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2009

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Articles 211 - 240 of 560

Full-Text Articles in Earth Sciences

Reply To The Comments Of W. Helland-Hansen On “Towards The Standardization Of Sequence Stratigraphy” By Catuneanu Et Al. [Earth-Sciences Review 92 (2009), Pp. 1–33], Octavian Catuneanu, V. Abreu, J. P. Bhattacharya, M. D. Blum, R. W. Dalrymple, P. G. Eriksson, Christopher R. Fielding, W. L. Fisher, W. E. Galloway, M. R. Gibling, K. A. Giles, J. M. Holbrook, R. Jordan, C. G. St.C. Kendall, B. Macurda, O. J. Martinsen, A. D. Miall, J. E. Neal, D. Nummedal, L. Pomar, H. W. Posamentier, B. R. Pratt, J. F. Sarg, K. W. Shanley, R. J. Steel, A. Strasser, M. E. Tucker, C. Winker May 2009

Reply To The Comments Of W. Helland-Hansen On “Towards The Standardization Of Sequence Stratigraphy” By Catuneanu Et Al. [Earth-Sciences Review 92 (2009), Pp. 1–33], Octavian Catuneanu, V. Abreu, J. P. Bhattacharya, M. D. Blum, R. W. Dalrymple, P. G. Eriksson, Christopher R. Fielding, W. L. Fisher, W. E. Galloway, M. R. Gibling, K. A. Giles, J. M. Holbrook, R. Jordan, C. G. St.C. Kendall, B. Macurda, O. J. Martinsen, A. D. Miall, J. E. Neal, D. Nummedal, L. Pomar, H. W. Posamentier, B. R. Pratt, J. F. Sarg, K. W. Shanley, R. J. Steel, A. Strasser, M. E. Tucker, C. Winker

Department of Earth and Atmospheric Sciences: Faculty Publications

We thank William Helland-Hansen for his compliments and feedback on our paper. We aimed to establish a consensus in sequence stratigraphy by using a neutral approach that focused on model-independent, fundamental concepts, because these are the ones common to various approaches. This search for common ground is what we meant by “standardization,” not the imposition of a strict, inflexible set of rules for the placement of sequence- stratigraphic surfaces. Our work is meant to eliminate the present state of methodological and nomenclatural confusion within sequence stratigraphy, which is largely the result of uncoordinated effort in the development of the method …


Geochemical And Petrographic Signatures From Marie Byrd Land And Larsen-B Ice Shelf Sediments : Implications For Provenance Tracing, Cathleen Lauren Dale May 2009

Geochemical And Petrographic Signatures From Marie Byrd Land And Larsen-B Ice Shelf Sediments : Implications For Provenance Tracing, Cathleen Lauren Dale

Theses, Dissertations and Culminating Projects

The goal of this study is to trace ice rafted debris in the Southern Ocean back to its most probable terrestrial source from the West Antarctic Ice Sheet (WAIS), East Antarctic Ice Sheet (EAIS), or the Antarctic Peninsula Ice Cap (APIC) in order to identify past ice sheet collapses in the geologic record. The bedrock in these areas have characteristic petrographic and geochemical signatures that are preserved in glacially transported and deposited sediment. These signatures may allow us to identify ice rafted debris and fine-grained sediment that originate from these three areas, which have undergone recent ice shelf retreat and …


Ridge Subduction Volcanism In The Zeballos Complex, Southern Patagonian Andes, Michael Joseph Dasilva May 2009

Ridge Subduction Volcanism In The Zeballos Complex, Southern Patagonian Andes, Michael Joseph Dasilva

Theses, Dissertations and Culminating Projects

The Zeballos Complex (47.0°S, 71.4°W) lies on the western side of Meseta del Lago Buenos Aires (MLBA) in the southern Andean backarc region, southeast of the Chile Triple Junction and east of ridge collision that occurred at 6 Ma. The Zeballos Complex is a bimodal, alkaline volcanic complex consisting of multiple lava flows, dikes, volcanic necks, and sub-volcanic intrusives that range from basalt to trachybasalt (47-50% SiO2; 5-7% Na2O+K2O; 3-7% MgO) to highly differentiated trachyandesite, trachydacite, and trachyte (58-65% SiO2; 8-12% Na2O+K2O). Intermediate compositions are relatively rare, but …


