N. Ramos |
N. Ramos | Geology 11 Principles of GeologyGeology 11 Principles of Geology Lecture Lecture Notes: Notes: Sedimentary Sedimentary EnvironmentEnvironmentss www.eas.purdue.edu/mesozoic/lab_03/Sedi_Environments.jpg
Delta
- similar morphology to an alluvial fan but deposition results from sharp
reduction in velocity as a stream enters standing water
-Topset beds
- horizontal layers of smaller
sediment size that form as the main channel of
Transitional environments
load that the river is moving along
which consists of larger
sediments that roll along the main
channel
the river shifts elsewhere and the larger particles
of the bed load are no longer deposited
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments upload.wikimedia.org/wikipedia/commons/f/fe/Delta_beds.png
Bottomset beds
- created from the
suspended sediment that settles out
of the water as the river flows into
the body of water and loses energy
• water and sediment yield of the fluvial system feeding the
delta (climate, tectonics),
Factors Affecting Delta Formation and Facies
• seasonal changes in water level and sediment yield
(climate),
• river-mouth processes (differences in river/sea water
densities, buoyancy),
• coastal configuration, mainly shelf slope and topography
(delta gradient),
•
,
,
tidal range),
• along shore winds and currents, and
Delta
- similar morphology to an alluvial fan but deposition results from sharp
reduction in velocity as a stream enters standing water
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments www.gly.uga.edu/railsback/1121DeltaTypes.jpeg
64.19.142.12/www.pnas.org/content/104/ 43/16804/F1.medium.gif
Delta lobe switchi ng
Transitional environments
www.irishviews.com/north-antrim-coast2.jpg
North Antrim coast, Ireland
Coastal processes
Coastal processes
Waves
wind waves or wind-generated waves
surface waves that occur on the free surface of oceans, seas, lakes,
,
sea waves
- directly generated and affected by the local winds,
swell w aves
- after the wind ceases to blow
development of the wave system as it moves away from the source and
amount of energy transfer depends on:
(1) wind velocity
(2) duration of t he wind
(3) distance over whi ch the wind b lows, know n as the
fetch
Waves
Wavelength, L
horizontal distance
Wave height , H
vertical distance between
wave crest and wave trough
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments flowsurfmag.com/wordpress/wp-content/uploads/2010/12/wavegraphcrop_2007523204144.jpg
between adjacent wave
crests or troughs
Wave period, T
the time between the
passing of two successive
crests
Wave shoaling
the effect by wh ich sur face waves entering shallower water
increase in wave height (~twice the amplit ude)
Coastal processes
Coastal processes
ericbeiers.com/archive/sediment/slide0047_image060.jpg 64.19.142.13/upload.wikimedia.org/wikipedia/commons/2/2d/Propagation_du_tsunami_en_profondeur_variable.gif V- wave velocity
g- gravity
d- water depth
change in direction of a wave (bending) due to a change in i ts s peed
Coastal processes
Coastal processes
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments www.cnsm.csulb.edu/departments/geology/people/bperry/geology303/_derived/geol303text.html_txt_142BluffCoveWaveRefractionM
ar05S.gif
change in direction of a wave (bending) due to a change in i ts s peed
Coastal processes
Coastal processes
www.cnsm.csulb.edu/departments/geology/people/bperry/geology303/_derived/geol30 3text.html_txt_142BluffCoveWaveRefractionMar05S.gif 102supercoastswiki.wikispaces.com/file/view/headlands_and_bays7.jpg/232666296/ headlands_and_bays7.jpg elearning.stkc.go.th/lms/html/earth_scienc e/LOcanada6/606/images/6_6_1.jpgN. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments www.geol.ucsb.edu/faculty/sylvester/UCSB_Beaches/groins2.jpg
Longshore current
