Week 1 Flashcards
Natural Processes
Events that are directed by physical, chemical and biological activity such as earthquakes, eruptions, hurricanes etc.
Natural Hazards
- When a natural process becomes a potential threat to life or property
- We cannot control
- Sometimes we make them worse (global warming)
Disaster / Catastrophe
When a natural hazard follows through with the threat
Natural Disaster
A sudden or great misfortune, a calamity
Local Disaster
A significant disruption to local society and communities, but the consequences are contained locally
Regional Disaster
The magnitude of disruption is greater – something greater than a single city area might occupy, and the consequences of the event are more widespread.
Regional Catastrophe
- A disruption of sufficient magnitude that large regions such as provinces, states or even countries
- Must deal with consequences, including death and numerous injuries to the regional population.
Global Catastrophe
The magnitude of the disruption is felt – and dealt with – on a global scale; death of many whole species is common.
Nicholaus Steno (1638-1686)
- Danish natural philosopher
- One of the first to try and understand the Earths surface
- Relied heavily on the study of rocks
Stratigraphy
Study of the layers of rocks and sediments
Thomas Burnet
- Was deep thinking with Steno at the same time
- Anglican clergyman (confessor to King William
Archbishop Ussher
- 1650 pronounced that earth came into existence in at sunset of October 22nd 4004 BC
- Found this out by going through all close examination of official documents and the bible
Catastrophism
An attempt to recognize the importance of geological processes, but sequence them and confine them within the concept of biblical studies
Baron Georges Cuvier
- Taught the sequences of geological formations
- Head of the prestigious academy of science
If you were a ‘catastrophist’, you believed
- The history of Earth was a record of unique events
- That there was no such thing as natural evolution of anything – biological or inorganic
- That there was no possible prediction of nature.
James Hutton (1726 – 1797)
- First person to acknowledge Steno’s work and formulate a concept from his work
- Known as the father of modern geology
- Wrote a book called theory of geology and introduced the concept of gradualism
Charles Lyell (1797 – 1875)
- Wrote a book called principles of geology
- Championed Hutton’s hypothesis and emphasized the concept of unlimited geological time
Age of Earth
- Began in Europe in the 17th century with the help of Archbishop James Ussher using his research skills of important official documents while studying the deaths and births in the bible.
- He said earth was created 4004 BC which means it would only bee just over 6000 years old, Christian culture
- In the Maya calendar it was estimated to be 400 million years old
- In the Hindu calendar it was estimated to be 2 billion years old
- Oldest matter was found in meteorites aged 4.567 billion years old
- Hard to say how long it took to build earth but definitely was underway
Nicholas Steno proposed 3 principles that form the basis of all geologic mapping
- Principle of Cross-Cutting Relationships
- Principle of Superposition
- Principle of Faunal Succession
Principle of Superposition
The ordering of the layer,
the layer at the top is the youngest. Before any complications
Principle of Cross-Cutting Relationships
- A fault is younger than the youngest rock it cuts
- The strata above an unconformity are younger than the strata below
- Any feature that cuts across a rock must be younger than the rock it cuts
Principle of Faunal Succession
Finding missing layers of sediment based on nearby by fossil and sediment
Eras
Palaeozoic (Ancient life)
Mesozoic (Middle life)
Cenozoic (Recent life)
Precambrian (before Paleozoic)
Relative Age Dating
- Sedimentary rock layer are deposited on top of each other
- The layers are flat lying when they are deposited
- They are deposited over wide areas
Radioactivity
- The progressive breakdown or decay of the nucleus of an atom or isotope
- Every unstable or radioactive isotope decays a its own characterizes rate