A Sedimentary Investigation Of Lineation Patterns Found In The Pinelands Of New Jersey, Jennifer Lynn Lapoma May 2009

A Sedimentary Investigation Of Lineation Patterns Found In The Pinelands Of New Jersey, Jennifer Lynn Lapoma

Theses, Dissertations and Culminating Projects

Late Pleistocene (-15,000 years ago) geomorphic processes in the Pinelands of southern New Jersey were investigated after odd lineations were found on an Electromagnetic Induction (EMI) survey during the construction of a runway expansion at Lakehurst Naval Air Engineering Station. These lineations roughly matched up with alternating high and low albedo lineations identified on a 1931 aerial photomosaic approximately 17 kilometer (km) south of Lakehurst Navy Base in Davensport Branch, New Jersey. These lineations were initially hypothesized to be relicts from strong katabic winds flowing off the Laurentide Ice Sheet that would have been capable of winnowing magnetic sands from …


Monitoring Protocol For Two New Jersey Ponds With Littoral Zone Vegetative Restoration, Michael Wilson May 2009

Monitoring Protocol For Two New Jersey Ponds With Littoral Zone Vegetative Restoration, Michael Wilson

Theses, Dissertations and Culminating Projects

Restoration projects are becoming more frequent and commonplace because of increased regulations on development to replace lost ecosystems. Many of these projects have marginal success and rarely achieve the desired results. The mistakes and oversights are sometimes in the planning stages, but more often are made during the installation, primarily due to improper horticultural technique, poor monitoring, education, or lack of follow-up maintenance. Wetland restoration is even more difficult, due to the variable hydrologic patterns and reliance on environmental conditions. The most difficult type of wetland plant to establish is the emergent aquatic that typically grows in water up to …


Capacitive Conductivity Logging And Electrical Stratigraphy In A High-Resistivity Aquifer, Boise Hydrogeophysical Research Site, C. Jonathan Mwenifumbo, Warren Barrash, Michael D. Knoll Apr 2009

Capacitive Conductivity Logging And Electrical Stratigraphy In A High-Resistivity Aquifer, Boise Hydrogeophysical Research Site, C. Jonathan Mwenifumbo, Warren Barrash, Michael D. Knoll

CGISS Publications and Presentations

We tested a prototype capacitive-conductivity borehole tool in a shallow, unconfined aquifer with coarse, unconsolidated sediments and very-low-conductivity water at the Boise Hydrogeophysical Research Site (BHRS). Examining such a high-resistivity system provides a good test for the capacitive- conductivity tool because the conventional induction- conductivity tool (known to have limited effectiveness in high-resistivity systems) did not generate expressive well logs at the BHRS. The capacitive-conductivity tool demonstrated highly repeatable, low-noise behavior but poor correlation with the induction tool in the lower-conductivity portions of the stratigraphy where the induction tool was relatively unresponsive. Singular spectrum analysis of capacitive- conductivity logs reveals …


Constraints On The Utility Of Mno2 Cartridge Method For The Extraction Of Radionuclides: A Case Study Using 234Th, M. Baskaran, P. W. Swarzenski, B. A. Biddanda Apr 2009

Constraints On The Utility Of Mno2 Cartridge Method For The Extraction Of Radionuclides: A Case Study Using 234Th, M. Baskaran, P. W. Swarzenski, B. A. Biddanda

Environmental Science and Geology Faculty Research Publications

Large volume (102–103 L) seawater samples are routinely processed to investigate the partitioning of particle reactive radionuclides and Ra between solution and size-fractionated suspended particulate matter. One of the most frequently used methods to preconcentrate these nuclides from such large volumes involves extraction onto three filter cartridges (a prefilter for particulate species and two MnO2-coated filters for dissolved species) connected in series. This method assumes that the extraction efficiency is uniform for both MnO2-coated cartridges, that no dissolved species are removed by the prefilter, and that any adsorbed radionuclides are not desorbed from …


The Furman Lake Restoration Plan, Wade Worthen Apr 2009

The Furman Lake Restoration Plan, Wade Worthen

Furman Lake Restoration Book Gallery

A presentation with text and images providing information on the history of the Furman Lake, it's environmental health decline throughout the years, and the lake's restoration. The presentation details the Furman Lake's problems, causes of these problems, and solutions. It describes Furman's progress in the restoration project, as well as it's goals for the future.


