Dinosaur Extinction Research

Dinosaur Extinction Research
Intro to question:
Their extinction occurred at the end of the Cretaceous period and is noted as one of the largest mass extinctions in Earth's history and is referred to as
the K–T (Cretaceous Tertiary) extinction but is now called the Cretaceous Paleogene (K–Pg) event by many researchers. So from this information a
question has been derived, How effectively does the asteroid theory explain the extinction of dinosaurs compared to other theories? A wide variety of
extinction theories have been suggested and some of the following examples have been evidentially thought wrong by many. Some examples of the
extinction theories are the toxic volcanic gasses and dust (Volcanism), asteroid impact onearth and climate change. Some scientists have suggested ...
Show more content on Helpwriting.net ...
In the early to mid stages of the Cretaceous period the worlds temperatures became hotter by about 10В°, some scientists have linked this to the
Asteroid Impact theory. Others linked it to the volcanic activity that is known today as India and Pakistan. The late Cretaceous period was a great
time of change, continents were splitting and volcanoes were spitting lots of gas and ash into the atmosphere greatly altering climate. Whether it be
gradual or sudden changes in climate dinosaurs habitats and environment would have been affected making it harder for them to adapt. A sudden
change may have triggered a change in the weather thus affecting food sources. Gradual changes may have slowly changed environments like cool
wet areas into dry areas affecting life there in a big way.
Prove theories?/evidence: –300
A team led by the Nobel Laureate Luis Alvarez demonstrated that a large bolide (generic term for meteor, comet or asteroid) had collided with Earth
close to or at the end of the Cretaceous extinction event roughly 65 million years ago. Evidence for this is the concentration of a rare Earth element
Iridium in the sediments of areas in Italy. Iridium is rare as it is most commonly found on bolides that have come in contact with Earth as opposed to in
the Earth.
Answer/full conclusion:
... Get more on HelpWriting.net ...

Dinosaurs And The Past ( Triassic Period )
Dinosaurs were huge animals that existed in the past (Triassic period). Species came in different sizes and forms. Some had huge bodies while other
tiny bodies and shape. From historical evidence prevalent today, dinosaurs were found in all continents but differed in sizes and physical attributes. The
landmass prevalent in different regions denoted the type of species that existed within its boundaries. Some Dinosaurs were herbivores; therefore their
teeth and digestive systems were developed to handle the plants they consumed. The planet at the time was covered with green plantations that the
animals fed on. Their sprawling posture that Dinosaurs possessed depicted their ability to eat leaves on high branches and twigs. Other Dinosaurs
survived on meat from other animals. A famous example includes Tyrannosaurus Rex (Kays and Wilson). The animal jaws and muscles were very
strong with pointed teeth. This enhanced its hunting skills as well as helped with feeding. During this period there were a lot of herbivores roaming the
earth (Johnson). Africa, Asia and Europe were the major continents. Through splitting, other continents were formed. Water bodies, such as the
Mediterranean Sea that is found between Europe and Africa, separated these regions. Thus, dinosaurs were distributed sparingly within these
continents. There were many different species of dinosaurs, such as Megalosaurus, Herrerasaurus, and Tyrannosaurus rex. Evidence of existence and

Eras
There are many theories about how earth came to be, and one of them a scientifically detailed explanation. In this theory, it is said that earth's history
has been broken up into four main eras. The Precambrian, Paleozoic, Mesozoic, and Cenozoic Eras. Each of these eras have there own
accomplishments, or milestone events, that occurred within the time period. From one–celled organisms to dinosaurs, it all eventually leads up to the
first sightings of humans. The first era to occur was the Precambrian Era. One of the first events to happen in the history of the earth is the Hadean
Eon. The Hadean Eon was the time period in which earth's surface hardened and became solid. Scientists found out the location of the layer that the
Hadean Eon occurred... Show more content on Helpwriting.net ...
One of the Cenozoic Era's milestones is development of mammals. Mammals ruled the Cenozoic Era after being some of the only surviving species
after the mass extinction of the dinosaurs. Fossils of mammals can be found using radioactive dating to show when these mammals dominated the
Cenozoic Era. And the last event to talk about is the placement of some of the continents and land masses. India collided with Asia between 55 and 45
million years ago, and Arabia collided with Eurasia 35 million years ago. Scientists can date these events by taking the direction that the plates are
moving and "reversing" the

Asteroid Theory
In the early nineteen hundreds, dinosaur fossils were discovered and recognized around the globe. Scientists and paleontologists began contemplating
how such densely populated creatures vanished. Currently, paleontologists debate the two main hypotheses of how the dinosaurs died from either the
volcano activity or the asteroid impact. Both theories resulted in the same outcome yet differ in key elements such as, the physical evidence left behind
encourages every conceivable clarification for the termination in charge of wiping out the dinosaurs.
As a matter of fact the theory that has gained wide acceptance today is that an asteroid collided with Earth. A large meteor–like ball striking the Earth
ejecting enough debris and dust that it resulted sunlight blockage long enough to modify the atmospheres climate, executing a comparability of the
"nuclear winter." These events occurred in a sort of domino effect, plants were the first to die out, followed by the herbivores that ate them, and
finally the carnivores that fed on the herbivores. Walter and Luis Alvarez from the University of California at Berkeley proposed the main hypothesis
in 1980. Team Alvarez firmly believed that the iridium layer is to blame an asteroid... Show more content on Helpwriting.net ...
For instance, the "150–kilometer–wide crater lies just off the Yucatan peninsula. Paleontologist calculated that is was blasted into earth by a
10–Kilometer–wide asteroid at a speed of 30 kilometers per second" 2. Scientists have concluded that the impact that created this crater occurred 65
million years ago. The date corresponds perfectly to the date of the dinosaur extinction. These pieces of molten rock, known as impact ejecta, were
found more than a hundred miles from its genesis Cretaceous boundary; this demonstrates that the explosion was intense enough to melt the surface
layer, proclaiming the extinction of

The Cretaceous Er The Last And Longest Segment Of The...
According to a live science, an article written by Mary Bagley, "The Cretaceous Period was the last and longest segment of the Mesozoic Era. It lasted
approximately 79 million years, from the minor extinction event that closed the Jurassic Period about 145.5 million years ago to the
Cretaceous–Paleogene extinction event dated at 65.5 million years ago"(Mary Bagley, LS). In the cretaceous period, the continent of Pangea was still
breaking away from itself, forming what we now know as the seven world continents. In the many eras of dinosaurs, the cretaceous era was
responsible for evolving some, but not all the dinosaurs from full land dinosaurs to some who were able to live both on land and in water,
semi–aquatic carnivorous dinosaurs. This era had produced some of the dinosaurs that maybe us non– paleontologist are more familiar with like the all
mighty tyrannosaurus rex or the long neck. Well let me tell you, there were a lot more dinosaurs than just those two. Although the tyrannosaurs rex was
an enormous dinosaur, a bigger dinosaur was discovered in 1912, the Spinosaurus. This discovery would change peoples, kids, and paleontologists
view on which dinosaur was bigger than the other. This semi–aquatic dinosaur, Spinosaurus, was much larger than the T–rex due to its sail like
backbones that stuck out of its back. Furthermore, spinosaurus had a huge advantage that the tyrannosaurus–rex did not.
A Paleontologists job is to study their dinosaur discovery, and to tell us

