Magnetization of Sediments and the Environment - Paleomagnetism of Sedimentary Rocks: Process and Interpretation - page 112

Fig. 8.12 FMR spectra for Lake Ely sediment collected at different depths in the piston core. The amplitude of the spectra
decreases as the sediment's magnetic intensity decreases due to reduction diagenesis. Data collected by Bob Kopp.

changes in a lake and a lake's watershed. The standard
measurements of magnetic mineral concentration,
magnetic mineral grain size and magnetic mineral
type can be used creatively, supplemented by non-
magnetic observations, to reconstruct the local envi-
ronmental past.

sequences of sedimentary rocks. Typically, environ-
mental magnetic parameters measuring the concen-
tration, grain size and type of magnetic minerals are
applied to contemporary or recent lake or marine sedi-
ments, soils or paleosols. In the simplest application of
rock magnetic cyclostratigraphy, magnetic mineral
concentration variations are used to detect orbitally
driven global climate change at millennial or greater
timescales, i.e. Milankovitch cycles, in order to provide
a high-resolution chronostratigraphy to a sequence of
sedimentary rocks. Milankovitch cycles are the subtle
variations ( c. 7%) in solar radiation input to the top of
the Earth's atmosphere, i.e. insolation, at different lati-

ROCK MAGNETIC
CYCLOSTRATIGRAPHY

Rock magnetic cyclostratigraphy is a new application
of environmental magnetic parameters to ancient