Geology Exam 1
When did the Big Bang occur?
14 billion years ago.
What is a singularity?
Everything exploding from a central point.
How fast did the laws of physics and generation of matter take place?
With in the first second all the laws of physics were created and 98% of matter was created.
What did Penzias and Wilson discover?
They heard a background noise in a satellite that turned out to be radiation from Big Bang.
What is a supernovae?
Massive explosion of a star and it is thought that that is how our solar system was created.
What did Fred Hoyle do?
He discovered the significance of supernovas. Stating that there is enough energy for nuclear fusion to occur which might explain why there is thicker and heavier stuff than just Hydrogen and Helium.
What is Nuclear fusion?
Nuclear fusion is the fusing of two atoms to create something different. 2 heliums creates berilium, berilium and helium create carbon
What is a solar nebula?
A giant spinning disc of material that spins faster and flattens out and then the middle of it ignites and a sun is born.
What are Chondrites?
Samples from the sun that have landed on earth.
What does temperature sorting refer to?
Elements with higher melting points condense near the sun and lighter elements condense further away.
What are Planetismals?
The small clusters of material that combine under gravity and form these small planetismals.
What is planet differentiation?
Tempearture sorting of different materials inside the planet. Heavier elements sink to the bottom (core) and heavier elements rise to the top (crust)
How long was the precambrian?
from 4.6 billion years ago to 542 million years ago
How was our moon created?
The moon was created by a mars sized planet colliding with earth and the debris clumped together to form our moon.
What are marshmallow tectonics?
This refers to plate tectonics from the Archean. Everything was so hot that subduction did not occur so the "crusts" were colliding and piling on top of one another.
What does the formation of Gneiss on land tell us?
That there was oceanic crust forming on continental crust and then metamorphing into this. Which kind of proves marshmallow tectonics.
What significance does the Acasta Gneiss have?
It was the oldest rock discovered in the world, 4 billion years old.
What are Zircon Crystals?
They are the oldest material on earth dating back to 4.4 billion years ago
What do pillow lavas from the archean tell us?
That there was water on earth for a very long time.
What does the Great Dyke of Zimbabwe tell us?
It tells us that the earth was cool enough for igneous rock to exploit this dyke so it is the dividing line between marshmallow tectonics and current plate tectonics. 2.5 billion years
What is Laurentia?
Modern day North America.
What is the Greenville Orogeny?
The mountain chain that was formed from the first collision of the plates during the precambrian.
What is the Llano uplift?
The evidence of the Grenville Orogeny in North America.
What is Rodinia?
The first super continent formed 1.3 to 1.0 billion years ago.
What is panotia?
The second supercontinent formed 650 million years ago.
What is outgassing?
Release of gas from volcanic activity. This is how earth gained its 2nd of three atmospheres. Also formed water.
Where did the earth get the water for it oceans?
It got some from outgassing and almost half from icy comets hitting the earth.
What do the banded iron formations signify?
Iron used to be dissolved in water but when oxygen came into the atmosphere it started oxidizing and precipitating all over the globe forming these banded iron formations
When did the first snowball event occur?
2.2 billion years ago.
When did the second snowball event occur?
600 million years ago.
Why did the first snowball event occur?
The earths methane was displaced when cyanobacteria converted sunlight into oxygen causing the planet to cool rapidly and freeze.
In general, were the snowball events good for life?
Yes, every time after a snowball event occurred there was an evolutionary surge.
Why did the snowball events end?
Carbon dioxide was released through volcanic activity that and it would warm the planet back up.
What are Prokaryotic bacteria?
The first single celled organisms on earth. They are vital to life as many cycles depend on them to be carried out, such as nitrogen and carbon dioxide.
What are Prokaryotic Archea?
Second form of single celled life on earth.
What are the eukaryotes?
The first form of life that had nucleus and other organs.
What importance does Warrawoona play?
They are rocks in Austrailia that contain the oldest life on earth 3.5 billion years old
What is the Gunflint Chert?
It was the first finding of precambrian fossils which dated between 1.9 - 2.3 billion years old.
Why is it that we are carbon based lifeforms?
Carbon is the 15th most common element and it bonds easily to other elements to form new molecules such as proteins and DNA.
What did Miller and Urey do?
They did an experiment attempting to recreate the conditions of early earth where life began, they ended up making amino acids but nothing actually living.
What is the significance Murchison Meteroite?
It was a meteorite that contained 55 amino acids on it. On earth there are only 22 naturally occurring ones. It was also 4.4 billion years old.
How did the cell membrane evolve?
The cell membrane contains hydropholic and hydrophobic ends and it forms into a sphere to protect the hydrophobic ends. Sometimes it would trap some of the genetic material inside.
What are Cyanobacteria?
Where are the oldest found?
Cyanobacteria were the first cells that photosynthesized sunlight into oxygen.
The oldest ones are 2.7 billion years old found in austrailia.
What is the significance of stromatolites?
They were the first communities of organisms. There are mounds of slimy layers of cyanobacteria alternating with sand. in the intertidal zones.
How and why were Eukaryotes formed?
Eukaryotes formed by an anaerobic bacteria engulfing an aerobic bacteria. The oxygen was deadly to the anaerobic bacteria so it adapted by feeding off of the aerobic bacterias excretions.
Why was sexual reproduction introduced?
Sexual reproduction was to mix up everything. Make the cells more complex.
What was the evidence of multicellular organisms?
First proof came from a sponge that was found that was 635 million years old. Sponges are the simplest for of multicellular organisms
Who is Reginald Sprigg?
He discovered the Ediacaran Fauna while in austrailia. This fauna was from the precambrian era.
What was the significance of the Ediacaran Fauna?
They were all soft boddied organisms and there were a massive amount of them and they evolved very quickly and flourished. They dated back to 580 million years ago
What proof is there of predation?
The Ediacaran fauna suddenly vanished and soon became extinct with no sign of a global catastrophe. So the only logical thing that could have happened was that predators evolved.
What is the small shelly fauna?
The small shelly fauna evolved from the ediacaran fauna since they were soft bodied animals and had no way to protect themselves.
Geology Exam 1