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2004

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Articles 91 - 120 of 3873

Full-Text Articles in Physical Sciences and Mathematics

Hyperbolic Sets That Are Not Locally Maximal, Todd L. Fisher Dec 2004

Hyperbolic Sets That Are Not Locally Maximal, Todd L. Fisher

Faculty Publications

This paper addresses the following topics relating to the structure of hyperbolic sets: First, hyperbolic sets that are not contained in locally maximal hyperbolic sets. Second, the existence of a Markov partition for a hyperbolic set. We construct new examples of hyperbolic sets which are not contained in locally maximal hyperbolic sets. The first example is robust under perturbations and can be constructed on any compact manifold of dimension greater than one. The second example is robust, topologically transitive, and constructed on a 4-dimensional manifold. The third example is volume preserving and constructed on R4. We show that every hyperbolic …


Wave Scattering From Infinite Cylindrical Obstacles Of Arbitrary Cross-Section, Matthew B. Weber Dec 2004

Wave Scattering From Infinite Cylindrical Obstacles Of Arbitrary Cross-Section, Matthew B. Weber

Theses and Dissertations

In this work the scattering of an incident plane wave propagating along a plane perpendicular to the xy-plane is studied. The wave is scattered from an infinitely long cylindrical object of arbitrary cross-section. Due to the arbitrary geometry of the obstacle, a finite differences numerical method is employed to approximate the solution of the scattering problems. The wave equation is expressed in terms of generalized curvilinear coordinates. Boundary conforming grids are generated using elliptic grid generators. Then, a explicit marching in time scheme is implemented over these grids. It is found that as time grows the numerical solution converges to …


The Proportional Odds Model For Assessing Rater Agreement With Multiple Modalities, Elizabeth Garrett-Mayer, Steven N. Goodman, Ralph H. Hruban Dec 2004

The Proportional Odds Model For Assessing Rater Agreement With Multiple Modalities, Elizabeth Garrett-Mayer, Steven N. Goodman, Ralph H. Hruban

Johns Hopkins University, Dept. of Biostatistics Working Papers

In this paper, we develop a model for evaluating an ordinal rating systems where we assume that the true underlying disease state is continuous in nature. Our approach in motivated by a dataset with 35 microscopic slides with 35 representative duct lesions of the pancreas. Each of the slides was evaluated by eight raters using two novel rating systems (PanIN illustrations and PanIN nomenclature),where each rater used each systems to rate the slide with slide identity masked between evaluations. We find that the two methods perform equally well but that differentiation of higher grade lesions is more consistent across raters …


Cross-Study Validation And Combined Analysis Of Gene Expression Microarray Data, Elizabeth Garrett-Mayer, Giovanni Parmigiani, Xiaogang Zhong, Leslie Cope, Edward Gabrielson Dec 2004

Cross-Study Validation And Combined Analysis Of Gene Expression Microarray Data, Elizabeth Garrett-Mayer, Giovanni Parmigiani, Xiaogang Zhong, Leslie Cope, Edward Gabrielson

Johns Hopkins University, Dept. of Biostatistics Working Papers

Investigations of transcript levels on a genomic scale using

hybridization-based arrays led to formidable advances in our

understanding of the biology of many human illnesses. At the same time, these investigations have generated controversy, because of the probabilistic nature of the conclusions, and the surfacing of noticeable discrepancies between the results of studies addressing the same biological question. In this article we present simple and effective data analysis and visualization tools for gauging the degree to which

the finding of one study are reproduced by others, and for integrating multiple studies in a single analysis.

We describe these approaches in …


Atrazine Runoff In The Blue River Basin: Geomorphology, Rainfall, And Agronomic Practices, Kundan Dhakal Dec 2004

Atrazine Runoff In The Blue River Basin: Geomorphology, Rainfall, And Agronomic Practices, Kundan Dhakal

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Atrazine concentrations in the Big Blue River Basin (BRB) in Nebraska and Kansas periodically exceed the U.S. EPA Maximum Contaminant Level (MCL) of 3 µg L-1. The present study is focused on watershed variables influencing surface runoff of atrazine. The assessment includes the impact of corn and sorghum planting progress (indicating atrazine application), rainfall, antecedent soil water content, and soil restrictive layer on stream-measured weekly atrazine load in independent BRB subwatersheds for 1997 - 2004. Maximum atrazine loading occurred after most of the corn had been planted but during sorghum planting from mid-May to early June, immediately following …