an ocean current that fl ows parallel to and close to t he shore
Coastal processes
Coastal processes
www.geol.ucsb.edu/faculty/sylvester/UCSB_Beaches/groins2.jpg elearning.stkc.go.th/lms/html/earth_science/LOcanada6/ 606/images/6_6_2.jpg spinner.cofc.edu/CGOInquiry/Graphics/longshore%20drift.gifCoastal processes
Coastal processes
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments en.wikipedia.org/wiki/Rip_currents
commonly referred to by the misnomer
, is a strong channel of
water flowing seaward from near the shore, typically t hrough th e surf line
Coastal processes
Coastal processes
typi cal flow is at 0.5 m/s and can be as fast as 2.5 m/s
Tsunami
a series of water waves caused by the displ acement of a large volum e of a
body o f w ater, usually an ocean, though it can occur in large lakes
has distinc tly different characteristic s than w ind-generated waves:
(1) enormous w avelength (100 to 200 km) but
(2) extremely lo w wave height in deep water (~1 m)
(3) long wave period (10 to 30 mins)
(4) travels w ith remarkable veloci ty (100~700 km/hr)
JR-Maglev (581 km/h)
Bluebird-Proteus CN7 (644.96 km/hr)
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments en.wikipedia.org/wiki/File:JR
en.wikipedia.org/wiki/File:JR--MaglevMaglev--MLX01MLX01--2.jpg2.jpg
wwwdelivery.superstock.com/WI/223/1895/Preview Comp/SuperStock_1895-20912.jpg
Storm surge
Coastal processes
Coastal processes
www.civildefence.govt.nz/memwebsite07.nsf/Files/Photo_library_floods2007/$file/northland%20coastal%20surge.jpgStorm surge
an offshore rise of water associated with a low pressure weather
system, typically tropic al cyclones
Coastal processes
Coastal processes
caused primarily by high w inds pushi ng on the ocean's surface,
causing the water to pi le up hig her than the ordinary sea level
64.19.142.10/upload.wikimedia.org/wikipedia/commons/thumb/4/42/Storm_surge_graphic.svg/352px-Storm_surge_graphic.svg.png
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments www.civildefence.govt.nz/memwebsite07.nsf/Files/Photo_library_floods2007/$file/northland%20coastal%20surge.jpg
64.19.142.11/upload.wikimedia.org/wikipedia/commons/thumb/3/32/Surge-en.svg/800px-Surge-en.svg.png
Seiche
Swiss French: ‘to sway back and forth’
a standing wave in an enclosed or partially encl osed body of water (e.g.,
lakes, reservoirs, swimmi ng pools , bays, harbors, seas)
Shoreline processes
Shoreline processes
Tides
rise and fall of sea levels caused by t he combined effects of the
gravitational forces exerted by the Moon and the Sun and the rotation o f
the Earth
semidiurnal - two high tides and two low tides each day
diurnal - one high and one low tide each day
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments 64.19.142.13/upload.wikimedia.org/wikipedia/en/thumb/0/00/Tide_type.gif/433px-Tide_type.gif
Coastal processes
Coastal processes and landforms
and landforms
Marine deposition
- sediment transport and depositi on by wave currents
Marine erosi on
- corrosion, corrasion or abrasion, attrition, hydraulic action, and shock
pressure of breaking w aves
64.19.142.11/upload.wikimedia.org/wikipedia/commons/thumb/4/48/Accreting_coast_Image6.svg/800px- Accreting_coast_Image6.svg.png
Marine depositional features
Marine depositional features
Spit
- a type of bar or beach, in whi ch one end connects t o land and the other
end extends i nto th e sea
- develops by the process of longshore drift
Arab at spit, Ukr aine
length: 110 km
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments ljplus.ru/img4/m/e/metelik/arabat.jpg www.rower.fan.pl/2007_Stepy/EN/kerchscholkinoleninoarabatspi
thenichevsk.jpg
Marine depositional features
Marine depositional features
Tombolo
- a narrow piece of land such as a spit or bar that connects an island to
the mainland
- formed by wave refraction
Karystos, Greece