Kreidezeitudist Movement Essay
The fifth, and one of the largest and most well known extinctions in Earths history was the Cretaceous period, where many species, including the
dinosaurs, pterosaurs, and large marine reptiles, disappeared. This period was widely known as the K–T period, K being the traditional abbreviation
for the Cretaceous Period derived from the German name Kreidezeit, and T being the abbreviation for the Tertiary Period (a historical term for the
period of time now covered by the Paleogene and Neogene periods). It was a relatively warm climate and had high global sea levels. The oceans and
seas were populated with now extinct marine reptiles, ammonites and rudists, and the land by dinosaurs. At the same time, new groups of mammals
and birds as well as flowering plants appeared. The early part of the Cretaceous showed a cooling trend that had been ... Show more content on
Helpwriting.net ...
Because there were no known fossil non–avian dinosaur fossils in rocks younger than the K–T boundary, scientists have concluded that non–avian
dinosaurs became extinct immediately before, or during the event. It is possible that small dinosaurs (other than birds) did survive, but they would
have been deprived of food as both herbivorous dinosaurs would have found plant material scarce, and carnivores would have quickly found prey to be
in short supply. Ectothermic (cold–blooded) crocodiles have very limited needs for food (they can survive several months without eating) while
endothermic (warm–blooded) animals of similar size need much more food in order to sustain their faster metabolism. Therefore, under the
circumstances of food chain disruption previously mentioned, non–avian dinosaurs died while some crocodiles survived. The survival of other
endothermic animals, such as some birds and mammals, could be due, among other reasons, to their smaller needs for food, related to their small size
at the extinction

Tertiary Extinction Essay
In this day and age, many humans learn about dinosaurs through scholarly journals, academic settings, or by viewing skeletal remains or reproductions
by visiting museums. We know dinosaurs existed by the artifacts scientists uncovered over the years. However, varying conclusions from data and
research compiled from experts still differ in their determinations as to the demise of these noble creatures. In the article, of Extraterrestrial Cause for
the Cretaceous–Tertiary Extinction, researchers combine efforts to prove an asteroid spanning six miles collided with earth and destroyed the dinosaur
population (Alvarez et al. 1980). Many theories exist regarding the existence and extinction of the dinosaur species. However, this essay will ... Show
more content on Helpwriting.net ...
Collaborating with experts from other disciplines further strengthened their hypothesis. Extracting samples and analyzing the structure compared to
findings of the extraterrestrial substance, helped create a compelling reason for the reader to consider the notion of an asteroid colliding with Earth
being the cause for the extinction of dinosaurs. The scientists supported their theory by data from an interdisciplinary approach instead of focusing on
one particular scientific area to aid in convincing other professionals in their

Essay about Examining the Cretaceous: Paleogene Extinction...
Examining the Cretaceous–Paleogene extinction event Over 98% of all organisms that have lived on Earth are now extinct. A mass extinction event
occurs when a large number of species die out within a small time frame (relative to the age of Earth). Mass extinctions are intensively studied for both
cause and effect, as there is usually room for debate regarding catalysts that precede the extinction and the massive influx of new biological species
that follows. There have been five major mass extinctions, dubbed the "Big Five," that have wiped out at least 50% of the species living at those
times. The most well known mass extinction of the Big Five, with the decimation of every species of non–avian dinosaur, is the Cretaceous–Paleogene
... Show more content on Helpwriting.net ...
This final blow would have sent earth into a nuclear winter. According to this theory, dust caused by the asteroid collision disrupted plant growth by
blocking out the sunlight needed for photosynthesis for nearly a year. A chain reaction occurred as plants died off, so did the herbivores relying on the
plants, and then the carnivores that relied on the herbivores. Around 75% of species became extinct, including dinosaurs, mammals, giant marine
lizards, fish, birds, and insects. Meanwhile, seawater flooded around 40% of the world's continents ("Mass Extinctions").
However, such mass extinction opens up speciation – when new species are developed. After the K–Pg extinction, new groups of organisms were on
the rise. Giant boid snakes (12 – 15 meters) began appearing on land and the teleost fish (diverse class of ray–finned fish) filled marine niches left
vacant. Most significantly, "Paleocene mammals would spread and evolve into the many ecological niches left open by the extinction of the dinosaurs,"
("Cretaceous: Extinction of the Dinosaurs"). The entirety of Earth's ecosystem was affected by the K–Pg extinction, caused by volcanoes, oceanic
shifts, and ultimately, an asteroid. Lucky for humans, mammals capitalized on the opportunity

The First Period In The Phanerozoic Eon
The Paleozoic Era was the first in the Phanerozoic Eon. In the Paleozoic Era all life lived in or around water. This is because land was not
sustainable for life yet.The Paleozoic Era had six different periods. The Era lasted about 542 million years but ended because of the Cambrian
explosion. The first period in the Paleozoic Era was the Cambrian Period. The Cambrian Period was an important part of Earth's history and formation.
It was when mainly all of life first came around. The second period in the Phanerozoic Era was the Ordovician Period. During the Ordovician Period
most of the land of Earth was mainly in the supercontinent Gondwana.
Thirdly, came the Silurian Period. In the Silurian Period glaciers started to melt. Next came the ... Show more content on Helpwriting.net ...
The Mesozoic Era was when dinosaurs roamed the Earth. During the Mesozoic Era was when life started to live on the land. There were three
periods during the Mesozoic Era. The Mesozoic Era last for about 180 million years.
The first period in the Mesozoic Era was the Triassic Period which was the very first time life started to form on Earth. The Earth was in the form of
the supercontinent Pangea. During the Triassic Period Pangea broke apart into two pieces and formed the continents Laurasia and Gondwana. The
Triassic Period ended about 199 million years ago. Next was the Jurassic Period which was the period when the Earth went through a major climate
change, making it mostly tropical and humid. This was the period in which Dilophosaurus ruled above all dinosaurs. It ended about 200– 145 million
years ago.
The last period on this Era was the Cretaceous Period. This period was the longest period in the Mesozoic Era. During this Period the seasons started.
The poles got colder. It was also during this period that the tropical areas were restricted to the equator. Some of the animals in this period were,
Iguanodons, hadrosaurs, and the Tyrannosaurus

