Chapter 2 Sedimentary
paleogeography-3
沉积古地理学 -3
2.1 concepts and laws
概念和定律
2.2 sedimentary-facies indicators
相标志
2.3 sedimentary environments
沉积环境 (自主互动 )
2.2 Sed,facies indicators
相标志
2.2.1 biologic indicates/生物标志
2.2.2 physic indicators/物理标志
2.2.3 chemic indicators/化学标志
2.2.4 integrated indicators/综合标志
2.2.2 physic indicators
● lithology
● structures on
bedding surface
● bedding structures
● soft-sediment
deformations
Phy
sic
sed
,
str
uc
tur
es
Lithology
Color,originated and weathered
Composition,terrigenous,intra-basinal,
volcanic and mixing
Texture,grain size,sorting,roundness,
sphericity,
micromorphology,matrix
Color,originated & weathered
Originated:
Inherited,dependent on color of clastics,e.g,
quartz sandstone-white or gray white; feldspar
sandstone-reddish,
Autogenous,originated from minerals and pigments
which are formed in the course of syndeposition
and diagenesis,e,g,glauconitic sandstone-green.
Originated colors possess stable and wide
distribution in space,and parallels to original bed
boundaries.
Color,weathered
Weathered,originated from minerals and
pigments which are formed in the course of
weathering,When bivalent irons are
oxygenated to trivalent irons (Fe2+→Fe3+) in
the rocks,the green will change into the red or
brown in the rock,
weathered color often crosscuts stratifications,
distributes along joints,cranny and fault belts,
and shows spots,massive or unstable
distribution in space.
“three-good” Conglomerate (周口店,C2)
inherited
Oxidized
haloes
Originated colors,T2y,济源
Original color,
green
Volcanic ashes
hydrolyze into
chlorite
火山灰水解 成绿泥石
Tuffaceous tempestite,
D1,北塔山,新疆
“three-good” Conglomerate ( 周口店,C2)
High maturity conglomerates,Good sorting,roundness and cementation
Baltic beach,Bornholm,Danmak B
ad
so
rti
ng
an
d
mu
lti
co
mp
os
iti
on
s
gravels
Glendonites from the Permian Wandrawandian Siltstone,Warden Head,Sydney Basin
Ikaite (CaCO36H2O)
Autogenous mineral
Glendonites that form in
water with a temperature
below 2?C
Oolitic
limestone
(滇西,
Permian)
Bedding-plane structures
Ripple marks( formed by current,wave
and wind)
Erosional structures:flute,toolmarks
Exposed structures,mud-crack,
raindrop impressions (rainpits),
salt-pseudocrystal,footprints
Ripple marks
Basic terms
Trough,crest,
Stoss side-缓
Lee side-陡
Ripple marks
rhomboidal
尖头的 新月形的悬链状的
Ripple marks
As
ymm
etr
ic
rip
ple
s,
北戴河潮坪陆地
eb
bin
g d
ire
ctio
n
eb
bin
g
rip
ple
s
pa
ra
siti
c r
ipp
les
,
北戴河潮坪
seaflooding ripples?
mudcracks,present
Mudcracks,(博格达山,井井子沟组)
Desiccation cracks were caused by the contraction of mud to form downward tapering fissures
arranged in polygonal motifs,subsequently infilled by sand.
Ichniotherium cottae
(P,Germany)
Flute
s on
the
sol
es
of
san
ds
ton
e
槽模
Bedding
层理与波痕的关系?
