Geology Reference
In-Depth Information
Fig. 7.3
Major physiographic and morphologic features of
tide-dominated delta systems shown in (
a
) cross-section and
(
b
) planform. Note the well developed subaerial and subaque-
ous portions of the delta, each represented by a prograding
clinoform. The rivermouth is also characterized by channel-
mouth bars that build just seaward of the shoreline, and in many
cases become emergent and amalgamate into large channel-
mouth islands (Modifi ed from Hori and Saito
2007
)
7.3
Hydrodynamics
episodic) and location (e.g. active rivermouth, 'inactive'
delta plain, subaqueous delta). By defi nition, tides are
perhaps the overarching control on tide-dominated
delta systems, but the fact that these are prograding
deltas and not transgressing tidal estuaries also
refl ects the tremendous infl uence of large fl uvial
systems feeding them. In addition, large riverine
Tide-dominated deltas have complex hydrodynamics
that are strongly infl uenced by river discharge, tidal
exchange, and other marine processes such as waves
and storms (Fig.
7.3
). Each of these controls varies
considerably with time (e.g., fortnightly, seasonal,