Cretaceous-Triassic Extinction Research Paper
An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the amount of life on Earth. It occurs when
the rate of extinction increases with respect to the rate of speciation. Extinction occurs at an uneven rate.
The most recent and debatably best–known, the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago (Ma), was
a large–scale mass extinction of animal and plant species in a geologically short period of time.
It is now generally believed that the K–Pg extinction was triggered by a massive comet or asteroid impact 66 million years ago and its catastrophic
effects on the global environment, including a lingering impact winter that made it impossible for plants and plankton to carry out photosynthesis. The
fact ... Show more content on Helpwriting.net ...
The sea floor is also completely recycled every 200 million years by the on–going process of plate tectonics and seafloor spreading, leaving no useful
indications beneath the ocean. The former group includes one or more large bolide impact events, increased volcanism, and sudden release of methane
from the sea floor, either due to dissociation of methane hydrate deposits or metabolism of organic carbon deposits by methanogenic microbes. The
latter group includes sea level change, increasing anoxia, and increasing aridity. Any hypothesis about the cause must explain the selectivity of the
event, which affected organisms with calcium carbonate skeletons most severely; the long period (4 to 6 million years) before recovery started, and the
minimal extent of biological mineralization (despite inorganic carbonates being deposited) once the recovery

Outline Of The Dinosaur Extinction
Outline
The Dinosaur Extinction:
Introduction to the K–T event.
Theories of extinction.
Assumptions of extinction:
1.Due to climate change.
2.Due to small mammals that ate dinosaur eggs.
3.Due to dinosaurs' bodies that are too big to be worked by their little brains.
4.Due to starvation.
5.Due to environmental change.
6.Due to Supernova that showered the earth in radiation.
7.Due to iridium–enriched mud.
Extinction– Still a theory.
The K–T event, or the Cretaceous–Tertiary extinction event, is the name given for the vanishing of the dinosaurs and different species that took place
about 65 million year back. For ages, scientists believed that this event was caused due to the atmospheric and topographical changes that invaded on
the dinosaurs' food supply. But, in the 1980s, researchers Luis and Walter Alvarez discovered a layer of iridium on the earth's surface. It suggests that a
comet, space rock or meteor effect might have caused the extinction of the dinosaurs. In the 1990s, researchers found the enormous Chicxulub Crater at
the tip of Mexico's Yucantan Peninsula, which dates to the period being referred [1].
There are various theories, yet no proofs. Dinosaurs wandered the earth for about 160 million years until their sudden eradication approximately 65
million years prior, in a K–T extinction event. Other than dinosaurs, numerous different types' animals and plants ceased to

Dinosaurs: The Possible Causes Of Mass Extinction
Why dinosaurs disappeared?
Sixty six million years ago the Dinosaurs died out with no clear explanation. There are many different theories to why the Dinosaurs became extinct .
The possIble Causes of the mass extinction vairy widely. Some of those theories were the Asteroid theory, climate change andvolcano theory. The
theorys that are most clear to why the dinosaurs died out with the Most evidence is the volcano and asteroid theory , the theorys involved an asteroid
hitting into earths surface causing a massive volcano exploding in India, which lasted a long time and let loose gases into the atmosphere, causeing the
climate to rapidly change killing the dinosaurs over time. There was a lack of sunlight caused by the dust layer, ending

Taking a Look at the Tertiary Period
"The Tertiary Period began 65 million years ago and ended just 1.8 million years ago. It was made up of 5 different epochs." "Paleocene epoch that
was 65 to 54 million years ago." " Eocene epoch that was 54 to 38 million years ago." " Oligocene epoch 38 to 24 million years ago." " Miocene epoch
24 to 5 million years ago." "Pliocene epoch 5 to 1.8 million years ago."
Tertiary is the third era. "During the Tertiary period placement of the continents were different than were they are located today." "There were only
the Pacific Ocean, Atlantic Ocean, and the Indian Ocean." " Continents were North America, Greenland, northern Europe, Asia, and Iberia." Climate
change from the beginning to end was very significant. "During the beginning the earth was warm and moist compared to the weather now." By the
middle of the period earth started to cool. This was cause by volcanoes that kept giving off carbon dioxide." After a while by the end of this period it
was so cold that the last ice age had started." "However this had to be the most important time period for mammals." "The time period before Tertiary
which was the Cretaceous period." "The Cretaceous period ended with the extinction of dinosaurs, large reptiles, and many different others." "After all
the extinction of the other animals mammals became the dominant species on Earth." "This is why the Tertiary Period is called the age of mammals."
"There are to unusual mammals that we have researched on from this period that were

Beach Marine Sediments
Marine Sediments are the particles of organic or inorganic matter that accumulates in a loose, unconsolidated form. After the continuous raining of
sediments, the deep floors have varied from centimeters of thickness per year. When we think of sediment, we think have erosion of minerals that were
once on land, remains of living organisms, and chemical reactions that associate with the ocean (terrigenous,biogenic, hydrogenous, and cosmogenic ).
This process has helped determine the age of the seafloor and what it may be in the future. Sediments are like the memory of the ocean, due to the
recycled tectonic plates, only dates back to 180 million years ago. Although the ocean cannot reveal its early history, sufficient evidence has allowed...
For example, one could find this sand on our near by beaches such as Newport. There are other sand types such as coral sand, where could
primarily be found in the shore of Oahu, Hawaii. White sandy beaches could also consist of limestone and other types of coral as well. Now in
reference to how each of these kinds of beaches does not have the same sand type, is due to the fact that areas are geologically different. Newport
beach is located on the edge of the pacific plate, right along the North American, where we find all types of terrain and activity. We can assume that
we have an average amount of rainfall, wild fires here and there, and all types of natural sediment that find its way to the ocean. When we compare
this to the island of Hawaii, we find that its approximately located in the middle of the pacific, has more of tropical type weather and has lots of
volcanoes. Now each area of the world varies and ultimately this decides what kind of water temp there will be, what kind of terrain and what types
of sea life it will harbor. This is how many beaches around are different Its not because of the formation of which the ocean was made or how

The Common Pattern Of Alternating Extinctions And Radiations
Extinctions and Radiations
W 1, A 3
Bio 1021
By
Roxanne Fortune
South University
Submitted: November, 16th, 2016
The common pattern of alternating extinctions and radiations has been done through biodiversity studies which studies the different organisms of
species living on earth and where they live. In Stilwell (2003) journal, "Palaeocene faunas are characterized by a perceived rapid evolutionary
radiation involving many new taxa at both genus and species level." Stilwell stated Molluscs living at the beginning of tertiary period after the K–T
extinction event was the beginning of modern fauna. There was research that saw the decimation of scores of marine organisms. "Mollusc groups were
mentioned (e.g. Ammonites, Belemnites' Rudistid and Trigoniid Bivalves)," (Stilwell, 2003).
In Stilwell's research journal, Austral Palaeocene Molluscs focuses on the composition of faunas and patterns of evolution, it shows diversity and
riches. The Southern Hemisphere show the break– up of Supercontinent Gondwana and also changes in oceanic circulation and climate. In the northern
Hemisphere shows major diversity changes in the Marine Realm.
In a journal written by Racki, it was mentioned, "with the enlargement and nitrification most likely will lead to the loss of deep water niches and step
by step siliceous faunas go through severe non–selective losses during the end–Permian mass extinction," (Racki, 1999). All because of sudden
volcanic winter the super anoxia