The Nebraska Sand Hills: Mid- To Late-Holocene Drought Variation And Landscape Stability Based On High-Resolution Lake Sediment Records, Jens Schmieder Apr 2009

The Nebraska Sand Hills: Mid- To Late-Holocene Drought Variation And Landscape Stability Based On High-Resolution Lake Sediment Records, Jens Schmieder

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

A high-resolution multi-proxy analysis was used to reconstruct moisture balance fluctuations spanning the last 6500 years and to investigate the origins of interdunal lakes in the central Sand Hills of Nebraska. Detailed paleoecological data from Beaver Lake, plus analyses from two nearby lakes, were integrated to reconstruct regional climate history. Six episodes of multi-centennial droughts occurred, with a dramatic change in overall mean state between 4000 and 3800 yr BP. An extensive low lake stand between 6500-5750 yr BP was likely predominantly climatically driven rather than geomorphically induced.

Paleohydrological reconstructions of five lakes in the Nebraska Sand Hills were compared …


Estimating The Effects Of Detection Heterogeneity And Overdispersion On Trends Estimated From Avian Point Counts, Matthew A. Etterson, Gerald J. Niemi, Nicholas P. Danz Apr 2009

Estimating The Effects Of Detection Heterogeneity And Overdispersion On Trends Estimated From Avian Point Counts, Matthew A. Etterson, Gerald J. Niemi, Nicholas P. Danz

United States Environmental Protection Agency: Publications

Point counts are a common method for sampling avian distribution and abundance. Although methods for estimating detection probabilities are available, many analyses use raw counts and do not correct for detectability. We use a removal model of detection within an N-mixture approach to estimate abundance trends corrected for imperfect detection. We compare the corrected trend estimates to those estimated from raw counts for 16 species using 15 years of monitoring data on three national forests in the western Great Lakes, USA. We also tested the effects of overdispersion by modeling both counts and removal mixtures under three statistical distributions: …


The Virtual Refraction: Useful Spurious Energy In Seismic Interferometry, Dylan Mikesell, Kasper Van Wijk, Alexander Calvert, Matthew M. Haney Apr 2009

The Virtual Refraction: Useful Spurious Energy In Seismic Interferometry, Dylan Mikesell, Kasper Van Wijk, Alexander Calvert, Matthew M. Haney

CGISS Publications and Presentations

Seismic interferometry is rapidly becoming an established technique to recover the Green’s function between receivers, but practical limitations in the source-energy distribution inevitably lead to spurious energy in the results. Instead of attempting to suppress all such energy, we use a spurious wave associated with the crosscorrelation of refracted energy at both receivers to infer estimates of subsurface parameters. We named this spurious event the virtual refraction. Illustrated by a numerical two-layer example, we found that the slope of the virtual refraction defines the velocity of the faster medium and that the stationary-phase point in the correlation gather provides the …


Sustainable Portland: Implementation Series 2, New England Environmental Finance Center Apr 2009

Sustainable Portland: Implementation Series 2, New England Environmental Finance Center

Climate Change

The Portland Municipal Climate Change Working Group prepared a report in March 2008 that outlined several recommendations as a commitment by the City to address greenhouse gas emissions (GHG) produced during daily municipal operations. The Municipal Climate Action Plan was written in partnership with Clean Air – Cool Planet and Portland officials, and acknowledges under Recommendation #2 that an employee energy efficiency program would provide significant positive impact on the City’s reduction of greenhouse gas emissions. Best practices from three cities show that focus on the greening of City Hall is critical in developing a program that promotes partnerships, community …


Markov Models For Linking Environments And Facies In Space And Time (Recent Arabian Gulf, Miocene Paratethys), Bernhard Riegl, Samuel J. Purkis Apr 2009

Markov Models For Linking Environments And Facies In Space And Time (Recent Arabian Gulf, Miocene Paratethys), Bernhard Riegl, Samuel J. Purkis

