Human and earth interaction Flashcards
What is the equation for the world population growth rate?
WPGR = (BR - DR) *100%
What was the growth rate in 1900 vs 1960 vs today?
1900 - 0.8%
1960 - 2.6%
Today - 1.05%
Define what doubling time means
this is the time required to double a human
population at a given growth rate.
What is the rule of 70?
Population doubling time = 70 divided by growth
rate.
At world growth rate of 1.05% 70/1.05 = 67 yrs to double the population.
Define non-renewable resources
Resources that cannot be renewed within a humans lifespan are considered to be non-renewable.
What are some ways we can get more use out of non-renewable resources
Mines for uranium, potash, and copper (take millions of years to form)
We can recycle them though to make it more reusable
Fracking to recover more oil from the ground
define feedback loop
outputs (e.g., more sewage waste)
influence the performance of the system (e.g., more
sewage waste getting into drinking water, more
disease)
Earth as a ‘closed system’ with feedback
loops as resource availability changes,
Gaia hypothesis (proposed by James
Lovelock in the 1980s)
Define positive feedback loop
increases a quality of the system
define negative feedback loop
Dampens a quality of the system, keeps the
system more stable
What are the 6 geological eons?
Beginning: Hadean, Archean, Proterozoic, Paleozoic, Mesozoic, Cenozoic.
The first 3 are contained in the Precambrian eon and the last three are contained in the Phanerozoic eon.
How are the boundaries between the eons, eras, periods determined?
Events such as new fossils, disappearance of fossils and major events like meteor impacts
How do geologist reconstruct earths geological history?
They study the rock record: stratigraphic record and fossil record
Define Stratigraphic record
the layers of
rock and their relationships to one
another
Define formation
A formation is a rock layer of the same rock type * or group of associated rock layers that occur over a larger
area and have a specific geologic age
Define contact
The surface/ boundary between 2 formations
Define strata
Layers of sedimentary rock
Define Stratigraphic column
a vertical cross-section where the rock
layers are divided into stratigraphic formations.
In order to understand the history of a rock, geologists use several geological principles. What are the 8?
- Uniformitarianism
- Original horizontality
- Law of superposition
- Lateral continuity
- Cross-cutting relationships
- Fossil succession
- Inclusions
- Unconformities
Define uniformitarianism
processes operating at the present are the same processes that
have operated in the past.
define catastrophism
was an earlier theory, generally not
the way Earth’s surface has evolved but catastrophic
events have been important sometimes.
* For example, Asteroid impacts