Extinction of Dinosaurs due to Asteroid Impact Essay
Extinction of Dinosaurs due to Asteroid Impact
Nobody knows for sure exactly how the dinosaurs became extinct. However scientists have speculated for decades about possible events that caused
the dinosaurs to die out. Possibilities range from asteroids, to volcanoes, to climate changes. One of the more popular or well–known extinction theories
involves the belief that an asteroid struck the Earth, causing devastating effects, and triggering mass extinctions around the end of the Cretaceous period.
The asteroid impact extinction theory began in 1980 with Luis and Walter Alvarez, a father and son team. They theorized that an asteroid struck the
Earth at the close of the Cretaceous period, causing devastating effects and mass ... Show more content on Helpwriting.net ...
Gerta Keller, professor of geosciences at Princeton University, has recently conducted research on the Chicxulub asteroid in which she analyzed new
core samples taken from the asteroid site (Botzer 2004). These samples indicate that the impact that occurred at Chicxulub actually predated the mass
extinction of the dinosaurs, which occurred at the Cretaceous–Tertiary boundary about sixty–five million years ago. Keller claims that the Chicxulub
impact occurred approximately 300,000 years before the extinction (Keller 2004). Although previous researchers estimated that the Chicxulub asteroid
was the cause of the extinctions, there had always been doubts about the exact age and size of the crater, and about the origin of the "mega tsunami
deposits" that were located within the crater (Keller 2004). The focus of Keller's recent research was on finding some answers to these questions. To
do so she analyzed Cretaceous limestone, dolomite, and anhydrite deposits as the site of the Chicxulub crater (Keller 2004).
The fossil deposits at the Chicxulub site suggest that the mineral layer in the crater was deposited after the impact, but before the extinction of the
dinosaurs and other species. Keller proposes two possible explanations for this. The first explanation is that the sediments were deposited as the
backwash of a giant tsunami that occurred after the impact (Keller 2004).

Ordovician-Silurian Extinction
Approximately 66 million years ago, the first, and most recent extinction event of 'the Big Five' took place– the Cretaceous–Paleogene (K–Pg)
Extinction, also known as the Cretaceous–Tertiary (K–T) Extinction. While this event is known primarily for its involvement in the extinction of
dinosaurs, it also had quite the effect on a large majority of other plant and animal species, to the point where no tetrapod (four–legged vertebrae)
weighing above 25 kilograms survived. The original trigger is believed to have been a massive comet or an asteroid impact, estimated at about ten
kilometers in size, but other theories suggest that volcanic eruptions, climate change, or sea level change played a role was well. Either way, there were
catastrophic... Show more content on Helpwriting.net ...
However, recent speculation has lead many scientists to believe that we are currently in a mass extinction period, one that could not only be bigger
than any previous extinction event, but that actually points a finger towards humans as being the main cause. This extinction event is known as The
Holocene Extinction, the Sixth Extinction or the Anthropocene Extinction, and whether we like it or not, there is definitely a considerable amount of
evidence to prove that this mass extinction is happening, and that the cause is largely due to human activity. Specific research indicates that
deforestation, hunting, pollution, the introduction of non–native species into various regions, destruction of vast tracts of land, river systems, and
habitats, and the widespread transmission of infectious diseases spread through livestock and crops are having the most drastic effects on most
species. Current studies even show that the present rate of extinction may be up to 140,000 species per year, making it the greatest loss of biodiversity
since the Cretaceous–Paleogene Extinction. Edward Osborne Wilson, an American biologist, researcher, theorist, naturalist and author, calculated that
if the current rate of human disruption of the biosphere continues, one–half of

Word Bank Quiz
Word Bank: A. Fossil, B. Paleontologist, C. Mold, D. Cast, E. Law of Superposition, F. Petrified Fossil, G. Trace Fossil, H. Scientific Theory, I.
Scientific Fact, J. Radioactive Dating, K. Absolute age, L. Extinct, M. Relative Age, N. Unconformity, O. Index Fossil, P. Era, Q. Half Life, R.
Geologic Time Scale, S. Period, T. Epoch, U. Mass Extinction, V. Reptile, W. Pangaea, X. Amphibians, Y. Eon _______1. A type of fossil that
forms when sediments fill in the cavity left by a decomposed organism. _______2. Statement or data that can be proven. _______3. Number of years
when the rocked formed _______4. The death of every member of a species. _______5. Animal where skin maintains fluid, and embryos live inside a
shell. _______6. Trace of animals that lived long ago, mostly commonly preserved in sedimentary rock.... Show more content on Helpwriting.net ...
Surface where new rock layers meet a much older surface. _______8. In horizontal layers, the oldest rock is at the bottom, and youngest rock at
the top layers. _______9. Well tested concept that explains observations. _______10. Supercontinent formed 260 million years ago. _______11.
Scientist who study fossils. _______12. A fossil that is found in the rock layers of only one geologic age that is used to establish the age of the rock
layers. _______13. Provides evidence of activities of ancient organisms. _______14. A unit of geologic time that includes two or more
periods._______15. Minerals replace all or part of an organism. _______16. The time it takes for half of the radioactive atom to

Cretaceous-Rat Extinction Research Paper
The cretaceous–tertiary (KT) boundary extinction happened approximately sixty five million years ago. Sixty to eighty percent of all living species
became extinct at this boundary (Raup 1988). The KT extinction was indeed a mass extinction event. Mass extinctions are periods in Earth's history
when extremely large numbers of species die out simultaneously or within a limited time frame. The most severe mass extinction ever occurred at the
end of the Permian period when 96% of all species died out. The K–T mass extinction obliterated almost all the large vertebrates on Earth, on land, at
sea, and in the air (all dinosaurs, plesiosaurs, mosasaurs, and pterosaurs) suddenly became extinct at the end of the Cretaceous Period. At the same time,
most ... Show more content on Helpwriting.net ...
There are a lot of theories about why the K–T extinction occurred, but a widely accepted theory was proposed in 1980 by a physicist named Luis
Alvarez and his son Walter Alvarez who was a geologist. the theory is that an asteroid 4–9 miles (6–15 km) in diameter hit the Earth about 65 million
years ago, creating the Chicxulub crater at the tip of Mexico's YucatГЎn Peninsula. The crater is more than 110 miles in diameter and 12 miles in
depth. It is one of the largest confirmed impact structures on Earth; The impact would have penetrated the Earth's crust, scattering dust and debris into
the atmosphere, and causing huge fires, tsunamis, severe storms with highly acidic rain , seismic activity, and perhaps even volcanic activity . The
impact could have caused chemical changes in the Earth's atmosphere, increasing concentrations of sulfuric acid, nitric acid, and fluoride compounds.
The heat from the impact's blast wave would have incinerated all the life forms in its path. The evidence for the impact was first discovered by Walter
Alvarez and some of his colleagues. They found that rocks laid down precisely at the K–T boundary contain extraordinary amounts of the metal
iridium. The dating is precise, and the iridium layer has been identified in more than one hundred places around the Earth. Where the boundary is in
marine sediments, the iridium occurs in a layer just above the last Cretaceous microfossils, and the sediments above it contain Paleocene microfossils
from the earliest part of the Cenozoic. Iridium is much rarer than gold on Earth, yet in the K–T boundary clay iridium is usually twice as abundant as
gold, sometimes more than that. The same high ratio is found in meteorites. The Alvarez group therefore suggested that iridium was scattered
worldwide from a cloud of debris that formed as an asteroid struck somewhere on Earth. Shocked quartz was

