110
a
C
OCEAN BASIN
EARTH
CONT INENT
LOW TIDE
NARROW SHELF
HIGH TIDES
OCEAN BASIN
d
ADJACENT SEA,
WIDE, DEEP ENTRANCE
Fig. 3.9. a Simplified view of a rotating slice of the
Earth beside a stationary Moon to explain oceanic
tides. bLandward migration of tidal wave leading to
an increase in tidal range from deep to shallow water
On the continental shelves of the present-day oceans,
tides higher than 2 to 3 m usually occur in regions
where the shelf is at least 100 to 200 km wide. The
tidal range is further enhanced, if tidal waves behind
Chapter 3 Coastal and Shallow Sea Sediments
MOON
b
HIGH liDES
WIDE SHELF
2
BA Y, FUNNEL -SHAPED
in relation to shelf width. C Increased tidal range in
funnel-shaped bay, but subdued tide in estuary.
d Tides and tidal ranges controlled by the orientation
of elongated ocean basins and adjacent basins
a shallow sea are funneled into a bay with a wide
opening (producing tidal ranges up to 10 to 15 m).
East-west extended bays, fjords, or adjacent seas
give rise to higher tides than north-south extended