Manganese Oxide Thin Films Prepared By Nonaqueous Sol-Gel Processing: Preferential Formation Of Birnessite, Stanton Ching, Steven M. Hughes, Timothy P. Gray, Eric J. Welch Dec 2004

Manganese Oxide Thin Films Prepared By Nonaqueous Sol-Gel Processing: Preferential Formation Of Birnessite, Stanton Ching, Steven M. Hughes, Timothy P. Gray, Eric J. Welch

Chemistry Faculty Publications

High quality manganese oxide thin films with smooth surfaces and even thicknesses have been prepared with a nonaqueous sol–gel process involving reduction of tetraethylammonium permanganate in methanol. Spin-coated films have been cast onto soft glass, quartz, and Ni foil substrates, with two coats being applied for optimum crystallization. The addition of alkali metal cations as dopants results in exclusive formation of the layered birnessite phase. By contrast, analogous reactions in bulk sol–gel reactions yield birnessite, tunneled, and spinel phases depending on the dopant cation. XRD patterns confirm the formation of well-crystallized birnessite. SEM images of Li-, Na-, and K–birnessite reveal …


Spectral Degree Of Coherence Of A Random Three-Dimensional Electromagnetic Field, Olga Korotkova, Emil Wolf Dec 2004

Spectral Degree Of Coherence Of A Random Three-Dimensional Electromagnetic Field, Olga Korotkova, Emil Wolf

Physics Articles and Papers

The complex spectral degree of coherence of a general random, statistically stationary electromagnetic field is introduced in a manner similar to the way it is defined for a beamlike field, namely, by means of Young’s interference experiment. Both its modulus and its phase are measurable. We illustrate the definition by applying it to blackbody radiation emerging from a cavity. The results are of particular interest for near-field optics.


What Does Height Really Mean? Part I: Introduction, Thomas H. Meyer, Daniel R. Roman, David B. Zilkoski Dec 2004

What Does Height Really Mean? Part I: Introduction, Thomas H. Meyer, Daniel R. Roman, David B. Zilkoski

Thomas H. Meyer's Peer-reviewed Articles

This is the first paper in a four-part series considering the fundamental question, “what does the word height really mean?” National Geodetic Survey (NGS) is embarking on a height modernization program in which, in the future, it will not be necessary for NGS to create new or maintain old orthometric height benchmarks. In their stead, NGS will publish measured ellipsoid heights and computed Helmert orthometric heights for survey markers. Consequently, practicing surveyors will soon be confronted with coping with these changes and the differences between these types of height. Indeed, although “height’” is a commonly used word, an exact definition …


Coral Reef Ecosystem Restoration Off Southeast Florida, David S. Gilliam, Walter Jaap, Richard E. Dodge, Elizabeth Glynn Fahy, Jamie A. Monty, Brian K. Walker, Lauren F. Shuman, B. D. Ettinger, Daniel P. Fahy, Shaun M. Gill, Richard Shaul Dec 2004

Coral Reef Ecosystem Restoration Off Southeast Florida, David S. Gilliam, Walter Jaap, Richard E. Dodge, Elizabeth Glynn Fahy, Jamie A. Monty, Brian K. Walker, Lauren F. Shuman, B. D. Ettinger, Daniel P. Fahy, Shaun M. Gill, Richard Shaul

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Significant coral reef community development along the eastern shelf of the United States continues northward of the Florida Keys through Miami-Dade, Broward, Palm Beach, and Martin Counties, Florida (to Latitude 27° N). These Southeast Florida high-latitude coral communities have approximately 30 species of stony corals, stony coral coverage of 2-3%, and a diverse assemblage of reef gorgonians, sponges, and fishes.

