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Full-Text Articles in Geography

What Can We Learn From X‐Ray Fluorescence Core Scanning Data? A Paleomonsoon Case Study, Daniel Gebregiorgis, Liviu Giosan, Edmund Hathorne, Pallavi Anand, Katrina Nilsson-Kerr, Anna Plaß, Andreas Lückge, Steven Clemens, Martin Frank Jan 2020

What Can We Learn From X‐Ray Fluorescence Core Scanning Data? A Paleomonsoon Case Study, Daniel Gebregiorgis, Liviu Giosan, Edmund Hathorne, Pallavi Anand, Katrina Nilsson-Kerr, Anna Plaß, Andreas Lückge, Steven Clemens, Martin Frank

Geosciences Faculty Publications

X‐ray fluorescence (XRF) core scanning of marine and lake sediments has been extensively used to study changes in past environmental and climatic processes over a range of timescales. The interpretation of XRF‐derived element ratios in paleoclimatic and paleoceanographic studies primarily considers differences in the relative abundances of particular elements. Here we present new XRF core scanning data from two long sediment cores in the Andaman Sea in the northern Indian Ocean and show that sea level related processes influence terrigenous inputs based proxies such as Ti/Ca, Fe/Ca, and elemental concentrations of the transition metals (e.g., Mn). Zr/Rb ratios are mainly …


Oxygen Isotopes In Authigenic Clay Minerals: Toward Building A Reliable Salinity Proxy, Daniel Gebregiorgis, Daniel M. Deocampo, Fred Longstaffe, A. Simpson, Gail M. Ashley, Emily Beverly, Jeremy Delaney, Javier Cuadros Jan 2020

Oxygen Isotopes In Authigenic Clay Minerals: Toward Building A Reliable Salinity Proxy, Daniel Gebregiorgis, Daniel M. Deocampo, Fred Longstaffe, A. Simpson, Gail M. Ashley, Emily Beverly, Jeremy Delaney, Javier Cuadros

Geosciences Faculty Publications

Most clay minerals in sedimentary environments have traditionally been considered to be of detrital origin, but under certain conditions, authigenic clay minerals can form at low temperature through the transformation of precursor clays or as direct precipitates from lake water. Such clay minerals can hold important information about the prevailing climatic conditions during the time of deposition. We present the first quantitative reconstruction of salinity in paleolake Olduvai based on the oxygen‐isotope composition of authigenic clay minerals. We provide a framework illustrating that the isotopic signature of authigenic lacustrine clay minerals is related to the isotopic composition of paleo‐waters, and …


What Causes People To Change Their Opinion About Climate Change?, Risa Palm, Gregory B. Lewis, Bo Feng Mar 2017

What Causes People To Change Their Opinion About Climate Change?, Risa Palm, Gregory B. Lewis, Bo Feng

Geosciences Faculty Publications

After a decade of steady growth in the acceptance of the existence of climate change and its anthropogenic causes, opinions have polarized, with almost one-third of Americans, mostly Republicans, denying that the climate is changing or that human activity is responsible. What causes Americans to change their minds on this issue? Using a large panel data set, we examined the impacts of direct experience with weather anomalies, ideology, relative prioritization of environmental conservation in comparison to economic development, and motivated reasoning that adjusts individual opinion to align with others who share one’s party identification. A generalized ordered logit model confirmed …


Spatial Distribution Of Lead In Sacramento, California, Usa, Michael J. Solt, Daniel M. Deocampo, Michelle Norris Jan 2015

Spatial Distribution Of Lead In Sacramento, California, Usa, Michael J. Solt, Daniel M. Deocampo, Michelle Norris

Geosciences Faculty Publications

Chronic exposure to lead remains a health concern in many urban areas; Sacramento, California is one example, with state surveillance data showing nearly 3% of screened children reported with blood lead levels over 4.5 μg/dL in 2009. To investigate the environmental exposure, 91 soil samples were collected and analyzed by ICP-AES and ICP-MS for 14 elements. An additional 28 samples were collected from areas of focus and analyzed by hand-held X-ray fluorescence spectrometry for Pb and Zn. Analysis of the metals data revealed non-normal distributions and positive skewness, consistent with anthropogenic input. In addition, high correlation coefficients (≥0.75) of metal …


Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik May 2012

Road Dust Lead (Pb) In Two Neighborhoods Of Urban Atlanta, (Ga, Usa), Daniel Deocampo Ph.D, Phillip Jack Reed, Alexander P. Kalenuik

