Lecture 1 - Time Travellers

Question 0

James Hutton (1726 - 1797) realised what about the Earths surface?

Answer 0

That there was cycles in the formation of Earth = it must of taken a long time to come about

Question 1

James Ussher (1581-1656) Archbishop of Armagh made an attempt of dating the Earth? At what time, date an what were his conclusions?

Answer 1

23 Oct 4004BC, 9am morning

Climate change came through the great biblical flood

Question 2

What did John Woodward (1695) argue?

Answer 2

Fossils were organic remains of former living creatures.

This meant ancient life was destroyed in the great biblical flood

Question 3

William Smith was a canal builder, what did he recognise and construct?

Answer 3

He recognised the strata or layers of rocks from the fossils they contained

Correlated this to produce the first geological map of England and Wales

Question 4

A fundamental principle of stratigraphy was outlined by a Persian Scholar, Avicenna in the 11thC, who was it defined by and what year?

Answer 4

Dane Nicolas Steno in 1669

Question 5

Dane Nicolas Steno outlined 3 principles of stratigraphy what were they?

Answer 5

1. all rocks can be deprecated into strata (layers) based on when they were formed
2. The oldest formed first = at bottom
3. Youngest formed last = at top

Question 6

Prof Charles Lyell (1797-1875) defined what?

Answer 6

‘Uniformitarian’ philosophy

Question 7

What did the uniformitarian philosophy outline?

Answer 7

All processes observed today on earth e.g, action of rivers, uplift and subsidence of land occurred in the past . Aka the laws of nature are constant

The present is the key to the past

Question 8

What was an early method to attempt dating the Earth (Hint: heat)

Answer 8

Calculating heat loss from the planet

Question 9

How old did William Thomson (1824-1907) calculate the Earth to be?

Answer 9

20-40 milli years bruv

Question 10

Antonine Henri Becquerel (1852-1908) had a photographic plate what did it show?

Answer 10

Uranium salts showed exposure to radiation, there was a metal cross between the plate and uranium salt

Question 11

What did Marie Curie ?1868-1934) show?

Answer 11

Thorium had similar properties to uranium

Question 12

What did Ernest Rutherford and Frederick Soddy first propose?

Answer 12

Radioactive elements were unstable and changed over time

Question 13

What are radioisotopes?

Answer 13

Isotopes that are unstable

Question 14

What do radioisotopes do?

Answer 14

Transform spontaneously into another element, emitting a radioactive subatomic particle

Question 15

Spontaneous radioactive decay occurs at a measurable rate, what are the producing values called?

Answer 15

The producing values are called ‘half-lives’

Question 16

How are half lives defined?

Answer 16

The period of time for half the original atoms to decay to daughter products

Question 17

The oldest rocks in the world dated using the decay of radioactive elements, name 2 of these?

Answer 17

1. Barberton Greenstone Belt, South Africa - 3.5 billion years old
2. Isua Hills, Western Greenland, 3.75 billion years old, contained fossil bacteria some of the oldest life forms on Earth

Question 18

Conclusion: Over many centuries scientists have realised the earth is changing, where did evidence come from?

Answer 18

Rocks and fossil records

Question 19

Conclusion: what did Charles Lyell outline in his theory of uniformitarianism?

Answer 19

Gradual change in the landscape over millions of years

Question 20

Conclusion: many attempts were used to calculate the age of the Earth, ageing 4.5 billion years over the past 3 centuries. What was used to provide the absolute age?

Answer 20

Radioisotopes