@proceedings {292, title = {Foraminifera ecology on the continental shelf, Merrimack Embayment, Gulf of Maine, New England}, volume = {42}, year = {2010}, note = {Accession Number: 2010-092674; Conference Name: Geological Society of America, Northeastern Section, 45th annual meeting Geological Society of America, Southeastern Section, 59th annual meeting; Baltimore, MD, United States; Conference Date: 20100314; Language: English; Coordinates: N423000N430000W0703000W0705000; Coden: GAAPBC; Collation: 1; Collation: 82; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201049; Monograph Title: Geological Society of America, Northeastern Section, 45th annual meeting; Geological Society of America, Southeastern Section, 59th annual meeting; joint meeting, abstracts volume; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2010/03/01/}, pages = {82 - 82}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {During the late Pleistocene the Merrimack River paleodelta formed as post-glacial rebound produced a local low stand in sea level. Drowned as sea level rose, the paleodelta is now being reworked by a variety of processes. This study uses benthic foraminifera as a biotic and environmental proxy to study the sand and gravel resources of the paleodelta. Nineteen sediment samples were collected from the paleodelta along two east-west transects east of the Merrimack River. From these samples nearly 6000 benthic foraminifera, representing 62 species, were collected and identified. Although dissolution compromised the preservation of calcite tests within six samples, the resulting data is robust and allows for numerous conclusions to be drawn. Specifically, benthic foraminifera become more common distally and specific species inhabit specific areas of the paleodelta. Distribution patterns of some species have changed significantly since the late 1940s, with some species migrating landward, others, seaward. Distributions of some taxa differ significantly between the two transects, both in the present day and from the past. These differences may point to the influence of, and changes in, the Merrimack River outflow upon water column nutrient delivery, productivity and food availability over the past 60 years. Species diversity and evenness peak at the delta break, coincident with low species dominance at 50 meters water depth. Q-mode cluster analyses show three distinct assemblages, "shallow" (< or =30 meters water depth), "deep" (> or =40 meters), and "delta edge" (50 meters). There is no apparent correlation between foraminiferal distributions and deltaic bedforms, and in turn, sediment type. This implies that foraminiferal distributions are controlled by other environmental variables such as food. In summary, benthic foraminiferal assemblage analyses complement geophysical techniques. Benthic foraminifera can also help assess the marine impact of, e.g., mining sediment resources, watershed development, pollution, rising sea level, and increased fishing.}, keywords = {$\#$StaffPubs, applications, Atlantic Ocean, benthic taxa, Cenozoic, cluster analysis, deltaic environment, Economic geology, geology of nonmetal deposits 28A, Foraminifera, gravel deposits, Gulf of Maine, Invertebrata, Maine, marine environment, marine sediments, massachusetts, Merrimack River valley, microfossils, mining, North Atlantic, paleoecology, paleogeography, Pleistocene, Protista, Quaternary, Quaternary geology 24, sand deposits, sea-level changes, sediments, shelf environment, species diversity, statistical analysis, United States, upper Pleistocene}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2010NE/finalprogram/abstract_170108.htm}, author = {Steven A Nathan and Leckie, R. Mark and Stephen B Mabee} } @article {274, title = {Comparison of three fracture sampling methods for layered rocks}, journal = {International Journal of Rock Mechanics and Mining Sciences [1997]}, volume = {47}, year = {2010}, note = {Accession Number: 2010-041538; Language: English; Coordinates: N441500N452000W0865600W0880000; Coden: IJRMA2; Collation: 9; Publication Types: Serial; Updated Code: 201023; Illustration(s): illus. incl. 4 tables; Number of References: 25; Reviewed Item: Analytic}, month = {2010/02/01/}, pages = {218 - 226}, publisher = {Elsevier : Oxford-New York, International}, address = {International}, abstract = {Three methods of fracture data collection are tested against each other in layered dolomitic rocks to evaluate the effectiveness of each method in sampling fracture properties. The methods tested are the single scanline method (SSM), selection method (SM), and multiple scanline method (MSM). Finite element techniques were first used to build a base model with the exact locations, sizes and orientations of each fracture observed in the natural fracture network. Then, a second set of models were stochastically generated using statistics from each sampling technique. For each network, the overall fracture intensity was used to assess the effectiveness of each sampling technique in capturing the real fracture properties. Fracture network permeability was also calculated for each of two directions to evaluate the transmissive properties of the networks. Although all three methods produced good matches of relative intensity and permeability between natural and synthetic fractures, the results reveal that a well-placed scanline performed the best at recreating natural fractures. However, the results from one variation of the SSM were only slightly better than the results from both versions of the SM. In general, the SSM provides the best results but possibly at heavy costs in time and labor, whereas the SM gives comparable results with less expenditure of energy and time. Thus, the SM is an adequate technique and recommended for use at large outcrops or where time, access or budget constraints are a concern.}, keywords = {$\#$StaffPubs, Big Quarry, carbonates, case studies, data acquisition, data processing, dolomite, Door Peninsula, fractures, geographic information systems, ground water, information systems, joints, layered materials, mapping, methods, movement, multiple scanline method, northeastern Wisconsin, numerical models, permeability, sampling, selection method, simulation, single scanline method, statistical analysis, Structural geology 16, style, three-dimensional models, United States, Wisconsin}, isbn = {13651609}, url = {http://www.sciencedirect.com/science/article/pii/S1365160909001804}, author = {Alex K Manda and Stephen B Mabee} }