Extinctions

Welcome to Catnapin's

General Extinction Information

This page is under construction.

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The Precambrian

Archaean - Cooling crust allowed the first rocks to form, oldest found is 3.8 billion years. The atmosphere is mostly methane and ammonia. The oldest known fossil (stromatolite) is about 3.5 billion years old.

Proterozoic Era - The first true continents form. The largest forms of life are still bacteria and the archaeans, and they are plentiful. The first eukaryotic cells are possibly 1.8 billion years old. These comprise all the muliti-cellular protists, fungi, plants, and animals. The first "plants" used hotosynthesis to utilize food more efficiently. Their waste product was oxygen which accumulates in the atmosphere. Iron in the soil started to oxidize, forming the first "red bed" soils. The oxygen levels actually polluted the environment causing the first known mass extinction. Because of the extinctions and changing atmosphere, cells that could utilize the oxygen became plentiful.

Llano uplift of Texas contains rocks and stromatolite from this age.

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The Paleozoic

Late Ordovician - massive glaciers drain shallow seas, and drop sea levels. Mass Extinctions - 60% of all marine invertebrate genera

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The Permian

The largest mass extinction on Earth happened 250 million years ago. An estimated 95% of life came to an end with no asteroid to blame.

The environment during the second half of the Permian is that of change. Continental drift caused sea level to drop 820 feet, drying up the great inland Tethys Sea. Warm, humid climates of the vast coastal swamps were replaced by seasonal arid lands and deserts. Long droughts scourged the land. Species changed to survive or died.

At the end of the Permian, two major events separated by only 8 million years (a short time geologically) and many minor events devastated the planet. No iridium layer, shocked quartz, tektites, or crater have been found to implicate an impact in either of the Permian mass extinctions. Instead we find two massive and violent volcanic series in Southern China and Russia, called the Siberian Traps. (with map) These eruptions were hundreds of times bigger than anything in modern history. Lava beds cover an area twice the size of Europe and 2 ½ miles deep, and those beds have eroded since the Permian.

These enormous volcanoes darkened the Earth with ash and sulfur compounds every few hundred years. The large particles in the air may have dropped the average air temperatures by 20˚F, a serious amount when an average 1˚F change is considered significant. Sulfur combined with water vapor forming sulfuric acid, or acid rain. The high concentrations of acid dissolved limestone releasing carbon dioxide, triggering a greenhouse effect and raising temperatures dramatically. Warmer oceans escalate the release of carbon dioxide. Algae, which normally clean the air and oceans of carbon dioxide, are killed by the acidity. Plankton’s calcium shells also dissolve, disrupting the food chain and nearly killing the oceans. Within 25 years, the average temperature of the lower atmosphere would increase 18˚F. This cycle would repeat with each eruption.

Such extreme changes in light, temperature, and the percentage of carbon dioxide was too much for plants and animals leaving only the most resilient as survivors. In the ocean, many kinds of fish, the ancient rugose corals, giant forminifera, and blastoids vanish. Even the Trilobites, which had survived 380 million years and several mass extinctions, could not endure. On land, amphibians were devastated, barely surviving. All the basil synapsids and diapsids disappear leaving a remnant of Therapsids, Archosaurs, and lizards to replenish the Earth.

spread out

The Permian Environment and Mass Extinction (according to Dr. Courtillot)

The Permian environment is that of changes. For most of the Paleozoic Era, the climate remained consistently warm and humid. Land animals lived in swamps, rivers, and ponds, lush with cycads, conifers, ferns, and moss. Continental drift shifted the small continents into one large mass, Pangea, drying the great inland Tethys Sea. Mountain ranges formed, changing weather patterns. Instead of a constant warm damp weather, defined seasons disrupted life. Rain clouds no longer reached inland. Deserts soon occupied lands once lush. Some plant and animal faunas went extinct during this time. But as usual, others adapted to occupy open environmental niches.

Two extinctions at the end of the Permian record the largest mass extinction known in the fossil record. In the first, 90% of all species on Earth came to an abrupt end. The second adds casualties to the first running the total to 99%. Life nearly ended here.

If given time, plants and animals adapt to the new environments. The disappearance of shallow seas would affect those in it, but life would move to new locations. Trilobites had withstood extinctions before and survived for over 380 million years. This extinction exterminated the prolific trilobite.

Therefore something else had to happen to upset the balance, something that happened quickly in the geologic time scale.

Scientists have found two massive and violent volcanic series during this time. These eruptions were hundreds of times worse than anything in modern history. The first occurred in what is now Southern China. The second covered Siberia in lava. The two are “Hot-spots”, and together are called the Siberian Traps. They cover 350,000 square kilometers, 12,139 feet thick. Erosion has removed a great deal of the traps and an estimation of original coverage in excess of 2 million square kilometers has been proposed.

Every few hundred years or so another violent outpouring occurred. The volume of ash and sulfur dioxide gas would have darkened the whole Earth and dropped the air temperatures for years after each eruption. The outpouring of carbon dioxide gas would have heated the atmosphere (greenhouse effect).

Another theory concerns the oceans. Because of the greenhouse effect, caused by volcanoes, the oceans heated. Sulfuric acid, a byproduct of the volcanoes settled in the oceans and dissolved the limestone beds. This produced carbonic acid depriving the oceans of oxygen. As the oceans evaporated, carbonic acid changed to carbon dioxide in the atmosphere. This added still more power to the greenhouse effect. These extreme changes in light, temperature and the amount of oxygen, within short amounts of time, may have been too much for plants, animals, and fish, leaving only the most resilient as survivors.

