Terms in this set (163)
a crisis that affects life right across the planet from the depest oceans to the highest mountains
Two types of biosphere
Hydrosphere (Oceans, lakes and rivers)
Lithosphere (the earth's crust)
1. Which of the following statements is TRUE?
A) The lithosphere does not interact with the biosphere.
B) Ecosystems are only composed of land based creatures.
C) The biosphere is only composed of plants.
D) Plants often form the base of ecosystems.
E) The biosphere is composed of the atmosphere and the hydrosphere.
Five principles of biostratigraphy
- Original Horizontality
- Lateral Continuity
- Cross-Cutting Relationships
- Faunal Succession
The Principle of superposition
When artifacts are found in rock or earth that is layered, the deeper layers hold the older artifacts.
CYU EX.2 Check Your Understanding
The annotated image of Siccar Point, Scotland (below) describes important events in its geological history. Which event is the YOUNGEST?
A) the deposition of the desert rocks
B) the deposition of the deep ocean rocks
C) the tilting of the deep ocean rocks
D) the erosion of the deep ocean rocks to form the unconformity
E) it is impossible to tell
Principle of Original Horizontality
The principle that states that layers of sediment are generally deposited in a horizontal or nearly horizontal position.
Principle of Lateral Continuity
sediments generally accumulate in continuous sheets within a given region
principle of cross-cutting relationships
younger features cut across older features
If it cuts through, it's probably younger
Principle of Faunal Succession
Within any layer of rock (stratum), different types of fossils succeed one another in the same relative order
CYU EX.3 Check Your Understanding
1. The principle of faunal succession can be used to correlate rocks because ______. (select the MOST appropriate answer)
A) all sedimentary rocks were originally horizontal
B) the biosphere is composed of ecosystems
C) life and the biosphere have evolved over time
D) dinosaurs evolved in the Mesozoic
E) unconformities may cross-cut older rocks
2. Which of the following fossil ranges would provide the greatest RESOLUTION in biostratigraphy? A fossil species that ______.
A) is found throughout the Phanerozoic
B) is found throughout the Paleozoic
C) evolves and goes extinct in the Cretaceous
D) evolves in the early Mesozoic and goes extinct in the late Mesozoic
E) evolves in the Cretaceous and is still found today
CYU EX.4 Check Your Understanding
1. Refer to the diagram below of a geological section. Of the following, which is the oldest event or feature?
A) the rocks at A
B) the igneous intrusion C
C) the rocks at D
D) the erosion surface E
E) the fault F
CYU EX.5 Check Your Understanding
1. Refer to the diagram below of a geological section. If igneous rock 2 (the "v" symbols) is dated at 540 million years old and igneous rock 3 (the "x" symbols) is dated at 70 million years old, where might you be able to find dinosaurs on this geological section?
A) sections 1 and 6
B) sections 4 and 5
C) sections 1 and 4
D) section 1 only
E) section 4 only
CYU EX.6 Check Your Understanding
Who of the following believed the Earth to be around 6,000 years old?
Time scale of Earth
Why Precambrian when compared to Phanerozoic, is far less subdevided?
Although it represents the majority of Earth's history, an extraordinary proliferation of fossils at the base of the phanerozoic in a period called the CAmbrian
broad subdivisions that are particularly significant
The most recent eon, an interval of time from 543 Ma to the present.
The emergence of creatures with hard parts and the base of the Mesozoic and Cenozoic, which are based on the emergence of new species following a mass extinction
CYU EX.7 Check Your Understanding
1. Which of the following would best represent the relative distribution of time between the Precambrian and the Phanerozoic?
2. Which of the following events in Earth's geological history could NOT have occurred over a 200-million year period?
A) opening and closing of oceans
B) fragmentation of supercontinents
C) evolution then extinction of whole groups of species
D) sediments being turned into rock, tilted, then eroded
E) ALL of these processes/events could occur over a 200-million year period
CYU EX.8 Check Your Understanding
Which of the following would be considered a MASS EXTINCTION? The extinction of ______.