Marine & Environmental Sciences Faculty Books and Book Chapters

This special publication Perspectives in Carbonate Geology is a collection of papers most of which were presented at a symposium to honor the 80th birthday of Bob Ginsburg at the meeting of Geological Society of America in Salt Lake City in 2005. The majority of the papers in this publication are connected with the study of modern carbonate sediments. Bob Ginsburg pioneered the concept of comparative sedimentology - that is using the modern to compare to and relate to and understand the ancient. These studies are concerned with Bob's areas of passion: coral reefs and sea-level; submarine cementation and formation …


Droughtscape, Spring 2009, Kelly Smith Apr 2009

Droughtscape, Spring 2009, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

U.S. Drought Monitor Publishes Map 500!

Weakening La Niña May Mean Relief for Texas

Upcoming Workshops

Drought Impacts Worst in California, Texas

CoCoRaHS to Request Drought Impact Data, Too

NDMC Adds Researcher

K-12 Students Learn About Drought


The Storm 2.0 Project Next Generation Hurricane Data Collection, Santhana Krishnan Balaji Apr 2009

The Storm 2.0 Project Next Generation Hurricane Data Collection, Santhana Krishnan Balaji

Honors Capstones

No abstract provided.


Northern Prairie Wildlife Research Center Apr 2009

Northern Prairie Wildlife Research Center

United States Geological Survey: Publications

Contents:
Integrated Science for the Nation’s Northern Great Plains
Core Science Capabilities
Center Expertise
Highlights of Current Research Program
Our Mission
Locations of the Center and Duty Stations


Using Gis To Locate Areas For Growing Quality Coffee In Honduras, Ellen Mickle Apr 2009

Using Gis To Locate Areas For Growing Quality Coffee In Honduras, Ellen Mickle

Department of Environmental Studies: Undergraduate Student Theses

Abstract Small-scale coffee producers worldwide remain vulnerable to price fluctuations after the 1999-2003 coffee crisis. One way to increase small-scale farmer economic resilience is to produce a more expensive product, such as quality coffee. There is growing demand in coffee-producing and coffee-importing countries for user-friendly tools that facilitate the marketing of quality coffee. The purpose of this study is to develop a prototypical quality coffee marketing tool in the form of a GIS model that identifies regions for producing quality coffee in a country not usually associated with quality coffee, Honduras. Maps of areas for growing quality coffee were produced …


High Time Resolution Pfisr And Optical Observations Of Naturally Enhanced Ion Acoustic Lines, R G. Michell, K A. Lynch, C J. Heinselman, H C. Stenbaek-Nielsen Apr 2009

High Time Resolution Pfisr And Optical Observations Of Naturally Enhanced Ion Acoustic Lines, R G. Michell, K A. Lynch, C J. Heinselman, H C. Stenbaek-Nielsen

Dartmouth Scholarship

Observations of naturally enhanced ion acoustic lines (NEIALs) taken with the Poker Flat Incoherent Scatter Radar (PFISR) using a mode with very high time resolution are presented. The auroral event took place over Poker Flat, Alaska on 8 February 2007 at 09:35 UT (∼22:00 MLT), and the radar data are complemented by common-volume high- resolution auroral imaging. The NEIALs occurred during only one of the standard 15-s integration periods. The raw data of this time show very intermittent NEIALs which oc- cur only during a few very short time intervals (≤1 s) within the 15-s period. The time sampling of …


Low-Level Pharmaceuticals And Personal Care Products In The Waters Of Michigan, Lisa M. Anderson Apr 2009

Low-Level Pharmaceuticals And Personal Care Products In The Waters Of Michigan, Lisa M. Anderson

Dissertations

The results of this research are the product of a two year study funded by the Michigan Department of Environmental Quality with monies from the Clean Michigan Initiative. Low-level (part per billion range) pharmaceuticals and personal care products (PPCPs) in the waters of Michigan were investigated. Five rivers in the State were sampled; including the Clinton, Grand, Kalamazoo, Muskegon, and Saginaw. Groundwater samples were obtained from two shallow municipal water wells also; one on the Grand River and one on the Kalamazoo River. The wells were sampled to determine if PPCPs in the river water were being drawn in by …