No iridium layer, shocked quarts, tektites, or crater have been found to implicate an asteroid in either Permian mass extinctions.

Twice the size of Europe and 4 km deep (from the internet)

The Permian Extinction - 250 Ma (according to Dr. Courtillot)

From the beginning of the Permian the continent of Pangea began to break into Gondwanaland (south) and Laurasia (north). The large shallow Tethys Sea lay in between. At the end of the Permian, the sea level dropped 250 meters, possibly due to, the continental breakup and the massive hot-spot volcanoes in Siberia.

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The Triassic Mass Extinction

Near the end of the Triassic, dinosaurs accounted for only 6% of the animal population. Then two major events occurred to change in the population makeup. Within 7 million years, Dinosaur populations soared to 60%, and all the older forms were decimated.

The first event coincides with a crater in Manitoba, Canada. This was a relatively minor impact leaving a caldron 40 miles wide. Two more impacts occur 6 million years later: one in France with a caldron of 23 miles and one in Quebec, Canada at 100 miles. All these impacts were too small to result in worldwide extinctions but instead only affected regional areas.

More significant, is the volcanic activity that started about the same time as the first meteor. Two massive volcanic eruptions split North America from Europe and adversely affected the ecosystem. As in the Permian Mass Extinction, the atmosphere would have altered dramatically within short periods of time. The breakup of the large northern continent would have altered weather patterns. Between the impacts, volcanic activity, and the quick continental movements, the Earth became intolerable to many life forms. A few animals, like Dinosaurs, benefited from the changes and became dominant.

“…the Carnian-Norian extinction event. The dicynodonts, chiniquodontids, and rhynchosaurs all died out. These three families had made up 40 to 80 percent of all the late Carnian faunas, representing the dominant medium-sized and large herbivores worldwide. Other groups that disappeared at this time were temnospondyl amphibians, archosauromorphs, basal archosaurs, and some dinosaurs (Herrerasauridae). Hence, ten of the twenty-four late Carnian families died out (a loss of 42 percent)…”

“… There were other extinctions at, or close to, the Carnian-Norian boundary among marine organisms… At this time, there was a world wide series of climatic changes from humid to arid that may have been triggered by events associated with the beginning of rifting of the supercontinent Pangaea. Major floral changes occurred, too, with the disappearance of the Dicroidium floras of southern continents, and the spread worldwide of northern conifer-dominated floras. Perhaps the drying climates favored conifers over seed-ferns such as Dicroidium, and perhaps the dominant Carnian herbivores were unable to adapt to new Kinds of vegetation, and died out.”

220 mya between the Carnian and Norian ages	Extinction	then a dramatic diversification of dinosaur species Carnian - dinosaurs are less than 6% of the population Norian - dinosaurs are less than 25-60% of the population
214 mya near Manicouagan in Quebec	Impact crater	affected only local populations
200 mya	Hot Spot volcanism	two large traps start to open the mid-Atlantic Ridge splitting NE North America and NW Africa
202 mya between the Triassic and Jurassic periods	Extinction	then a dramatic diversification of dinosaur species to become the dominant land animals
180 mya early Jurassic/middle Jurassic boundary	Hot Spot volcanism	large trap splits Antarctica from South Africa - Gondwanaland split

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The Cretaceous Mass Extinction

After 150 million years of ruling the world, the dinosaurs vanished. Another mass extinction hit the world. Was it in the form of a giant meteorite, volcanoes, or both?

The Killer Meteorite

In 1980, Luis and Walter Alvarez predicted finding a giant impact crater dated at 65 million years. They had studied a thin layer that lay at the end of the Cretaceous. It was rich in iridium that pointed to extraterrestrial origins.

This crater was found off the northwestern edge of the Yucatan. It is called the Chicxulub impact crater. The structure is circular, nearly 180 miles in diameter, and buried under 2 miles of sediment. The only craters found that rival its size or larger are over 1.8 billion years old.

The meteorite hit the Earth on continental crust in a shallow sea, vaporizing the Yucatan bedrock with an equivalent of 100 Gigatons of TNT. An earthquake of 10 to 12 on the Richter scale triggered earth slides and a gigantic tsunami. The largest recent earthquake measured 8.9 on the Richter scale.

Mass quantities of carbon dioxide and sulfur dioxide were released from the vaporized bedrock. The heated particles of fallout started large fires, burning forests worldwide. Any plants left may have died from the cold and burned later from lightning strikes. It has been estimated that almost all living matter burned. Fire, from plants and oily shales, added high levels of arsenic, antimony, zinc, and hydrocarbons into the atmosphere. The heat and gasses would soon change the impact winter into the greenhouse effect.

The term “nuclear winter” was coined from “impact winter” used to describe the aftermath of a large meteor strike.

The Geologic Record at the K/T Boundary

All findings connect the iridium layer, crater, and the K/T boundary. No other mass extinction event has been associated with a similar layer.

The K/T Boundary marks the second largest mass extinction in Earths history. Of all the dinosaurs, only birds survived. 75% of all the land and sea species became extinct. Still, from the fossil record this extinction did not happen in one event. It took 400 thousand years. Many species actually became extinct within the next million years after the impact.