Geosciences Faculty Publications

Road dust continues to be a major potential reservoir of Pb in the urban environment, and an important potential component of child Pb exposure. This study presents ICP-AES analyses of metals in 72 samples of road dust (<250 μm) collected in the urban core of Atlanta, Georgia. In the Downtown area, median Pb concentrations are ~63 mg/kg Pb, with high values of 278 mg/kg. For comparison, median Pb values in a nearby residential neighborhood (also in the urban core) were ~93 mg/kg, with a high of 972 mg/kg. Geospatial variability is high, with significant variation observed over tens to hundreds of meters. Spearman Rank Correlation tests suggest that Pb and other metals (Cu, Ni, V, Zn) are associated with iron and manganese oxide phases in the residential area, as reported in other cities. However, Pb in the Downtown area is not correlated with the others, suggesting a difference in source or transport history. Given these complexities and the expected differences between road dust and soil Pb, future efforts to assess exposure risk should therefore be based on spatially distributed sampling at very high spatial resolution.


The Impact Of Local Source Sediments On Bed Texture In The Fall River, Rocky Mountain National Park, Usa, Jordan A. Clayton, Kristopher N. Eby Oct 2011

The Impact Of Local Source Sediments On Bed Texture In The Fall River, Rocky Mountain National Park, Usa, Jordan A. Clayton, Kristopher N. Eby

Geosciences Faculty Publications

The bed texture of a gravel-bed river is related to the size distribution and quantity of source sediments, the routing of sediment through the reach, and the distribution of flow velocity. A reach morphology that is consistent in depth with little lateral topographic variation will typically have a bed texture that is characterized by a fairly uniform grain size distribution. However, spatial variations in source sediments within a given watershed may impact the distribution of gravel-bed river sediments, even at the reach scale, such that two proximal reaches of the same river having the same general morphology can exhibit contrasting …


John Borchert’S “American Metropolitan Evolution”, Risa Palm Jan 2010

John Borchert’S “American Metropolitan Evolution”, Risa Palm

Geosciences Faculty Publications

The article presents comments on the article "American Metropolitan Evolution," originally published in 1967 by the urban geographer John Borchert. Details are given overviewing the thesis and research of the paper, focusing on its discussion of the organizational structure of the four "epochs" of urban development in U.S. history. Discussion is offered explaining the significance of the 1967 paper. The author also highlights the influence which the article had on his own research and of the field at large over 40 years.


Reclaiming A Sense Of Place: Geospatial Technologies And The Flat Rock Cemetery Project, Jeffrey Glover, Kathryn Jackson, Johnny Waits Jan 2010

Reclaiming A Sense Of Place: Geospatial Technologies And The Flat Rock Cemetery Project, Jeffrey Glover, Kathryn Jackson, Johnny Waits

Geosciences Faculty Publications

The Flat Rock community in southern DeKalb County, Georgia (just outside Atlanta) is one of the oldest continually-occupied African-American communities in Georgia. Although history shows that many African-American communities in the South were broken apart as former slaves migrated north in search of jobs and a more equitable life, Flat Rock remained an intact community. This was largely due to the efforts of individuals who were able to purchase land and later sell it in small parcels to fellow community members. Proximity—both to ancestors and significant places—is a cross-culturally important component to the creation of a sense of community. Placed …


Recollections Of Gilbert F. White In Colorado, Risa Palm Jan 2008

Recollections Of Gilbert F. White In Colorado, Risa Palm

Geosciences Faculty Publications

No abstract provided.


A Volumetric Assessment Of Ancient Maya Architecture: A Gis Approach To Settlement Patterns, Kathryn Sorensen, Jeffrey Glover, Scott L. Fedick Jan 2004

A Volumetric Assessment Of Ancient Maya Architecture: A Gis Approach To Settlement Patterns, Kathryn Sorensen, Jeffrey Glover, Scott L. Fedick

Geosciences Faculty Publications

This paper will discuss the general applications of GIS technology to our research in the Yalahau Region of northern Quintana Roo, Mexico. In particular we will address the use of a volumetric analysis as a means of developing an architectural comparative framework at both the intrasite and regional scales. The comparative framework is a powerful tool that allows us to investigate and visualize the distribution of social power both within the site of T'isil and across the region. The direct relationship between social power and architectural volume is predicated on the assumption that actors who utilized the largest dwellings were …


International Telephone Calls: Global And Regional Patterns, Risa Palm Jan 2002

International Telephone Calls: Global And Regional Patterns, Risa Palm

Geosciences Faculty Publications

This study examines patterns in international telephone communications, documenting a close relationship between international call volume aggregated by nation and indicators of global connectivity including volume of international trade, tourism and migration. In addition, the analysis documents the existence of a set of national “communities” of callers. The clear orientation of large portions of the world to former colonial powers (e.g., West Africa and North Africa to France), and the separation of the Muslim Middle East and the Chinese-speaking nations of East and Southeast Asia from other calling communities suggest the importance of continuing historic and cultural influences on information …


