378
Chapter 7 Sequences, Minor Cycles, and Event StratigraphY
a
I -- - --- Fairweather wave base (FWB) - - -
11
ij Primary.7
- - - Storm wave base -
Ki p~oduc.tlon of
ru
life position
W btOgenlc hardparts illl
' {primary concentration) M
A
filli
Wave action
~
Tempestite
Shell lag with
incipient
hardground
/iti.,
- - -
Encrustation, recoloni.sation
Proeess
c
Shellground
Burrows
b Winnowing and
reworking
Fines
Gravel
V
/
dwellers
~~~:~~:t~g;
~· ~--u.;-:'9 shells
Soft -boltom
dwellers
Sediment buildup
d
Time
Exposure
Event eone.
Abundant burrows ,
shallow and deep
Distinct
discontinuities
Composite cone,
Burrows,
shallow and deep
Hiatal eone.
Strong bio -eros ion,
abrasion, and
fragmentation
l?!E~ag cone.