India’s Deccan Traps

50 Ma, Earth’s greatest continental collision occurred: the island of India rammed into Asia, forming the Himalayan Mountains. The magnetic rocks from the southern part of Asia are still oriented as they were at the time of the collision. India’s rocks show it started its journey at 15°N latitude, more than 900 miles south of its present position.

What relocated India is called a hot-spot volcano. The Deccan Traps is an area in western India where over 50 major successive eruptions covered the land in layers of lava. Fissures, up to 250 miles long, crisscross the region. Each lava flow is more than 650 feet thick and 700 miles across. Only two magnetic field reversals are recorded within these layers. That indicates less than half a million years of active volcanism, an incredible amount of lava produced in a very short time.

The Deccan Traps start one or two hundred thousand years before the K/T iridium layer, and end one or two hundred thousand years afterward. Each of the major eruptions would have lasted several years and be separated by a few thousand years. Suspended particles and gasses would have reduced the amount of sunlight to that of a full moon for one to ten years at a time.

India’s Deccan Traps

These events would The greenhouse effect would increase the temperature of the lower atmosphere by more than 10°C 18°F (1/2°C is considered a significant event).

Massive hot-spot eruptions have occurred many times in the last 400 million years.

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Volcanic Traps, Mass Extinctions, and Impact Craters

There are two extinctions at the end of the Devonian (365 & 355 Ma). Extensive volcanism in western Russia including rifting and uplift are indicated. The area has not been studied extensively but a hot-spot is indicated.

The largest mass extinction of all time ended Permian in two phases (258 & 250 Ma). Hot-spot volcanism in southern China and Siberia are directly responsible.

The Triassic ended (200 Ma) at the same time hot-spot eruptions at Azores and Meteor Islands split North America from Africa opening the Atlantic Ocean. A large crater (100 km wide) in Quebec, Canada is dated slightly earlier than the eruptions at 214 Ma. It is thought to have caused only regional extinctions.

The Jurassic holds several major events. 180 Ma the Karoo hot-spot split Antarctica from South Africa. Only regional extinctions are recorded. The end of the Jurassic corresponds to two hot-spot eruptions that split South America from Africa (133 Ma). Five impact craters 20-80 km wide are found during the Jurassic. Only one corresponds to a small extinction.

The Cretaceous has four traps. The first helps drive Antarctica farther away from Africa 116 Ma. An impact crater is dated from this same time (115 Ma) in Saskatchewan, Canada. No mass extinctions coincide with either. The second trap (110 Ma) is very extensive but totally underwater in the South Pacific Ocean, so no extinctions occurred. The third split Madagascar from Africa (90 Ma), but did not cause a mass extinction. The forth combined with a very large meteor and ended the Cretaceous and the dinosaurs 65 Ma.

The Paleocene ends in two stages of eruptions (59 & 56 Ma), which cover the area in up to 3000 m of lava. The hot-spot separates North America from Europe, leaving Iceland over the hot-spot.

The Eocene does not have a hot-spot. Instead, near the end two large impact craters 35 to 36 Ma may have caused enough regional damage as to end the age. Popigai, Russia, is 35.7 Ma and 100 km wide. Chesapeake Bay in Virginia is 35.5 Ma and 90 km wide.

The Oligocene’s Afar hot-spot opens the Red Sea 30 Ma but causes only regional extinctions. A impact crater in Nunavut, Canada corresponds to the end of the age 23 Ma. But it is too small to have caused a world catastrophe.

In the Miocene (16 Ma), the Columbia River Trap erupted causing regional extinctions only. This hot-spot is what gives Yellowstone National Park its geysers, hot pools, and earth quakes.

Many more small hot-spots occur in the oceans, leaving trails of islands as the continental plates slide by. Dating the origin of these systems is not easy. The first island masses have been lost to subduction under other plates.

The Shape of the Earth

The continents looked very different then they do today. North America had split from Africa at the end of the Triassic. South America and Africa split at the end of the Jurassic. The Rocky and Andes Mountains were smaller but new and violent. When these volcanoes were active the continents rose. When inactive the continents subsided. The oceans rose and fell hundreds of feet and many times during the Mesozoic Era. Underwater the North America continent was divided in two sections of lush primal forests and ocean front savannas. Occasionally this shallow ocean extended all the way to the Arctic Ocean. This cycle was broken about 65 Ma.

65 Ma the Himalayan Mountains did not exist.

The climate of the Mesozoic was hot. The equator was dryer, sometimes arid. The poles were not ice bound. In fact dinosaurs lived on Antarctica.

Jurassic period (208 to 144 million years ago). First large dinosaurs arrive. Mammals remain very small and rodent like.

At the end of the period a large comet hit the island of India speeding up it’s movement and eventual crash into Asia making the Himalayan mountain range. Directly across the globe massive volcanoes erupted and split the continent of Pangea. The present day continents of South America and Africa were slowly pulled apart by the turbulence inside the Earth, resulting in the Mid-Atlantic Ridge. This ridge is still moving the continents apart. The largest water falls on earth are the Iguazu in northern Argentina. They are 240 feet high and twice the width of Niagara. The water cascades down 130 million year old lava flow steps. The steps in the falls show individual lava flow layers. Each layer covered an area larger than the state of Texas. The stone from the flows match stone in Africa exactly, proving that the continents were once one. Because of the continental split, animal populations that were very similar, soon became distinctly different.

