Final ESS Flashcards
(34 cards)
What was Descartes contribution to Earth Science?
His book Principe Philosophiae
- Theorie that earth formed from the material fo an extinguished star
- his 4 phases of cooling: interior layers, outer layer cracked and collapsed, oceans and continents are made—
You learned about two prominent earth scientists who worked in Saxonia. Why Saxonia? Who were they, and what was one key argument each brought forward?
Werner- The Neptunist theory
Agricola- De Re Metallica in which he provides as classification and guide to all things mineral as well as noting the formation of strata(not really an argument but whatever)
Why Saxonia- It was a major mining town…?
How did Werner explain the formation of Basalt in two ways? Why could he get it wrong?
- In unit 2 of formation stages: stratified mountains-it is original sediment precipitate
- In unit 4: volcanic rocks-that which has been later altered by heating
He got it wrong because -
Basalts are very finely grained and form specular cooling cracks ( can’t see the interlocking formation and the cracks are similar to drying cracks of mud)
Runny lava from thin sheets that looks like sedimentary layers
What were observational clues for Hutton that rocks formed as magma?
Granite near Aberdeen contains quartz inside feldspar inside quartz which cannot form from an aqueous solution
Glen Tilt: veins of granite that cross-cuts rocks is traceable to a larger granite body
Differentiate between Neptunism and Catastrophism.
WHile Neptunism seems to fit the definition od Catastrophism, cata. doesn’t specify a large flood as the engine for rock formation, simply colossal events. There are no similarities in the process of creating more time frame of the creation of rocks.
How did Hutton explain the rock outcrop at Siccar Point?
He explained the unconformity as being due to the repeated cycles of deposition, uplift, and erosion.
Name 3 stratigraphic principles outlines by Steno.
Original horizontality
Superposition
Continuity
How did Cuvier (and Brongniart) use fossils?
They used fossil characteristics to correlate rocks (near Paris)
Lead to the geologic column
Classified and grouped strata
What was Smith’s contribution to paleontology and stratigraphy? Which other achievement is he famous for?
Developed the principle of faunal succession -which correlated strata tot he appearance and extinction of species
He is also known for his geological map of England based on fossil correlation
What is today’s scientifically best estimate for the age of the earth?
- 568 billion years–says my notes
4. 543 billion years–says the internet
How did Von Buch explain the formation of mountains
As a domal subsurface intrusions of magma cracking, releasing magma to surface, collapsing of the dome.
- mountains are the elevated rim
- mountain chains require linear intrusion
Which observation would de Beaumont stress to defend his hypothesis for the formation of mountains? No clue
Crust buckles and forms mountains-violent due to compressional stress…can cause extinctions…..?
Why do mountains not deflect the plumb line by as much as expected?
Why do mountains not deflect the plumb line by as much as expected?
Wegener offers 3 ideas as part of his hypothesis, what are these?
Continental blocks raft in a dense oceanic “magma”
Displacement across Atlantic happened in geologic time
Continents are still moving
What was Holmes’ suggestion in support of continental drift?
That the mantle convection could force continents towards or away from each other
He provided a new mechanism for the drift then the previous one that was easily disproved
How could the group Runcorn satisfy themselves that continents move?
By looking at the APWP observable in the igneous and sedimentary rocks …?
What is the Vine-Matthews-Morley hypothesis? Provide a sketch.
Newly created sea-floor magnetizes in the direction of the magnetic field, and as the sea-floor spreads, it records alternately magnetized patterns.
Why do oceanic mountains sink into the ocean?
Because the mountains are slowly pushed away from the MOR with time and into deeper waters…?Like with Goytes.
Draw MOR
Did u actually?
What is the difference between continental drift, sea-floor spreading, and plate tectonics?
Technically all part of the continental drift hypothesis, continental drift refers to the idea that all the continents were once one giant landmass that split and move around the globe. Sea-floor spreading, a mechanism for the continental drift hypothesis refers to the mantle convection and the mid-ocean ridge system while plate tectonics allows for both continental drift and the mid-ocean ridge system to function…?shitty answer should work on
Why has evolution happened on Earth? Is it happening now?
Evolution happens when individuals of a species are better suited for the environment and they become the new form/variation of the species.
Evolution is still happening today although our climate is changing too quickly for the evolution to keep up so its not much use.
What is mass extinction? Name at last (at least or the last…?idk) two examples of mass extinctions we find in the geological record.
When >75% of species go extinct
Ordovician-Silurian and the Late Devonian
Compare three often-cited causes for mass extinctions.
Anoxia: ex) Permian-Triassic
-Typically in Oceans -when there is no oxygen -Many geologists believe oceanic anoxic events are strongly linked to the slowing of ocean circulation, climatic warming, and elevated levels of greenhouse gases.
Meteorite impact: ex) Cretaceous-Paleogene
Volcanic eruptions: ex)Deccan traps (same age as Cretaceous-Paleogene) and Siberian Traps (same age as Permian-Triassic)
Alvarez suggested that a meteorite impact was responsible for a major mass extinction 65 Million years ago. Explain the evidence they put forward to substantiate this claim.
The clay layer high in iridium discovered in Italy (then around the world)
Also glassy spherules, shocked quartz crystals, microscopic diamonds(evidence for great temperatures and pressures)
Chicxulub crater in Mexico………evidence: gravity anomaly, tsunami deposits, submarine landslides
