302
Chapter 7 Sequences, Minor Cycles, and Event Stratigraphy
a BASE LEVEL (Bl)
Bl-RISE
_
_
SEA OR lAKE l E V E l _ . L - - - -
--r--~
f ------ ---- /-1:-::.
I LANDSURFACE
- - - _ _ _ _
~--~ (± IRREGULAR)
INTERSECTION
SEA FLOOR
INCREASE IN SEDIMENT STORAGE
CAPACITY (ACCOMMODATION SPACE)
b SEA (LAKE) lEVEL CURVE
- - -- - - - - ' ---INFLECTION . - -
I
POINT
FREQUENCY = TIME UNIT
CYClE PERIOD
TIME
- 4
C RELATIVE SEA LEVEL
AND EQUIUBRIUM POINT
\
SUB~- ---~sÜB--"f-I~~S~B2
-
- - - -
- - -
1
'. RSL2
SEÄ FlOOR
.
"'-"'SB1 ~ 1----sB2-SLF = SEA-LEVEL FALL
SUB = SUBSIDENCE
RSL = RELATIVE SEA LEVEL
d ALLOSTRATIGRAPHY
FACIES BOUNDARIES
I':I':-;-'~' ,;""':.-:--~ .. ",:,, _ ""-_
FACIE~l ' :-S' ;' !. :s.:.;:;;i:>..,.
,::..:,:.!., -",
" - . -,
! /,- -2' ''''-_~',
ISOCHRONES '<;==';;J.:::-~~~
I '_._._._._._._.-._ . .L
~- - - - ALLOMEMBER - - - ~
(SYSTEMS TRACT, FACIES TRACT)
9 SYSTEMS TRACTS ON PASSIVE MARGINS
CROSS-SECTION SHOWING SEDIMENT THICKNESSt:S
e STRATALPATTERNS
MFS
DI~
h
f SEISMIC STRATIGRAPHY
DOWNlAP
DOWNLAP SURFACE
TYPE 2 (S82)