In the 1970, near Gubbio, Italy, Luis and Walter Alvarez studied a thin layer from the end of the Cretaceous. This credit card thin clay layer separated two layers of limestone. The clay is rich in iridium, an element rare in Earth rocks but common in asteroids and comets. This layer is found all over the world and is thicker in the America’s.

You have all heard of that collision but did you know that it may have been aided by volcanoes in northern India, now known as the Deccan Traps? This was a huge range of volcanoes, similar in size to the ones in Russia at the end of the Permian. About the same time as the impact, production of lava greatly increased, adding deadly gasses into the atmosphere. The relationship between these two major events is still under investigation.

The K/T Boundary and the Meteor Impact - 65 Ma (according to Dr. Courtillot)

In 1977 Walter Alvarez (a geologist) asked his father, Luis (a physicist) to study a slice of stone from the Gubbio section, Italy. Three layers were represented. The lowest was white limestone with Cretaceous Foraminifera. The thin (2 cm) center layer was dark clay and was without any visible life forms. The top layer was Cenozoic and showed a slow resumption of life.

To determine the length of time the clay layer recorded, Luis Alvarez measured the amount of iridium in the sample, using the new technique of neutron activation. Iridium is a rare element in the Earth’s crust but is rich within micrometeorites that rain into our atmosphere constantly. This technique has become the standard for measuring sedimentation rates. The layers below contain a few tenths of a part per billion of iridium. The clay layer contained 9 parts per billion, 30 times higher. The above layer concentrations had high elevations up to 15 cm above the clay.

The iridium layer is found in all surviving K/T boundary locations, world wide, and distributed in all kinds of deposition environments, both oceanic and continental.

Found in the layer are small spheres, called tektites, made of oceanic basalt particles heated and melted as they fly through the air. Tektites are produced through impact only.

Shocked quarts is found in the layer. This kind of microscopic defect has only been found in nuclear explosions, projectile impacts in laboratory tests, and undisputed meteorite impacts.

Zircon crystals in the layer have been dated to 400 million years old that have gone through a considerable shock and thermal event.

Large fires, from organic materials, added abnormally high levels of arsenic, antimony and zinc to the atmosphere, water, and sediments. Thick layers of oil shale may have been exposed by the withdrawal of the seas at the end of the Cretaceous Period and might have caught fire, sending hydrocarbons into the atmosphere.

The Alverez Impact Theory was published in 1980. The scenario has a meteorite, with a diameter of approximately 10 kilometers, plunging into a shallow ocean. The impact would release a kinetic energy equivalent to 100 million megatons of TNT. The meteorite digs a hole in the atmosphere and earth’s crust. Pulverized rock is shot into the atmosphere, producing considerable heat and producing nitrogen oxide from the gasses in the air. The dust takes months or years to settle and shuts-out sunlight, arresting photosynthesis, causing a long, cold winter. Fires produce soot and more nitrogen oxide. Nitrogen oxide combines with water in the air producing nitric acid, which destroys the ozone layer and falls to earth as acid rain. On land acid rain would damage the surviving land plants. In the ocean it kills plankton by dissolving their skeletons (shells) made of calcium.

The Chicxulub impact crater is off the northwestern edge of the Yucatan with a circular structure nearly 300 kilometers in diameter and buried under 3 kilometers of sediment. It is one of the largest impact structures inside the asteroid belt since the great bombardment ended nearly 4 billion years ago. The meteor hit the Earth 65 Ma on continental crust in a shallow sea. The impact triggered an earthquake of 10 to 12 on the Richter scale, triggering earth slides and a gigantic tsunami. The asteroid would have produce mass quantities of carbon dioxide and sulfur dioxide when it vaporized the Yucatan bedrock (carbon from limestone, sulfur from gypsum and anhydrite).

The heated particles of fallout started large fires, burning forests worldwide. Any plants left may have died from the cold and burned later from lightning strikes. It has been estimated that almost all living matter burned. The heat and gasses would soon change the impact winter into the greenhouse effect. Combustion releases carbon monoxide and organic toxins in quantities that induce mutations. Few animals could survive the extreme temperature change without mutating.

The term “nuclear winter” was coined from “impact winter” used to describe the aftermath of a large meteor strike.

No known mass extinction boundaries, other than the K/T, have elevated concentrations of iridium. So far, all other impact craters do not correspond with known extinctions or magnetic field reversals. An impact the size of Chicxulub is not large enough to strip away enough crust and melt enough upper mantle required to trigger a hot-spot eruption.

At the end of the Cretaceous the sea level of the vast inland ocean lowered but not as much as the end of the Permian. This may be caused by the hot-spots the Deccan Traps and in Russia.

There are meteorites over 1 meter across entering the Earth’s atmosphere every year. Most burn-up or explode during entry. Those that do reach land, devastate the immediate population but do little harm elsewhere.

Evidence indicates a decrease in annual rainfall and a huge drop in temperature (25˚C to 15˚C) before the K/T boundary. (BBC news report)

Volcano releases sulfur into atmosphere

sulfur + water = sulfuric acid

sulfuric acid + limestone = releases (produces) carbon dioxide and forms a calcium salt

carbon dioxide + water = lowers the pH of water, acidifying the water

carbon dioxide is usually absorbed by algae.

