Christine Downs

Christine Downs
University of South Florida | USF · School of Information Science

Doctor of Philosophy

About

18
Publications
4,175
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
19
Citations
Citations since 2016
14 Research Items
17 Citations
20162017201820192020202120220123456
20162017201820192020202120220123456
20162017201820192020202120220123456
20162017201820192020202120220123456
Introduction
I'm an early-career near-surface geophysicist. I utilize electric and electromagnetic geophysical methods (ground penetrating radar (GPR), electromagnetic induction (EMI), electric resistivity (ER)) to characterize groundwater properties and processes. My research thus far has incorporated field data, numerical model data, and inversion solutions to make interpretations about critical zone/shallow subsurface phenomena.
Additional affiliations
January 2019 - present
University of South Florida
Position
  • Research Associate
January 2019 - present
University of South Florida
Position
  • PostDoc Position
Description
  • Performing geophysical surveys at historic cemeteries to 1) document/confirm known and unknown burials, 2) contribute to the archaeological data of the site, 3) develop processing workflow specifically for archaeometry work.
July 2016 - March 2018
Sandia National Laboratories
Position
  • Intern
Education
August 2012 - December 2017
University of South Florida
Field of study
  • Geology
June 2010 - July 2012
University of Vermont
Field of study
  • Geology
September 2006 - May 2010
Salem State University
Field of study
  • Geology

Publications

Publications (18)
Article
Full-text available
This study investigates hydrogeologic controls on a peculiar, poorly studied type of geographically isolated wetland in west-central Florida, USA, locally referred to as “sandhill” (or “xeric”) wetlands. Their peculiarity lies in their connectivity to a large regional aquifer, which controls their hydrology. Evidence for this connectivity was prese...
Article
Sinkhole processes can be more complicated than vertical drainage or collapse of sediments into an underlying limestone void. To better understand the relationships between surface and underlying karst structures, geodetic and geophysical methods were applied to high-resolution mapping of active sinkhole features in covered karst, west-central Flor...
Article
Sharpening ground-penetrating radar (GPR) images remains a persistent challenge. Two approaches in particular—singular value decomposition (SVD) and sparse blind deconvolution (SBD)—have been shown to effectively denoise GPR images and resolve a reflectivity model, respectively. To our knowledge, these approaches have not been used to process GPR d...
Preprint
Full-text available
This study investigates hydrogeologic controls on a peculiar, poorly studied type of geographically isolated wetland in west-central Florida, USA, locally referred to as “sandhill wetlands.” Their peculiarity lies in their connectivity to a large, regional aquifer, which controls their hydrology and influences their ecological expression. Six wetla...
Article
Full-text available
Ground-penetrating radar (GPR) and terrestrial laser scanning (TLS) surveys were conducted at a historic cemetery at Cape Canaveral Air Force Station, Florida, U.S., in order to confirm the presence of burials corresponding to grave markers and detect potential unmarked burials. Noise in the GPR data from surface features and subtle terrain differe...
Article
Are you engaged in rigorous science? If so, ask your elected representatives to fund it robustly and predictably and to oppose policies that impede scientific progress.
Research
Full-text available
Text: 3D GPR surveys in the covered karst terrain of west-central Florida, USA, reveal surprising geometries of surficial sediments. Several meters of surficial sands overlie progressively more clay-rich sediments, which in turn overlie weathered limestone. The top of a clay-rich horizon produces an exceptionally clear GPR reflector visible from de...
Article
Full-text available
Aeromagnetic surveys over the Amargosa Desert, Nevada, have revealed the presence of several magnetic anomalies that have been interpreted to be caused by buried volcanoes; many of these anomalies have been confirmed by drilling. We present data collected from a high-resolution, ground-based magnetic survey over Anomaly B, the largest of these anom...
Conference Paper
Full-text available
Located 25 kilometers east of Flagstaff, Arizona, Rattlesnake Crater is an oblong phreatomagmatic feature in the San Francisco Volcanic Field. The shallow crater is approximately 1.4 kilometers at its widest point, and surrounded by an uneven tuff ring which is overlapped by a scoria cone volcano on the southeastern side. Improved understanding of...

Questions

Questions (2)
Question
I am processing GPR data and notice that the same diffractions in a given profile coorespond to different velocities depending on whether I am using GPR-SLICE or ReflexW. In both programs, I fit a hyperbola to diffractions to determine the velocities. We are talking 0.1 m/ns difference! Any ideas why?
Question
I am conducting a series or geophysical surveys in a mangrove/wetland environment and need some solid background knowledge. Could anyone point me in the right direction? Mangrove forests/root involvement in hydrogeology processes/coastal wetland/tidal pushing, for examples.  Thank you.

Network

Cited By

Projects

Project (1)
Project
Confirm the presence of buried features beneath original grave markers. Potentially identify unmarked buried features. Integrate terrestrial lidar point cloud data with GPR data for point cloud manipulation.