tombolo connecting St Ninian's Isle with the
Shetland Mainland, UK
upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Tombolo_ Paximadhi_Eboea.jpg/800px-Tombolo_Paximadhi_Eboea.jpg upload.wikimedia.org/wikipedia/commons/thumb/3/33/Tombolo_
- relatively narrow strip s of sand that parallel the mainland coast
- usually occur in chains, consisting of anything from a few islands to
more than a dozen
- general requirements for formation:
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments 64.19.142.12/upload.wikimedia.org/wikipedia/commons/f/f3/Baie_de_Mobile.jpg_hyuncompressed
- theories of formation:
(1) offshor e bar
(2) spit accretion
(3) subm ergence (e.g. Mississi ppi River delta)
Barrier beaches/islands/chains
- relatively narrow strip s of sand that parallel the mainland coast
- usually occur in chains, consisting of anything from a few islands to
more than a dozen
Marine depositional features
Marine depositional features
spinner.cofc.edu/CGOInquiry/Graphics/barris.jpg thewatchers.adorraeli.com/wp-content/uploads/2011/04/barrier-island.jpg
Coastal processes
Coastal processes
Marine deposition
- sediment transport and depositi on by wave currents
Marine erosi on
- corrosion, corrasion or abrasion, attrition, hydraulic action, and shock
pressure of breaking w aves
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments
64.19.142.11/upload.wikimedia.org/wikipedia/commons/thumb/4/48/Accreting_coast_Image6.svg/800px- Accreting_coast_Image6.svg.png
Sea cliff s
- vertical or near vertical rock exposures formed by w ave erosion and
weathering
Marine
Marine erosional
erosional features
features
Kalaupapa, USA (HI)
height: 1010 m
Matengai, Japan
height: 257 m
www.fodors.com/images/experiences/Molokai-Kalaupapa-cliffs.jpg Matengai_of_Kuniga_Coast_in_Oki_Island_Shimane_pref60064.19.142.12/upload.wikimedia.org/wikipedia/commons/6/64/ .jpg
Wave-cut/shore platfo rm
- a narrow, flat area often found at the base of a sea cliff or along the
shoreline of a lake, bay, or sea that was created by th e acti on of w aves
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments 64.19.142.11/upload.wikimedia.org/wikiped
ia/commons/a/a1/Wave_cut_platform.png
www.stacey.peak-media.co.uk/purbeck/Kimmeridge/800wavevcut2.jpg
Coves/bays/bights
- area of water mostly surro unded by land often formed by differential
erosion
Marine
Marine erosional
erosional features
features
McWay Cove, USA (CA)
Bay of Bengal
area: 2,172,000 km²
upload.wikimedia.org/wikipedia/commons/thumb/8/89/McWay_cov e_1.jpg/800px-McWay_cove_1.jpg
upload.wikimedia.org/wikipedia/commons/thumb/0/0e/Bay_of_ Bengal_map.png/588px-Bay_of_Bengal_map.png
Headland/promontory/cape
- a point of land, usually high and often wit h a sheer drop, that extends
out into a body of w ater
Marine
Marine erosional
erosional features
features
Koko Head, USA (HI)
Cape Engaño, Philip pines
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments upload.wikimedia.org/wikipedia/commons/thumb/0/00/Oahu_fro
m_air2.jpg/800px-Oahu_from_air2.jpg
farm4.static.flickr.com/3013/2552847162_ddddcb28f2.jpg
Headland/promontory/cape
- a point of land, usually high and often wit h a sheer drop, that extends
out into a body of w ater
Marine
Marine erosional
erosional features
features
cgz.e2bn.net/e2bn/leas/c99/schools/cgz/accounts/staff/rchambers/GeoBytes%20GCSE%20Blog%20Resources/Images/Coasts/Hea dland_Erosion.gif
Headland/promontory/cape
- a point of land, usually high and often wit h a sheer drop, that extends
out into a body of w ater
Arc h of Cabo San Lucas, Mexico
sea cave
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments upload.wikimedia.org/wikipedia/commons/c/cd/CaboSanLucasLa
ndsEnd.JPG
upload.wikimedia.org/wikipedia/en/thumb/e/e4/Seacave_fault.jp g/512px-Seacave_fault.jpg
stacks/stumps at Torre Sant'Andrea, Italy
Old Man of Hoy, Scotland