Excerpts from the Book

Evolutionary Catastrophe: The Science of Mass Extinction

by Vincent Courtillot (a specialist in Paleomagnetism)

Miscellaneous

“Species disappear every year.” Pg vii

There are profound breaks in the line of species that led nineteenth century science to define the great geological eras. Pg vii

“…over 99.9% of the species that ever lived on Earth are already extinct.” Pg 4

The extinction rate is approximately “one family per million years”. Pg 12

“Typically, the mean sedimentation rate is in the order of one centimeter per thousand years, over an interval of one million years; but it rises to several meters per thousand years on the thousand-rear scale.” Pg 14

“In general, it was the larger and the more ‘specialized’ animals that vanished, while the smaller ones and the ‘generalists’ pulled through rather well.” Pg 16

Life On Earth

Earth formed about 4.5 billion years ago. Pg 1

Multicellular organisms developed only 700 Ma. Single celled organisms had been around for nearly 2 million years. Pg 1

Skeletons develop around 600 Ma, that is, hard parts that fossilize. Pg 1

The seas were populated by fish by 500 Ma. Pg 1

By 400 Ma amphibians begin developing into reptiles. Pg 1

Warm blooded proto-mammals arrive about 260 Ma. Pg 1

At the end of the Paleozoic age (Permian 250 Ma), 90% of all species of animals suddenly die. A second catastrophe happens shortly afterwards to make the total over 99% of all species. Pg 1-2

During the Mesozoic era dinosaurs grow large and mammals stay small. Then 65 Ma another great catastrophe happens, killing 75% of all species of animals, including all the dinosaurs. In general, the larger “specialized” animals vanished, leaving the smaller “generalized” animals to survive. The diversity and abundance of marine invertebrates begin declining a few hundred thousand years before the K/T boundary. At the boundary there is an abrupt rise in mortality. After the boundary, marine invertebrates decline for a few more hundred thousand years before becoming abundant again.

By 50 Ma we find the ancestors of most of the animals living today and modern fauna dominates 30 Ma.

The K/T Boundary and the Meteor Impact - 65 Ma

“The marine invertebrates, such as the mollusks, do not furnish a very clear picture. Their diversity and abundance decline a few hundred thousand years before the boundary, and then at the boundary itself.” Pg 18

“… a gradual extinction, caused by the slow drop in sea level at the end of the Cretaceous was followed by a final, abrupt extinction.” Pg 18

“… the main part of our observations and interpretations of the KT crisis is now founded on the massive and apparently catastrophic extinction of almost all species of marine Foraminifera …all planktonic Foraminifera (except one) had suddenly died out at the KT boundary. … nearly one-third of the species disappear at this level, an equal quantity disappear earlier, 25 cm deeper down, and the rest in several stages above. … the crisis that led to the disappearance of these species apparently was not instantaneous.” pg 18-20

“… the biological crisis began at least 100,000 years before this famous boundary and continued for about as long after. …punctuated with phases that were more abrupt, but about which we cannot say for sure whether they lasted less than a day or more than a thousand years. …the ecosystems took more than 500,000 years to really recover.” Pg 21

“… linked with a drop in sea level and a slower rate of sedimentation …” pg 22

In 1977 Walter Alvarez (a geologist) asked his father, Luis (a physicist and Nobel laureate) to study a slice of stone from the Gubbio section, Italy. Three layers were represented. The lowest was white limestone with Cretaceous Foraminifera. The thin (2 cm) center layer was dark clay and was without any visible life forms. The top reddish limestone layer was Cenozoic and showed a “slow resumption of life.” Pg 23

To determine the length of time the clay layer recorded, Luis Alvarez measured the amount of iridium in the sample, using “the new technique of neutron activation”. Iridium is a rare element in the Earth’s crust but is rich within micrometeorites that rain into our atmosphere constantly. This technique has become the standard for measuring sedimentation rates. The layers below contain a “few tenths of a part per billion” of iridium. The clay layer contained “9 parts per billion, 30 times” higher. The above that layer concentrations had “abnormal values” for “15 cm above the clay”. Pg 24-25

Dennis Kent (colleague of W. Alvarez) “was the first to suggest that the events responsible for mass extinction had lasted less than 10,000 years.” Pg 31

The iridium layer is found in all surviving K/T boundary locations, world wide, and distributed in all kinds of deposition environments, both oceanic and continental.

Found in the layer are small spheres, called tektites, made of oceanic basalt particles heated and melted as they fly through the air. Tektites are produced through impact only. Pg 38

Shocked quartz is found in the layer. This kind of microscopic defect has only been found in nuclear explosions, projectile impacts in laboratory tests, and undisputed meteorite impacts. Never found in volcanic eruptions. Pg 38, 68

“Zircon, or zirconium silicate, is a semiprecious stone highly resistant to heating and alteration that incorporates small quantities of uranium a the time of its crystallization.” have been dated to 400 million years old that have gone through a shock and considerable thermal event. Pg 41

“Thick layers of oil shales may have been exposed in abundance by the withdrawal of the seas at the end of the Cretaceous Period and could have caught fire spontaneously…” pg 42