This system lays within 3 km of the coast offshore a highly urbanized area comprising a population of over 5 million people (the population of Broward County alone exceeds 1.7 million). These reefs are important economic assets: a 2001 economic …


A Statistical Study Of The Global Structure Of The Ring Current, A. M. Jorgensen, Harlan E. Spence, W. J. Hughes, H. J. Singer Dec 2004

A Statistical Study Of The Global Structure Of The Ring Current, A. M. Jorgensen, Harlan E. Spence, W. J. Hughes, H. J. Singer

Physics & Astronomy

[1] In this paper we derive the average configuration of the ring current as a function of the state of the magnetosphere as indicated by the Dst index. We sort magnetic field data from the Combined Release and Radiation Effects Satellite (CRRES) by spatial location and by the Dst index in order to produce magnetic field maps. From these maps we calculate local current systems by taking the curl of the magnetic field. We find both the westward (outer) and the eastward (inner) components of the ring current. We find that the ring current intensity varies linearly with Dst as …


The John Muir Newsletter, Winter 2004/2005, The John Muir Center For Environmental Studies Dec 2004

The John Muir Newsletter, Winter 2004/2005, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

Newsletter UNiVfeftsnY or the Pacific, Stockton, cA Volume 15, Number 1 Winter 2004/2005 Black Sheep of the in Muir's Motivations for Yosemite National hi] Jeimij Krone ERRA: GREAT! Park (he expansive 760,000-acre Yosemite National Park consists of meadows, forests, and mountains that presently awe over three million visitors annually.1 Yosemite Valley became the second national park in 1890 after an intense nationwide conflict that most tourists neglect to acknowledge when scaling the glacial-smoothened sides of Half Dome or navigating woodlands of sugar pines and giant sequoias. John Muir, a foremost figure in the early conservation movement, spearheaded the proposal and …


Agenda: Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center Dec 2004

Agenda: Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center

Introduction to the Legal Foundation of Federal Land Management (December 1-3)

Materials prepared for the course held at the National Center for Atmospheric Research in Boulder, Colorado on December 1-3, 2004

Course instructors: Charles Wilkinson; Sarah Krakoff; Kathryn Mutz; Ann Morgan; Maggie Fox

Contents:

Introduction -- Agenda -- Summaries of laws -- Case studies. Travel management; Oil and gas development; Timber/fuels reduction -- How to influence agency decision makers -- Natural resource related legal and policy resources for the non-legal professional


Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center Dec 2004

Introduction To The Legal Foundation Of Federal Land Management, University Of Colorado Boulder. Natural Resources Law Center

Introduction to the Legal Foundation of Federal Land Management (December 1-3)

1 v. (various pagings) : ill., maps ; 28 cm

Materials prepared for the course held at the National Center for Atmospheric Research in Boulder, Colorado on December 1-3, 2004

Course instructors: Charles Wilkinson; Sarah Krakoff; Kathryn Mutz; Ann Morgan; Maggie Fox

Contents:

Introduction -- Agenda -- Summaries of laws -- Case studies. Travel management; Oil and gas development; Timber/fuels reduction -- How to influence agency decision makers -- Natural resource related legal and policy resources for the non-legal professional


High Statistics Search For The Θ+ (1.54) Pentaquark State, M. J. Longo, Timothy Holmstrom, Hypercp Collaboration Dec 2004

High Statistics Search For The Θ+ (1.54) Pentaquark State, M. J. Longo, Timothy Holmstrom, Hypercp Collaboration

Chemistry & Physics Faculty Publications

We have searched for θ+(1.54)→K0p decays using data from the 1999 run of the HyperCP experiment at Fermilab. We see no evidence for a narrow peak in the KS0p mass distribution near 1.54  GeV/c among 106 000 KS0p candidates, and obtain an upper limit for the fraction of θ+(1.54) to KS0p candidates of


Effects Of Signal Processing And Antenna Frequency On The Geostatistical Structure Of Ground-Penetrating Radar Data, Greg A. Oldenborger, Michael D. Knoll, Warren Barrash Dec 2004

Effects Of Signal Processing And Antenna Frequency On The Geostatistical Structure Of Ground-Penetrating Radar Data, Greg A. Oldenborger, Michael D. Knoll, Warren Barrash

CGISS Publications and Presentations

Recent research has suggested that the geostatistical structure of ground-penetrating radar data may be representative of the spatial structure of hydraulic properties. However, radar images of the subsurface can change drastically with application of signal processing or by changing the signal frequency. We perform geostatistical analyses of surface radar reflection profiles in order to investigate the effects of data processing and antenna frequency on the semivariogram structure of radar reflection amplitudes. Surface radar reflection data collected at the Boise Hydrogeophysical Research Site illustrate the processing- and antenna-dependence of radar semivariograms for a fluvial, cobble-and-sand aquifer. Compensating for signal attenuation and …


South East Humps Focus Catchment Report, A Hollick Dec 2004

South East Humps Focus Catchment Report, A Hollick

Resource management technical reports

This report provides a record of the activities carried out by the Lockhart Focus Support Team and the Catchment Group. It covers the results of the investigations and a summary of the group's catchment plan for the South East Humps Catchment east of Hyden in Western Australia. It covers the current best available information on soils, groundwater hydrology, surface water control, alternative crops and pastures, and revegetation options.


