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

amounts of chlorite and kaolinite cement. Some K feldspar and plagioclase feldspar are
present. Some of these grains are altered and a few are being dissolved to produce
secondary porosity. Quartz overgrowths are present but broken and no other quartz
cementation is observed. A large number of quartz grains are fractured (Figure 3.6).
Sample: SGRF 9C
This sample was taken from bed 9 in the measured section labeled SGRF-
Sleeping Giant Ridge; section F (Figure 3.5). This bed has been described in outcrop as
90 m of fine-grained, parallel-laminated sand that fines up to very fine-grained sand and
silt with well-developed ripples. This bed is part of a levee facies deposit that is part of
the channel-levee sequence described at this location. The sample was taken from the
parallel-laminated section of the bed, although in thin section there is no variation in
grain size or composition that can be observed.
Mineralogy
Grains are in contact with each other, but there is a great deal of pore space.
There is minor biotite, white mica, one pyrite grain, hematite and kaolinite cement. Some
K feldspar and minor plagioclase feldspar are present, some of these grains have
undergone significant alteration (Figure 3.7). A number of quartz grains are fractured to
varying degrees, however most porosity primary.
Sample: SGRF 11B
This sample was taken from bed 11 in the measured section labeled SGRF-
Sleeping Giant Ridge, section F (Figure 3.5). This measured section records a portion of
an overturned 250 m vertical succession that has been exposed by a road cut. The sample
was taken from the upper portion of a 150 cm thick bed from an area of coarse- to
medium-grained sand that was interpreted as a channel-fill deposit. This outcrop has been
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