The Alvarez Impact hypothesis/theory was published in the journal Science, 1980. The scenario has a meteorite, with a diameter of approximately 10 kilometers, plunging into a shallow ocean. The impact would “release a kinetic energy equivalent to 100 million megatons of TNT”. The meteorite digs a hole in the atmosphere and Earth’s crust sending shock waves around the world. Pulverized rock is shot into the atmosphere, producing considerable heat and producing nitrogen oxide. The dust takes months or years to settle and shuts-out sunlight, arresting photosynthesis, causing a long, cold “impact winter”. “Thick layers of oil shales may have been exposed in abundance by the withdrawal of the seas at the end of the Cretaceous Period and could have caught fire spontaneously…” Fires from the initial fireball and then lighting produce soot, “carbon monoxide and organic toxins (such as dioxin) in such quantities that these products may induce mutations”, and more nitrogen oxide. It is estimated “that almost all living matter, the biomass, burned.” Nitrogen oxide combines with water in the air producing nitric acid, which destroys the ozone layer and falls to earth as acid rain. On land acid rain would damage the surviving land plants. In the ocean it kills plankton by dissolving their skeletons (shells) made of calcium. Plankton absorbs carbon dioxide from the atmosphere. Deccan Traps “injected ten times more carbon dioxide into the atmosphere than the atmosphere contains today.” In a “dead ocean” scenario the atmospheric carbon dioxide would double in 25 years. Carbon dioxide contributes to a greenhouse effect. Pg 25-33, 42-43, 59 [mine] The heated fallout particles started large fires, burning forests worldwide. Any plants left would have died from the cold and lack of light, then burn from lightning strikes. It has been estimated that almost all living matter burned. The heat and gasses would soon change the impact winter into the greenhouse effect. Combustion releases carbon monoxide and organic toxins in quantities that induce mutations. Few animals could survive the extreme temperature change without mutating.

The term “nuclear winter” was coined from “impact winter” used to describe the aftermath of a large meteor strike.

At the end of the Cretaceous the sea level of the vast inland ocean lowered but not as much as the end of the Permian. This may be caused by the hot-spots the Deccan Traps and in Russia. Pg 17

Other meteors/comet craters

It is estimated that a 10 km meteor will hit the earth every 50 to 500 million years. Pg 36

50 Ma, Nova Scotia, Montagnais Crater, 50 km wide, “had no effect on the diversity of species, even on a merely regional scale.” Pg 36

75 Ma, edge of the Arctic Ocean, the twin craters of Kara and Ust Kara, 65 km wide and more than 80 km wide, “had hardly any consequences when their meteorites fell to Earth some ...” Pg 36-37

1908, Siberia, the Tunguska comet burned 2000 km² of forest “at an altitude of 10 km …” Pg 37

The Permian Extinction - 250 Ma

From the beginning of the Permian the continent of Pangea began to break up into Gondwanaland (south) and Laurasia (north). Evidence of the Tethys Sea that lay between has been nearly obliterated by the movements of the continents but there is enough left in the European Alps and the Himalayas to correlate a mid-sea ridge and subduction zones around the sea. At the end of the Permian the sea level dropped 250 meters, possibly due to, the continental breakup and the massive hot-spot volcanoes in Siberia.

There are two brief, intense crises at the end of the Permian. One at the end of the Guadalupian (next-to-the-last Permian formation)(Emeishan Traps of southern China), where 90% of all species of animals, land and sea, suddenly die. A second catastrophe (Siberian Traps) 8 million years later at the end of the Tatarian (the last Permian formation and end of the Paleozoic Era), combined to total over 99% of all species, existing at the time, becoming extinct.

There is no iridium layer, shocked quartz, or tektite. There is a drop in atmospheric oxygen and an increase in its carbon dioxide.

At the end of the Permian most of life on Earth became extinct. The fusulinids, a giant Foraminifera that are a worldwide fossil marker for the Permian, died. Reef-building crinoids, bryozoans and brachiopods and almost all the nautiloids disappeared. On land only one genus in a hundred survived.

The two Siberian Traps cover 350,000 square kilometers and has a maximum thickness of 3700 meters. Erosion has removed a great deal of the traps and an estimation of original coverage in excess of 2 million square kilometers has been proposed. The oldest beds are 250 million years old, with only one magnetic reversal. The dozens of eruptions had highly explosive phases with heavy sulfur emissions.

The Triassic/Jurassic Extinction - 200 Ma

Almost as intense as the K/T extinction

During the Triassic the continents were still gathered together as Pangea. At the end of the Triassic the seas regressed.

All ammonites, half the genera of bivalves and many brachiopods and gastropods became extinct (actually more than the Permian extinction). It takes 10 million years before the corals and sponges regroup. The conodonts, a prevalent fish that survived the Permian extinction, died. In contrast the Foraminifera only lost 20% of its families. On land 80% of the quadrupeds became extinct and flora made major changes.

After this extinction the dinosaurs start to grow large and dominate the world.

Two hot-spots opened the central Atlantic Ocean, leaving traps along the North American coast and some on the northwest tip of Africa.

The Manicouagan Crater in Quebec, a 70 km diameter impact crater was thought to be the cause but it arrived 20 million years to early.

The Jurassic/Cretaceous Extinction - 133 Ma

This boundary has not been studied well and values between 130 & 145 million years have been proposed. 133 Ma the Parana Traps in Brazil began with only one magnetic field reversal evident. The Iguaca Falls descend the traps. On the west African coast is the Walvis Ridge, part of the these same traps. The Tristan da Cunha hot-spot opened the South Atlantic.

The Paleocene/Eocene Extinction - 56 Ma

The North Atlantic Tertiary Volcanic Province marks the birth of the Iceland hot-spot and the opening of the Far North Atlantic. There are two pulses, 59 & 56 Ma, the second is the boundary. There is only one magnetic field reversal between the two.

The Greenland half of the traps is 3000 meters thick. The other half is the northwest margin of the British Isles and the Norwegian continental plateau.

