Module 14 Flashcards
THE WCSB is a good example of what kind of basin and what did it result from?
Retroarc foreland basin, resulting from a convergent boundary
retroarc foreland basins are formed due to what?
mechanical subsidence of a plate and sediment loading on the over riding plate
where is the rate of subsidence greatest in a foreland basin?
adjacent to the thrust loading
what three periods are under the mesozoic era?
triassic , jurassic, cretaceous
age of the reptiles
where was the Tethys sea in relation to pangaea?
between africa and europe and between india and asia
when did pangaea begin to break up?
mesozoic
when pangaea broke up what were the northern and southern continents called?
N - Laurasia
S - Gondwana
As north america ad europe separated what were they called?
Laurentia and Baltica
how many stages did the pangaea break up occur in?
four
what happened during stage 1 of pangaea’s break up?
- rifting and separation of N America b/c of rifting and volcanism along normal faults
- Normal Faulting -> intrusion of dikes and lava
- Atlantic ocean widened through the extrusion of oceanic basalts
what happened during stage 2 of pangaea’s break up?
- rifting and separation of Africa, India and Antarctica
- Large volumes of Basalt were extruded
what happened during stage 3 of pangaea’s break up?
- South America separated from Africa
- India moving toward asia
what happened during stage 4 of pangaea’s break up?
- Continued into the Cenozoic
- Anatarctica and Australia separated 45 mya
what happened during stage 4 of pangaea’s break up?
- Continued into the Cenozoic
- Anatarctica and Australia separated 45 mya
What was the climate like during the Mesozoic ?
Warmer climate along with the atmosphere had a higher CO2 content
What was the biggest event during the Mesozoic? and what did this event change worldwide?
The break-up of Pangaea and this event changed ocean circulation patterns and climates worldwide
when were the Rocky Mountains and Atlantic Ocean born?
During the Mesozoic
When did the oil gas traps in the gulf of mexico originate?
Mesozoic
What happened to the temperatures during the break up pangaea?
The global temperatures remained stable
Where was the North American craton situated in reference to the Sea Level during the Mesozoic
Above sea level
During the Cretaceous period the Eastern Coastal Region was inundated by what?
Marine Transgression
what was the site of major evaporite accumulation during the jurassic as North america drifted from south South America
Gulf Coastal Region
When were evaporites deposited in the Gulf of Mexico ? And what minerals were they made up of?
During the Late Triassic and Jurassic
- Thick beds of Gypsum and Salt, more than 1000m
During the Mesozoic : The tectonism affecting W North America consisted of the following orogenies:
Sonoma
Nevadan
Sevier
Laramide
Why were the mesozoic orogeny’s in W. North America formed?
Due to the changing angle of subduction of the oceanic farallon plate under the continental north american plate
what caused the sonoma orogeny in the triassic period?
caused by the collision of a volcanic arc with western north america
when did the rocky mountains form?
during the Laramide orogeny
What is accretionary tectonics?
the growth of a continent by addition of exotic terranes
mesozoic mineral resources include what?
coal , petroleum, uranium, gold and copper
why is coal deposited in WCSB valued?
because of its low sulphur content
what type of beds were deposited from volcanoes in W. North America
large thin beds of ash
The volcanic ash deposited from the volcanoes in W north america was called what?
Volcanic ash and is now altered to a soft clay called Bentonite
Why is bentonite useful?
for correlation and serve as time horizons (they can be dated radiometrically)
What era was the mass extinction of dinosaurs in?
Mesozoic which is hypothesized to occur because of the impact of a large meteorite on the Yucatan Peninsula, Mexico
What era was the mass extinction of dinosaurs in?
Mesozoic which is hypothesized to occur because of the impact of a large meteorite on the Yucatan Peninsula, Mexico
what species survived the permian extinction?
Ammonite
What are ammonites?
Invertebrates
where are the primary petroleum locations of the mesozoic era
Prudhoe bay, Alaska, Eastern Canada/Hibernia, WCSB
what are the five major producing formation from the triassic?
Charlie Lake Baldonnel Halfway Doig Montney
what are the five major producing formation from the triassic?
Charlie Lake Baldonnel Halfway Doig Montney
what are pre-orogenic sequences of the lower jurassic comprised of?
platformal limestones and cherts, and wiedespread organic rich shales
what is the upper jurassic is dominated primaly by what?
non-marine sandstones and is the first undisputed orogenic foreland trough deposits
what are major producing formation in the jurassic?
rock creek
sawtooth
upper and lower shaunavon
Nordegg
what are major producing formation in the jurassic?
rock creek
sawtooth
upper and lower shaunavon
Nordegg
Where was Cenezoic tectonism concentrated?
in the Alpine-Himalayan and circum-Pacific belts
What active volcanoes are in the Circum-Pacific Orogenic Belt?
Andes in South American
Aleutians
Cascades in North America
Island of Japan and in the Phillipines
What happend to the North American Cordillera during the Cenzoic?
Experience widespread mountain building, volcanism, uplift. and deep erosion/
What did the Laramide Orogeny create?
Basin and range structures
Extensive igneous acitivity
Uplift and erosion
What is the highest mountains in the Cordillera?
Cascade Range
What is the highest mountains in the Cordillera?
Cascade Range
Basin and range province is composed of what?
crust that was stretched and thinned as the Farallon plate subducted
The Colorado plateau is what?
a vast raised flat plain with volcanic mountains rising around its sides. Erosion has carved many deep canyons and gorges in the plateau (including Grand Canyon)
What percent of the Earth’s surface was covered with glaciers in the Pleistocene?
30%
What percent of the Earth’s surface was covered with glaciers in the Pleistocene?
30%
What area did the Pleistocene continenetal glaciers cover?
Northern Hemisphere contienents
What were the effects of the Pleistocene Glaciation?
Sea level was 130m lower than tpday
Streams transported vast amounts of sediment out to sea to be deposited at the base of the slope in submarine fan.
What are proglacial lakes?
formed by meltwater that accumulates along the margin of the glaciers.
What lakes were formed due to Proglacial lakes?
Great Lakes
What were the rock resources from the Cenezoic?
Oil in sedimentary rocks (not ab)
deposits of gold
Evaporite minerals such as borax and halite
US Gulf Coast contains approximately how much recoverable oil and from what period?
21.5 billion bbls mostly from Cenezoic reservoirs
