Interest Groups,Federalism, and Water Quality in the Great Lakes: Chasing a Moving Target

Federalism often creates additional decisions for interest groups in determining how best to advocate for their policy recommendations in the legislative process. Should they focus their advocacy at the local, state, or national level of government? This article examines interest group behaviors in water quality policy in the Great Lakes region from 1960 to 2000. I evaluate the reasons for interest group decisions about which level of government to target, using historical analysis of Great Lakes water quality policy in the United States and Canada. The results of this analysis show that in many cases groups are influenced in their decision-making based on the level of government that has the greatest jurisdiction over the policy, supporting a neoinstitutional argument.     

A Rock‐Magnetic Quest for Possible Ore Sources for the Ancient Iron‐Smelting Industry in the Olkhon Region (Lake Baikal,Siberia)

Rock‐magnetic techniques were used to examine the topsoil layer of Kurma archaeological site (in the Olkhon region, on the north‐western coast of Lake Baikal, Siberia) in an effort to determine the possible sources of iron ores for iron‐smelting centres (at about the bc /ad boundary). Measurements have shown a magnetic enhancement of the topsoil due to magnetite grains resulting from weathering of strongly magnetic crystalline rocks. They have also revealed a preliminary picture of the distribution of strongly magnetic topsoils around the ancient iron‐smelting centres. Perhaps, in addition to traditional sources of raw materials, the ancient metallurgists used black sand talus as an ore deposit.     

Permeability changes in simulated granite faults during and after frictional sliding

Thermal–hydrological–mechanical coupling processes suggest that fault permeability should undergo dynamic change as a result of seismic slip. In igneous rocks, a fault's slip surface may have much higher permeability than the surrounding rock matrix and therefore operate as a conduit for fluids. We conducted laboratory experiments to investigate changes in fracture permeability (or transmissivity) of a fault in granite due to shear slip and cyclic heating and cooling. Our experiments showed that high initial fracture transmissivity (>10^?18 m³) was associated with a high friction coefficient and that transmissivity decreased during slip. We propose that this reduction in transmissivity reflects the presence of gouge in fracture voids, increasing the area of contact in the fault plane and reducing the hydraulic aperture. In contrast, when initial fracture transmissivity was low (<10^?18 m³), we observed that friction was lower and transmissivity increased during slip. The high transmissivity and high friction may be explained by large areas of bare rock being in contact on the slip surface. Slip velocity had little influence on the evolution of permeability, probably because gouge produced at different slip velocities had similar grain size distributions, or because gouge leaked from the slip surface. Transmissivity decreased with increasing temperature in heating tests, probably due to thermal expansion increasing normal stress on the fracture. Frictional heating did not influence transmissivity during the shearing tests.