module 12 Flashcards
what is a sedimentary basin?
a synclinal depression in the earth’s crust containing a thick sequence of sedimentary rocks
what is a sedimentary basin?
a synclinal depression in the earth’s crust containing a thick sequence of sedimentary rocks
Name some basins in WCSB
Pacific Basin, Alberta Basin, Athabasca Basin, Precambrian Shield, Mackenzie Basins, Wiliston Basin, Intramontane Basins
The plate tectonic theory explains where to find these sedimentary basins based on their (two things)
Physiographic Position 1)continental 2)oceanic 3)transitional between these two
Type of Plate Boundary 1)divergent 2)convergent 3)transform
What are three basin types?
Intraplate basins (pre-rift) Divergent - margin basin (syn-rift) Intraplate basins (post-rift)
What are the two types of Intraplate basins (pre-rift)
And what type of tectonic plate boundary exists there?
Intracratonic Basins (interior sag basins)
Divergent tectonics
Graben structures (interior fracture basins)
–Divergent tectonics
What is the type of basin in a divergent-margin basin (syn-rift)
And what type of tectonic plate boundary exists there?
Rift basin
–Divergence tectonics
What are the two types of basins in a Intraplate basins (post-rift)
And what type of tectonic plate boundary exists there?
Divergent continental margins
Oceanic sag basins
–Divergent tectonics
What are six basin types?
Intraplate basins (pre-rift) Divergent - margin basin (syn-rift) Intraplate basins (post-rift) Convergent-margin Basins Collision and post-collision basin
What are the two types of Intraplate basins (pre-rift)
And what type of tectonic plate boundary exists there?
Intracratonic Basins (interior sag basins)
–continenal / Divergent tectonics
Graben structures (interior fracture basins)
–continenal / Divergent tectonics
What is the type of basin in a divergent-margin basin (syn-rift)
And what type of tectonic plate boundary exists there?
Rift basin
–transitional/oceanic / Divergence tectonics
What are the two types of basins in a Intraplate basins (post-rift)
And what type of tectonic plate boundary exists there?
Divergent continental margins
–transitional / divergence
Oceanic sag basins
–oceanic / Divergent tectonics
What are the five types of basins in a Convergent-margin basin?
And what type of tectonic plate boundary exists there?
Subduction zones --oceanic / convergence Forearc, interarc, intra-arc backarc basins --transitional / oceanic divergence Retoarc foreland systems --continental / flexural Proarc foreland systems --oceanic / flexural Piggyback basin --continenal / convergence
What is the one basin that is Symmetric?
Forearc basin
What is the one basin that is Symmetric?
Forearc basin
What are the three types of basins in a Collision and post-collision basin?
And what type tectonic plate boundary exists there?
Remnant Basins(paleo-trenches) --oceanic / convergence Intramontane Basins(thrust-fold belts) --continental / divergence Foreland systems (pro/retro) --Continental / flexural
What are six basin types?
Intraplate basins (pre-rift) Divergent - margin basin (syn-rift) Intraplate basins (post-rift) Convergent-margin Basins Collision and post-collision basin Transform and transcurrent-fault (strike-slip) basin
What are the three types of basins in a Collision and post-collision basin?
And what type tectonic plate boundary exists there?
Remnant Basins(paleo-trenches) --oceanic / convergence Intramontane Basins(thrust-fold belts) --continental / divergence Foreland systems (pro/retro) --Continental / flexural
What is the type of basin in a Transform - and transcurrent fault (strike-dip basin)
Pull-apart basins
– continental/oceanic / transtension
What characteristics within a sedimentary basin are of economic importance?
- Basin physiography
- Sedimentary supply
- depositional environments
- architecture of depositional system
- subsidence rate
- burial depth and burial history
- geothermal gradient
large-scale basins form over long periods of time because of what?
Cooling and heating of the lithosphere
Describe a heated lithosphere
expands and becomes less dense because of underlying mantle. Results in uplift which is followed by an erosion event.
Describe a cool lithosphere
it subsides and forms a depression which fills with sediment. Additional loading of sediments causes additional subsidence (over millions of years)
Describe a cool lithosphere
it subsides and forms a depression which fills with sediment. Additional loading of sediments causes additional subsidence (over millions of years)
How do Divergent boundary (tensional) basins form?