Inquiry-Based Introductory Earth Science Laboratory Using Survey Equipment, Tamie J. Jovanelly Apr 2009

Inquiry-Based Introductory Earth Science Laboratory Using Survey Equipment, Tamie J. Jovanelly

Georgia Educational Researcher

A laboratory assignment entitled was developed to give high-school students an opportunity to collect, analyze, and interpret data after they have been introduced to topographic maps and associated terminology. Survey equipment (automatic level, graduated staff, and tripod) is used to collect data with the goal of creating a topographic profile along a linear transect on campus. This assignment sets itself apart from traditional introductory earth science labs because the students are using instrumentation to collect data, rather than having a data set provided for them. The benefits of this assignment include: 1) further understanding of topographic maps, 2) practice with …


Fluvial-Estuarine Reinterpretation Of Large, Isolated Sandstone Bodies In Epicontinental Cyclothems, Upper Pennsylvanian, Northern Midcontinent, Usa, And Their Significance For Understanding Late Paleozoic Sea-Level Fluctuations, Steven A. Fischbein, R. Matthew Joeckel, Christopher R. Fielding Apr 2009

Fluvial-Estuarine Reinterpretation Of Large, Isolated Sandstone Bodies In Epicontinental Cyclothems, Upper Pennsylvanian, Northern Midcontinent, Usa, And Their Significance For Understanding Late Paleozoic Sea-Level Fluctuations, Steven A. Fischbein, R. Matthew Joeckel, Christopher R. Fielding

Department of Earth and Atmospheric Sciences: Faculty Publications

The Upper Pennsylvanian Indian Cave Sandstone (ICS) in southeastern Nebraska is herein reinterpreted as three multistory incised valley fills and one single-storey channel fill, altogether representing at least two different intervals of time. ICS lithosomes are linear bodies, as much as 2000 m wide and 30 m thick, incised into pre-existing cyclothems, and have relatively steep sides and flat bases. They include crudely fining-upwards successions of trough cross-bedded sandstones, interpreted as tidally-influenced fluvial deposits, overlain by upper estuarine heterolithic facies, with local coals, and a restricted trace fossil assemblage. The vertical facies succession suggests sediment accumulation in a regime of …


Using Pedotransfer Functions In Vadose Zone Models For Estimating Groundwater Recharge In Semiarid Regions, Tiejun Wang, Vitaly A. Zlotnik, Jirka Šimunek, Marcel G. Schaap Apr 2009

Using Pedotransfer Functions In Vadose Zone Models For Estimating Groundwater Recharge In Semiarid Regions, Tiejun Wang, Vitaly A. Zlotnik, Jirka Šimunek, Marcel G. Schaap

Department of Earth and Atmospheric Sciences: Faculty Publications

Process-based vadose zone models are becoming common tools for evaluating spatial distributions of groundwater recharge (GR), but their applications are restricted by complicated parameterizations, especially because of the need for highly nonlinear and spatially variable soil hydraulic characteristics (SHCs). In an attempt to address the scarcity of field SHC data, pedotransfer functions (PTF) were introduced in earlier attempts to estimate SHCs. However, the accuracy of this method is rarely questioned in spite of significant uncertainties of PTF-estimated SHCs. In this study, we investigated the applicability of coupling vadose zone models and PTFs for evaluating GR in sand and loamy sand …


A Bio-Optical Model For Syringodium Filiforme Canopies, Margaret A. Stoughton Apr 2009

A Bio-Optical Model For Syringodium Filiforme Canopies, Margaret A. Stoughton

OES Theses and Dissertations

Seagrasses are significant ecological and biogeochemical agents in shallow water ecosystems throughout the world. In many regions, seagrass meadows occupy a sufficient fraction of the coastal zone, and generate optical signatures that can be observed from space. Bio-optical models of light absorption and scattering by submerged plant canopies for certain species such as Thalassia testudinum and Zostera marina have successfully modeled the plane irradiance distribution and photosynthesis within the submerged canopies. Syringodium filiforme differs &om T. testudinttm and Z marina, in leaf morphology and canopy architecture. The objective of this study was to develop a radiative transfer model that …