The Other Side Of Silence: Rachel Carson’S Views Of Animals, Marc Bekoff, Jan Nystrom Dec 2004

The Other Side Of Silence: Rachel Carson’S Views Of Animals, Marc Bekoff, Jan Nystrom

Animal Welfare Collection

The publication of Rachel Carson’s Silent Spring in 1962 is widely regarded as one of the major events that launched the modern environmental movement. Silent Spring is a compelling blend of stories, natural history, human values, and biological facts. In this essay we consider Carson’s attitude toward animals in Silent Spring and in other texts. Despite the facts that she was raised to love Nature and animals, little direct attention has been given to Carson’s views about our moral responsibilities to, and the moral standing of animals. Carson favored responsible stewardship, was more of an animal welfarist and environmentalist/conservation biologist …


Orographic Midlatitude Cyclone Modification: An Appalachian Study, Andrew Douglas Augustine Dec 2004

Orographic Midlatitude Cyclone Modification: An Appalachian Study, Andrew Douglas Augustine

All-Inclusive List of Electronic Theses and Dissertations

Forecasting weather within cyclonic systems is increasingly complicated and problematic when the cyclone is modified as it passes over a mountain range. Although much study has been devoted to orographic effects, the degree of influence exerted upon midlatitude cyclones by the undersized Appalachian Mountains has not been fully established. The fundamental goal of this research was to investigate the relationships between the orography of the Appalachian region and three inherent properties exhibited by midlatitude cyclones traversing the region including intensity, movement speed, and heading. The methodology used in this study integrates GIS within a climatological analysis. Initially, a midlatitude surface …


Newton, Maclaurin, And The Authority Of Mathematics, Judith V. Grabiner Dec 2004

Newton, Maclaurin, And The Authority Of Mathematics, Judith V. Grabiner

Pitzer Faculty Publications and Research

Sir Isaac Newton revolutionized physics and astronomy in his Principia. How did he do it? Would his method work on any area of inquiry, not only in science, but also about society and religion? We look at how some Newtonians, most notably Colin Maclaurin, combined sophisticated mathematical modeling and empirical data in what has come to be called the "Newtonian Style." We argue that this style was responsible not only for Maclaurin’s scientific success but for his ability to solve problems ranging from taxation to insurance to theology. We show how Maclaurin’s work strengthened the prestige of Newtonianism and …


Techniques For Restoring Gorgonians To Coral Reef Injury Areas, Lauren F. Shuman, David S. Gilliam, Richard E. Dodge, B. D. Ettinger, Daniel P. Fahy, Elizabeth Glynn Fahy, Shaun M. Gill, Jamie A. Monty, Brian K. Walker Dec 2004

Techniques For Restoring Gorgonians To Coral Reef Injury Areas, Lauren F. Shuman, David S. Gilliam, Richard E. Dodge, B. D. Ettinger, Daniel P. Fahy, Elizabeth Glynn Fahy, Shaun M. Gill, Jamie A. Monty, Brian K. Walker

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Great attention and energy has been spent investigating reattachment techniques for dislodged and fragmented scleractinian corals; however there has been a lack of controlled experimentation on how to restore dislodged gorgonians following a disturbance event, such as a ship grounding. Unfortunately, reef damage events occur frequently off southeast Florida. As an example, since 1998 at least five freighters have grounded on the reefs near Ft. Lauderdale, Broward County. These freighters dislodged many scleractinian and gorgonian corals and often destroyed thousands of square feet of reef habitat. After these events, restoration efforts concentrated on stabilizing loose debris and rubble, and reattaching …


Discovery Of Co Gas In The Inner Disk Of Tw Hydrae, Terrence W. Rettig, Joe Haywood, Theodore Simon, Sean D. Brittain, Erika Gibb Dec 2004

Discovery Of Co Gas In The Inner Disk Of Tw Hydrae, Terrence W. Rettig, Joe Haywood, Theodore Simon, Sean D. Brittain, Erika Gibb

Publications

We report the detection of rovibrationally excited CO emission from the inner disk of the classical T Tauri star (cTTS) TW Hya. We observe ~6 × 1021 g of CO gas with a rotational temperature of 430 ± 40 K. The linearity of the excitation plot suggests that the CO is optically thin. Atypical for cTTSs, hot CO was not detected, implying that TW Hya has cleared its inner disk region out to a radial distance of ~0.5 AU. We discuss implications for the structure of the disk as it relates to replenishment and planet formation.


