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(A)
(B)
1 m
Fig. 5. (A) Surface Image taken from XES
05 when the hangingwall basin developed
a lake autogenically. (B) A sliced dip sec-
tion (location is indicated in (A)) across
the footwall and hangingwall showing
cyclic sedimentation between fluvial and
lake facies (bounded by white lines).
0.5 m
sediment over an area with variable subsidence
rates allows enough time to develop a tectonic
depression in the surface topography, causing
periodic opening of a lake (Fig. 5A). Opening and
closing of the autogenic lake cycled twice in XES
05. During the opening of the lake, the channels
flowed away from the hangingwall basin, whereas
the channels flowed into the hangingwall basin
around and across the fault during the closing
period. Cyclic alternation between foreset and flu-
vial stratification was observed in sliced deposit
sections, which developed even without time
variations in tectonic controls (i.e. no changes
in  fault slip rate or sediment supply from the
upstream source) (Fig. 5B).
These experimental results can be extrapolated
to field conditions using scour depths as a refer-
ence scale. During the 60 hour exchange period
between foreset and fluvial deposits, about 20
scour-depths (1 scour depth ≅ 2 cm) developed in
the subsidence maximum. Assuming a 5 m scour
depth in natural depositional basins and a sedi-
mentation rate of 0.001 m/yr, the record of the full
60 hour autogenic event would be equivalent to
50 to 100 m thick strata and the entire autogenic
cycle time would be approximately 10 5 years
(Kim & Paola, 2007). This unexpected modifi-
cation of scale of the internal process suggests the
possibility of very long-period, high-magnitude
autogenic variability associated with the coupling
of channel reorganisation and active tectonic
deformation.
respond actively to multiple external controls
with a wide range of time and space scales. The
complex mixture of allogenic and autogenic sig-
natures recorded in sedimentary records presents
a puzzle; whose pieces consist of the causes and
effects responsible for basin-fill history. Physical
experiments in sediment transport and sedimen-
tary basin evolution for understanding the rela-
tionship between external and internal changes
along with associated stratigraphic architecture
have advantages over numerical modelling and
field study because 1) the depositional system in
experiments naturally self-evolves and 2) precise
managing of key external controls and monitoring
of basin evolution can be achieved.
Initial efforts should focus on isolating indi-
vidual causes and examining the complex effects
associated with autogenic dynamics. Studying
the modification of time and event scales by
autogenic processes from linear external controls
(e.g. Kim & Muto, 2007; Martin et al ., 2009b)
should be continued in order to define their fun-
damental relationship under simple conditions.
High-resolution topographic measurements in
time and space should be taken for robust inves-
tigation of event size of autogenic processes.
Coupled allo-autogenic study should also be
expanded to investigating 1)  the effect of base-
level change over a wide range of rates, 2) various
tectonic styles such as passive-margin and fore-
land basin styles and 3) long-term increase and/
or decrease in sediment supply.
One of the hurdles to overcome for improving
our ability to decouple allogenic signals from the
rock record is the suppression of signals that
come from external controls in stratigraphy.
An experiment in the XES basin was performed
in 2008 with an identical tectonic geometry as
Suggestions for future work
The Earth's surface is active over all time scales
due to external perturbations and internally organ-
ised dynamics. In nature, depositional systems
 
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