7.3 Coastal and Shallow-Marine Siliciclastic Systems
LOW IN ·
~
a HIGH SEA LEVEL
TRANSGRESSIONFLUX OF -,......;::---- - - - - - - - --.,...-...- REGRESSION
SEDIMENT
LOW SEA LEVEL
MECHANICAL AND
CHEMICAl DENUDATION
OF TRANSGRESSIVE SEDIMENT
HINGE:lINE
()
..../'_S.I2~M WAVE BASE
_PRESERVED
SEDIMENT
~
(1 CYCLE)
SUBSIDENCE
SEA LEVEL
HIGH LOW
b . EROSION AND REWORKING tSTORM-WAVE)
LONG AND DEEP
AND.·S/:iALLOW
t
MECHANICAL
AND CHEMICAL
DENUDATION
TRANSGR. SHALLOW(/)
(/)
w
z
:.::
ü
:r
ISEA LEVEL
HIGH LOW
(/)
(J)
w
Z
~
u
r:
ILAG
MARINE SANDS
d
PROGRADING OF
BYPASSED SED .
(SANDS, DOlOS)
LST
HST
TST
:----~ SHALLOWING
DEEPENING
CONDENSED
LAYER
CONOENSED
LAYEAS
LST
--'::::::::::::::t:;::::f,- HST
'TST
UNITS
OF TIME
ri---...---- 8
2
1
o
319
Fig. 7.15. Response of shallow-marine sediments to
irregular relative sea-Ievel (storm-wave base)
changes (ramp setting, differential subsidence, little
influx of terrigenous sediment). a Cross-section of
basin margin. b Chronostratigra\,hic section of uppermost two cyc1es; for abbrevtations see Fig. 7.3.
c Sediment thicknesses of five cyc1es shown in
b, differences in cyc1ic sequences along cross section, and landward merging erosional unconformities
(SB 1 's). d Isochrones and asymmetric "field water
depth" curves of two sedimentary cyc1es, caused by
submarine erosion and sediment byPassing. The
curves are inferred from symmetnc sinusoidal
eustatic sea-Ievel oscillations. For further explanation
see text; abbreviations see Fig. 7.3. (After Einseie
1991 and 1992, modified).