Copyright by Nysha Chaderton 2009 - The University of Texas at ...

Two or more channel complexes stack vertically to form a channel complex set
The channel complex set is bound at its base by a basinward shift in facies and at its top
by a surface of abandonment. Genetically related, stacked channel complex sets form a
channel complex system (Campion, 2000; Sprague et al., 2002. Abreu et al. et al., 2003)
(Figure 2.9).
Chalky Mount
The Chalky Mount outcrop (CM) is approximately 100 m high at its highest point
and has over 400 m of continuous lateral exposure (Figure 2.10). Steep surfaces and the
friable nature of the outcrop constrained the location of the measured sections. It is at
location 1 in Figures 2.3 and 2.4.
Description
At the Chalky Mount exposure five stratigraphic sections were measured to
document the vertical stacking of stratigraphic units and the lateral relationships between
beds. The Chalky Mount section is composed of several separate depositional cycles
which stack to form an overall fining up stratigraphic succession that is overlain by
several meters of fine grained muds and silts (Figure 2.5, 2.6). The stratigraphic section
consists of over 90% coarse-grained to granule sized sands. Individual beds at this
location are predominantly S1 and S3 beds of Facies 2 and 3 that have wavy or scoured
bases (Figure 2.11) along with the ripple laminated Tc beds of Facies 4 (Figure 2.12) and
the cm scale, interbedded sand, silt and mud Tb, Td and Te f beds that comprise Facies 5
(Figure 2.13, 2.14). The coarse grained beds of Facies 2, 3 and 4 comprise the channel
axis fill (Sprague et al., 2002; Abreu et al., 2003; Schwarz and Arnott, 2007) (Figures 2.8
and 2.9). The thin bedded turbidites of Facies 5 laterally inter-finger with channel fill
associations and are interpreted as the margins or localized levees of the channels
(Deptuck, 2003; Schwarz and Arnott, 2007). Up to nine individual channel elements
made up of channel fill and margin facies associations are at this location. Channel
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