QUATERNARY SOILS: characterization and dating of buried soils used to date and correlate pluvial sequences, glacial chronologies, etc.; and to provide paleoclimatic inferrences

SOIL MORPHOLOGY: HORIZONS SOIL ORDERS:
ENTISOL  no (?) soil development
INCEPTISOL moderate devel. (A1)
ARIDISOL limited development
MOLLISOL thick dark A1
SPODOSOL light A2, Fe and Al in Bir
ALFISOL forest soils A2
ULTISOLS crystalline clays low bases
OXISOLS highly weathered soils
VERTISOLS playa, cracking soils
HISTOSOLS peats

CATENAS (Morrison, 1967)
  • facies changes in soils
  • example elevational changes
    • higher elevation = more OM in A
    • higher elevation = less Cca


RATE OF SOIL FORMATION
Horizons weakly or strongly developed depending on several factors that effect rates of chemical and physical processes
CARBONATE ACCUMULATION (Gile and Hawley, 1966)
    STAGE I thin discontinuous coatings on pebbles
    STAGE II continuous coatings, calcareous loose matrix
    STAGE III cementation

FOSSIL SOILS Soils that formed in the past
Processes that led to formation no longer operation
  • RELICT SOIL: at surface, +/- modified by modern soil
    • or be remnant of former time
    • example: red, argillic B near Tucson
  • BURIED SOIL: past soil beneath modern soil
    • e.g. histosols beneath loess in U.S. Midwest
    • e.g. soils visible in arroyos
    • may be modified by current soil forming processes if shallow
    • some buried horizons may not be visible (A1)

PALEOCLIMATE
STRATIGRAPHIC CORRELATION

Soils Readings

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