Antarctic Drilling Recovers Stratigraphic Records From The Continental Margin, David M. Harwood, Fabio Florindo, Franco M. Talarico, Richard Levy, Gerhard Kuhn, Tim Naish, F. Niessen, Ross Powell, Alex Pyne, Gary Wilson Mar 2009

Antarctic Drilling Recovers Stratigraphic Records From The Continental Margin, David M. Harwood, Fabio Florindo, Franco M. Talarico, Richard Levy, Gerhard Kuhn, Tim Naish, F. Niessen, Ross Powell, Alex Pyne, Gary Wilson

Department of Earth and Atmospheric Sciences: Faculty Publications

The Antarctic Geological Drilling (ANDRILL) program—a collaboration between Germany, Italy, New Zealand, and the United States that is one of the larger programs endorsed by the International Polar Year (IPY; http:// www .ipy .org)—successfully completed the drilling phase of the Southern McMurdo Sound (SMS) Project in December 2007. This second drill core of the program’s campaign in the western Ross Sea, Antarctica, complements the results of the first drilling season [Naish et al., 2007] by penetrating deeper into the stratigraphic section in the Victoria Land Basin and extending the recovered time interval back to approximately 20 million years ago.

The …


Crop Updates - 2009 Katanning, Murray Scholz, Peter Newman, Glenn Adam, Trevor Bell, Michael Whitehead, W. K. Anderson, Chris Gazey, J. Andrew, R. Pearce, Bill Bowden, Wayne Pluske, Jeremy Lemon, D. C. Edmeades, J. J. Russell, Blakely H. Paynter, David Ferris, Abul Hashen, Catherine Borger, Stephen B. Powels, Qin Yu, Mechelle Owen, Roberto Busi, Sudheesh Manalil, Sally Peltzer, David Minkey, Raj Malik Mar 2009

Crop Updates - 2009 Katanning, Murray Scholz, Peter Newman, Glenn Adam, Trevor Bell, Michael Whitehead, W. K. Anderson, Chris Gazey, J. Andrew, R. Pearce, Bill Bowden, Wayne Pluske, Jeremy Lemon, D. C. Edmeades, J. J. Russell, Blakely H. Paynter, David Ferris, Abul Hashen, Catherine Borger, Stephen B. Powels, Qin Yu, Mechelle Owen, Roberto Busi, Sudheesh Manalil, Sally Peltzer, David Minkey, Raj Malik

Crop Updates

This session covers seventeen papers from different authors

  1. GM canola – How will it affect the way I farm? Murray Scholz, 2008 Nuffield scholar, Southern NSW

  2. Eight years of IWM smashes tyegrass seed banks by 98% over 31 focus paddocks, Peter Newman, Glenn Adam & Trevor Bell, Department of Agriculture and Food

  3. The global economic climate and impacts on agriculture, profile on Michael Whitehead Rabobank New York

  4. Lessons from five years of cropping systems research, W.K. Anderson, Department of Agriculture and Food

  5. Case study of a 17year old agricultural lime trial, C. Gazey, Department of Agriculture …


Kinematic Behavior Of Southern Alaska Constrained By Westward Decreasing Postglacial Slip Rates On The Denali Fault, Alaska, A.-S. Mériaux, K. Sieh, R. C. Finkel, Charles M. Rubin, M. H. Taylor, A. J. Meltzner, F. J. Ryerson Mar 2009

Kinematic Behavior Of Southern Alaska Constrained By Westward Decreasing Postglacial Slip Rates On The Denali Fault, Alaska, A.-S. Mériaux, K. Sieh, R. C. Finkel, Charles M. Rubin, M. H. Taylor, A. J. Meltzner, F. J. Ryerson

All Faculty Scholarship for the College of the Sciences

Long‐term slip rates for the Denali Fault in southern Alaska are derived using 10Be cosmogenic radionuclide (CRN) dating of offset glacial moraines at two sites. Correction of 10Be CRN model ages for the effect of snow shielding uses historical, regional snow cover data scaled to the site altitudes. To integrate the time variation of snow cover, we included the relative changes in effective wetness over the last 11 ka, derived from lake‐level records and δ 18O variations from Alaskan lakes. The moraine CRN model ages are normally distributed around an average of 12.1 ± 1.0 ka (n …


