EARTH 222 Study Guide - Fall 2018, Comprehensive Midterm Notes - Lithosphere, Continental Crust, Transform Fault
12 Oct 2018
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Department
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EARTH 222
MIDTERM EXAM
STUDY GUIDE
Fall 2018
Monday, September 10th Lecture Notes: Geological Oceanography (weeks 2-5)
• Earliest explorers
o Evidence for homo erectus living on indonesian island (>750,000 years old) -
required crossing deep channel
▪ Must have had some kind of boat or vehicle to get there and settle on that
island
o Bones of marine fish in stone age settlements (~40,000 BCE)
o Cave paintings suggest primitive boats in use by ~6000 BCE
• ***Only indirect proxy evidence - no written record - creative
interpretation about ocean exploration - suggested use***
• Early ocean-going exploration
o Occurred primarily in mediterranean and Polynesia
▪ Mediterranean
• Minoan civilization - first recorded civilization to use boats (~3000
BCE / 5000 years ago)
o Trade, transport, defense, and conquest
o Dominated Aegean Sea region in terms of these aspects^
• Phoenicians next great sea power (1100 to 850 BCE)
o What is now Israel, Syria, Lebanon
o Voyaged as far north as British Isles
• Greek mathematician Pythagoras declared earth was round 550
BCE - debate over whether he was first or not
• 450 BCE - Herodotus made one of the first high quality maps of
the world
o Reasonable representation of latitude
o distorts longitude
o Pomns Euxinus
▪ Euxinic = anoxic + sulfidic
▪ Descriptive of black sea today, but was more
common back in the day
• Greek geographer and explorer Pytheas (4th century BCE)
o Used polaris to develop method of using latitude
o Explored british isles, norway, maybe iceland
• Greek geographer Ptolemy (150 BCE)
o Used incorrect value for earth’s circumference
▪ Reason why columbus thought he landed in Asia
▪ Polynesian explorers
• Used double hulled canoes made from wood and reeds and used
them to explore the pacific
• Polynesians moved from mainland china possibly taiwan in a
south east direction - moving from island to island until they
populated the western pacific islands (2500 BCE - similar to
minoans)
• Subsequent migration to Samoa, Tahiti, and Marquesas (by 200
BCE)
• Had to go out into the open ocean, couldn’t just follow the coast
and never be far from land
find more resources at oneclass.com
find more resources at oneclass.com
• Had to use other techniques - stars, wind / wave patterns, clouds,
and seabirds
• Distance that they would have had to travel was around 8000km -
like sailing a pontoon boat from Lake Michigan to France
o How did early ocean explorers know where they were?
▪ Coast line
▪ Dead reckoning
• Distance and direction from starting point
• Step by step navigation
o Depends on how well you can estimate direction and
distance traveled
• Ex. columbus and dead reckoning
o Set his compass to go straight west and then would
estimate how far he went in a day based on speed *time
o Dropped rope and counted how many knots went past in a
fixed amount of time - doesn’t take into account current or
sideways motion
• Distance = speed * time
• Errors accumulate over time
• Latitude and Longitude
o Latitude - define north south direction
▪ 90 degrees latitude north and south
▪ Equator
o Longitude - define east west direction
▪ 180 degrees east and west
▪ Prime meridian - 0
o Each degree of latitude and longitude is divided into 60 minutes and each minute
into 60 seconds
o Now, with GPS this is recorded in decimal form (decimal degrees)
▪ 1 degree is equal to 60 minutes and 3600 seconds
▪ One minute is equal to 1/60 degrees
▪ One second is equal to 1/36000 degrees
• D, m’,s” (ex. 40 16’ 36.5” N)
• The decimal degrees dd is equal to
o dd=d+m/60+s/3600
o Nautical mile is equal to precisely 1 minute of latitude
▪ Each degree of latitude contains 60 nautical miles (n/s)
▪ Each degree of longitude contains 111 nautical miles (e/w) at the equator,
but less at high latitudes
• How many at the north pole?
o Estimating latitude with Polaris (north star)
▪ It is so far away (430x10^13 km) that its light is essential coming from due
north
▪ If you are at the equator and you try to look at the north star they can’t
see it because it is at 0 degrees
▪ If you are at the north pole the angle is 90 degrees
▪ If you are in the middle you can see the horizon and still see the north
star at a 42 degree angle
▪ Last star on handle of the little dipper is the north star
o The longitude prize - not as easy to determine - no polaris trick
find more resources at oneclass.com
find more resources at oneclass.com
