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GY 402: Sedimentary Petrology
Lecture 6: Primary and Diagnostic Sedimentary
Structures
Instructor: Dr. Douglas W. Haywick
UNIVERSITY OF SOUTH ALABAMA
1. Models of traction structures
2. Sediment transport versus aggregation
3. Wave ripples
4. Erosional features
5. Surface features
6. Intrusive (dewatering & loading) structures
7. Really diagnostic structures (just a couple!)
Today’s Lecture
Models of Traction Structures
1) Small current ripples
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
30 cm
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
50 cm
Models of Traction Structures
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Models of Traction Structures
1) Small current ripples
current
Harms, J.C., Southard, J.B., Spearing, D.R. and Walker, R.G., 1975. Depositional Environments as Interpreted from Primary Sedimentary Structures and Stratigraphic Sequences. SEPM Short Course 2.
15 cm
Models of Traction Structures
1) Small current ripples (Linguoidal)
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
10 cm
Models of Traction Structures
1) Small current ripples (lunate)
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
30 cm
100 cm
Models of Traction Structures
2) Large current ripples
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
From: Harms, J.C., Southard, J.B., Spearing, D.R. and Walker, R.G., 1975. Depositional Environments as Interpreted from Primary Sedimentary Structures and Stratigraphic Sequences. SEPM Short Course 2.
50 cm
100 cm
Models of Traction Structures
Computer animation of
ripple migration
Source: USGS Coastal & Marine Geology Web page (http://walrus.wr.usgs.gov/seds/).
Large Current Ripple Aggregation/Erosion
Sorry: This image will not play in on line
videos
75 cm
30 cm
From: Harms, J.C., Southard, J.B., Spearing, D.R. and Walker, R.G., 1975. Depositional Environments as Interpreted from Primary Sedimentary Structures and Stratigraphic Sequences. SEPM Short Course 2.
Erosion removes bed form topography
Models of Traction Structures
Trough-cross stratification
migration aggr
egat
ion
current
Migration versus aggregation
Transport versus aggregation
30 cm
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Climbing Ripples
Transport versus aggregation
Transport versus aggregation
Transport versus aggregation
Climb angle
Form through the action of “orbicular flow”
Wave ripples
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Wave ripples
Wave ripples
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Cross- stratification records aggregation versus transport
Rip up clasts
Erosional structures
Rip up clasts
Scours
Erosional structures
Rip up clasts
Scours
Channels
Erosional structures
Rip up clasts
Scours
Channels
Flute marks
Surface view
Bot
h fr
om R
eine
ck, H
.-E. a
nd S
ingh
, I.B
. 198
0. D
epos
ition
al S
edim
enta
ry
Envi
ronm
ents
. Spr
inge
r-Ver
lag,
Ber
lin. 5
49p.
Erosional structures
Rip up clasts
Scours
Channels
Flute marks
Under bed view
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Erosional structures
Rip up clasts
Scours
Channels
Flute marks
Tool marks
From Lucchi, F.R.,1995. Sedimentographica. Second Edition. Columbia University Press. 255p.
Erosional structures
Rain drop imprints
Mudcracks
75 cm
http://www.bedford.k12.ny.us/flhs/science/geoscience/images/mudcrackssample.jpg
Surface features
Ancient (Triassic)
Modern
Rain drop imprints
Mudcracks
Beastie trails
40 cm
http://www.fossilmall.com/Stonerelic/trace%20fossils/DD39/DD39c.jpg
Surface features
Ancient (Silurian)
Modern
Rain drop imprints
Mudcracks
Beastie trails
Parting lineations
75 cm
http://ic.ucsc.edu/~casey/eart150/Lectures/Foliations&Lineations/PartingLinParrsbourghNS.jpg
Surface features
Ancient (Permian)
Modern
Loads
From
Luc
chi,
F.R
.,199
5. S
edim
ento
grap
hica
. Sec
ond
Editi
on. C
olum
bia
Uni
vers
ity
Pres
s. 25
5p.
Intrusive structures
Loads
Ball and pillows
From
Rei
neck
, H.-E
. and
Sin
gh, I
.B. 1
980.
Dep
ositi
onal
Sed
imen
tary
En
viro
nmen
ts. S
prin
ger-V
erla
g, B
erlin
. 549
p.
Intrusive structures
Loads
Ball and pillows
Sand dykes (dewatering)
Intrusive structures
Loads
Ball and pillows
Sand dykes
Mud volcanoes
Both from Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
20 cm
3 m
Intrusive structures
Loads
Ball and pillows
Sand dykes
Mud volcanoes
Monroes
20 cm
From Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Intrusive structures
1) Beach environments Low angle cross-stratification
Both from: Harms, J.C., Southard, J.B., Spearing, D.R. and Walker, R.G., 1975. Depositional Environments as Interpreted from Primary Sedimentary Structures and Stratigraphic Sequences. SEPM Short Course 2.
Really diagnostic sedimentary structures
2) Muddy tidal environments
flaser bedding wavy bedding lenticular bedding
All from Reineck, H.-E. and Singh, I.B. 1980. Depositional Sedimentary Environments. Springer-Verlag, Berlin. 549p.
Really diagnostic sedimentary structures
3) Sandy tidal environments
From
Rei
neck
, H.-E
. and
Sin
gh, I
.B. 1
980.
Dep
ositi
onal
Se
dim
enta
ry E
nviro
nmen
ts. S
prin
ger-V
erla
g, B
erlin
. 549
p.
Herringbone cross-
stratification
Really diagnostic sedimentary structures
4) Deep marine environments
(density currents) Turbidites
From
Luc
chi,
F.R
.,199
5. S
edim
ento
grap
hica
. Sec
ond
Editi
on.
Col
umbi
a U
nive
rsity
Pre
ss. 2
55p.
Really diagnostic sedimentary structures
Graded bedding
HCS (hummocky cross-stratification)
From: Harms, J.C., Southard, J.B., Spearing, D.R. and Walker, R.G., 1975. Depositional Environments as Interpreted from Primary Sedimentary Structures and Stratigraphic Sequences. SEPM Short Course 2.
4) Deep marine environments (density currents)
Really diagnostic sedimentary structures
GY 402: Sedimentary Petrology
Lecture 6: Sedimentary Structures
Instructor: Dr. Doug Haywick dhaywick@southalabama.edu
This is a free open access lecture, but not for commercial purposes. For personal use only.
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