Causes Of Mass Extinction
Throughout the history of earth there have been five mass extinction events that have wiped out most life on earth. To go into detail the first mass
extinction event happened over 439 million years ago due to glaciation and falling sea levels were around 86% of the life on earth was wiped out.
The second happened around 364 million years ago killing around 75% of species. Giant plants were presumed responsible for this event because of
their deep roots that released nutrients into the ocean which, resulted in mass amounts of algal bloom that depleted the seas of oxygen. The worst mass
extinction occurred 251 million years ago, during the Permian – Triassic period that wiped out around 96% of species. A gigantic volcanic eruption
filled the air with carbon dioxide which fed different kinds of bacteria that began emitting large amounts of methane. As a result theearth warmed up
and the oceans became acidic. Afterwards the Triassic– Jurassic extinction happened between 199 million and 214 million years ago. The cause of this
extinction is thought to be an asteroid impact, climate change, and flood basalt eruptions. During this period dinosaurs came the rule over most of the
earth. Finally, the Cretaceous – Paleogene extinction happened around 65 million years ago. A combination of volcanic activity, climate change, and
asteroid impact effectively ended 76% of life on earth including the dinosaurs. And through these mass extinctions there has been few who have lived
through

Permian and Cretaceous Mass Extinctions Essay
Assess the different hypotheses put forward for the mass extinctions at the end of the Permian and Cretaceous (KT) Periods.
A mass extinction is an event in which at least 25–75% of species in the global environment are eradicated in a short period of time. Where as a
regional extinction event is when the extinction is confined to a specific zone. Five mass extinctions have occurred throughout time, two of the most
well known of these are the Permian and Cretaceous extinction events.
There are several hypotheses that are used to explain the causes of mass extinctions. Climate change, the warming or cooling of global environments
over a short period of time, can lead to other occurrences. Shifts in climate can cause extinction by ... Show more content on Helpwriting.net ...
A crater, the Bedout crater, in Australia has been discovered. A bolide impact would have lead to mass death of marine and terrestrial organisms. The
force of the impact could have released methane from stored organic matter and large earthquakes. These earthquakes would have triggered the
volcanism in the Siberian traps, leading to the release of large amounts of CO2 and sulfur dioxide. These gases combined with methane previously
released would have created a noxious atmosphere, combined with climate change that killed a large scale of life.
It is most likely that a simultaneous occurrence of the different global environmental changes was responsible for ending the Permian period, and the
lives of 96% of species. Each environmental issue is a major geological event, and amplified the other events, leading to catastrophic environmental
situation, in which barely any life could survive.
The Cretaceous – Tertiary mass extinction, commonly referred to as the KT extinction, occurred 65 million years ago. As the most recantextinction
event it is more easily studied as more evidence has been preserved than for the earlier extinctions. This extinction is the most commonly known, as it is
the extinction of the dinosaurs, but the smallest scale mass extinction with only 76% of species dying out.
Evidence for catastrophism at the KT boundary can be found in a layer of greenish

The Cretaceous-Tertiary Extinction
The Cretaceous–Tertiary extinction or K–T extinction, which marks the Late Cretaceous, is a massive and large–scale extinction of animal and plant
species that occurred over a short period of time 66 million years ago. The fossils of non–avian dinosaurs (the Group of birds) found almost only below
the K–T boundary, paleontologists mostly estimate that the dinosaurs were extinguished just before, or during the event. Scientific theories explain the
extinctions of K–T by one or more catastrophic events, such as massive asteroid impacts, and increased volcanic activity, however, the volcanic
activity appearing to be anterior. The dating of several impact craters and that of rocks resulting from massive volcanic activity in the Deccan traps
coincide

Majestic Dinosaurs
The title of the article I chose is Paleontologists probe the majestic reptiles' origin and rise writen by Alenxandra Witze. This article talks about
paleontologists excavating ancient fossils, giving them more information about the common ancestor of dinosaurs, and how they came to rule the
earth for millions of years. The author gives us an example of what the ancestor of dinosaurs may have looked like, by telling us that it "probably
looked something like a chicken". Just as there was a mass extinction that wiped out most dinosaurs, there was a mass extinction millions years before,
that gave the dinosaurs an opportunity to rise and evolve. 252 millions years ago, between the Permian and Triassic periods a mass extinction wiped
out most life on Earth. This gave the opportunity for new groups to ... Show more content on Helpwriting.net ...
The oldest piece of evidence showing that the first dinosaurs showed up during the Triassic time period, are the fossil footprints found that date back
250 million years, although not everyone is convinced that the footprints are definite evidence. Scientists are not sure how to classify some of the
earliest species found between the three main branches of the dinosaur family tree: Theropods( two–legged meat eaters),
Sauropodomorphs(four–legged, long neck plant eaters), and Ornithiscians ( "bird hipped" dinosaurs). Although these fossils help paleontologists
discover new information, new findings also come from close relatives of dinosaurs, just like "a long talk with an estranged cousin can help fill in
family history, these discoveries are illuminating how dinosaurs evolved alongside other animals". One of the relatives that helped with this process are
the silesaurids. Their bones help illuminate crucial differences between dinosaurs and their relatives deep in the

