Present-day precipitation of lead and zinc from groundwaters

Small quantities of galena and sphalerite are currently precipitating 26m below the surface, at the Vinemount quarry, Ontario, Canada from sulfurous spring waters, issuing from carbonates of the Lockport Formation. At the spring orifices, these sulfides are present in both fracture coatings and an associated black sludge. These precipitates are overlain by a crust rich in native sulfur. The mineralogy of the precipitates, and the chemistry of waters taken from three consistent spring horizons, indicates that downward-moving meteoric groundwaters leach metals from the host rocks and precipitate galena and sphalerite on encountering H₂S-rich waters at the water table. While our observation of the transport and deposition of lead and zinc by shallow groundwaters lends support to intra-karstic models for the direct precipitation of galena and sphalerite, it also enables us to propose that many carbonate-hosted Pb-Zn deposits, of differing theories of origin, may have been enriched during periods of uplift.     

The use of transplanted cultured mussels (Mytilus edulis) to monitor pollutants along the Ninety Mile Beach, Victoria, Australia— II. Polychlorinated dibenzo-p-dioxins and dibenzofurans

Commercially cultured strings of mussels were transplanted to five sites along the Ninety Mile Beach, Victoria, Australia, to assess the operational impact of an ocean outfall on bioaccumulation of dioxins and furans. The monitored outfall discharges a complex effluent containing secondary treated domestic, industrial and pulp and paper mill effluent as well as oil and gas production waste waters. Mussels were deployed twice yearly for a period of 3 years, with both pre-discharge and post-discharge data collected. Mussel tissue furan concentrations were generally below detection limits, whereas dioxins were detected in all tissue samples. Tissue dioxin congener profiles were similar to unpolluted seawater, with penta-, hepta- and octa-substituted dioxin congeners being detected in the highest concentrations. Tissue concentrations of dioxins and furans in deployed mussels provided no evidence to suggest that bioaccumulation of dioxins discharged from the ocean outfall was occurring.     

Observations on elephant mortality and bones in water holes

An unusually severe drought in 1982 led to a temporary die-off of elephants at a natural water source in Hwange National Park, Zimbabwe. Compared to living populations, the age structure of the animals killed by drought is strongly biased toward 2-to 8-year-old animals. However, the fresh carcasses of these young elephants were commingled with weathered remains of adults that had died earlier, creating a mixed skeletal sample whose age structure was much closer to that of living populations. Observations of elephant bones that have accumulated due to natural mortality at water holes might provide analogs for paleoecological interpretations of fossil proboscidean assemblages.     

On the possible utilization of Camelops by early man in North America

Camelops was a major faunal element in late Wisconsin biotic communities over much of North America. Interpretations of possible human association with Camelops are often based on poorly evaluated evidence. Ideal standards for acceptable evidence are compared here to the actual evidence that has been advanced. Of 25 fossil assemblages examined, 2 might be examples only of geological contemporaneity of humans and Camelops; 2 might indicate behavioral association of humans and Camelops bones; and 2 might indicate actual human utilization of Camelops (killing and/or butchering). Camelops bones interpreted as artifacts are similar to modern specimens affected by noncultural processes.     

IPUMS-Terra: integrated big heterogeneous spatiotemporal data analysis system

Big Geo Data promises tremendous benefits to the GIS Science community in particular and the broader scientific community in general, but has been primarily of use to the relatively small body of GIScientists who possess the specialized knowledge and methods necessary for working with this class of data. Much of the greater scientific community is not equipped with the expert knowledge and techniques necessary to fully take advantage of the promise of big spatial data. IPUMS-Terra provides integrated spatiotemporal data to these scholars by simplifying access to thousands of raster and vector datasets, integrating them and providing them in formats that are useable to a broad array of research disciplines. IPUMS-Terra exemplifies a new class of National Spatial Data Infrastructure because it connects a large spatial data repository to advanced computational resources, allowing users to access the needle of information they need from the haystack of big spatial data. The project is trailblazing in its commitment to the open sharing of spatial data and spatial tool development, including describing its architecture, process development workflows, and openly sharing its products for the general use of the scientific community.     

Extragalactic HI surveys

We review the results of HI line surveys of extragalactic sources in the local Universe. In the last two decades major efforts have been made in establishing on firm statistical grounds the properties of the HI source population, the two most prominent being the HI Parkes All Sky Survey and the Arecibo Legacy Fast ALFA survey. We review the choices of technical parameters in the design and optimization of spectro-photometric “blind” HI surveys, which for the first time produced extensive HI-selected data sets. Particular attention is given to the relationship between optical and HI populations, the differences in their clustering properties and the importance of HI-selected samples in contributing to the understanding of apparent conflicts between observation and theory on the abundance of low mass halos. The last section of this paper provides an overview of currently ongoing and planned surveys which will explore the cosmic evolution of properties of the HI population.     

Kersey–Kuner terrace investigations at the Dent and Bernhardt sites,Colorado

The Dent site provided the first association of fluted points with mammoth bones in the New World. However, the stratigraphic integrity of the site has remained in doubt since the original excavations in 1932 and 1933. Core sampling at the Dent Clovis site indicates that the site, on Kersey terrace gravel, extends under railroad tracks adjacent to the original area of excavation. Four hundred meters south the Kuner strath terrace has been exposed by a roadcut at the Bernhardt site. An Archaic hearth dated 4030 ± 60 B.P. is near the top of a 1-m-thick eolian sand overlying 1 m of fine-grained alluvium dated 5740 ± 60 B.P., which in turn overlies sand and gravel of the Kuner strath terrace with an AMS radiocarbon age of 10,105 ± 90 B.P. The South Platte River appears to have been quasistable at the Kuner level during the Younger Dryas when Paleoindians from Clovis to Cody hunted megafauna on the Kersey terrace. © 1998 John Wiley & Sons, Inc.     

Design and routing of storm flows in an urbanized watershed without surface streams

In the karst geologic setting of Greenbrier County, West Virginia, USA, the drainage network in the watersheds do not support surface streams, but depend entirely on sinkholes, solution cavities, or injection wells as discharge points for accumulated storm water. By providing a systematic framework for designing and routing storms in this geologic setting, functioning retention and attenuation structures have been developed which are protective of water quality while still safely discharging storm water in a controlled manner to the subsurface. This article provides a rationale for the design methodology and then examines the successful implementation of an attenuation and storm water retention design to manage the surface discharges for an entire watershed. By examining the pre-development flows and evaluating future land use patterns (i.e., installation of impermeable surfaces over large areas), as well as sinkhole conveyance capabilities, it was necessary to examine alternative disposal options for collected storm water as well as devise a basin-wide management strategy to coordinate future development of the watershed. Additionally, innovative water quality measures were implemented to help prevent contamination from preferentially infiltrating into the subsurface as a result of these land development activities.