3.3 Shallow Seas
129
LOW INPUT BASINS
1) MUD
MUD·DOMINA TED
SAND + MUD
f LOW ENERGY
Si. CL. OR MARL
SAND+MUD
COASTAL
UPWELLING
I",." M ARL. LIMES T.
~""" "PE'L AGIC' LIMEST .•
':::HERT
h
HIGH ENERGY
(STORMS )
STORM·DOMINA TED
OCEANIC CURRENTS
WAVE
BASE
1
SAND+MUD
LOW TO HIGH ENERGY, ~-;~~~_
QCEANIC CURRENTS _
...,.-...,.~
r< c==..>
I - - ....... ~.~ -... -: ....
"",.."",.."..,.-'
"REWORKED EROSION
.
"'CONTINENTAL
TIDAL
SF
HCS} AMAL ·
GAMA·
ST.
TION
ShT
S+ ShT,
REWORKED
Sh.LAGS
CONDENSED
EROS.SURFACE
HARDGROUND
t
SF
F.:;~~ ST .PROXIMAL
ShT
Gr,Sh,LAGS
~~~~ ST .DISTAL
n;~~~ S. REWORKED
BIOTURB.
S,::GLAUCONITE,
CHAMOSITE
EROS. SURFACE
~~~,.. PHOSPHORITE
S.SI.CI
GLAUCONITE.
'-- _ _ _ _ _ _ _ _ _ _ _ _ ..J
OCEANIC
CURRENT
CHAMOSITE. PHOSPHORITE
LEGEND
S,
Si,
CI ,
Sh,
Gr,
sr ..
ShT,
MT,
mainly sand
mainly sill
silty clay
shell accumulalions
gravel
sandy tempestiles
sheli beds in tempestites
muddy tempestites
HCS.
FS.
SF,
BLC,
SB.
SW.
MD.
hummocky cross stratification
foreshore sands
shoreface sands
barrier island·lagoon complex
(including some tidal deposits)
offs hore sand bars
sand waves
mud draping
Fig. 3.21. (Fig. 3.20, continued). f-i Facies models of
slowly prograding coastlines and associated vertical
sequenees. All basins reeeive low input of
terrigenous material, predominantly mud (f) or both
sand and mud (g,h,i), but differ in their hydraulie
regimes and biogenie production. Stable sea level, no
subsidence. Coastal upwelling may lead to the deposition of marls and limestones rieh in organie earbon
and chert (g)