Research

Sediments and sedimentary rocks record Earth surface processes through time and can be analyzed to reconstruct ancient environments as they relate to tectonics, climate and sea-level change, oceanic conditions, and sediment-routing system dynamics.


Sedimentary Systems from Source-to-Sink

The extent to which erosional landscapes influence their linked depositional landscapes has significant implications for basic and applied Earth science. Research on geologically young (<2 Ma) sediment-routing systems in which areas of sediment production can be linked to accumulation provides qualitative insights and quantitative constraints on source-to-sink dynamics.

  • Propagation and preservation of tectonic and climatic signals in sedimentary systems: Brian Romans and co-authors published a comprehensive review paper in 2016 in Earth-Science Reviews that discusses hypotheses related to how (or if) tectonic and/or climate signals generated in erosional catchments propagate down-system to be recorded in stratigraphic archives.
  • Signals of sediment supply in the stratigraphy of an outcropping Pleistocene alluvial fan/lacustrine succession: This project investigated how temporal patterns of sediment flux are recorded in a Pleistocene alluvial-lacustrine succession in the Great Basin of the western United States. We used cosmogenic radionuclide-derived paleo-denudation rates as a proxy for source-to-sink sediment flux. Recently completed Ph.D. student Cody Mason addressed this problem as part of his dissertation, which was funded by an American Chemical Society-Doctoral New Investigator grant. A paper about this research will be submitted in 2017.
  • Climate signal propagation in large-scale source-to-sink systems with and without continental ice sheet influence: Post-doctoral fellow Cody Mason, Brian Romans, Andrea Fildani, and others as part of a Statoil USA-funded project will be building on published work on the Mississippi system by studying the Amazon system. Stay tuned for more about this project.
  • Sediment transfer across a tectonically active continental margin: The sedimentary systems that terminate in deep-sea basins of the California Continental Borderland are ideal natural laboratories for investigating source-to-sink dynamics and evolution. See the publications page for details about our previous work in Santa Monica Basin as well as ongoing collaborative research with Dr. Jacob Covault in the San Diego Trough area.

Stratigraphic Architecture of Submarine Slope Systems

Outcrops of ancient depositional systems reveal the complexity of stratigraphy at a large range of scales and is valuable for linking processes to larger-scale stacking patterns. Outcrop studies can also be used to improve characterization and prediction of analogous systems in the subsurface.

  • Stratigraphic architecture and evolution of submarine slope deposits: Multi-scale analysis of Upper Cretaceous strata in the Magallanes Basin of southern Chile provide an opportunity to examine stratigraphic evolution in a relatively deep foreland basin (up to ~1000 m paleo-water depth). This research is part of the Chile Slope Systems consortium, a collaborative effort with Steve Hubbard (University of Calgary) and Lisa Stright (Colorado State University). M.S. candidate Sebastian Kaempfe is part of this effort. See the publications page for details about specific studies.

Cenozoic Paleoceanography of the North Atlantic Ocean

Brian Romans sailed as a sedimentologist onboard the JOIDES Resolution scientific drilling vessel for Integrated Ocean Drilling Program Expedition 342 in summer 2012. This expedition recovered sediment cores from deep-sea drift (contourite) deposits offshore Newfoundland that record paleoceanographic and paleoclimatic change going back more than 60 million years.

  • Ph.D. student Drew Parent is building on the work by recently graduated M.S. student Kristin Chilton (see below) by generating a complementary terrigenous grain-size record for the Eocene-Oligocene Transition from IODP Site U1406 on the J-Anomaly Ridge, offshore Newfoundland. Drew will also participate in a new project funded by an American Chemical Society ‘New Directions’ grant awarded to Brian Romans and Kyle Strom (in Civil & Environmental Engineering) to experimentally test the ‘sortable silt’ proxy.
  • Former M.S. student Kristin Chilton (graduate 2016) analyzed terrigenous grain-size characteristics (via the ‘sortable silt’ proxy) of samples from Site U1411 across the Eocene-Oligocene Transition, one of the most significant global climate shifts of the past ~60 million years, to test hypotheses about the response of North Atlantic Ocean circulation. A paper based on Kristin’s thesis is now in the works.
  • Former M.S. student Pat Boyle (graduated 2014) investigated the history of abyssal bottom currents by mapping the distribution of contourite deposits with seismic-reflection data tied to IODP Exp 342 cores. This work was published in Marine Geology in 2017.

Tectonic Evolution of Sedimentary Basins

Sedimentary basins are repositories for the long-term accumulation of detritus on Earth. Basin development and evolution records the interaction of Earth-surface processes and the creation/destruction of mountain belts. The composition and age of detrital minerals provide clues to the nature of mountain belts that have long since eroded. We aim to integrate studies of the detrital record using tools such as zircon geochronology with characterization of the basin architecture.

  • Tectonic evolution of the Magallanes retroarc foreland basin: Previous work by Romans and external collaborators have used the detrital record and basin-filling patterns of the Magallanes Basin to better constrain the tectonic evolution of the sediment source area, the Cretaceous Patagonian Andes. See the publications page for details about specific studies. We are currently exploring new project ideas in this area. Check back for more information in the future.