Marine
Marine erosionalerosional features: Headlandsfeatures: Headlands
skerries which are part of the Åland Islands, Finland
upload.wikimedia.org/wikipedia/commons/thumb/8/85/Torre_San
t%27Andrea.jpg/800px-Torre_Sant%27Andrea.jpg upload.wikimedia.org/wikipedia/commons/6/63/Old_man_of_hoy2.jpg
Great Barrier reef
Moorea, French Polynesia
Coral reefs
Coastal features
Coastal features
4.bp.blogspot.com/_EH8GsUqg6-U/R1OFFQJ5-SI/AAAAAAAAAKE/tyAwfy-xwPY/s1600-R/fringe+reef+2.bmpTokelau, New Zealand
N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments
www.bayactionplan.com/wordpress/wp-content/uploads/2011/02/great-barrier-reef.jpg
upload.wikimedia.org/wikipedia/commons/6/6b/At afutrim.jpg
ALLUVIAL FAN FLUVIAL LACUSTRINE DESERT (DUNES) PALUDAL
Rock Type Breccia, Conglomerate Siltstone, Quartz arenite (sandstone) Peat, coal, conglomerate, sandstone shale, limestone, or gypsum black shale, arkose, siltstone, shale or evaporites (gypsum) siltstone
Compositi on Terrigenous Terrigenous Terrigenous, carbonate, Terrigenous or Terrigenous or evaporite evaporite
Color Brown or red Brown or red Black, brown, Yellow, red, Black, gray, TERRESTRIAL SEDIMENTARY ENVIRONMENTS
Grain Size Clay to gravel Clay to gravel Clay to silt or sand Sand Clay to silt (Fining upward) (Coarsening upward)
Grain Shape Angular Rounded to --- Rounded ---angular
Sorting Poor Variable Variable Good Variable
Inorganic Cross-bedding Asymmetrical Symmetrical ripples, Cross-bedding Laminated to ripples,
Sedimentary
graded bedding cross-bedding, lamination, cross-bedding, massive graded bedding, graded bedding,
tool marks mudcracks, raindrop prints
Organic or --- Tracks, trails, Tracks, trails, burrows, Tracks, trails Root marks, Bi ogen ic bu rr ow s r ar e s tr om ato li tes b ur ro ws Sedimentary
Structures
Fossils --- Rare freshwater Freshwater shells, --- Plant fossils, shells,
shells, bones, fish, bones, rare freshwater bones, plant fragments plant fragments
Rock Type Sandstone, siltstone, Quartz arenite, coquina Siltstone, shale, limestone, Siltstone, shale, shale, coal oolitic limestone or gypsum calcilutite,
dolostone or gypsum Compositi on Terrigenous Terrigenous or carbonate Terrigenous, carbonate, Terrigenous, carbonate,
or evaporite or evaporite Color Brown, black, White to tan Dark gray to black Gray, brown, tan
gray, green, re
Grain Size Clay to sand Sand Clay to silt Clay to silt (Coarsening upward)
Grain Shape --- Rounded to angular ---
---Sorting Poor Good Poor Variable
Inor a nici Cross-beddini , Cross-beddini , Lamination rii i , i lles, Lamination mudcracksi i , , Sedimentary graded bedding symmetrical ripples cross-bedding ripples, cross-bedding Structures
Organic or Trails, burrows Tracks, trails, burrows Trails, burrows Stromatolites,
Biogenic trails, tracks,
Sedimentary burrows
Structures
Fossils Plant fragments, shells Marine shells Marine shells Marine shells
MARINE SEDIMENTARY ENVIRONMENTS
REEF CONTINENTAL SHEL F CONTINENTAL SL OPE & RISE AB YSSAL PL AIN
Rock Type Fossiliferous Sandstone, shale, siltstone, Litharenite, siltstone, and shale Shale, chert, limestone fossiliferous limestone, (or limestone) micrite, chalk,
oolitic limestone diatomite Composition Carbonate Terrigenous or carbonate Terrigenous or carbonate Terrigenous
or carbonate Color Gray to white Gray to brown Gray, green, brown Black,
white red Grain Size Variable, frameworks, Clay to sand Clay
few to no grains
GrainShape --- --- ---
---Sorting --- Poortogood Poor Good
Inorganic --- Lamination, Graded bedding, cross-bedding, Lamination Sedimentary cross-bedding lamination, flute marks, tool marks
i i i i
Organic or --- Trails, burrows Trails, burrows Trails,
Biogenic burrows
Sedimentary Structures
Fossils Corals, marine shells Marine shells Marine shells, rare plant fragments Marine shells (mostly
