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PACIFIC REGION

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New Zealand’s Alpine Fault (AF) ruptures quasi-periodically in large-magnitude earthquakes. Paleoseismological evidence suggests that about half of all recognized AF earthquakes terminated at the boundary between the Central and South Westland sections of the fault. There, fault geometry and the polarity of uplift change. The South Westland AF exhibits oblique-normal fault motion on a structure oriented 055/82SE that, for at least 35 km along strike, contains saponite-rich principal slip zone gouges. New hydrothermal friction experiments reveal that the saponite fault gouge is frictionally weak, exhibiting friction coefficients between =0.12 and =0.16 for a range of temperatures (T=25–210 C) and effective normal...
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We analyzed very-high-resolution imagery to assess status of Metrosideros polymorpha forests across an 83,603 hectare study area that experienced extensive canopy dieback in the 1970s on the eastern side of the island of Hawaii. Using GIS we generated 1170 virtual vegetation plots with a 100 m radius; 541 plots in areas mapped in 1977 with trees dead or mostly defoliated (dieback), and 629 plots in adjacent wet forest habitat, previously mapped as non-dieback condition. In each plot we estimated the percent of M. polymorpha trees dead or mostly defoliated, and percent of trees with healthy crowns. These results were combined with habitat data to produce a spatial model depicting probability of canopy dieback within...
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Several previously published reports and geographic information system (GIS) data layers were used to code information on site attributes for each assessment plot using the spatial join tool in ArcMap. This information was used for an analysis of dieback and non-dieback habitat characteristics. The results of this analysis are presented in this table which depicts the probability of heavy to severe canopy dieback occurring at some time at a particular 30 x 30 m pixel location within the study area.
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The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (NVASA), estimates of runoff and baseflow were determined for 312 streamflow-gaging stations from 1904 to 2015. Gages with complete water years (October to September) of continuous-streamflow record were used to partition streamflow into runoff and baseflow, which is that part of streamflow attributed to groundwater discharge. For each water year annual estimates of baseflow, runoff, and a base-flow...
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The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (NVASA), estimates of runoff and baseflow were determined for 312 streamflow-gaging stations from 1904 to 2015. Gages with complete water years (October to September) of continuous-streamflow record were used to partition streamflow into runoff and baseflow, which is that part of streamflow attributed to groundwater discharge. For each water year annual estimates of baseflow, runoff, and a base-flow...
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