The Internet And Home Purchase, Risa Palm Jan 2002

The Internet And Home Purchase, Risa Palm

Geosciences Faculty Publications

In the pre-internet era, information was a key determinant of the geographic nature of intra- urban moves. Information was a far more limited commodity, and therefore subject to management and even manipulation. Information brokers, particularly real estate agents, could order and limit the kinds of information to which prospective buyers gained access, with the potential of strongly biasing search space. In the past few years, a vastly enriched information source on housing vacancies has become available through real estate industry-sponsored sites on the internet. This rich information source has the potential to influence spatial patterns and processes in the search …


Classics In Human Geography Revisited: Ley, D. 1974: The Black Inner City As Frontier Outpost: Images And Behavior Of A Philadelphia Neighborhood, Risa Palm Jan 1998

Classics In Human Geography Revisited: Ley, D. 1974: The Black Inner City As Frontier Outpost: Images And Behavior Of A Philadelphia Neighborhood, Risa Palm

Geosciences Faculty Publications

No abstract provided.


Urban Earthquake Hazards: The Impact Of Culture On Perceived Risk And Response In The Usa And Japan, Risa Palm Jan 1998

Urban Earthquake Hazards: The Impact Of Culture On Perceived Risk And Response In The Usa And Japan, Risa Palm

Geosciences Faculty Publications

This paper reports on a major survey of earthquake hazard response in neighbourhoods in Tokyo-Yokohama and Los Angeles, two metropolitan areas of highly industrialized nations which routinely exchange ideas in order to try to learn from the policies, practices and experiences of the other. Survey findings showed many similarities in hazard response and preferred public policy, but also important contrasts in behaviour, and significant differences in the factors associated with these behaviours. The findings suggest caution in bi-national policy-sharing unless such sharing is preceded by a careful study of local cultural contexts.


The Roepke Lecture In Economic Geography Catastrophic Earthquake Insurance: Patterns Of Adoption, Risa Palm Jan 1995

The Roepke Lecture In Economic Geography Catastrophic Earthquake Insurance: Patterns Of Adoption, Risa Palm

Geosciences Faculty Publications

In California, earthquake insurance is not mandatory and is relatively expensive. Investment in earthquake insurance is one indicator of individual/household response to hazards in the urban environment. This paper reports on a series of three surveys of California homeowners undertaken in 1989, 1990, and 1993 in Contra Costa, Santa Clara, Los Angeles, and San Bernardino counties. The surveys addressed six hypotheses: rates of insurance subscription have increased; socioeconomc and demographic characteristics distinguish the insured from the uninsured; insurance purchase is systematically related to geophysical risk at the home site; perceived risk is a predictor of insurance purchase; experience with an …


Natural Hazards In Puerto Rico, Risa Palm, Michael E. Hodgson Jan 1993

Natural Hazards In Puerto Rico, Risa Palm, Michael E. Hodgson

Geosciences Faculty Publications

Puerto Rico faces natural hazards including hurricanes, earthquakes, tsunamis, landslides, subsidence, and flooding. Although Puerto Ricans perceive themselves as highly vulnerable to these hazards, few have adopted mitigation measures except for mandatory insurance.


Earthquake Insurance: Mandated Disclosure And Homeowner Response In California, Risa Palm, Michael E. Hodgson Jan 1992

Earthquake Insurance: Mandated Disclosure And Homeowner Response In California, Risa Palm, Michael E. Hodgson

Geosciences Faculty Publications

Earthquake insurance can reduce potentially disastrous economic losses to house• holds and is therefore a prime method of mitigating against the worst economic effects of damaging earthquakes. The decision to purchase such insurance is a special case in the general study of individual response to uncertainty in the environment. An understanding of this decision process elucidates the ways in which environmental information becomes translated into behavior change. Although California legislation has mandated the disclosure of the availability of earthquake insurance to all residential property owners since 1984, less than half of California homeowners have earthquake insurance. This paper reports on …


Racial And Ethnic Influences On Real Estate Agent Practices, Risa Palm Jan 1986

Racial And Ethnic Influences On Real Estate Agent Practices, Risa Palm

Geosciences Faculty Publications

A 1982 survey of Anglo, Black, and Hispanic real estate agents in the Denver metropolitan area suggested that race and ethnicity influence the attitudes and business practices of real estate agents. Minority real estate agents tended to gain listings from minority sellers and in areas of minority concentrations. They also have closer business relationships with other agents of the same minority group. One possible indicator of their integration into the dominant community, however, is the finding that minority agents were more likely to select personal residences in non- minority neighborhoods.


