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PROGRADATIONAL

(Regressive, Seaward -

Stepping)

RETROGRADATIONAL

(Backstepping, Transgressive,

Landward-Stepping)

AGGRADATIONAL

Thicker, less shaly upward

Sediment source moving closer (regression)

Typical of HIGHSTAND systems tract

Similar thickness, shaliness

Sediment source maintained nearby

Typical of LOWSTAND systems tract

Upward thinning, shalier

Sediment source moving away (transgression)

Typical of TRANSGRESSIVE systems tract

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Changes in these patterns can be used for sequence stratigraphic interpretation and

correlation

Flooding Surface/

Sequence Boundar

!a"i#u# Flooding

Surface

$ncise

d

%alleSequenc

e

Boundar

&ig'stand is

#issing,

proal erodedawa

Lowstand is #issing,

proal an interfluve

TST

LST

TST

TST

TST

LST/TST

LST

&ST

Idealized parasequence stacking patterns of a complete marginal marine depositional

sequence

!a"i#u# Flooding

Surface

Transgressive Surface

&ig'stand*

+rogradational

Transgressive*

Retrogradational

Lowstand*

ggradational

&ig'stand*

+rogradational

Sequence Boundar

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2

0

12

0

-

2150

m

-

2175

m

-2200

m

-

2225

m

-

2250

m

G

R

Aggradational succession

possible composite incised valley fill

Progradational to Retrogradational -

shorefacedeltaic deposits

Aggradational to retrogradational succession

valley fill! Channel fill overlain by delta lobes!

"equence#oundary!

$a%imum

&looding "urface

Cored

interval

*

An example from Southeast Asia

$a%imum

&looding "urface!

$a%imum

&looding "urface

"equence#oundary!

Lowstand-TransgressiveSystems Tract?

Lowstand-

TransgressiveSystems Tract?

Highstand

Systems Tract?

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-

2200

m

-

2225

m

-2350

m

-

2375

m

-

2250

m

-

2275

m

-

2300

m

-

2325

m

-

2400

m

2

0

12

0

2

0

12

0

G

R

G

R

!a"i#u# Flooding

Surface

!a"i#u# Flooding

Surface

!a"i#u# Flooding

Surface

Cored

interval!a"i#u# Flooding

Surface

!a"i#u# Flooding

Surface

$a%imum

&looding

"urface!

Transgressive

Systems Tract

Transgressive

Systems Tract

Highstand

Systems TractHighstand

Systems Tract

HighstandSystems Tract