John J. Fisher

Electric-hydraulic conductivity correlation in fractured crystalline bedrock: Central Landfill, Rhode Island, USA

Remote sensing and geoelectrical methods were used to find water-bearing fractures in the Scituate granite under the Central Landfill of Rhode Island. These studies were necessary to evaluate the integrity of the sanitary landfill and for planning safe landfill extensions. The most useful results were obtained with fracture trace analysis using Landsat and SLAR imagery in combination with ground-based resistivity measurements using Schlumberger vertical electrical soundings based on the assumption of horizontally layered strata. Test borings and packer tests confirmed, in the presence of a lineament and low bedrock resistivity, the probable existence of high bedrock fracture density and high average hydraulic conductivity. However, not every lineament was found to be associated with high fracture density and high hydraulic conductivity. Lineaments alone are not a reliable basis for characterising a landfill site as being affected by fractured bedrock. Horizontal fractures were found in borings located away from lineaments. High values of hydraulic conductivity were correlated with low bedrock resistivities. Bedrock resistivities between 60 and 700 Ω m were associated with average hydraulic conductivities between 4 and 60 cm/day. In some cases very low resistivities were confined to the upper part of the bedrock where the hydraulic conductivity was very large. These types of fractures apparently become narrower in aperture with depth. Bedrock zones having resistivities greater than 1000 Ω m showed, without exception, no flow to the test wells. Plots of bedrock resistivity versus the average hydraulic conductivity indicate that the resistivity decreases with increasing hydraulic conductivity. This relationship is inverse to that found in most unconsolidated sediments and is useful for estimating the hydraulic conductivity in groundwater surveys in fractured bedrock. In appropriate settings such as the Central Landfill site in New England, this electric-hydraulic correlation relationship, supplemented by lineament trace analysis, can be used effectively to estimate the hydraulic conductivity in bedrock from only a limited number of resistivity depth soundings and test wells.

Regional Long-Term and Localized Short-Term Coastal Environmental Geomorphology Inventories

Applied coastal geomorphological research has recently become a necessity for many projects. Baseline inventories are used for environmental impact studies for all federal and many state coastal projects. Coastal inventories are conducted for coastal land use planning under the Federal Coastal Zone Management Act and for the Federal Coastal Flood Insurance Program. Such applied coastal geomorphological investigations can be concerned with both regional and detailed studies. Regional studies, covering a state’s entire coastline or large physiographic unit such as a bay, are necessary for the above mentioned inventories and long range planning. In contrast, detailed localized studies usually cover a particular beach, inlet or smaller shoreform, and are usually conducted in response to a specific problem such as erosion, shoaling or even pollution.

SHORELINE CHANGE AT THOMPSON ISLAND, BOSTON HARBOR, MASSACHUSETTS, 1938-1977

A photogrammetric and sediment analysis is presented to illustrate the relationship between beach erosion and seacliff recession on Thompson Island, Boston Harbor, Massachusetts. Aerial photographs taken in 1938, 1952, 1963, and 1977 were measured to determine rates of shoreline change around the island. The 39-year average rate of beach erosion is 0.3 m/yr ± 2% with an average rate of cliff recession at 0.2 m/yr ± 2%. Rates of beach erosion between six orientations that reflect principal wave approach to the island were not found to be significantly different (0.05) for the 39-year period. The rank order correlation between beach erosion and cliff recession for these six orientations was moderately well correlated (0.63). To determine possible controls of cliff erosion, 58 sediment samples were collected from glacial cliffs along the shoreline. The textural composition was determined, and then tested with discriminant function analysis. Partial correlation analysis between beach erosion and cliff recessi...

Environmental and structural implications of Rhode Island seismic events, 1965–1976

Rhode Island, like most of New England, is in a mainly quiet seismic region, and thus, few epicenter locations are available to determine seismically active fault traces. This lack of information has hindered environmental impact siting studies for nuclear power plants because such studies must locate any “capable” (active) faults. Reinvestigation and evaluation of four Rhode Island earthquakes that occurred during the past 12 yr (1965, 1967, 1974, and 1976) indicate that the earthquakes were related to regional lineaments, which are probably caused by faults. In this area of low seismic activity, only isoseismal mapping–rather than simple epicenter locations–can indicate these lineaments. Two of these seismically located lineaments, paralleling each other and trending east, are at the head and mouth of Narragansett Bay, and a third lineament trends northeast through Narragansett Bay itself and along the Taunton River into Massachusetts. Recent re-exploration of coal resources in the Pennsylvanian Narragansett basin in this area has suggested potential new faults. No field relationship between this seismicity and the few known, mapped faults exists, but extensive Pleistocene glacial deposits in the area obscure many geologic structures. In addition, the faults indicated by these regional lineaments may be deeply buried basement features that have been reactivated at various times, at different degrees of activity, up to the present.

Red cell volume (RCV) and blood volume (BV estimation in transfused preterm infants (PTI): a “real-time” method based on a donor-recipient red cell antigen “mismatches”

Red cell volume (RCV) and blood volume (BV estimation in transfused preterm infants (PTI): a “real-time” method based on a donor-recipient red cell antigen “mismatches”

FORESHORE DEPOSITIONAL PATTERNS ALONG THE RHODE ISLAND SOUTHSHORE

An application of polynomial curve fitting to sediment cumulative frequency distributions is presented to delineate the foreshore depositional patterns along the barrier beaches of the Rhode Island southshore. The analysis is based on 92 sampled stations where data for beach geometry, tidal stage, and sediment size were collected. Using the size-frequency classes obtained from sieving the foreshore sediment samples at 0.25 O intervals and fitting third-degree polynomial equations to these data, over 94% of the variation within the sediment cumulative frequency distributions is explained. The four curve coefficients (a, b, c, d) derived from the predicted third-degree equation are used in a discriminant function analysis to test the relationship between the curve shape and sediment source. Comparison of the discriminant scores with the respective station locations suggests that a series of Pleistocene headlands which occur as discrete points along the beach are serving as independent sources of sediment fo...