Earth & Environmental Sciences

Faculty Research

Nancye H. Dawers - My research focuses on understanding the processes and time-scales over which brittle faults grow, interact and evolve.  This includes studying: 1) the structure of propagating fault tips, 2) the pattern of displacement accumulation on faults, 3) how fault displacements scale with fault length, and 4) the temporal evolution of faults via basin analysis and geomorphic studies.  At the moment, I have ongoing studies of fault evolution and landscape development in within the Eastern California shear zone, and in the northern Basin & Range.  I also have projects in south Louisiana looking at recently active "growth" fault systems, including the contribution of these large fault systems to coastal land loss.

George C. Flowers - I am currently working on the hydrologic history and climate of the Catahoula Basin with emphasis on the impoundment history as reflected in the distribution of old-growth cypress trees in the basin. 

Nicole M. Gasparini - I am interested in the processes shaping the Earth’s surface, over both short and long time scales.  I use numerical models, digital elevation maps, and field observation to quantify surface processes and understand landscape evolution.  The main focus of my research is fluvial processes (rivers), and I am particularly interested in the interactions among climate, tectonics, and erosion.

Karen H. Johannesson - The majority of my research efforts are focused on the study of trace element speciation in natural waters. I combine field, analytical, and experimental approaches in order to develop geochemical models that can improve our understanding of the biogeochemical processes that control trace element cycles in the near-surface environment.  I am particularly interested in the biogeochemistry of the rare earth elements (REE) and oxyanion-forming trace elements such as arsenic, selenium, chromium, and tungsten. My chemical hydrogeologic research centers on the “evolution” of groundwater compositions along groundwater flow paths, the roles that biogeochemical and microbial processes play in trace element speciation and mobility along flow paths in aquifer systems, and the impact of groundwater discharge to coastal waters.

Julie A. Martin - My current research deals with the characterization of wide-spread tephra deposits from large pre-historic eruptions using field observations in conjunction with numerical ash tracking models.

Ronald L. Parsley - Current research is focused on functional morphology and heterochronous development of Lower and basal Middle Cambrian gogiid eocrinoids (Echinodermata) from Guizhou Province, China.  Recent data collection (summer, 2008) based on solute homoiosteles from Ordovician strata of Estonia indicates that the evolution and morphology of brachioles is much more complicated than previously thought.

Gerhard Piringer -   I am studying the environmental impacts of a straw-based building material, from its production to its final disposal, using a technique called life-cycle assessment. The results of this work should help focus efforts at making production steps “greener”.  I am also working with Dr. VJ John and his group, who are with Tulane’s Department of Chemical and Biomolecular Engineering, on novel silica and carbon particles that incorporate zero-valent iron nanoparticles. These composite particles can degrade toxic soil pollutants such as trichloroethene (TCE).

Brad Rosenheim -  My research focuses on using isotope geochemistry to 1. assess variability in Earth’s climate system and 2. constrain Earth’s carbon cycles through time.  My research group employs an Elementar Isoprime Dual Inlet mass spectrometer that can measure H, C, N, O, and S isotopes as well as a novel ramped pyrolysis radiocarbon preparation device.  Our current projects involve assessing the role of the Mississippi River in the global carbon cycle using ramped pyrolysis radiocarbon dating, evaluating the growth patterns of deep sea corals in the Florida Straits to determine their use as paleoclimate proxies, improving chronology of Antarctic sediments that hold climatic keys to past glaciations and deglaciations, and assessing the role of the subtropical Atlantic in climate variability on the recent time scale.  The breadth of these projects reflects the research possibilities in Earth sciences employing isotope geochemistry. 

Kyle M. Straub - My research focuses on the transport of sediment from land through the ocean and into the stratigraphic record. Scales of interest range from the interaction of turbidity currents with channel bends over minutes to the construction and preservation of river deltas over millions of years. The sedimentary bodies that arise from these processes act as both home to millions of people and reservoirs of natural resources. I examine the morphodynamics of these systems using a combination of remote sensing of subsurface sedimentary deposits (visualization and interpretation of seismic data), carefully designed laboratory experiments, field studies of modern and ancient sediment transport systems, and targeted numerical analysis and modeling.

Torbjörn E. Törnqvist -  My field investigations focus on the Mississippi Delta and adjacent Gulf Coast and aim, among others, to reconcile the controversy about a Middle Holocene sea-level highstand (collaborative with Mike Blum, LSU). This is a critical element with respect to the debate about (differential) crustal movements along the Gulf Coast, a subject that we study mainly by means of comparing detailed Holocene relative sea-level records from different localities.  I am also working on the sea-level record associated with the 8.2 ka cooling event that was likely caused by the final drainage of glacial Lake Agassiz..  We study the late Holocene sea-level history and focus on possible links between sea-level change and climate phenomena such as the Medieval Warm Period and the Little Ice Age.