A) all ladybug species over 10 years
B) 20% of all species over 90,000 years
C) 80% of species over 10 million years
D) 90% of species in temperate rain-forests
E) 45% of all species over 500,000 years
The definition of a mass extinction
- at least 30% of Earth's species much be lost
- across a broad range of ecologies
- a short/sudden duration (around 1 million yrs maximum)
5 major extinction (Big Five) in the Phanerozoic
Cretaceous / Paleogene (K/Pg), 65 Ma
Late Triassic, 205 Ma
Permo / Triassic (P/T), 251 Ma
Late Devonian, 360 to 375 Ma
Late Ordovician, 440 to 450 Ma
CYU EX.9 Check Your Understanding
1. Which of the following global event is used to DEFINE the end of the Mesozoic?
A) a large impact crater
B) a change in climatic conditions
C) a period of intense cold followed by a period of very warm conditions
D) the death of the dinosaurs
E) the extinction of many species and subsequent radiation of new species in the Paleogene
2. Which pair of extinction events "bracket" the time of the dinosaurs?
A) Late Ordovician and Permo-Triassic
B) Late Devonian and Late Triassic
C) Permo-Triassic and Cretaceous-Paleogene
D) Late Devonian and Cretaceous-Paleogene
E) Late Devonian and Permo-Triassic
The cause of mass extinctions
- Biological causes
- Earth-based cases
- Extraterrestrial impact
- Combination of many factors
the details of biological causes
- excessive predication
- changes in continental configuration
-- changes in climate, ocean cyclicity, sea level
-- the greater the landmass the lower the diversity
- changes in the atmosphere
Which of the following would NOT be considered a "Physical Earth-based" cause for a mass extinction event?
A) an extremely extensive volcanic event
B) warming of the atmosphere due to an increase in greenhouse gases
C) decreased circulation of the oceans
D) spread of a virus that kills 90% of plant life
E) extensive glaciation of all major continental areas
A Case study: the Permo-Triassic Extinction
The possible reasons:
1. Continental configuration: drop in biodiversity
2. Sea level fall: less ocean ridge activity
3. Oceanic stagnation
4. Climate change
5. Siberian Traps: massive volcanic activity in Russia
6. Possible impacts
a lack of oxygen
layer of gases surranding the lithosphere
Degree of variation of life forms within a given species, ecosystem, biome or planet
Global sum of all ecosystems
Correlation of rocks using fossils
oldest period of the Phanerozoic/Palezoic
The most recent grouping of geological periods in the Phanerozoic
matching geological sectiosn that might be separated by large distances
youngest period of the Mesozoic
method of deduction of relative age of geological sections witch says "if it cuts through, it's probably younger"
established concept of extinction
Understanding the extreme age of Earth
GEological period in the Palezoic
Earth System Science
understanding Earth as an interaction of many systems
a collection of living organisms that interacts with the Earth System
theory to explain biodiersity and emergence of new species
death of every member of a species
change in fossil species over time
basalt lava produces by very large scale volcanic activity over a period of 100s of thousands of years to a million years
Microfossils that commonly secrete a calcium carbonate shell
length of geological time a species existed on Earth
Giga annum: billions of years ago
cold climatic periods marked by the advance of glaciers
Southern part of pangaea
gases in the atmosphere that contribute to global warming
Scottish geologist; used cross cutting relationsihps in Earth age studies
All Earth's liquid water
outer layers of the Earth including the cust and uppermost mantle
Mega annum; millions of years ago
Grouping of geological periods; oldest triassic yougest Cretaceous
all fossils just at the limit or smaller than can be seen by the naked eye
a period in the Paleozoic
a stratographic principle which says if its tilted or folded, then it was originaly flat
oldest geological period of the Cenozoic
A grouping of geological periods; the oldest grouping of the Phanerozoic
large landmass that existed during the Permian
Geologial time divisions
a geological period; youngest period in the Paleozoic
Grouping of all geological periods after the precambrian
grouping of all geological periods older than the cambrian/phanerozoic
the emergence of new species follwoing a mass extinction event
English engineer who developed the concept of faunal succession
Danish anatomist who developed the principles of stratigraphy
layers of sedimetary rocks or lave flows
study of the manner in which strata are laid down
a landmass comprising of more than one continental core
stratigraphic principle which say what is on top is yougest
pldest geological period of the MEsozoic
An erosion surface separating two rock masses of different afes
Archbishop of Armagnac who believed Earth was created in 4004BC
The Cretaceous-Paleogene (K/Pg)
CYU EX.11 Check Your Understanding
Which of the following statements regarding the degree of extinctions around the K/Pg boundary is TRUE?
