Geology
Early explanation for fossils
In the 4th century BCE Aristotle made critical observations of the slow rate of geological change. He observed the composition of the land and formulated a theory where the Earth changes at a slow rate and that these changes cannot be observed during one person's lifetime. Aristotle developed one of the first evidence-based concepts connected to the geological realm regarding the rate at which the Earth physically changes. He realized that coastlines change. Sea arches collapse and turn to sea stacks. The shorelines move but it happens so slowly one man can't observe it in his lifetime.
Many people believed that fossils grew underground. They called them 'the devil's toesnails' or tongue stones.
The Rock Cycle
https://youtu.be/7Bxw4kkeHJ8
https://youtu.be/EjnsLu6RyYU
Sedimentary Rocks
A Danish Catholic bishop by the name of Nicholas Steno took up the hobby of studying rocks in between his biblical studies. He understood different types of rock and observed that they must lay sequentially. In theory the lower rock being older than the rock on top.
In the 1790s, William Smith hypothesized that if two layers of rock at widely differing locations contained similar fossils, then it was very plausible that the layers were the same age.
Thus today scientists recognize the stratigraphy of the ground to show successive age with different kinds of fossils in each layer.
P77 - 25 Rocks
Quote on page 154 - 25 rocks
Volcanoes
Biggest volcanoes in the galaxy is Olympus Mons. It's on Mars and is twice as big as Everest.
Pompeii- chapter 1 of 25 rocks
Plate tectonics
James Hutton was an early earth science enthusiast. He lived in Scotland and loved the rugged landscape surrounding him. He noticed the signs of a gradually changing coastline that Aristotle had observed 2000 years previously. Hutton visited Hadrian's wall, known to be built in the times of the Roman's. He was impressed with how little it had changed in 1,600 years. This led him to consider that erosion happens extremely gradually.
In 1785, Hutton proposed that the interior of Earth was hot and that this heat was the engine which drove the creation of new rock: land was eroded by air and water and deposited as layers in the sea; heat then consolidated the sediment into stone and uplifted it into new lands. This theory, known as "Plutonism", stood in contrast to the "Neptunist" flood-oriented theory.
Hutton loved to walk his dog misty in the mountains that surround Edinburgh. At the time he was studying stratigraphy, the layers of the earth.
"Lord pity the arse that's clagged to a head that will hunt stones," lamented a rock-hunting, saddle-sore James Hutton. Rock hunting, he had discovered, was punishing work.
Most of the west believed Noah's flood was to blame for earth's landscape. Hutton however, believed in the increasingly popular theory of uniformitarianism. This belief said that the uniform processes in nature have been consistent throughout time. Within his field of geology he sought out earth's history. Rocks held a potential key to unraveling the past. When Hutton was walking his dogs around the mountains surrounding Edinburgh he realized that the bottom of the cliffs held sedimentary stone and at the top was igneous. From his research he knew sedimentary was the result of an extended period of pressure solidifying debris. Igneous was the result of cooling molten rock. This meant that sedimentary rocks had a long time to form before lava covered it and the volcano became dormant.
https://youtu.be/lE2j10xyOgI
https://youtu.be/7CPv0NSIG2M
Earthquakes
Chapter 22 & 23 of 25 rocks
https://youtu.be/dY_3ggKg0Bc
https://youtu.be/LQwZwKS9RPs
Volcano eruptions are spectacular events, one that has been feared and amazed since humans began walking on earth. Volcanoes have long been worshipped and seen as Gods. The Roman God Vulcan was believed to control volcanoes. In the pacific the Hawaiian people and Moari people used to have volcano Gods. Some scholars believe that the God of the old testament was a volcano. Exodus 24 talks of a pillar of smoke at the top of the mountain and "devouring fire on top of the mount."
Even up until the 1800's volcanoes weren't very understood.
"The volcano was not created to scare superstitious minds and plunge them into fits of piety and devotion. It should be seen as the vent of a furnace." - James Hutton
Hutton also put forward a thesis for a ‘system of the habitable Earth’ proposed as a deistic mechanism designed to keep the world eternally suitable for humans. He pointed to Unconformities in the rock which showed sedimentary rock lateral to igneous.
https://youtu.be/KKTXxZSz-9s
https://youtu.be/7CPv0NSIG2M
https://youtu.be/y90iJNrOPSQ
https://youtu.be/JCEDCcHcpYE
Continental Drift
Wegener spent a lot of time in isolation with various maps. He noticed that Greenland looked to fit neatly between north America and northern Europe. He then noticed how Africa might fit into south America.