Hydrometeor-Enhanced Tephra Sedimentation: Constraints From The 18 May 1980 Eruption Of Mount St. Helens, Adam J. Durant, William I. Rose, A. M. Sarna-Wojcicki, S. Carey, A. C. M. Volentik Mar 2009

Hydrometeor-Enhanced Tephra Sedimentation: Constraints From The 18 May 1980 Eruption Of Mount St. Helens, Adam J. Durant, William I. Rose, A. M. Sarna-Wojcicki, S. Carey, A. C. M. Volentik

Department of Geological and Mining Engineering and Sciences Publications

Uncertainty remains on the origin of distal mass deposition maxima observed in many recent tephra fall deposits. In this study the link between ash aggregation and the formation of distal mass deposition maxima is investigated through reanalysis of tephra fallout from the Mount St. Helens 18 May 1980 (MSH80) eruption. In addition, we collate all the data needed to model distal ash sedimentation from the MSH80 eruption cloud. Four particle size subpopulations were present in distal fallout with modes at 2.2 Φ, 4.2 Φ, 5.9 Φ, and 8.3 Φ. Settling rates of the coarsest subpopulation closely matched predicted single-particle terminal …


Variable Uplift From Quaternary Folding Along The Northern Coast Of East Timor, Based On U-Series Age Determinations Of Coral Terraces, Nicole L. Cox Mar 2009

Variable Uplift From Quaternary Folding Along The Northern Coast Of East Timor, Based On U-Series Age Determinations Of Coral Terraces, Nicole L. Cox

Theses and Dissertations

Surveys of emergent terraces and U-series ages for ten sites along the coast of East Timor provide estimates of late Quaternary differential vertical strain in the most mature region of the Banda Arc-continent collision complex. Over a distance of ~180 km vertical displacement rates vary between 0.0 and 1.6 meters per 1000 years for the last 150,000 years. Two models of terrace formation (constructional and erosional) are applied to interpret terrace ages from coral ages and to estimate uplift rates. The highest uplift rates are from three sites over a distance of 15 km along the coast. Uplift rates were …


Fisheries Research Contract Report No. 20 - Risk Assessment Of The Record Brook Inter-Basin Water Transfer Scheme To The Aquatic Fauna Of The Donnelly And Warren Rivers, M. De Graaf, D. L. Morgan, S. J. Beatty, C. W. Hugh Mar 2009

Fisheries Research Contract Report No. 20 - Risk Assessment Of The Record Brook Inter-Basin Water Transfer Scheme To The Aquatic Fauna Of The Donnelly And Warren Rivers, M. De Graaf, D. L. Morgan, S. J. Beatty, C. W. Hugh

Fisheries Research Contract Reports

Report to the Water Corporation of Western Australia

This report describes the fishes and freshwater crayfishes of the Donnelly and Warren River catchments and provides a risk assessment to these fauna of the proposed extraction of water from Record Brook (tributary of the Donnelly River) and subsequent transfer to Scabby Gully Dam (Warren River catchment). The proposed location of the structure in Record Brook is at the gauging station ~1 km upstream from the confluence with the Donnelly River. The project aims to divert peak flows in the winter and spring flow period, transferring around 500 ML each year. The …


Role Of Forward Model In Surface-Wave Studies To Delineate A Buried High-Velocity Layer, Xiaohui Jin, Barbara Luke, Carlos Calderon-Macias Mar 2009

Role Of Forward Model In Surface-Wave Studies To Delineate A Buried High-Velocity Layer, Xiaohui Jin, Barbara Luke, Carlos Calderon-Macias

Civil and Environmental Engineering and Construction Faculty Research

Procedures are tested and compared for processing Rayleigh surface wave data to obtain one-dimensional shear wave velocity profiles for a hypothetical site that contains a buried high-velocity layer (HVL). The main purpose of such an investigation would be to discriminate and characterize the HVL. When target dispersion curves are derived from synthetic time histories, for the most part, the HVL is better identified when profiles are inverted using only the fundamental mode of Rayleigh wave propagation, rather than a more compatible but more complex forward model. The outcomes imply that in practice, a simple forward model might be more successful …