Title: How do weirdly-shaped dunes inform us about the landscapes of the past, present, and future?
Speaker: Ms. Julia Cisneros
PhD candidate, UIUC; To be postdoctoral Fellow at Rice Univ./TAMU/UT Austin, starting December 2020.
Abstract: Formed through the transport of sediment through a shearing flow, bedforms record the conditions of their formation and give us clues about the movement of wind and water across an ancient landscape. In turn, bedforms also influence how sediment is transported. By influencing flow dynamics, bedforms create hydraulic roughness and heterogeneity. This talk will focus on the morphology and dynamics of dunes in alluvial channels, which make up the building blocks of alluvial channels and generate a flow field that aids in modulating the near bed shear stress by creating form roughness. Through creating variations in near bed shear stresses, dunes migrate downstream and are the major contributors to sediment transport via bedload transport. In turn, sediment transport and flow modify the dune shape in natural rivers. Understanding the links between flow, sediment transport, and bedform morphodynamics is key to leveraging these records of ancient environments, using modern bedforms to understand conditions of Earth and planetary systems, and improving how contemporary environments are managed.
This talk will highlight research that aims to investigate dune formation and dune shape in big and small rivers and under varying flow conditions. By utilizing robust bedform analysis techniques and a range of high spatial and temporal data, this talk will illuminate a new view of dune morphology in some of the world’s biggest rivers and investigate how dunes change in response to fast-changing flows, like floods. This information is vital to improving our approach to managing contemporary rivers under modern stressors and revealing the deposits of ancient rivers. In addition, this talk will highlight the story of a Tejana (a Texan Latina) geoscientist in her journey from learning about career paths in the Geosciences towards becoming a career geoscientist. This journey is grounded in her dedication towards increasing diversity, equity and inclusion in the geosciences and it is her goal to further diversify geoscience fields through the recruitment and retention of underrepresented groups. The points highlighted will include the creation of a Geoscience camp and her leadership council role in the GeoLatinas professional group.
Yorumlar