Alvarez Hypothesis
The Alvarez hypothesis is the most popular hypothesis, there is to be for the extinction of the dinosaurs. This is due to the fact that this theory has lots
of scientific proof to support its theory.
There is a crater that is approximately 150 kilometers in width. Experts have analyzed this crater and have come to a conclusion that an asteroid that
had a width of 10 kilometers crashed at Chicxulub on the Yucatan Peninsula in Mexico around about 65 million years ago (this around the same time
the dinosaurs went extinct. (Pilkington, 2001)
If the asteroid had hit, most of the cretaceous plants would have been destroyed thus the dinosaurs at the bottom of the food chain would soon have
died due to lack of food. This led to the dinosaurs at ... Show more content on Helpwriting.net ...
Experts have found extra iridium (an element) in the soil– asteroids are commonly known to have extra iridium. The theory is that once the asteroid hit
the surface of the earth fragments of the asteroid were spread around. (Pilkington, 2001)
Experts have found fractured crystals also known as 'shocked quartz' between the soil layer that was close to the time of the extinction of the dinosaurs.
These crystals have arrangement in them which can only be made by great collisions or eruptions. (Pilkington, 2001)
The soil layer from the time of the extinction of the dinosaurs has been analyzed by experts and they have found a lot of ash. This is another sign that,
after the asteroid hit the Earth, there was a massive fire that took out most of the plants and trees on Earth. (Hartmann, n.d)
Experts have calculated that an asteroid of the size that hit the Earth 65 million years can hit the Earth approximately every 100 million years.
(Hartmann, n.d)
There are theories that remains of the asteroid caused a storm filled with fireballs in the sky, which led to temperatures increasing. In some places the
temperature reached boiling point which would have kill quite a few animals and plants. There are also theories that the high temperatures could have
started enormous

Endothermia Condition In Dinosaurs
The reading passage discusses an interesting topic about the possibility of the endothermia condition in dinosaurs and provides three reasons for
support. However, the lecture cast doubts on the claim made by the article and opposes each of the reasons of the reading passage. First, the reading
passage sustains the idea of endothermic dinosaurs on the fossils discovered in Polar Regions, meaning that only this type of animals could survived
in such low temperatures. On the contrary, the lecture refutes this idea by arguing that the area where the fossils were discovered was warmer back in
those days when dinosaurs were alive. Moreover, as many reptiles today that live in areas with cold winters, the dinosaurs could migrate or hibernate
escaping

Permian Extinction
Over the course of its 4.5–billion–year history, the Earth has seen the rise and fall of many populations of organisms. However, in Earth's history,
there have been five big mass extinction events, characterized as "periods in Earth's history when abnormally large numbers of species die out
simultaneously or within a limited time frame." (BBC) These events are cataclysmic enough to wipeout at least 50% of all organisms living during that
period. The causes of mass extinction are many from the asteroids that sealed the fate of the dinosaurs to the volcanoes that choked out air to 96% of
the organismic population during the Permian extinction, however one of the most recent yet potent mechanisms of bringing upon a mass extinction
are humans. ... Show more content on Helpwriting.net ...
In the span of 50 years, the population of humans on this planet have reached all–time highs and continue to rise and with this rise comes the effects of
overpopulation. The planet cannot sustain so many people during such a short span of time. Not only is there a loss of space for new generations
of humans to live on, but there has been an excessive use of natural resources before there is a chance to replenish them such as food, natural gases,
and water. The problem of overpopulation seems to truly encompasses all other aspects of the factors leading to the sixth mass extinction such as
habitat loss and global warming. The population must be feed and because of this, million upon millions of acres of land once inhabited by a
whole ecosystem have been converted to farmland to provide food for the growing population. In addition, the increase in leads to an increase in
waste and therein arises a problem: where to put the waste. In the United States alone, "4.39 pounds of trash per day and up to 56 tons of trash per
year are created by the average person" Landfills seemed to be the perfect solution for this problem, however, over the years, "landfill managers have
been emphasizing just how quickly they are running out of space. The more people there are on the planet, the more waste is being produced. Some of
this waste is quite toxic, and even landfills which are

Tyrannosaurus Rex Research Paper
There are different kinds of dinosaurs around the earth. Dinosaurs are in museums and in the ground, there are probably more about dinosaurs to be
discovered. For my research I will be finding things and information about the Tyrannosaurus Rex (T–Rex). The average Tyrannosaurus Rex lived from
20–30 years. The Tyrannosaurs Rex was up to 40 feet long, and 15 to 20 feet tall. The Tyrannosaurus Rex weighted about 7 tons. Some scientists think
that they eat up to 500 pounds of meat. The skull was 5 feet, the largest tooth for the T–Rex is 12 inches. The Tyrannosaurus jaw was 3.9 feet wide for
eating his prey whole. The dinosaurs died about sixty–five million years ago. There has been many theories about how the dinosaurs became extinct.
Some of

Three Major Theories Explaining The Extinction Of The...
The Three Major Theories Explaining the Extinction of the
Dinosaurs
There are many theories explaining the extinction of the dinosaur. The Most probable theories are: a massive meteor hit the earth causing the
extinction. B. A chain of volcano's erupted and caused acid rain, shortage of sunlight and any other number of atmospheric problems that brought about
the extinction of dinosaurs. C. Rapid Climate Change in a short period of time would have brought the dinosaurs to extinction because of an inability
to evolve to the new environment. All these theories are possible but it is clear that it was a combination of all three theories working together that
produced a worldwide extinction event.
Around 65 million years ago; there was barely ... Show more content on Helpwriting.net ...
But there's more new studies say that there could have been more then one impact that was left undiscovered because of continental drifting
So as the planet cools the cloud of ash dissolving in the years to come what is left of the dinosaurs? Well almost all natural drinkable waters are
polluted leaving no water for the dinosaurs, even the rainwater is made of poison acid and dust so if they find a watering hole inside a cave or water
seeping out of the ground the area is most likely to be a trap the air around it could be poisoned with hydrogen sulfide (it will stop your muscles from
working and ultimately suffocate

The Extinction Of Dinosaurs
Cribbins 1 Hook. The extinction of dinosaurs is a mystery in itself that has stumped scientists all over the world for decades, and they still look for new
answers every day. Scientists know some background information, but cannot connect the dots to see the bigger picture. There was little interest in the
topic until Luis and Walter Alvarez proposed a groundbreaking hypothesis, which today we call the "Alvarez Hypothesis". This new idea of the
Alvarez's was exciting, and therefore got the media talking about it, which in turn started the search of how the dinosaurs went extinct. Another popular
theory of how dinosaurs went extinct is the Volcanism Theory. Scientists have recently found new evidence supporting both sides of this debate.
Although many dinosaur extinction theories exist, only the Alvarez Hypothesis is correct. Scientists abase their extinction theories off one of
commonly known piece of information: that there was a change in climate around the time of the K–T boundary. Both major theories support this idea,
and both believe that something blocked out the Sun for many months. This stopped the photosynthesis in plants, the base of the food chain. Without
plants, the food chain was majorly affected. A domino effect happened, and one species died out after another. Eventually all species of dinosaurs died
out. Scientists know that there was a global climatic change, but are not sure how it happened. The topic of the K–T Extinction received little

