Michael Ramsey PhD

Laboratory Infrared Spectroscopy:
High-precision thermal infrared (TIR) vibrational spectroscopy provides information on the atomic structure of the minerals that form geologic materials. This facet of my research is focused on the spectral response that results as samples are physically mixed, varied in particle size, or heated to the point of a phase change. Measurements of entrained fine-grained ash and high-temperature melts have not been previously attempted, but results are leading to fundamental information about the structural and chemical changes that occur in volcanic materials.

Lava Flow Emplacement Dynamics:
Fundamental to understanding the behavior of lava flow and dome emplacement is the ability to extract key physical parameters about their surfaces such as temperature, vesicularity and morphology. This is being accomplished by way of near-field observations using thermal cameras, field-based multispectral TIR data, and differential global positioning system (dGPS) data collection. The formation of glassy rinds, vesicular textures, and phenocrysts are each measurable using these tools. These data provide constraints for the modeling of properties such as flow inflation, viscosity changes, and flow propagation.

Remote Sensing of Volcanic Eruptions and Processes:
Using orbital or airborne remote sensing provides the synoptic data of an active eruption and allows integration of the laboratory and field-based studies into a complete picture. My research using the ASTER sensor has resulted in a long-term funded project to develop a sensor-web approach to monitor the globe’s most active volcanoes. Of specific interest is the linkage between the renewal of activity at a volcano, the ability of remote sensing to detect that activity, and most importantly, to monitor subsequent hazards.

Planetary Surface Volcanology/Geomorphology:
My planetary research has focused on various volcanic and impact crater studies on Mars and the moon (as well as terrestrial analog sites). Thermal inertia data is being used to develop a model of interpreting eolian mantling on some of the youngest lava flows on Mars. Results should allow us to separate the spectral effects of mantling and better analyze the underlying flow compositions. Small-scale (< 2km) impact craters on Mars and the moon represent some of the most recent processes on the surface. Distinguishing impact craters from similarly-sized volcanic craters (maars) is not straightforward, but could lead to the identification of water-rich regions of the subsurface. By examining terrestrial analogs and developing new remote sensing techniques, models can be tested both of these processes.

Eolian Processes and Desertification:
Ongoing research is being conducted into eolian processes, including sediment transport, the radiative effects of dust, desertification and detection of soil moisture in a changing climate. Using remote sensing techniques to study dynamic features such as dunes provides the synoptic ability to examine changes in sediment supply and climate conditions over time. It also allows for the monitoring of marginal drought and fire prone regions susceptible to future desertification and the point-sources for larger atmospheric dust storms. New work is focused on using thermal inertia to detect soil moisture at smaller scales during periods of drought.

Urban Environmental Science and Hazards:
A long-term research interest involves the application of remote sensing and geographical information system (GIS) modeling to monitor and analyze urban growth, its impact on the surrounding environment, and the associated hazards. By using approaches similar to those used for the data analysis and visualization of volcanoes and eolian targets, key urban data products can be generated such as calibrated/geometrically accurate land use change, material identification, heat island maps and their changes over time.