Coming Home, Risa Palm Jan 1986

Coming Home, Risa Palm

Geosciences Faculty Publications

This address argues that human geographers should be eclectic in method and open to a variety of data sources but should frame our research so as to integrate micro- and macro-level observations. To do this, we must focus on the mutual effects of agency and structure. We should under­ stand the interactions between people and environment as being neither random nor law-given but rather the combination of historical circumstance of both long and short duration, confining and yet not determining human behavior. This approach has the power to return geography to its intellectual home, an openness to the world in …


Ethnic Segmentation Of Real Estate Agent Practice In The Urban Housing Market, Risa Palm Jan 1985

Ethnic Segmentation Of Real Estate Agent Practice In The Urban Housing Market, Risa Palm

Geosciences Faculty Publications

This study investigated the extent to which the real estate industry is segmented along racial or ethnic lines. A 1982 survey of Anglo, black, and Hispanic real estate agents in the Denver metropolitan area showed ethnic segmentation in the structure of real estate business practice. Sellers select real estate agents at least partially on the basis of a common ethnicity, ethnicity affects the size and location of territories in which an agent obtains listings, and an agent's network of business contacts is limited by and is shaped by the ethnicity of the agent. Ethnicity therefore adds a further distortion to …


Home Mortgage Lenders And Earthquake Hazards, Risa Palm Jan 1985

Home Mortgage Lenders And Earthquake Hazards, Risa Palm

Geosciences Faculty Publications

A survey of major home mortgage lenders and real -property appraisers in California and the Puget Sound region shows a general inattention to earthquake hazards in appraisal and lending policy. This inattention is demonstrated not only in responses to survey questions, but also in a lack of differentiation in lending decisions between properties within and outside surface-fault rupture zones. As posited by organizational theory however, important variants exist in this overall policy, almost always resulting from the efforts of individuals within large lending organizations


The Unintended Impacts Of Anti-Redlining Legislation, Risa Palm, James Corbridge Jan 1982

The Unintended Impacts Of Anti-Redlining Legislation, Risa Palm, James Corbridge

Geosciences Faculty Publications

Federal and state legislation intended to curb the practice of geographic loan discrimination or redlining may have the unintended and undesirable effect of preventing mortgage originators from using environmental characteristics as criteria in lending evaluations. Since the California fault rupture zones (special studies zones) do not contain systematic concentrations of poor, black, or elderly households, they should be targets for differential lending policies, such as mandatory earthquake insurance or structural reinforcements as conditions for mortgage loans. A clarification of the wording of the Housing Financial Discrimination Act is needed to alleviate some of the present potentially damaging effects of failing …


Public Response To Earthquake Hazard Information, Risa Palm Jan 1981

Public Response To Earthquake Hazard Information, Risa Palm

Geosciences Faculty Publications

Consumer protection legislation has been based on the assumptions that people prefer to avoid risks and that they make rational decisions given a bounded field of information. Mandated disclosure of information about environmental hazards in limited areas should therefore result in the avoidance of such areas by homebuyers or the adoption of mitigation measures subsequent to the move. The response of California homebuyers to mandated disclosure of the location of special studies zones or surface fault rupture districts was negligible, both because of the failure of the law to specify rigorous disclosure procedures and also because the law was based …


Spatial Segmentation Of The Urban Housing Market, Risa Palm Jan 1978

Spatial Segmentation Of The Urban Housing Market, Risa Palm

Geosciences Faculty Publications

Neighborhood correlates of house price changes for the San Francisco Bay area are analyzed for the metropolitan area as a whole, and also for sub­ markets defined on the basis of real estate board jurisdictions, the racial­ ethnic composition of neighborhoods, and the average house price of neighborhoods. Regression analysis reveals different patterns of correlates for the market and submarket models, and an F-test indicates that the board of realtors submarket model is superior to the other models in accounting for variance in price change. These findings suggest that sub­ market models should be used in the analysis of housing, …


Real Estate Agents And Geographical Information, Risa Palm Jan 1976

Real Estate Agents And Geographical Information, Risa Palm

Geosciences Faculty Publications

Real estate agents in Minneapolis, Minnesota, were surveyed to ascertain the nature and degree of any geographical bias in their evaluations of urban neighborhoods. Three hypotheses were confirmed: first, that realty companies cover limited portions of the housing market; second, that overall evaluations by realtors correspond to the vacancy pattern; and third, that individual real estate agents have highly localized views of which areas are appropriate for certain types of home buyers. These empirical findings have implications for the viewpoint that the metropolitan area acts as the information frame or 'whole' in which intra-urban migration can be analyzed.