K-T Extinction Outline
Dalia Rodriguez Historical Geology 205 November 25, 2015 KT Extinction
Abstract
The Cretaceous–Tertiary extinction, also known as the K–T extinction, was a global extinction event that struck the Yucatan Peninsula at the end of the
end of the Mesozoic Era, 65 million years ago. Walter Alvarez first discovered a meteorite big enough to be called a small asteroid that hit the Earth,
creating the Chicxulub crater. Once the asteroid struck the North American continent, there were igneous rocks underneath the crater that contained
high levels of a rare siderophile element, iridium. This catrostopic event had a massive effect on the environment, as several mammals, birds, and
plants became extinct. It also caused an impact winter that made it impossible for plants and plankton to photosynthesis, as 75% of inland animals
and 90% of marine species were affected. Not only did it cause an impact winter, but the asteroid also caused volcanic eruptions, climate change and
sea level rise. Geologists have also found rich dinosaur, plant and marine fossils to illustrate the K–T extinction. This event not only caused species to
become extinct, but it also had an adaptive radiation, as other species were able to diversify.
Introduction
The asteroid colliding with Earth left evidence in the planets core and mantle with iridium and shocked quartz. Iridium is present in extraterrestrial
objects like asteroids and meteorites. The asteroid impact

Explaining Dinosaurs' Extintion
Though there is not one definitive explanation to explain dinosaurs' extinction, there are various theories that attempt to account for the mystery of
their extinction. The theories that explain their extinction at the end of the Cretaceous period are the asteroid, the volcanoes, and the major climatic
changes. The most popular theory for the extinction of the dinosaurs is that the Earth was hit by an asteroid or a comet. Was the impact actually the
cause behind the dinosaur's extinction? Or was it something completely different? An analysis of the evidence surrounding the extinction of dinosaur's
reveals that there are several different hypothesis that give theory on what might have happened.
Over 65 million years ago, planet Earth consisted of an extraordinary species known as dinosaurs. During this time something extremely large hit the
earth, causing global devastation. "65% of all life on the face of the planet was snuffed out of existence and the dinosaurs that roamed the planet up to
that point were no more" (O'Neill, 2009). Curiosity has grown over the past hundred years, and scientists and researchers have given their life to find
out what exactly happened on that mysterious day. "A dinosaur extinction hypothesis is a testable statement describing factors that may have
contributed to the dinosaurs' demise and how long the process may have taken. Evidence, observation, and experimentation can serve to support or
disprove a hypothesis. Regardless of its ultimate

Cause And Effect Of Chacxulub Impact
Chicxulub Impact
By Talullah Lennon
The Cause:
An Asteroid is formed in the inner solar system in a particular part called the Asteroid Belt, when small particles of rock and metal collide with each
other, and slowly build up over time. Planets are formed the same way as asteroids, but what stops asteroids from growing and becoming a planet is due
to the gravitationally pull of Jupiter. The asteroid belt lies between Jupiter and mars. Because of Jupiter's gravitationally pull the asteroid goes at a
highly increased speed causing it to crash into other asteroids in the belt, the result of this is either the asteroids bounce off one another or they break
off and don't stick together. The asteroid belt contains billions of asteroids in all different sixes. Majority are reasonable small around the size of a
large bolder but on occasion there are asteroids that are humongous just like the Chicxulub asteroid
When an asteroid hits Earth it normally strikes at the rapid speed of "16 to 32km/sec". The ... Show more content on Helpwriting.net ...
The asteroid instantaneously made a hole that was 100km wide and 30km deep. Experts say that " it hit at the same energy as 100 million atomic
bombs and left behind a 100–mile–wide scar known today as the Chicxulub creator" Many scientists believe that the impact of the Chicxulub asteroid
played a big part in the "KT Extinction" which was the extinction of almost all life on earth, including the dinosaurs. When the bowl collapsed it
left behind a 200km creator across and a couple of km deep. Later, on the centre of the crater "rebounder and collapsed again", this time it produced
an inner ring. Now days a larger percentage of the creator is buried offshore, under about 600m of sediments. The parts of the crater that are still on
land are cover in limestone and at the rim of the crater there is an arc of

Contrasting Theories on the Extinction of Dinosaurs Essay...
So what killed the dinosaurs? Without having any background education in science it is hard for the general public to comprehend such matters and
they rely on the knowledge of the scientists in this field. Although there has been much research on the subject nobody has come up with a conclusive
answer. And we are left to read the countless articles, all having their own opinions as to themass extinction. One such theory is that a shift in the solar
system could have caused the mass destruction. According to an article published in Nature magazine,
"A bizarre wobble 65 million years ago, perturbing the orbits of Mars, Earth and Mercury, may have caused the demise of the dinosaurs, new models
of the Solar System suggest."
The ... Show more content on Helpwriting.net ...
In this article other ideas are mentioned about what came after the meteorite hit,
"Some have proposed that this hot debris would have ignited vegetation wherever it fell to earth. Others believe a gigantic fireball, rising over
Chicxulub, would have spread hot material over the planet."
This researcher proposes that the dinosaurs did not die of heat, in fact she thinks the opposite, that they froze to death instead. Both articles have the
same idea about a meteorite hitting the earth yet there is no concrete evidence as to what caused the meteorite to strike and what it did when it got here.
Illustrated in an article, also featured in Nature magazine, is the competition between scientists to find any knowledge leading to an answer and their
differing views on the subject. Again the theory of debris blocking sunlight and stopping photosynthesis is brought up but it is apparent that it is only
one view in a sea of many.
"A minority disputes this theory, arguing that other events–such as volcanic eruptions, sea–level changes or a series of impacts–were to blame for the
spectacular loss of species that occurred at the transition between the Cretaceous and Tertiary periods..."
The article explains the consequences of their efforts to drill into the Chicxulub crater in Mexico, the site where the asteroid supposedly struck. There
was a lot of arguments as to which scientist would take the core section to analyze. In the end

Cretaceous Time Period Research Paper
Cretaceous Period
Everyone knows about the dinosaurs and how they went extinct. This was one of the major events that took place in the Cretaceous Time Period.
The Cretaceous Period was the longest and last of three time periods in the Mesozoic Era. This time period lasted from about 144 million years ago
until about million years ago (about 79 million years), and over that 79 million years the earth changed dramatically. Way back in theCretaceous all of
earth's land was together in one big super continent we call Pangea. The average temperature was warmer throughout earth then in comparison to
present day. The north and south poles were still colder than places along the equator even back then. But still, the earth was warmer than it is now
with excessive rains in some places and little to no rain in deserts. Maybe the most notable ... Show more content on Helpwriting.net ...
Approximately 65.5 million years ago most of the planet's land animals and many of the animals in the seas went extinct. As far as we know this was
caused by a massive asteroid colliding with earth in what is now the Chicxulub crater in the Yucatan peninsula. The collision is thought to have caused
tsunamis and clouds of hot dust were sent into the atmosphere and probably started huge wild fires. Many of the animals that survived all of that
would later die when the sun was blocked out for months or possibly years causing temperatures to drop and plants to die.
I would not like to have lived in the Cretaceous Period. For one thing pretty much all of the planet's land area was in a much hotter climate than we
live in which I don't think I would like. Another reason is the fact that the land and plants were different in a way that may have been interesting to
see but not so great to live in. And of course the obvious reason that there were still dinosaurs which would probably be pretty dangerous and make life

