fluvial and pond sediment overview · don johnson (soil geomorphology, univ. illinois), photo by...
TRANSCRIPT
Moving from Glacial to Fluvial Focus
• Different environments
and processes at play
• But, similar geologic field
methods for lithologic
descriptions and ages
• Use modern analogs
• In glaciated areas such as
MI, fluvial processes are
highly affected by previous
glacial, glaciofluvial, and
glaciolacustrine processes
• Overlap of natural climate
and vegetation as well as
human factors
Why look interpret fluvial/pond sedimentary records?
• Describe how river behavior has changed over time
• Form and process
• Sediment sources and fluxes
• Natural range of variability vs. human altered
• Floods
• Can apply forward in time
• Understanding geomorphic context for sediment-related contaminants and nutrients
• Paleohydrology – extend modern flood records
• Geoarcheology – surfaces of human occupation
Geomorphology…. “Why that’s like just eating the skin of an apple and throwing the rest away!”
Ralph E. Langenheim, Professor emeritus, Sedimentologist Geology Department, University of Illinois Champaign-Urbana 2008 photo from http://ralphlangenheimcountyboard.blogspot.com/
#1 Skill – Field experience
Don Johnson (soil geomorphology, Univ. Illinois), photo by Randy Schaetzl (Schaetzl and Anderson, 2005)
Hilt Johnson (Quaternary geology and geomorphology, Univ. Illinois), photo by Molly Holden. Jim Knox (fluvial geomorphology, paleohydrology, Univ.
Wisconsin-Madison) photo by Faith Fitzpatrick
Ardith Hansel (Quaternary geology, Illinois State Geological Survey), photo ISGS archives.
Leon Follmer (Paleopedology, Illinois State Geological Survey Emeritus), photo ISGS archives.
#2 Skill – think in 3-D
• Be able to visualize
landscape today and in the
past, into the future
• Be able to visualize glacial
processes, large floods,
different vegetation, etc.
• Recognize that buried land
surfaces may be different
than the modern land
surface.
Pleasant Valley, Upper Pecatonica basin, photo by WI DNR
#3 Skill – Have multidisciplinary background
• Quaternary geology
• Stratigraphy
• Hydraulics/fluid mechanics
• Soils
• Paleohydrology
• Paleoecology
• Sediment transport
• Sedimentology
• Geoarcheology
• Paleolimnology
#4 Skill – Have a big toolbox
• Utilize tools from range of
disciplines
• “Present is the Key to the
Past” (James Hutton). Or is the
past the key to the future?
Morning Lectures • Fluvial sedimentary environments and features
• Fluvial
• Lacustrine/pond environments
• Manmade
• Field identification
• Soils
• Reconstructing alluvial and lacustrine sedimentary environments
• Pre field characterization
• Field methods • Coring 101
• Field descriptions
• Laboratory methods
• Examples
• Overview of field trip