pore pressure measurements accurately identify suspended matter concentrations of 90 g/L or more, and the transition from fluid mud to consolidating mud once concentrations exceed 150 g/L. Hence, the procedure attests the potential for rapid, reliable assessment of a fluid mud layer and concurrent characterization of the underlying consolidated sediment by monitoring the pore pressure and strength changes during penetration.
Resumo:
In this article, methods and results are presented for the analysis of the behaviour of an alpine glacier, the Vernagtferner, Oetztal Alps, Austria. Since 1601, the advances and retreats of Vernagtferner are documented and analysed with rising temporal and spa- tial precision. Early pictorial documents (from 1601 to 1844), high-resolution maps since 1889, mass balance investigations with the glaciological method since 1964 and meteorological-hydrological records and models since 1974 deliver, with increasing temporal resolution, a consistent pattern of the continual ice loss of this glacier over more than 30 years.