Geoscience Reference
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Paola 2010; Jerolmack & Swenson, 2007; Kim &
Jerolmack, 2008).
Even with current advanced technology for
imaging the subsurface in high-resolution and
more than a half-century of research aimed at
developing techniques to disentangle autogenic
noise from allogenic signals in stratigraphic data,
accurate reconstruction of allogenic variations
preserved in the stratigraphic record remains
challenging. An important foundation for many
steps to overcome this challenge is actually quan-
titatively understanding the 'noise' of autogenic
processes (Jerolmack, 2011). This includes the
understanding of 1) the autogenic processes and
their stratigraphic products and 2) complicated
reactions of the autogenic processes to basinal
forcing and the effects of these interactions on
stratigraphic products. A fundamental under-
standing of autogenic processes and their strati-
graphic products that are isolated from external
controls should be achieved first and then
changes in autogenic processes due to external
controls imposed on the system should be inves-
tigated systematically. These steps will facilitate
the decoupling of stratigraphic signatures into
allogenic and autogenic components in basin
interpretations. Field studies always deal with geo-
logical data that record multiple environmental
controls and must deduce palaeo-environmental
changes from a complicated mixture. This tradi-
tional method of interpreting basin history will
be significantly improved by the quantitative
understanding of individual causes (external
basin controls) and effects (stratigraphic products
composed of autogenic and allogenic signatures)
under controlled conditions through physical
tank experiments.
This paper presents a review of the previous
experimental studies. Firstly, fluvial autogenic
processes isolated from the effect of basin forcing
(i.e. no sea-level change or tectonic activities) are
introduced. Then, a set of tank experiments that
were conducted with changes in basin forcing is
reviewed. This paper also presents two experi-
ments that both show similar cyclic sedimenta-
tion; although one is caused by autogenic fluvial
cycles under a steady tectonic forcing and the
other is caused by cyclic tectonic variations.
Finally, suggestions for potential studies using
physical and mathematical experiments, to
enhance the current results and understanding of
the autogenic processes, are discussed.
QUANTIFYING FLUVIAL AUTOGENIC
PROCESSES
Recent experimental studies with sediment and
water (Fig. 1) clearly demonstrate self-organisation
due to internally driven sediment transport pro-
cesses (e.g. Ashworth
et al
., 2004; Bryant
et al
.,
1995; Cazanacli
et al
., 2002; Heller
et al
., 2001;
Hickson
et al
., 2005; Jerolmack & Mohrig, 2005;
Kim & Jerolmack, 2008; Kim & Muto, 2007; Kim &
Paola, 2007; Kim
et al
., 2006a; Muto & Steel, 2001;
Paola, 2000; Paola
et al
., 2001; Paola
et al
., 2009)
and suggest an opportunity to investigate quanti-
tatively the morphodynamic and stratigraphic
representations of autogenic processes. The cur-
rent advancement in experimental technology
allows for better control in boundary conditions;
and therefore a simpler mixture of autogenic pro-
cesses with environmental variations for investi-
gation. This section details previous experimental
studies that focus on autogenic processes under
either no or minimal external controls (i.e. base-
level change and tectonic variation).
Fluvial autogenic sediment storage and release
Recent publications in tank experiments have
observed strong landward-to-seaward fluctuations
in shoreline position from an overall prograda-
tional experimental delta under both constant
(A)
(B)
1 m
Fig. 1.
Experimental fluvial surface taken during XES 02
showing (A) a sheet-flow dominated sediment storage
event and (B) strong channelisation with a release event.
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