How Did the Dinosaurs Die and Will It Affect Humans in the...
Four and a half billion years ago, the debris and dust left from the formation of the sun coalesced to form our home planet. 3.5 billion years ago, the
first living organisms appeared on Earth. About 230 million years ago, Dinosaurs diverged from their Archosaurs ancestors during the middle to late
Triassic period. For 160 million years they have dominated our planet. They are dubbed the most successful species to have lived on Earth. However,
65 million years ago, the most recent mass extinction seemed to have caused all of them to die–off. What caused the demise of the dinosaurs and 60%
of life on Earth at the time? How did it affect life on Earth afterwards? Are all of the Dinosaurs dead? Will this happen to humans in the near future?...
None was found. Luis Alvarez was a Nobel Prize–winning physicist, inventor and pioneer in the field of radiation and nuclear research. He and his
son, noted geologist Walter Alvarez, were conducting research in Italy when they discovered a centimeter–thick layer of iridium–enriched clay at the
K–T boundary. Iridium is rare on earth, but more common in space. The Alvarezes published their findings in 1981, postulating that the thin layer of
iridium was deposited following the impact of a large meteor, comet or asteroid with the earth. Furthermore, this bolide impact (the meteor, comet or
asteroid colliding with the earth's surface) could have caused the extinction of the dinosaurs. At the time, the Alvarez theory was so farfetched from
prevailing hypotheses that it was derided. Slowly, other scientists began finding iridium evidence at various places around the globe that corroborated
the Alvarez theory. There was, however, no smoking gun in the form of an impact site. Then in 1991, a massive meteor crater 110 miles in diameter
was discovered on the edge of the YucatГЎn Peninsula, extending into the Gulf of Mexico. The Chicxulub Crater, as it was dubbed, was named for a
nearby village. Scientists believe the bolide that formed it was roughly 6 miles in diameter, struck the earth at 40,000 miles per hour and released 2
million times more

Cretaceous-Paleogene Boundary Essay
The Cretaceous–Paleogene boundary that occurred around 65 million years ago marks one of the three largest mass extinctions in the past 500 million
years. The hypotheses of Cretaceous–Tertiary boundary impact on YucatГ
Ўn Peninsula, Mexico shows evidence in the Gulf of Mexico of turbidity
currents, and giant waves occurring because of the impact. There is also other evidence that impact ejecta were distributed all over the world. The
mineral that was ejected during this impact was iridium. Iridium is a mineral that is commonly used to indicate a rock layer from the K–T boundary.
Iridium is only found naturally on extraterrestrial bodies. In addition to Iridium, shocked quartz is used to indicate the K–T boundary. Shocked quartz
is unique and... Show more content on Helpwriting.net ...
The four controls for a turbiditie sequence to form are tectonic activity, climate, sedimentary processes, and sea–level fluctuations. The mass of the
bolide that impacted the Yucatan Peninsula would have been large enough to irritate the plates, and possibly catalyze their movements. The suggested
size of the bolide is around 180 kilometers. The climate of the time can be closer examined by checking the paleontology of rock layers found before
and after the K–T boundary. Sedimentary processes and sea–level fluctuations could have taken a huge turn, due to the fact that an unexpected large
extraterrestrial body crashed into the Yucatan Peninsula. It is also suggested by geoscientists that a tsunami about 50 to 100 meters high hit the coast
of Texas, which resulted in an unconformity near Brazos River, Texas. The two major end members of a turbidite are coarse
–grained to sand–rich and
then fine–grained to mud–rich. These two end members are important because they are used in order to examine submarine fans. Submarine fans can
be geological clues as to what was going on in a particular layer of

KT Boundary Short Story
After Listening to the short story about what was a KT Boundary and the cause of the extinction of the Dinosaur, I learn so much about it. I was so
exited because when I was in five grade, I only learn that the dinosaurs die because a meteor hit Earth and all of the dinosaur died. In reality they
didn't die in one day in fact, they die because of many interesting reason.Melvyn Bragg and his guests discuss about what is a KtT boundary. I learn
that a Kt Boundary is break down in two parts, K stands for the Cretaceous period and the T stands for the Tertiary period.A K–T Boundary in Italy is a
Thin land of gray and is one centimeter thick and in central america it stretches about three centimeters but they are both a thin straight line.

Cretaceous Mass Extinction
The Cretaceous mass extinction had two theories on how and why it happened through the impact hypothesis. The first one was suggested that an
asteroid collided with Earth 65 million years ago. Luis Alvarez and his son, Walter Alvarez found "high levels of the rare metal iridium" in the layers
of the Earth during the periods of the Cretaceous and Tertiary located in Italy. Their proof is that it was the cause ofextinction by an asteroid the size of
10 kilometers. The second impact hypothesis was from a crater that was found buried off the coast of Yucatan, Mexico. Due to the material that was
thrown from the crater into the air, plant life could not receive sunlight to survive. The same goes for animals as the atmosphere was filled with
dangerous

The Cretaceous-Paleogene Boundary Essay
The Cretaceous–Paleogene Mass Extinction
Wil Creasy Student Number: 20921355
The Cretaceous–Paleogene boundary (K–Pg boundary) was host to one of the three largest mass extinctions in the past 500 million years. Evidence
suggests it was the result of a large asteroid impact approximately 65.5 million years ago in Chicxulub, Mexico; hence why the crater it formed was
named the Chicxulub crater. The crater was approximately 180 kilometres in diameter and was believed to have led to the extinction of the dinosaurs
amongst many other life forms including marine plankton (calcareous nannofossils and planktonic foraminifera) (Schulte et al., 2010). Furthermore, it
had a number of impacts on the atmosphere and environment including the creation of sulfuric acid rain and stratospheric dust cloud formations. ...
The deposit included a millimeter thick red clay layer that includes an iridium anomaly, ejecta spherules and nickel rich spinel (Schulte et al., 2010).
The age of the deposit coincides with the time of the mass extinction. It is coincidences such as this that have led scientists to believe that the mass
extinction and the Chicxulub impact are related.
The Yucatan–6 borehole provided significant evidence to suggest that there was an impact event that took place. The composition of the melt rock was
believed to have been the result of an impact rather than volcanic events (Kring and Boynton, 1992). What allowed scientists to confirm this, was the
surviving clasts of target rock they discovered within the melt, were similar to that seen In the Manicouagan impact crater. (Kring, 2007) Furthermore,
these clasts were said to be composed of shocked quarts and feldspar, which are indicative of an impact

Dinosaur Extinction Research

Recommended

Recommended

More Related Content

Similar to Dinosaur Extinction Research

Similar to Dinosaur Extinction Research (11)

More from Kim Johnson

More from Kim Johnson (20)

Recently uploaded

Recently uploaded (20)

Dinosaur Extinction Research