Comparison of strain and magnetic fabrics in Dalradian rocks from the southwest Highlands of Scotland     

Jaswant Singh Rathore  Bernard Henry 《Journal of Structural Geology》1982,4(3):373-384

The magnetic fabrics of 235 samples from 31 localities in Argyllshire, Scotland were determined to study the development of the Caledonian tectonic fabric in the southwest Highlands of Scotland. The regional fabric indicates a strong NE-SW compressional foliation due to the primary deformational phases, which in parts has been overprinted by secondary deformations. A detailed comparison of the anisotropy data and the available strain data shows that the two fabric ellipsoids are co-axial, and that their axial mean ratios seem to be related by an empirical power relationship of the type: (for i = 1,2,3; j = 1,2,3 and i ≠ j) where χ_i and χ_j are orthogonal principal axes and l_i and l_j are the corresponding orthogonal principal strain axes. The exponent a for the sites from Scotland is 0.088 ± 0.017 compared with 0.142 ± 0.001 and 0.145 ± 0.005 found in the Caledonian slates of the English Lake District and the Welsh slate belt.  相似文献   

Oil Extraction and Benefit Sharing in an Illiberal Context: The Nenets and Komi-Izhemtsi Indigenous Peoples in the Russian Arctic     

Maria Tysiachniouk  Laura A. Henry  Machiel Lamers  Jan P. M. van Tatenhove 《社会与自然资源》2018,31(5):556-579

ABSTRACT

How can indigenous communities in illiberal regimes benefit from oil production? This paper compares the experience of two indigenous peoples in the Russian Arctic, the Nenets and the Komi-Izhemtsi, in their quest for environmental protection and the development of benefit-sharing arrangements with Lukoil, a Russian oil company. The Nenets people, recognized by the Russian state as indigenous, are marginalized political actors who identified a route to receiving compensation for loss of land and damage to the environment as well as economic benefits under the auspices of Russian law and Lukoil’s corporate policies. In contrast, the Komi-Izhemtsi, despite indigenous status in global institutions including the United Nations and the Arctic Council, are unrecognized as indigenous domestically and initially received no compensation. Their path to benefit sharing was more challenging as they partnered with local nongovernmental organizations and global environmentalists to pressure Lukoil to sign a benefit-sharing agreement. Ultimately, the comparison illustrates how transnational partnerships can empower indigenous people to gain benefits from natural resource exploitation even in illiberal political systems.  相似文献   

Vegetation cover change in the Upper Kings River basin of the Sierra Nevada detected using Landsat satellite image analysis     

Christopher Potter 《Climatic change》2015,131(4):635-647

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The round lake     

Henry W. Brandli  John W. Orndorff 《大气与海洋》2013,51(1):56-57

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Location of hydrogen atoms in hydronium jarosite     

Henry J. Spratt  Maxim Avdeev  Michael C. Pfrunder  John McMurtrie  Llew Rintoul  Wayde N. Martens 《Physics and Chemistry of Minerals》2014,41(7):505-517

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The Importance of Regional,System-Wide and Local Spatial Scales in Structuring Temperate Estuarine Fish Communities     

F. J. Valesini  J. R. Tweedley  K. R. Clarke  I. C. Potter 《Estuaries and Coasts》2014,37(3):525-547

An extensive literature base worldwide demonstrates how spatial differences in estuarine fish assemblages are related to those in the environment at (bio)regional, estuary-wide or local (within-estuary) scales. Few studies, however, have examined all three scales, and those including more than one have often focused at the level of individual environmental variables rather than scales as a whole. This study has identified those spatial scales of environmental differences, across regional, estuary-wide and local levels, that are most important in structuring ichthyofaunal composition throughout south-western Australian estuaries. It is the first to adopt this approach for temperate microtidal waters. To achieve this, we have employed a novel approach to the BIOENV routine in PRIMER v6 and a modified global BEST test in an alpha version of PRIMER v7. A combination of all three scales best matched the pattern of ichthyofaunal differences across the study area (ρ?=?0.59; P?=?0.001), with estuary-wide and regional scales accounting for about twice the variability of local scales. A shade plot analysis showed these broader-scale ichthyofaunal differences were driven by a greater diversity of marine and estuarine species in the permanently-open west coast estuaries and higher numbers of several small estuarine species in the periodically-open south coast estuaries. When interaction effects were explored, strong but contrasting influences of local environmental scales were revealed within each region and estuary type. A quantitative decision tree for predicting the fish fauna at any nearshore estuarine site in south-western Australia has also been produced. The estuarine management implications of the above findings are highlighted.  相似文献   

