Geology Reference
In-Depth Information
Fig. 8.26
Examples of three facies associations from an open-
coast to open-embayment mature (
high
) salt marsh environment
with a spring tidal range of 12 m in the Bay of Fundy (From
Dashtgard and Gingras
2005
) . (
a
) Nonorientated profi le through
the salt marsh centring on a panne (
salt pan
). (
b
) Creek-normal
section illustrating sediment deposition via channel aggradation.
(
c
) Shore-normal section through a tidal-creek point bar. The
nine facies F1-F9 are described in the text. The
dashed line
in
b
and
c
indicates the level of the
upper
erosional boundary exposed
in the foreshore
marshes in the Bay of Fundy, their results have a degree
of general signifi cance and should inspire similar stud-
ies of salt marsh deposits in other climate zones and
under different dynamic conditions.
are evaluated and described with examples from a wide
range of locations. General mechanisms and deposi-
tional conditions, however, are primarily illustrated by
examples from the Danish Wadden Sea based on the
author's own experience.
The chapter opens with an overview over measure-
ments of salt marsh sedimentation through time,
including direct measurements by means of marker
horizons and salt marsh levels and indirect measure-
ments by means of different types of dating methods.
In a description of salt marsh morphodynamics, salt
marsh sedimentation is separated into three main types:
(1) sedimentation associated with channel fl ow in the
8.7
Summary
Salt marshes defi ned as 'vegetated areas located
between coastal hinterlands and daily (or permanently)
fl ooded coastal areas' are analysed with emphasis on
depositional processes and resulting products. Salt
marsh sedimentation and related dynamic conditions
