87Sr/86Sr and 18O/16O isotopic systematics and geochemistry of granitoid plutons across a steeply-dipping boundary between contrasting lithospheric blocks in western Idaho

A spatially abrupt geochemical boundary is preserved within four plutonic complexes along the western margin of the Cretaceous Idaho Batholith near McCall, Idaho. These intrusives ranging in composition from tonalite to granite were emplaced across a regional boundary between accreted oceanic-arc terranes and the continental margin, and their isotopic, major-element, and trace-element geochemistry provide detailed information about this change in crustal characteristics at depth, indicating that the boundary is nearly vertical and extends deep into the lithosphere. The Hazard Creek complex, emplaced west of the transition in wall-rock lithology, has initial ⁸⁷Sr/⁸⁶Sr (R_i) less than 0.7045 and ¹⁸O greater than 7.5, indicating little or no continental crust in its source region; however, elevated ¹⁸O requires some incorporation of rocks formed or altered at the earth's surface. A large shift in R_i and ¹⁸O is observed across the 5–8 km wide Little Goose Creek complex, which was emplaced across the wall-rock boundary. This is interpreted as mixing between: (1) a basaltic or andesitic magma with low K₂O and high Na₂O, Al₂O₃, and Sr, similar to that forming the Hazard Creek complex; and (2) materials similar to Precambrian sedimentary sedimentary rocks with low Sr, high ¹⁸O (+15) and high R_i (0.83 at 100 Ma). The Payette River complex, emplaced east of the wall-rock boundary, exhibits at least one additional component with low ¹⁸O (+6), moderate R_i (0.708) and mafic composition. This component is inferred to be old basaltic material in the lower crust or upper mantle similar to that inferred to be a minor part of the Peninsular Ranges Batholith in SE California (Silver et al. 1979; Hill et al. 1986). The easternmost complex in the Idaho transect is made up of granites that may contain a component of granitic cratonal basement. The entire west-to-east geochemical transition from oceanic-arc magmas to cratonal magmas takes place over a lateral distance of less than 20 km. Although the zone of transitional protolith dominated by metasedimentary rocks is unusually narrow and may have been in part tectonically removed, the striking geochemical similarities between this traverse and several other transects across much broader areas of Nevada and California suggest that the craton itself was not rifted apart, but that juxtaposition of the accreted oceanic-arc terranes occurred along the preexisting craton margin. The data confirm that the isotopic geochemistry of granitoid plutons can be used as a probe of deep lithospheric character, and that major lateral variations in the lithosphere on the order of one to two kilometers in width can be recognized in favorable circumstances.     

Pullout behavior of biocement–geosynthetic reinforcement system: a parametric study

Acta Geotechnica - In the biocement–geosynthetic system, biocement is combined with geosynthetic to increase the pullout resistance of the geosynthetic and thereby the stability of reinforced...     

Intelligent ship traffic monitoring for oil spill prevention: risk based decision support building on AIS

The paper describes a model, which estimates the risk levels of individual crude oil tankers. The intended use of the model, which is ready for trial implementation at The Norwegian Coastal Administrations new Vard? VTS (Vessel Traffic Service) centre, is to facilitate the comparison of ships and to support a risk based decision on which ships to focus attention on. For a VTS operator, tasked with monitoring hundreds of ships, this is a valuable decision support tool. The model answers the question, "Which ships are likely to produce an oil spill accident, and how much is it likely to spill?".     

Integrated estimates of global terrestrial carbon sequestration

Assessing the contribution of terrestrial carbon sequestration to climate change mitigation requires integration across scientific and disciplinary boundaries. A comprehensive analysis incorporating ecologic, geographic and economic data was used to develop terrestrial carbon sequestration estimates for agricultural soil carbon, reforestation and pasture management. These estimates were applied in the MiniCAM integrated assessment model to evaluate mitigation strategies within policy and technology scenarios aimed at achieving atmospheric greenhouse gas stabilization by 2100. Terrestrial sequestration reaches a peak rate of 0.5–0.7 GtC yr⁻¹ in mid-century with contributions from agricultural soils (0.21 GtC yr⁻¹), reforestation (0.31 GtC yr⁻¹) and pasture (0.15 GtC yr⁻¹). Sequestration rates vary over time and with different technology and policy scenarios. The combined contribution of terrestrial sequestration over the next century ranges from 23 to 41 GtC.     

Jerusalem – Figment of the imagination

Jewish tradition refers to the city of Jerusalem in both abstract and concrete terms, celestial Jerusalem and earthly Jerusalem. The two are intricately bound up with each other and Jerusalem, the eternal capital city of the Jewish people, derives its powerful mystique, from its original appearance in Jewish history, although Biblical Jerusalem, the ancient city surrounded by hills, and modern Jerusalem, the capital city of Israel, surrounded by satellite urban appendages, lack geographical congruity. In general, this is geo-politically relevant given the potent sensitivities that most Jews in Israel and elsewhere have for the symbolic value of their ancient capital. Significantly, most of the Arab inhabitants the capital city of Israel, are not Israeli citizens and the vast majority of them refuse to participate in municipal elections, even though Israeli law allows non-citizens who are permanent residents to vote in local elections. That Israel permits several countries to maintain separate consulates, in the western and eastern parts of Israel's capital, indicates Israel's implicit recognition of a dual status in Jerusalem. After the 1967 war, while careful to avoid using the formal language of annexation, Israel generally considered that east Jerusalem and some surrounding areas had become part of Israel, when by Basic Law: Jerusalem, the Capital City, it was declared to be the united and eternal capital of the State of Israel. This paper examines these political and legal developments.     

A method for measuring ingestion rate of deposit feeders and its use with the polychaeteNereis succinea

In situ ingestion rates of some infaunal deposit feeders can be determined without collecting feces by labeling the sediment with fluorescent particles and using these to trace ingested material through the gut of the animals. This technique was applied to the polychaeteNereis succinea and showed that ingestion rate, expressed as material ingested per body weight, increased with temperature and decreased with body size. Total annual ingestion of sediment and detritus for aN. succinea population in a salt marsh near Beaufort, N.C., was estimated to be 5 kg of dry material m^?2, more than 4 times that reported for salt marsh epifaunal deposit feeders. *** DIRECT SUPPORT *** A01BY009 00005