In 1914, Wegener was recalled to Germany to serve in WW1. He was injured twice and got transferred to the weather division. It was at this time that he first wrote The Origin of Continents and Oceans. It explained his idea that the continents were once all one land mass he named Pangea. Wegener suggested that these separated and drifted apart, likening them to "icebergs". Supporting evidence for the idea came from the matching of the rock formations along these edges. Confirmation of their previous contiguous nature also came from the fossil plants. Wegener himself had found fossils of tropical plants in the arctic.
Map of mountains
Wegener's work was initially not widely accepted. After the war he went back to doing research in Greenland. In 1930, Wegener died during an arctic expedition in which they misjudged rations and attempted to eat their sled dogs to stay alive. He never lived to see his idea widely accepted.
What if Pangea never broke apart?
Volcanoes dot to dot
Biggest earthquakes in history
Seashells on mountains
Thousands of years ago people had made discoveries of sea shells on mountains. It was long believed that these were the results of an ancient global flood. However, 500 years ago Italian polymath was the first to theorize that mountains gradually rose from the oceans.
His theory wasn't completely accurate
Paleomagnetism
Subduction
Age of the Earth
George-Louis Buffon
In 1788 France, Buffon proposed a theory of reproduction that ran counter to the prevailing theory of pre-existence. The early volumes were condemned by the Faculty of Theology at the Sorbonne. Buffon published a retraction, but he continued publishing the offending volumes without any change.
Basing his figures on the cooling rate of iron tested at his Laboratory the Petit Fontenet at Montbard, he calculated that the age of the Earth was 75,000 years. Once again, his ideas were condemned by the Sorbonne, and once again he issued a retraction to avoid further problems.
Lord Kelvin
1862, the physicist William Thomson, 1st Baron Kelvin published calculations that fixed the age of Earth at between 20 million and 400 million years. He assumed that Earth had formed as a completely molten object, and determined the amount of time it would take for the near-surface temperature gradient to decrease to its present value.
Radioactive Dating
Ernest Rutherford and Frederick Soddy jointly had continued their work on radioactive materials and concluded that radioactivity had an observable and uniform decay rate.
With a specialized microscope, scientists could observe the decay of the most unstable of atoms. They knew how fast these atoms decay and so they could calculate the age of the rock.
An equivalent would be: if we have 500ml cup of water and we know that 1ml evaporates every hour. We find 494ml, we know it's been there about 6 hours.
In 1921, based on this theory, scientists estimated earth to be billions of years old. Today scientists believe it to be 4.5 billion years old.
Radioactive elements decay. Different radioactive elements decay at different rates. However these decay rates have been observed to be consistent and uniform. This is useful because scientists can use it to date objects.
These elements all have limits
Carbon - 50,000 years
Potassium-Argon
Lead-Uranium
Some people have attempted to disprove the dating results. One common tactic is to send something millions of years old for carbon dating. What would be the problem with that?
Scientists have explored concerns about the accuracy of these methods. One effective way to confirm the accuracy is to test the half life of two elements. If two results agree you increase your chances of it being somewhat accurate.
It has been suggested that decay rates could have been different in the past. However, for the results to be in anyway problematic, all the decay rates would've had to changed at the same rate, which seems highly unlikely. For example, if the assumption of consistent uranium decay and the assumption of consistent potassium decay give similar dates then the two elements must have had altered decays at the same rates.
Also, when compared with geological stratification, radiometric dating appears to work on the same timeframes as layers being put down.
People arguing against radiometric dating aren't complaining that the earth is a million years older or younger but instead arguing that the earth is 6,000 years old opposed to 4.5 billion. That's a difference of 4 billion, 499 million 994 thousand. It's so far off it's actually off by 750,000 times. To suggest the world is actually 6,000 years old and radiometric dating is inaccurate because it assumes a consistent decay rate throughout the unobservable past, is to suggest potassium, argon, carbon and uranium have all adjusted decay rates at the same rates.
Think of it like three cars setting off at different speeds (different decay rates), and all three changing speeds whether it's faster or slower (changing decay rates) but all three cars being neck and neck when they come into view (modern observations)
Some people who disagree with the evidence for an old earth but couldn't deny the evidence suggested the possibility that there were twenty something global catastrophes that would account for this evidence.
Giants causeway
Hell's gate
Eye of the sahara
Crystal cave, Mexico
Fingels cave, Scotland
Devils tower
Stone forest
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