The mass excitations at the end of the period killed off all the dinosaurs, and most of the large reptiles, about 76% of the living species, enabling the small mammals to flourish. It was caused by a large comet (the size of Mount Everest) that smacked into the Yucatan peninsula 65 million years ago. This is known as the Chicxulub impact crater. They say it had a force greater than all the nuclear weapons on Earth today being blown up together in one spot. There was enough heated dust thrown into the air to darken the sky for several months. It may have been dark enough to shutting off photosynthesis killing most of the plant species. That would cause the end of the herbivores and then the carnivores in a very short time.

The present day continents of South America and Africa were slowly pulled apart by the turbulence inside the Earth, resulting in the Mid-Atlantic Ridge. This ridge is still moving the continents apart. The largest water falls on earth are the Iguazu in northern Argentina. They are 240 feet high and twice the width of Niagara. The water cascades down 130 million year old lava flow steps. The steps in the falls show individual lava flow layers. Each layer covered an area larger than the state of Texas. The stone from the flows match stone in Africa exactly, proving that the continents were once one. Because of the continental split, animal populations that were very similar, soon became distinctly different.

Rising oxygen levels could have also been responsible for the periods of extreme glaciation (the snowball theory) about 2300 million years ago and then several times between 750-580 million years ago. During those times, all the continents were under ice, even near the equator. The oceans could have been frozen a half mile deep. Volcanoes spewing carbon dioxide countered the effect about 10,000 years after each episode.

Two major environmental events happened at the end of the Ordovician: a long ice age and a large mass extinction, which ended this period. Neither has been studied in depth. One reason is there are few stone beds left of this time. The proliferation of advanced jawed fish resulted.

(this line is used under Tetrapod) A large mass extinction ended the Devonian Period with nearly all the precursors to the Tetrapod line becoming extinct. Even though this extinction was larger than the one at the end of the Cretaceous, it has not been studied extensively.

Time Line Trivia

Fish and aquatic amphibians generally have very heavy skulls. In fact they were quite solid. buoyancy of water

In the middle of the Carboniferous Period the synapsids diverged from the anapsids.

Diapsids appeared in the Late Carboniferous Period. By the beginning of the Permian Period (285 Ma), the diapsids split into two divergent lines. One line leads to the snakes and lizards, the other archosaurs. One of the distinguishing characteristics of archosaurs is the presence of an additional hole on the snout in front of the orbit.

Pelycosaurs (Eupelycosauria) were a large group of early Synapsid tetrapods. There were carnivores and insectivores, and herbivores. They appear in the Late Carboniferous (300 Ma) and became the dominant animals of the Early Permian. There were noticeable extinctions at the end of the Early Permian and at the end of the Middle Permian. Only a handful of species survived the Permian/Triassic Mass extinction. Two families survived into the Jurassic and one of those into the Early Cretaceous.

From an early sphenacodontid the Therapsids evolve. They became the dominant animals of the Middle Permian and may have become warm blooded at this time. Therapsids did not have scales like reptiles, but they may not have had fur until the late Permian.

One group of Therapsids were the Theriodontia ("beast tooth" with mammal-like teeth) that appear 265 mya in the Middle Permian. Bones in the head supporting the jaws shift. Some allow the jaw to open wider than the other reptiles and some become part of the ear for better hearing. These animals had larger teeth. They all had larger skulls, improved jaw muscles, and specialized teeth that were not continuously replaced.

A survivor of the Permian/Triassic mass extinction were the Therodontia suborder Cynodontia ("dog teeth". These animals developed an upright gait. At first some grew to 6 feet long, but by the end of the Triassic they were all very small.

(Courtillot) Of the 25 different anatomical plans developed during the Cambrian Period, only four survived; one of these had the beginning structure of a backbone.

Lungfish were modern by the end of the Devonian. Coelacanths were modern by the Triassic..

By the Carboniferous, Tetrapods had amniotic eggs. This is a form of reproduction where the fetus grows within a protective egg and does not need to live in water after hatching, unlike amphibians. Thus all true land animals are in the superclass called Amniota.

All true dinosaurs known are Carnian (probably late) in age (the earliest part of the Late Triassic), same time as the Petrified Forest Formation from Arizona.

The Dissorophoid group, Cacops, with massive head, short bulky body, ossified vertebrae, and armor on top of the vertebrae were terrestrial. One animal, Platyhystrix, had a sail made from its armor. Doleserpeton of Oklahoma has been suggested as a possible relative to frogs.

Permian Period

The original theory of continental drift was proposed in 1912 by German meteorologist Alfred Wegener. Though all of the pieces of his theory seemed to fit, scientists rejected continental drift. But due to research of seafloor movement by wartime forces, continental drift grew in acceptance by the end of World War II. The current vision of Continental Drift is called Plate Tectonics, and considers a wider volume of geologic data to support the theory.

The Earth at the beginning of the Permian Period had only one continent called Pangaea, which is Latin for "all land." This land mass, in the form of a giant "C", contained no polar ice and had a very low sea level. Only a few pieces of land were unattached from Pangaea—modern day northern and eastern China, Indochina, and parts of Central Asia—were found to the east of the larger continent.

At the end of the Permian, severe climatic fluctuations produced significant cooling and drying in the temperate zones. Glaciation was prominent over the poles and multiple ice ages may have occurred.

Triassic Period

In approximately 25 million years, Pangaea split into two continents—Laurasia and Gondwana.