Relationship between solubility and solubility product: The roles of crystal sizes and crystallographic directions     

Chunfang Fan  Yang Chen  H. Henry Teng 《Geochimica et cosmochimica acta》2006,70(15):3820-3829

Grain size- and crystallographic direction-dependence are among the fundamental characteristics of crystal solubility. However, such important material properties are routinely ignored and solubility is often conveniently approximated by a solubility product. In this study, we attempt to outline the relationship between solubility and solubility product using thermodynamic arguments, and to provide observations that demonstrate the occurrence of circumstances where the solubility product cannot properly approximate crystal solubility. Theoretical analysis shows that solubility is always greater than solubility product, but the difference is inversely related to the grain size. Furthermore, the difference can be crystallographic direction specific if the total surface energy change upon the attachment of an individual growth unit is nonequivalent for each symmetrically unrelated crystal faces. In situ AFM experiments conducted on the cleavage face of calcite demonstrate that the steps exhibit direction- and length-dependent behavior. Specifically, the measured critical step lengths are consistent with the predicted inverse relationship to saturation states. Moreover, step retreat at and advance at are observed simultaneously in a narrow range of saturation at near equilibrium conditions, indicating the existence of direction specific solubility. Whereas these findings justify the rationale for approximating solubility by solubility product in cases where large crystals are concerned, the results imply that the size and direction effect should not be ignored if nanocrystal growth/dissolution is the subject of interest.  相似文献   

Influence of road network and population demand assumptions in evacuation modeling for distant tsunamis     

Kevin D. Henry  Nathan J. Wood  Tim G. Frazier 《Natural Hazards》2017,85(3):1665-1687

Tsunami evacuation planning in coastal communities is typically focused on local events where at-risk individuals must move on foot in a matter of minutes to safety. Less attention has been placed on distant tsunamis, where evacuations unfold over several hours, are often dominated by vehicle use and are managed by public safety officials. Traditional traffic simulation models focus on estimating clearance times but often overlook the influence of varying population demand, alternative modes, background traffic, shadow evacuation, and traffic management alternatives. These factors are especially important for island communities with limited egress options to safety. We use the coastal community of Balboa Island, California (USA), as a case study to explore the range of potential clearance times prior to wave arrival for a distant tsunami scenario. We use a first-in–first-out queuing simulation environment to estimate variations in clearance times, given varying assumptions of the evacuating population (demand) and the road network over which they evacuate (supply). Results suggest clearance times are less than wave arrival times for a distant tsunami, except when we assume maximum vehicle usage for residents, employees, and tourists for a weekend scenario. A two-lane bridge to the mainland was the primary traffic bottleneck, thereby minimizing the effect of departure times, shadow evacuations, background traffic, boat-based evacuations, and traffic light timing on overall community clearance time. Reducing vehicular demand generally reduced clearance time, whereas improvements to road capacity had mixed results. Finally, failure to recognize non-residential employee and tourist populations in the vehicle demand substantially underestimated clearance time.  相似文献   

Millennial Landscape Change in Jordan: Geoarchaeology and Cultural Ecology. Carlos E. Cordova, 2007, The University of Arizona Press,Tucson, Arizona,xix + 25pp., $55 (hardcover)     

Donald O. Henry 《Geoarchaeology》2008,23(3):422-424

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Hydro-mechanical analysis of rainfall-induced fines migration process within unsaturated soils     

Xiao-qin Lei  Zong-ji Yang  Si-ming He  En-long Liu  Henry Wong  Xin-po Li 《山地科学学报》2017,14(12):2603-2619

Seepage-induced fines migration under rainfall infiltration is a main cause leading to shallow failures in loose colluvial slopes. To describe the full process of fines migration within unsaturated soils during rainfall infiltration and the associated hydro-mechanical behaviors, a seepage-erosion-deformation coupled formulation is proposed in this paper. The governing equations proposed are implemented into a finite element code and used to investigate the influences of skeleton deformation on the rainfall infiltration process through unsaturated soil columns. The numerical results were presented in detail for a better understanding of the rainfall-induced fines migration process within unsaturated soils. Further, the obtained results are integrated into an infinite slope model for slope stability analysis. The results show that, the skeleton deformation will affect the rainfall infiltration rate and hence the timing of slope failures; meanwhile their influences are more evident if the fines deposition process is taken into account. Moreover, the slope stability could be reduced gradually due to the soil strength loss along with loss of fine particles. Therefore, particular attentions should be paid to analyzing the stability of soil slopes susceptible to internal erosion.  相似文献