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Fig. 14.13 ( a ) The tidalites section measured in detail, showing
the tidal cycles, which are evident in Fig. 14.14 . ( b ) A typical
ripple-dominated tidalite interval, exhibiting multiple mud-draped
ripples with clear and systematic lateral changes in foreset
thicknesses indicative of changes in fl ow competence. Some
reactivation surfaces can be picked out to the left of the coin
currents, which may suggest the action of opposing
internal tides.
Shanmugam ( 2003 ) proposed that many of the cri-
teria for the recognition of tidal deposits in shallow
marine settings may be applicable in deep-water,
including: (1) Heterolithic facies, (2) rhythmites of
sandstone-shale, (3) thick-thin bundles, (4) alternation
of parallel and cross-laminations, (5) climbing ripples,
(6) double mud layers (mud couplets), (7) cross-beds
with mud-drapes, (8) superposed bidirectional cross-
bedding, (9) sigmoidal cross-bedding with mud drapes,
(10) reactivation surfaces, (11) crinkled laminae, (12)
elongate mudstone clasts, (13) fl aser beds, (14) wavy
bedding, and (15) lenticular bedding. Many of these
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