During the early Triassic Period the continental plates of Pangaea began to spread apart. We call the northern group Laurasia and southern group Gondwanaland. They were separated by the Tethys Ocean.

Two massive volcanic eruptions occurred at the end of the Triassic Period, now called the Azores and Meteor islands. They opened the early Atlantic Ocean and moved the continents of North America and Africa apart.

Jurassic Period

In the Jurassic period, continents with the shapes we recognize formed. North and South America move farther apart as the rifting of the new seafloor continued and opened the Gulf of Mexico.

In the middle of the Jurassic, Antarctica splits from South Africa with only a regional extinction.

At the end of Jurassic the main plate of Gondwanaland splits into two, forming Africa and South America, and the southern Atlantic ocean.

Cretaceous Period

The Cretaceous was warm and humid. For most of the period, sea levels were very high, covering continents with large, shallow, inland seas. The Earth looked like a series of islands. The young Rocky and Andean Mountains began forming in the late Cretaceous as the American continents slammed into the Pacific Ocean plates.

At the end of the Cretaceous Period, a series of violent volcanic explosions broke India from Africa. The new continent moved so fast that its collision with Asia formed the Himalayan Mountains.

Paleocene

North America and Europe split, forming the north Atlantic Ocean and Iceland, at the end of the Paleocene.

The drift of continental plates has changed the world of yesterday to the one we know today. Oceans have risen and fallen. Mountains grow and then eroded away. Life changes along with the world, taking advantage of the good times and surviving the bad.

During the Jurassic: North America had split from Africa at the end of the Triassic. South America and Africa split at the end of the Jurassic. The Rocky and Andes Mountains were small but new and violent. When these volcanoes were active the continents rose. When inactive the continents subsided under the ocean. The oceans rose and fell hundreds of feet and many times during the Mesozoic Era. Underwater the North America continent was divided in two sections of lush primal forests and ocean front savannas. Occasionally this shallow ocean extended all the way to the Arctic Ocean. This cycle was broken about 65 Ma.

End the Cretaceous: 64 Ma the Himalayan Mountains did not exist and India was an island. The massive volcanic activity in Northwest India drove the subcontinent, crashing it into Asia.

All true dinosaurs known are Carnian (probably late) in age (the earliest part of the Late Triassic), same time as the Petrified Forest Formation from Arizona.

The red clay hills are about 1/3 into the Permian. The geologic name is Paleozoic era, Permian period, Vale of the Clear Fork formation. There are three layers within the Clear Fork formation, ours is in the middle.

Notes: Permian per internet Palaeos

http://www.palaeos.com/Paleozoic/Permian/Permian.htm

Supercontinent of Rodinia; single ocean Iapetus; fragmented towards the end of the Proterozoic

650 Ma Vendian continents of Pannotia, Siberia, and North China; Pannotia fragmented into Laurentia, Gondwana, and Baltica

in Devonian and Carboniferous 350 Ma drifted back together, in Permian-Carboniferous 350-260 Ma Gondwanaland, Euramerica, and Siberia became Supercontinent of Pangea, small block of southeastern Asia were late arrivals, Spain and central France were part of Venezuela, Complete by the Kungurian of Permian

End of Carboniferous and beginning of Permian ice age covers much of Gondwanaland, tropics are swampy forests; mid-Permian warmer and milder, glaciers recede, continental interiors arid seasonal fluctuations; end of Permian sea levels drop and sallow seas decline; drier let conifers and ginkgos become prominent plants and reptiles dominant animals

Animals; Pelycosaurs – Dimetrodon, Edaphosaurus, Ctenospondylus, Secodontosaurus – all 3 m, sails and no sails, all equatorial tropics; Dinocephalian (fearsome head) of the Guadalupian succeeded the Pelycosaurs, primitive therapsids, 5-6 m, meter long heads, primitive Anteosaurs are carnivore, Tapinocephalia are herbivores, Pareiasaurs big herbivores, Mid-Permian all extinct; Therapsids, smaller but more mammal-like, maybe fur and warm-blood, Gorgonopsians carnivore, Therocephalia, dicynodonts herbivore, Pareiasaurs lived till the end of the Permian.

Trilobites extinct at end of Permian

by Norian of Triassic Gondwanaland moved till Africa abutted North America; “Pacman” shaped with mouth to the east; single ocean Panthalassa; single inland sea Tethys

Break up in early to mid- Cretaceous 130-100 Ma; most of the time the supercontinent was a series of large islands, separated by shallow seas.

The environment during the second half of the Permian is that of change. Sea level dropped 820 feet in the great inland Tethys Sea. Where there were coastal swamps, arid lands now dominated. Hot, humid climates became dryer and seasonal.

The Shape of the Earth

The continents looked very different then they do today. North America had split from Africa at the end of the Triassic. South America and Africa split at the end of the Jurassic. The Rocky and Andes Mountains were smaller but new and violent. When these volcanoes were active the continents rose. When inactive the continents subsided under the ocean. The oceans rose and fell hundreds of feet and many times during the Mesozoic Era. Underwater the North America continent was divided in two sections of lush primal forests and ocean front savannas. Occasionally this shallow ocean extended all the way to the Arctic Ocean. This cycle was broken about 65 Ma.

65 Ma the Himalayan Mountains did not exist.

The climate of the Mesozoic was hot. The equator was dryer, sometimes arid. The poles were not ice bound. In fact dinosaurs lived on Antarctica.

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