Seasonal Variations Of The Gravity Wave Momentum Flux In The Antarctic Mesosphere And Lower Thermosphere, P. J. Espy, G. O.L. Jones, G. R. Swenson, J. Tang, Michael J. Taylor Dec 2004

Seasonal Variations Of The Gravity Wave Momentum Flux In The Antarctic Mesosphere And Lower Thermosphere, P. J. Espy, G. O.L. Jones, G. R. Swenson, J. Tang, Michael J. Taylor

All Physics Faculty Publications

Airglow imager and dynasonde/imaging Doppler interferometer (IDI) radar wind measurements at Halley Station, Antarctica (75.6S, 26.6W) have been used to estimate the seasonal variation of the vertical fluxes of horizontal momentum carried by highfrequency atmospheric gravity waves. The cross-correlation coefficients between the vertical and horizontal wind perturbations were calculated from sodium (Na) airglow imager data collected during the austral winter seasons of 2000 and 2001. These were combined with wind velocity variances from coincident radar measurements to estimate the daily averaged upper limit of the vertical flux of horizontal momentum due to gravity waves. The resulting momentum flux at the …


The Use Of Aster Visible And Near-Infrared Reflectance Values To Estimate Aboveground Biomass In Terre Haute, In, Joel M. Overpeck Dec 2004

The Use Of Aster Visible And Near-Infrared Reflectance Values To Estimate Aboveground Biomass In Terre Haute, In, Joel M. Overpeck

All-Inclusive List of Electronic Theses and Dissertations

Researchers have established that a relationship exists between biomass and satellite reflectance values (Franklin, 1986; Anderson, 1993). Such studies focus on areas with high vegetative homogeneity, with little research being conducted in urban areas. The purpose of this study was to attain a relationship between aboveground biomass and reflectance values from ASTER's (Advanced Spacebome Thermal Emission and Reflection Radiometer) Visible and Near Infrared (VNIR) sensor. In addition a normalized difference vegetation index (NDVI) was generated from the near infrared and red bands to test its relationship with biomass. Aboveground biomass values were calculated from fifty-one 15 x 15 meter randomly …


Discovery Of The Near-Ir Afterglow And Of The Host Of Grb 030528, A. Rau, J. Greiner, S. Klose, M. Salvato, J. M. Castro Cerón, Dieter H. Hartmann, A. Fruchter, A. Levan, N. R. Tanvir, J. Gorosabel Dec 2004

Discovery Of The Near-Ir Afterglow And Of The Host Of Grb 030528, A. Rau, J. Greiner, S. Klose, M. Salvato, J. M. Castro Cerón, Dieter H. Hartmann, A. Fruchter, A. Levan, N. R. Tanvir, J. Gorosabel

Publications

The rapid dissemination of an arcmin-sized HETE-2 localization of the long-duration X-ray flash GRB 030528 led to a ground-based multi-observatory follow-up campaign. We report the discovery of the near-IR afterglow, and also describe the detection of the underlying host galaxy in the optical and near-IR bands. The afterglow is classified as “optically dark” as it was not detected in the optical band. The K-band photometry presented here suggests that the lack of optical detection was simply the result of observational limitations (lack of rapid and deep observations plus high foreground extinction). Simple power law fits to the afterglow in the …


Primitive Ideals Of Semigroup Graded Rings, Hema Gopalakrishnan Dec 2004

Primitive Ideals Of Semigroup Graded Rings, Hema Gopalakrishnan

Mathematics Faculty Publications

Prime ideals of strong semigroup graded rings have been characterized by Bell, Stalder and Teply for some important classes of semigroups. The prime ideals correspond to certain families of ideals of the component rings called prime families. In this paper, we define the notion of a primitive family and show that primitive ideals of such rings correspond to primitive families of ideals of the component rings.