A) Over 95% of species went into extinction.
B) All creatures larger than 25 grams went into extinction.
C) Around 80 to 90% of marine species went into extinction.
D) It only effected land based creatures.
E) It only effected ocean based creatures.
who brought the features of the K/Pg extinction to the world's attention
Louis and Walter Alvarez
is rare in earth, but high in meteorites
is known to exist in higher concentrations in extra-terrestrial objects such as asteroids
Evidences of Alvarez findings
1. Fern spores vs. pollen
3. Shocked quartz
4. Tsunami deposits
Fern spores vs. pollen
an increase in fern spores relative to pollen. THis suggests that global forest fires may have raged at the end of the Cretaceous leaving a landscape open for ferns to spread
Natural glass produced by melting rocks during an impact event
Many of them are found at the K/Pg boundary in many different locations
Quartz deformed along planes called shock lamellae
fractures in quartz,only form in response to extremely high pressures, found in KPg boundary clays, likely formed by force of impact
found in MExico, TExas, New Jersey
If you were looking for evidence of ancient major global forest fires, what might you expect to find in the sediments?
A) high concentrations of iridium
B) a high proportion of fern spores
C) the quartz in the sediments would show "cross-hatched" features
D) a high proportion of pollen
E) tear- or hershey kiss-shaped structures composed of natural glass
Chicxulub Impact Crater
• 180 km across
• thick layers of tsunami deposits, shocked quartz and tektites
• thicker towards crater
Consequences of the Chicxulub Impact Crater
1. Initial effects
2. Long-term effects
• fireball & vaporization
• widespread forest fires
• nearly global tsunami
Long term effects
a. temprature changes
- Cold House (wks-mths)
- Raise in temperature
- Hot House
b. Acid rain
high-energy blast causes to form oxides of nitrogen -> becomes nitric acid
CYU EX.13 Check Your Understanding
Which of the following may have been responsible for the acidification of oceans and land surfaces following the Chicxulub Impact at the end of the Cretaceous?
A) formation of oxides of nitrogen
B) vaporization of limestone
C) vaporization of ejecta
E) death of non-avian dinosaurs
CYU EX.14 Check Your Understanding
Consider this statement:
"The Siberian Traps was an area of intense basaltic volcanic activity at the end of the Cretaceous, and is thought to have had serious consequences for the health of the biosphere."
Which of the following is the MOST APPROPRIATE response to the statement above?
A) The statement would be true if the volcanic activity referred to was that in the Deccan area of India NOT in Siberia.
B) The statement is NOT true because the Chicxulub impact was entirely responsible for the extinction event at the end of the Cretaceous.
C) The statement is accurate.
D) The statement is UNTRUE because there is no recorded volcanic activity at the end of the Cretaceous.
E) The statement would be true if it referred to the End Ordovician and NOT the K/Pg extinction.
Extinct group of marine creatures related to squid and octpus
Globally cold climatic condition
any depression in the ground resulting from a high velocity impact
a group of vertebrates common during the Mesozoic
material ejected from a creater during an impact
rocks produced by the evaporation of standing bodies of water
the feeding relationships between species in a biotic community
the physics of geology; commonly used to study subsurface features
studying variations in Earth's gravity to reveal subsurface features
A mineral rich in sulfates; common in evaporite sequences
globally warm climatic conditions
A rock composed of calcium carbonate
tiny creatures floating in the water column; often the base of oceanic food chains
cold period after a nuclear war caused by dust/soot/smoke in atmosphere
process by which plants use light to convert COs into organic compunds
stress lines in quartz crystals generated by high energy events
a reproductive structure adapted for dispersal
Two general types of impacts from the space
Material left over from the formation of the Solar System and are composed of icy material and other debris - effectively "dirty snowballs" in space
Two examples of comet
comes into view of the Earth every 74 to 79 yrs
A comet that appeared in 1997 that was bright enough to see with out a telescope
This will return in 2,380 years
Leonid Meteor Shower
- one of the two best meteor showers each year
- radiant is found in the constellation Leo
Two comet stores in the Solar System
The Kuiper belt
The Oort cloud
The Kuiper belt
exists in an area from about the orbit of Neptune to about 50 au's out
The Oort cloud
a cloud of comets that exists way beyond the Kuiper belt and is only weakly associated with our Sun
mostly found in a belt between the orbit of Mars and Jupiter
CYU EX.15 Check Your Understanding
At which location would you expect to find the majority of asteroids in our Solar System?
