why we study marine biology
provide clues of early life on earth
origin of products
oxygen production
recreation and tourism
climate regulation
marine biology
the study organisms that live in the sea
marine biologist
studies the organisms that inhabit the sea
oceanographer
mainly study physical non-living aspects of the ocean
charles darwin
sailed on HMS beagle
primary goal of cartography
produced many scientific writings
principle of natural selection and evolution
the challenger expedition
1872-76
first systematic survey of the world ocean
remote sensing
satellites are used to study large expanses of the ocean surface
sonar
maps seafloor depths and formations
scuba
used to study the marine environment for longer periods and at depths otherwise unavailable to humans
remotely operated vehicles (rov)
allows for direct exploration of the marine environment when scuba is not an option
research vessels
floating labs for oceanographers and marine biologists to explore the environments for long periods of time
argo floats
international program that collects information from inside the ocean
scientific method
group of techniques used to approach experimentation and answer questions about the natural world
steps of scientific method
observation/question
hypothesis
test/experiment
collect/analyze data
conclusion
hypothesis
testable statement constructed from observations and reasoning, both induction and deduction. must be worded so it is testable by scientific means
controlled experiment
when testing a hypothesis, researchers must look at only one factor at a time
scientific theory
hypothesis that has been tested repetitively over time by many people without being disproved
core
innermost layer
solid inner and liquid outer
iron-rich
pressure is more than a million times earths surface
4000 celsius
mantle
middle layer
very hot - near melting point of rock
semi-plastic composition
flows like liquid
crust
outermost layer
thinnest portion of the earth
rigid floating on mantle
oceanic and continental
oceanic crust
basalt
more dense
younger than, -200 million years
continental crust
mostly granite
light colored
less dense
older (some 3.8 billion years)
alfred wegner
proposed the idea of pangaea
continental drift
idea of pangaea proposed by alfred wegner
pangaea
continents had been joined in a single supercontinent
plate tectonics
covers earths surface
moves ocean floors
convection currents assist movement
heat from the mantle drives currents
mid-oceanic ridges
chain of submarine volcanic mountains that rise from the ocean floor and encircle the globe
island arcs
chains of islands found throughout the oceans, especially in the west pacific
lithogenous sediments
derived from the physical and chemical break-down of rocks
biogenous sediments
derived from skeletons and shells of marine organisms including diatoms, radiolarians, foraminiferans, and coccolithophorids
continental margins
boundaries between continental and oceanic crust
continental rise
formed by sediments that have been pushed down from the continental shelf and slope
active margins
sites of more intense geologic activity including earthquakes, volcanoes, and trenches
characterized by steep, rocky, shorelines, narrow continental shelves, and steep continental slopes
passive margins
relatively inactive geologically
characterized by flat, wide, coastal plains, wide continental shelves, and gradually sloping continental slopes
abyssal plain
deep-sea floor
central rift valley
gap/depression at the center of ridge where the plates are pulling apart
hydrothermal vents
heated water that forces its way back through the crust and emerges
cohesion
sticking together of particles of the same substance
surface tension
property of the surface of a liquid that allows it to resist an external force, due to the cohesive nature of the water molecules
salinity
total amount of salt dissolved in water