Form in an early stage of Continental rift basins
Examples: east african rift and baikal rift
form in later stage of the marine passive margin basins
example: gulf of mexico and north sea
what are Four ways convergent boundary basins (compressional) are formed
In foreland basins. EX: WCSB
in forearc and backarc basins. EX:japan basin
Form due to crustal loading. ex:michigan basin
form due to vertical crustal movements. EX: Cali strike-slip basin
what are Four ways convergent boundary basins (compressional) are formed
In foreland basins. EX: WCSB
in forearc and backarc basins. EX:japan basin
Form due to crustal loading. ex:michigan basin
Form due to vertical crustal movements. EX: Cali strike-slip basin
what is regional crustal subsidence?
subsidence due to local sediment loading (delivered by major river systems) on the crust which creates a slight deformation and opens accommodation space for further sediment loading.
ex: gulf of mexico and Mississippi River
what are some rift basin characterisitics
- good examples of divergent boundary basins
- bounded by normal faults
- length up to several thousand km
- almost always in divergent plate boundaries
Drift basins evolve into?
Passive margins
Continental rifting may lead to what?
an opening of an ocean with a mid-ocean ridge
what kind of deposits does a rift-fill commonly comprise of?
fluvial , lacustrine, alluvial fans
When do evaporties form in a rift valley/basin
when they are located in a hot and dry area
when they are invaded by the sea
when they are in a closed-drainage basin
what can continued rifting lead to?
formation of oceanic crust by opening of ocean basin example = red sea
When do evaporities form in a rift valley/basin
when they are located in a hot and dry area
when they are invaded by the sea
when they are in a closed-drainage basin
what can continued rifting lead to?
formation of oceanic crust by opening of ocean basin example = red sea
examples of retro-arc foreland basins
persian gulf; WCSB
examples forearc basins
great valley sequence
how do forearc basins form?
because of mechanical subsidence and are narrow / deep. sediment
backarc basin are filled with what?
lithic rock fragments and some carbonate deposition
intra-plate sag basins are formed due to what?
thermal uplift
isostatic rebound
subsidence
ex: paleozoic michigan basin
Take home point for rift basins
some but not all rifts lead to the opening of ocean basins
take home point for foreland basins
subsidence due to loading of thrust sheets
highest subsidence closest to thrust sheets
take home point for intracratonic basins
away from plate boundaries and causes of subsidence are completely understood
what are some of the petroleum-rich basins?
north sea basin nigeria (niger delta basin) lybia (sirte basin) china / mongolia (ordos basin) oman (ghaba salt basin) sudan (muglad basin) wcsb usa russia
Facts about the Niger delta basin
a passive margin basin
tertiary age and the sediment thickness reaches up to 10km
overpressure conditions exist due to the rapid rate of sedimentation
Facts about the Sirte basin
Horst and graben structures
Facts about the Ordos basin
Cratonic basin
Facts about the Ghaba Salt Basin
part of a subsiding rift basin
Facts about the Mugland Basin
The largest known rift basin in the Sudan
Facts about the Russian Federation Basin
Has all types of basins
Facts about the West Siberian Basin
Urengoyskoe, largest gas field @ 350 TCF of OGIP
Facts about the West Siberian Basin
Urengoyskoe, largest gas field @ 350 TCF of OGIP
What are the US supergiant oil fields?
East Texas oilfield
Prudhoe Bay, alaska oilfield
what are the petroleum rich basins in Canada?
WCSB
Williston Basin
Jeanne d’Arc Basin
what percentage of HC does the WCSB contain?
57%
Williston Basin Facts
Intracratonic Sedimentary Basin
Home to the Mississippi Bakken formation
Jeanne d’Arc (Rift) basin four major oil fields are what?
Hibernia, Terra Nova, White Rose, Hebron/Ben Nevis
Hibernia has how much reserves ?
~1Billion bbls
Terra Nova as how much reserves?
~370-470 million bbls
White Rose has how much reserves?
200-250 million bbls
Hebron/Ben Nevis has how much reserves?
~700million bbls
Hebron/Ben Nevis has how much reserves?
~700million bbls
Estimated production of Canadas crude oil equivalent
WCSB 94%
Eastern Canada 6%