Relationship
between
ripples and
beddings:
surface form
&
internal
(表形层系)
Basic terms of bedding
前积纹层层系 /层系组
set-boundary/层系界面
Important beddings and illustrations
Cross-bedding,tabular,wedge-,
trough-,feather-,wave-shape
crossbedding
Horizontal,parallel,massive,
graded bedding,
climb bedding
Tidal bedding,wave-crossbedding
Horizontal,parallel,
tabular,wedge-,
trough-crossbedding;
the wedge-
crossbedding formed
by wind
Essential beddings
A
Ta
bu
lar
cro
ss
-be
dd
ing
C
Tro
ug
h cro
ss
-be
dd
ing
Wedge-bedding formed by
wind,Utah,USA
楔状层理,负载构造,滨湖相砂岩上第三系,塔北Wedge-bedding formed in the shallow lake-facies sandstone,Neogene(N2),塔北
Feather crossbedding,J,羌塘
Horizontal bedding in
the lake,N2,山旺
Parallel bedding
J,羌塘
climbing beddings
Formation of graded bedding
Graded
bedding
阿勒泰,D1
Bedding generated by wave
Bedding generated by wave,Pt3,鸡冠山,北戴河
Tida
l be
ddi
ngs
Tidal beddings,P1,NSW,Australia
flaser bedding
wav
y b
ed
din
g
Soft-sediment deformations
软沉积物变形构造
Load-casts /重荷模
Convolute beddings/包卷层理
Flames structures/火焰构造
Sandy volcanoes/砂火山
Important deformational structures
and illustrations
Load-casts on the base of sandstone bed from an
interbedded sandstone/mudstone sequence,P,天山
Loadc
as
ts
convolute beddings in the lacustrine facies,N2,山旺
Loadcasts,flames
Sandy volcanoes
2.2 Sed,facies indicators
相标志
2.2.1 biologic indicates/生物标志
2.2.2 physic indicators/物理标志
2.2.3 chemic indicators/化学标志
2.2.4 integrated indicators/综合标志
2.2.3 chemical indicators
1 structures formed by crystallization,
precipitation,eye-birds,[halite]
pseudomorphs,tepee structure etc.
2 contents and ratios of elements
3 stable isotope of carbon,oxygen and
sulfur etc,
4 biomarkers
Eye-birds in dolomite,Pt2,铁岭组,周口店
Ha
lite
ps
eudom
orphs
Tepee structure
contents and ratios of elements
南方红色风化壳区燕山大学北风化壳
Riquier et al.,2006
C12:活性大,键力强,在低价态化合物中富集,
如有机物
C13:活性小,键力强弱,在高价态化合物中富集,如碳酸盐
C12,C13,
C14 碳同位素
Walliser,1996
缺氧和还原硫酸盐细菌发育,将导致海水(硫酸盐)中?S34/S32升高海平面下降,风化增强,
87Sr/86Sr升高;火山 -热液增强 87Sr/86Sr降低
Isotopes & geohistory
Biomarkers
PTB分子化石显示蓝细菌出现两次剧烈的变化,与无脊椎动物的两次灭绝一致,反映了
P-T生物危机多阶段的特点,微生物对灾变事件有重要影响,导致了生态系统的重要变化和随后的集群灭绝。
NATURE,March 24,2005,434,494-496
Lipid biomarker
生物标志化合物记录的微生物群变化
2.2 Sed,facies indicators
相标志
2.2.1 biologic indicates/生物标志
2.2.2 physic indicators/物理标志
2.2.3 chemic indicators/化学标志
2.2.4 integrated indicators/综合标志
Ver
tica
l sequence
of
the
indi
ca
tors
----
facies
model
2.
2.
4In
tegr
ate
d i
nd
icator
s
Chapter 2 Sedimentary
paleogeography-3
The end
Chapter 2 Sedimentary
paleogeography-3
沉积古地理学 -3
2.1 concepts and laws
概念和定律
2.2 sedimentary-facies indicators
相标志
2.3 sedimentary environments
沉积环境 (自主互动 )
自主互动课安排
06-05-10(三) ; 教 3-701
每班由一名同学主讲,一名同学补充( 15’PPT + 5’); ∑提问 -回答 -讨论 25’;老师点评与补充 30’.
∑80’+25’+30’=135’
010041-蔡闹:河流
011041-施秋华,三角洲
011042-学委,滨 -浅海
011043-金晓波,半深海、深海蔡闹负责收集好 4个 PPT