GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 315-13
Presentation Time: 11:40 AM

MAGNETIC SUSCEPTIBILITY OF LOESS PALEOSOL SEQUENCES AT CLYDE: A PROXY FOR PALEOCLIMATE?


MCGANN, Gabriella Elizabeth, Whitman College, Walla Walla, WA 99362, gabbymcgann@me.com

The Palouse loess is an extensive region of windblown silt that covers up to 50,000 km of southeastern Washington, and parts of Oregon and Idaho. Loess is an important sedimentary tool that can be used to unearth information about the paleoclimate of an area; by analyzing the magnetic susceptibility of loess, one can learn about how the climate of the study area impacted pedogensis. Around the world, the magnetic susceptibility of similar loess paleosol sequences has been successfully used to reconstruct past climate. However, this technique has not been tested in the Palouse area. We studied the loess paleosol sequences at the Clyde site using magnetic susceptibility, petrographic microscope, SEM, and EDS to gain a better understanding of the trends between magnetic susceptibility and presence of iron-bearing particles. After analysis, there is a positive correlation between magnetic susceptibility and presence of iron-bearing particles. Further analysis of the iron-bearing particles shows that goethite, hematite, and some magnetite comprise some of the iron-bearing particles present within the samples.
Handouts
  • GSA Presentation McGann.pptx (47.6 MB)