EARTHSCI 3 Flashcards
im gonna kms
who thought that Earth has been in perpetual existence?
Aristotle
who thought that Earth had not existed for a long time
Lucretius
Who believed that the Earth was made in 4004 BC
James Ussher
who formulated the modern concepts of deposition of horizontal data
Nicolas Steno
Historical events can be sequenes from outcrops of …
sedimentary layers
who proposed the principle of uniformitarianism
James Hulton
physical, chemical, and biological processes that work today are the same forces that have worked in the geologic past
Principle of Uniformitarianism
tectonic plates remain unchanged through time and they only vary through
intensity and frequency
Geologists used observational evidence, and suggested that Earth was how old?
100 million years old
The development of ___________ that radioactive dating was used to date the earth
Modern quantum mechanics
This was adapted by the National Academy of Sciences resulting in the discovery of Earths age, which is 4.5 billion years old
radiometric time scale
study of rock layers and radiometric dating
stratigraphy
what are rock layers called
strata
method of showing the sequence of events
Relative Dating
most of the rocks exposed on the surface are what kind of rocks
sedimentary
If the rocks are no longer horizontal, then….
they are already disturbed by the forces within
how is the sequence of solid particles that settled on the seabed determined
weight
heaviest _____ lightest _____
first, last (bottom, up)
each layer is older than the one above it and younger than the one below it
principle of superposition
deposited in flat layers, not yet disturbed and still has its original horizontality
principle of original horizontality
slab of rock/ magma intrudes into a rock, that fault, dike, or magma is younger than the rock
principle of cross-cutting and relationships
rock mass that contain pieces of are that are younger than other rock masses
inclusions
rock layers formed wihtout interruption are conformable
principle of uncomformities
deofrmed or eroded before another layer was deposited; mismathced
unconformity
sedimentary layer that is deposited over an ore erode horizontal sedimentary layer
disconformity
sedimentary layer that is folded, titled, etc
angular unconformity
sedimentary layer that is desposited over an eroded igneous or metamorphic rock
nonconformity
why is rock correlation important
to develop a geologic time scale
rock correlation is only applicable to _______
short distances due to vegetation and soil
remains of plants of extinct animals embedded in sedimentary rocks
fossils
science that deals with the study of fossils
Paleontology
actual remains that did not change through time
true form fossils
fossils turned into stone
petrified fossils
preserve the form and shape of organisms
mold and cast
gases and liquids leave animal form due to pressure leaving behind a thin layer of carbon
carbonized fossils
hardened resin of ancient trees
amber
who made the principle of fossil succession
William Smith
fossils of organisms that lived only for a short period of time and are found in most places of the planet
Index fossils
actual date or date range in number of years
absolute dating
how are absolute dates obtained
through radioactive and radiometric methods
same protons different neutrons
Isotopes
parent isotope decreases, daughter isotope ______
increases
the rate of change of a radioactive element is measure in
half-life
use of decay of carbon-14, an isotope of carbon, to date events in the past
radiocarbon dating
radiocarbon works best with what type of rocks
igneous and metamorphic
are the series of time intervals on a geologic time scale equal or unequal
unequal
largest intervals of geologic time with duration of hundreds of millions of years
Eons
4 eons
Hadean, Archeozoic, Proterozoic, and phanerozoic.
eons smaller divided groups
eras
eras are subdivided into
periods
smaller subdivisions of the Cenozoic era
epochs
informal name gives to the first three eons of the geologic time scale
Precambrian
known as the rockless eon because no more rocks in this eon exist today
Hadean
4 eras of archean
eoarchean
palaeoearchean
mesoarchean
neoarchean
single-celled organisms what eon
archean
3 eras of proterozoic
paleoproterozoic
mesoproterozoic
neoproterozoic
what was the big landmass that was formed due to the joining of continents in the proterozoic eon?
rodinia
supercontinent Pangaea was formed
Paleozoic era
first life forms with parts
phanerozoic eon
“Age of trilobites”, shallow seas covered parts of the continents and mild climate existed. Rodinia began to break
cambrian period
many volcanoes and mountains, primitive plants, first corals
ordovician period
caledonian mountains were formed, rise in sea level worldwide
silurian period
erosion of mountains resulted in the deposition of much sediment in seas. Age of fishes, fishes and terrestial plants became abundant
devonian period
first winged insects appeared, appalachian mountains
Mississippian period
first reptilesm derms mayflies and cockroaches
Pennsylvanian period
age of ammphibians, ended with the larges tmass exctinction
permian period