How many objectives enter our atmosphere every 24 hours
the hypotheses that have been proposed to account for the Raup-Sepkoski periodicity
- Nemesis-Companion Star
- Planet X
- Movement Through the Galactic Plane
Nemesis - Companion Star
our Sun has a companion star way beyong the outer limits of our solar system whose orbit brings it close t the Oort cloud every 25 m yrs
This could cause shifts in the Oort cloud as it orbits around the Sun
Movement Through the Galactic Plane
Every 25 million or so, we pass through the densest part of the galaxy, which contains a higher number of stars and also the most gravitational effects
The periodicity in extinctions proposed by Raup and Sepkoski is thought to be related to ______.
C) sea level change
What is the potential risk of you being killed by an impact event?
A) 1: 200
B) 1: 2,000
C) 1: 20,000
D) 1: 200,000
E) 1: 2,000,000
How does this compare with your risk of being killed by a car crash? an airplane crash? an earthquake?
Recent History of Impacts
Tunguska, Siberia: Jun 30 1908
Shoemaker LEvy 9 IMpact with Jupiter in 1994
Mar 22, 1989 - miss earth by 6 hrs
Mar 19 1996 - miss earth by 430k km
Mar 2 2009 - 70k from Earth
Nov 7 2011 - 324,900km
Jun 2, 2018 -
The Tunguska event is notable in that it ______.
A) produced a crater 180 km across
B) was responsible for the extinction of many Siberian species
C) is associated with other impact craters in France and Canada
D) left no impact crater
E) caused a large tsunami in the Black Sea
A defense plan
scale/method for categorizing impact hazards
Impact Mitigation Strategies
Sudden Orbit Adjustment
Steady State Orbit Adjustment
Destroy an approaching impactor with nuclear weapon
Sudden Orbit Adjustment
exploding a nuclear warhead in front or on the surface of an approaching body to adjust its trajectory so it is no longer an impact threat
Steady State Orbit Adjustment
require more warning time
a. attached chemical/nuclear rock to the object to gently nudge it out of the way
b. Deploy robot to land on the surface of the object. change the approaching object's trajectory
c. ablation systems
d. attach large solar sails
CYU EX.19 Check Your Understanding
What is the MOST important factor in preventing a possible impact on Earth?
A) knowing the composition of the asteroid or comet
B) having enough warning time
C) knowing the speed of the impactor
D) knowing the possible angle of impact
E) knowing the possible location of the impact
the removal of a body part or the destruction of its function
a detonation in the atmosphere
a Solar System body larger than a meteoroid, but smaller than a planet; does not have a tail
a region of space within an extremely powerful gravitational field
a small Solar System body that exhibits a tail as it passes close to the Sun
the area of the galaxy that is most densely packed with stars
a massive gravitationally bound collection of stars and other matter
gravitation field produced by a large body; other space bodies or objects can fall into this well
anything from outer space that might impact Earth's surface
a ring of small Solar System objects including comets
process of removing material off a large space body to cause the body to move
object from space that survives impact with Earth's surface
objects in space that range in size from sand to large boulder; does not have a tail
Near Earth Objects (NEOs)
any Solar System object in an orbit that passes close to Earth
a hypotetical comanion start or black hole to our Sun
A spherical region of comets that surrounds the solar system
Raup, D. and Sepkoski, J.
two scientists who proposed that extinctions occur periodically, every 26-30 million years
Red Dwarf Star
A very small star with low temperature, reddish in color.
a founder of planetary science; correctly deduced the nature of craters
large mirrors designed to be installed in space to move/steer space bodies using energy from light (photons)
the Sun and all the other celestial objects gravitationally bound to it
Space guard Survey
an international plan to survey all NEOs