Environmental Engineering Reference
In-Depth Information
The regressive surface of marine erosion (RSME)
sensu
Plint (1988)
consti-
tutes an erosional surface that generally forms by wave scouring during forced
regression in wave-dominated shallow-water settings as a consequence of
lowered wave base.
The correlative conformity (CC)
sensu
Posamentier et al. (1988)
is a marine
stratigraphic surface that marks the change in stratal stacking patterns from
highstand normal regression (HNR) to forced regression. As such, it corre-
sponds to the sea floor at the
onset
of forced regression.
Hunt and Tucker
(1992)
refer to this surface as the “basal surface of forced regression” (BSFR).
By contrast, the CC
sensu
Hunt and Tucker (1992)
is a marine stratigraphic sur-
face marking the change in stratal stacking patterns from forced regression to
lowstand normal regression and records the sea floor at the
end
of forced
regression.
The maximum regressive surface (MRS;
Helland-Hansen and Martinsen,
1996
) is a stratigraphic surface marking a change in stratal stacking pattern from
lowstand normal regression to transgression. The term “maximum regressive
surface” is recommended where emphasis is placed on the
end
of regression,
whereas the term “transgressive surface (TS)” is recommended where emphasis
is placed on the
onset
of transgression.
Transgressive surface of erosion (TSE;
Posamentier and Vail, 1988
)isa
general term referring to transgressive ravinement surfaces (
Nummedal and
Swift, 1987
). Those that form by means of wave scouring are wave ravinement
surfaces (WRSs;
Swift, 1975
). Those formed by tidal scouring are tidal ravine-
ment surfaces (TRSs;
Allen and Posamentier, 1993
). Such surfaces are gener-
ated during transgression in coastal to shallow-water environments.
The maximum flooding surface (MFS;
Galloway, 1989; Posamentier et al.,
1988; Van Wagoner et al., 1988
) marks the change in stratal stacking pattern
from transgression to highstand normal regression. The surface is also com-
monly expressed as downlap by the overlying highstand systems tract (HST).
There are four systems tracts. The falling-stage systems tract (FSST; e.g.,
Ainsworth, 1994; Catuneanu, 2006; Plint and Nummedal, 2000
) is generated
by forced regression. The fall in RSL is indicated by erosion of the subaer-
ially exposed sediment surface updip of the coastline at the end of forced
regression and by the progradation of shallow-water deposits with a down-
stepping (offlapping) stacking pattern. The SU may be onlapped by fluvial
deposits belonging to the lowstand or the transgressive systems tracts (TSTs).
The SU may also be reworked locally by a diachronous TSE overlain by a
sediment lag.
The lowstand systems tract (LST) corresponds to deposits that accumulate
after the onset of RSL rise but during normal regression, capping the FSST and
the corresponding SU lying updip. Stacking patterns exhibit forestepping,
aggrading clinoforms that thicken downdip (in the case of siliciclastic systems),
with a topset of fluvial, coastal plain and/or delta plain deposits.
The TST comprises the deposits that accumulate from the onset of transgres-
sion until maximum transgression of the coast, immediately prior to renewed
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