Comparison Of Sampling Methods For Flatness Evaluation Using Cmm, Ashish Singhal Dec 2004

Comparison Of Sampling Methods For Flatness Evaluation Using Cmm, Ashish Singhal

All-Inclusive List of Electronic Theses and Dissertations

Efficient part feature verification using Coordinate Measuring Machine (CMM) requires efficient sample point selection as well as accurate zone fitting. This work deals with flatness tolerance evaluation and the Least- Square (LS) technique is used to compute tolerance zone. In regard to the sampling strategy there are several methods commonly employed in Coordinate Measuring Machine inspection literature. The appropriate method is selected according to the accuracy requirement, the geometry features of the work piece, and the condition of the machine producing the work piece. This research focuses on the five sampling methods: Hammersley sequence sampling, Halton-Zaremba sequence sampling, Random sampling, …


Spatial Distribution Of Competing Ions Around Dna In Solution, Kurt Andresen, R. Das, Hye Yoon Park, H. Smith, Lisa W. Kwok, Jessica S. Lamb, E. J. Kirkland, D. Herschlag, K. D. Finkelstein, Lois Pollack Dec 2004

Spatial Distribution Of Competing Ions Around Dna In Solution, Kurt Andresen, R. Das, Hye Yoon Park, H. Smith, Lisa W. Kwok, Jessica S. Lamb, E. J. Kirkland, D. Herschlag, K. D. Finkelstein, Lois Pollack

Physics and Astronomy Faculty Publications

The competition of monovalent and divalent cations for proximity to negatively charged DNA is of biological importance and can provide strong constraints for theoretical treatments of polyelectrolytes. Resonant x-ray scattering experiments have allowed us to monitor the number and distribution of each cation in a mixed ion cloud around DNA. These measurements provide experimental evidence to support a general theoretical prediction: the normalized distribution of each ion around polyelectrolytes remains constant when ions are mixed at different ratios. In addition, the amplitudes of the scattering signals throughout the competition provide a measurement of the surface concentration parameter that predicts the …


Laboratory Experiments Of Entrainment In Dry Convective Boundary Layers, Harm J.J. Jonker, Thijs Heus, Esther Hagen, Han Van Dop Dec 2004

Laboratory Experiments Of Entrainment In Dry Convective Boundary Layers, Harm J.J. Jonker, Thijs Heus, Esther Hagen, Han Van Dop

Physics Faculty Publications

Entrainment in dry convective boundary layers was studied. A saline convection tank set-up was used as a laboratory model for a dry convective atmospheric boundary layer. The entrainment flux was measured using planar laser induced fluorescence (PLIF). It was found that the entrainment flux reveals a much stronger dependence on the inversion strength than large eddy simulations tend to do.


The Glacial Geology Of Southern St. Joseph County, Michigan, Linda Nicks Dec 2004

The Glacial Geology Of Southern St. Joseph County, Michigan, Linda Nicks

Dissertations

The objective of the dissertation was to map the glacial geology in southern St. Joseph County, Michigan. The surficial geology was divided into three distinct land systems which are moraine, outwash and fan deposits. The Sturgis Moraine is the most prominent feature transecting the study area from east to west. The topography is further dissected by southwest-trending channels interpreted as tunnel channels.

Thick accumulations of sand and gravel in the study area indicate that glacial meltwater deposition played a dominant role in shaping the landscape. Based on the relative size of the channels and outwash deposits, the largest contribution from …


Origin Of The Central Kalamazoo River Valley, Southwestern Michigan, Usa, Andrew Kozlowski Dec 2004

Origin Of The Central Kalamazoo River Valley, Southwestern Michigan, Usa, Andrew Kozlowski

Dissertations

Chapter I

Introduction

Southern Michigan's geomorphology is a testament to the glacial processes that buried and sculpted the landscape during the last glaciation. Many glacial landforms in southwestern Michigan, including the Kalamazoo River Valley, provide evidence that aids in understanding the chronology, ice dynamics and glacial processes that occurred in Michigan during the last ice age.

As the climate began to warm about 20,000 yr B.P. (Larson and Schaetzl, 2001) the extensive Laurentide Ice Sheet began to recede from its maximum southern position reached during the Late Wisconsinan (Figure 1). It was at this point that modem surficial drainage systems …