Geology Flashcards
Lt. Matthew Fontaine Maury
1842-1870s Head of US Navy hydrographic office First marine geologist First deep marine bathymetric map (N Atlantic) MAR circa 1855 Telegraph Plateau Soundings for laying telegraph line
Challenger Expedition
1872-1876 Charles Wyville Thomson, prof @ Edinburgh convinced royal society of London to let them go Circumnavigated globe 362 stations 500 (492) soundings dredge, cored rock and sediments collected water samples measured temperature, salinity, currents
WWI
Echosounding helped to hear enemy subs
German meteor expedition
1925-1927 First to use continuous recording echosounding to study the seabed
Maurice Ewing
in 1948 Founded Lamont-Doherty Geological Observatory (LDGO) led to theory of plate tectonics
Bruce Heezen and Mary Tharp
Map of the entire ocean floor published in 1977

Alvin
Research Sub
built in 1964
Max depth 14,000ft (4000m)
Deep Sea Vent Communities
Discovered in 1977
Pacific
JOIDES
Joint Oceanographic Institues of Deep Earth Sampling
1960s-1980s
Glomar Challenger
Drilled 624 sites
confirmed valididty of seafloor spreading and plate tectonics
continued with Ocean Drilling Program (ODP) in 1985
Deepsea Drilling Project
1960s
started with Glomar Challenger
JOIDES Resolution
successor of the Glomar Challenger
operated in the International Ocean Drilling Program (ODP)
1985
Can drill 5 miles below ocean surface
500 wells
Integrated Ocean Drilling Program
IODP
2003-2013
multiple platforms
refurbished JOIDES Resolution, Chickyu
GPS
Fully operational in 1994
DOD funded for missile launches
degraded until 2000, then available to everyone
GLONASS
Russian Global Navigation Satellite system
incomplete coverage until about 2004
Satellites
have a clock set to exactly the same time and know their exact position
trasmits position and time signal
GPS recieves signal, delayed by distance travelled- difference is calculated and the distance to each satellite is calculated
for precise GPS location
need 4 satellites
the atomic clock is on the satellite, not on handheld.
the 4th satellite provides the atomic clock component
Sampling the bottom
grab sample
gravity core and Kasten core
Piston core
vibracore
Pneumatic hammer coring
rotary drill core
Grab sampler
Not representative of the bottom
gravity corer
top of the core gets disturbed, good for bottom seds
Kasten core
type of gravity core, but rectangular
has a liner
have to process on the ship
much larger sample and less disturbance
Piston Coring
method of choice
Freefalls a known distance dependent upon material
creates a vacuum right at sample at the surface so the core isn’t disturbed

Vibracoring
Deep water or shallow
vibrations liquify material and buries it
pneumatic hammer coring
tower of power
very efficient- 20 in one day



































