Plate tectonics of the North American Continent at the

Cretaceous-Tertiary Boundary, and Implications For a Terrestrial Cause in

the Great KT Extinction

Controversy

The Great KT Extinction The Great KT Extinction ControversyControversy

• Before 65 mya, during the Cretaceous Before 65 mya, during the Cretaceous (K), dinosaurs had roamed the Earth.(K), dinosaurs had roamed the Earth.

• But by the beginning of the Tertiary But by the beginning of the Tertiary (T), 65 million years ago (mya), a mass (T), 65 million years ago (mya), a mass extinction had occurred that wiped out extinction had occurred that wiped out nearly 75 % of life on Earth, including nearly 75 % of life on Earth, including the dinosaurs.the dinosaurs.

• This is known as the KT Extinction This is known as the KT Extinction Event Event

• In 1980, Dr.’s Louis and Walter In 1980, Dr.’s Louis and Walter Alvarez discovered a layer of clay at Alvarez discovered a layer of clay at several sites along the KT boundary several sites along the KT boundary that contained high levels of iridium, that contained high levels of iridium, as well as other exotic materials. as well as other exotic materials. (Alvarez, 1980)(Alvarez, 1980)

• Since iridium is rare in Earth’s crustal Since iridium is rare in Earth’s crustal rocks, the Alvarez team proposed rocks, the Alvarez team proposed that the layer had been formed by an that the layer had been formed by an Extraterrestrial source, such as an Extraterrestrial source, such as an asteroid. asteroid.

• So far, this has been the most widely So far, this has been the most widely accepted hypothesis. accepted hypothesis.

• In 1981, however, Dr. Dewey McLean In 1981, however, Dr. Dewey McLean of Virginia Tech showed how Deccan of Virginia Tech showed how Deccan Traps volcanism in India could have Traps volcanism in India could have increased CO2 levels in the increased CO2 levels in the atmosphere causing a severe global atmosphere causing a severe global warming event. warming event.

(McLean, 1981)(McLean, 1981)• Dr. McLean also showed that the Dr. McLean also showed that the

asteroid theory did not explain all of asteroid theory did not explain all of the evidence found in the geologic and the evidence found in the geologic and biologic record at the KT boundary.biologic record at the KT boundary.

(McLean, 1991)(McLean, 1991)

• For decades now, these two For decades now, these two hypotheses have battled for top hypotheses have battled for top contender in the Great KT Extinction contender in the Great KT Extinction Debate, and yet, neither has been Debate, and yet, neither has been chosen as the champion. chosen as the champion.

•This presentation will attempt to This presentation will attempt to show that this is because it was show that this is because it was neitherneither an asteroid an asteroid nornor the Deccan the Deccan Traps that caused the extinctions Traps that caused the extinctions of 65 million years ago.of 65 million years ago.

• In 1996, a new hypothesis was introduced In 1996, a new hypothesis was introduced that almost seemed to go unnoticed in the that almost seemed to go unnoticed in the KT Extinction Debate. KT Extinction Debate.

• In their book, “The Great Dinosaur In their book, “The Great Dinosaur Extinction Controversy”, Dr. Charles Extinction Controversy”, Dr. Charles Officer and Jake Page showed that most of Officer and Jake Page showed that most of the evidence being used in the asteroid the evidence being used in the asteroid hypothesis could also be volcanic in hypothesis could also be volcanic in nature.nature.

• They also pointed out that not only were They also pointed out that not only were the Deccan Traps occurring at the KT the Deccan Traps occurring at the KT boundary, but that massive volcanism was boundary, but that massive volcanism was occurring all over the world at that time. occurring all over the world at that time.

• (Officer and Page, 1996)(Officer and Page, 1996)

•Particularly, Particularly, large magmatic large magmatic events were events were occurring within occurring within North America North America that was not only that was not only coeval with the coeval with the Extinctions, but Extinctions, but also, with the also, with the uplifting of the uplifting of the Laramide Laramide Orogeny and the Orogeny and the disappearance of disappearance of the Western the Western Interior Seaway.Interior Seaway.

• However, as no However, as no exactexact mechanism mechanism had been found to account for the had been found to account for the exotic mix of materials in the KT exotic mix of materials in the KT boundary layer, this hypothesis was boundary layer, this hypothesis was largely dismissed in the KT Extinction largely dismissed in the KT Extinction Debate.Debate.

•So, I wanted to know what So, I wanted to know what DID DID cause the uplifting of the Rocky cause the uplifting of the Rocky Mountains, as well as the Mountains, as well as the disappearance of the Western disappearance of the Western Interior Seaway, along with massive Interior Seaway, along with massive volcanism, to occur in North America volcanism, to occur in North America at the KT boundary? at the KT boundary? • I began to look at the Geologic I began to look at the Geologic formations of Western North formations of Western North America at the Cretaceous-Tertiary America at the Cretaceous-Tertiary Boundary and the tectonic events Boundary and the tectonic events that created them.that created them.

The Western Interior The Western Interior SeawaySeaway

• Before the beginning of the Laramide, Before the beginning of the Laramide, Texas lay at the bottom of a shallow Texas lay at the bottom of a shallow seaway that stretched across the interior seaway that stretched across the interior from the Arctic Ocean to the Gulf of from the Arctic Ocean to the Gulf of Mexico. This cold, salty sea is known as Mexico. This cold, salty sea is known as the Western Interior Seaway.the Western Interior Seaway.

• Before the Laramide, bays and estuaries Before the Laramide, bays and estuaries covered most of New Mexico (Chronic, covered most of New Mexico (Chronic, 1987); and Arizona lay along the 1987); and Arizona lay along the floodplains of that ancient sea. (Chronic, floodplains of that ancient sea. (Chronic, 1983) 1983)

•Most of the Most of the fossils found at fossils found at the KT the KT boundary in boundary in North America North America were animals were animals that lived that lived within, or within, or along the along the shores of, the shores of, the Western Western Interior Interior Seaway.Seaway.

North America in the Age of the Dinosaurs, 75 mya. (National Geographic,January, 1993)

• Officer and Page (1996) showed that the Officer and Page (1996) showed that the Western Interior Seaway began to disappear Western Interior Seaway began to disappear in the Albian and was mostly gone by the in the Albian and was mostly gone by the Maastrichtian, before 65 mya, caused by the Maastrichtian, before 65 mya, caused by the uplifting of western North America.uplifting of western North America.

• meaning that critical habitats, and indeed, meaning that critical habitats, and indeed, entire biospheres had disappeared entire biospheres had disappeared beforebefore the the KT boundary.KT boundary.

• JD Archibald, has pointed out that 75% of our JD Archibald, has pointed out that 75% of our knowledge of dinosaurs immediately before knowledge of dinosaurs immediately before the KT boundary comes from within the the KT boundary comes from within the Western Interior of North America. (Archibald, Western Interior of North America. (Archibald, 1997)1997)

The Laramide OrogenyThe Laramide Orogeny • The Laramide Orogeny, or uplifting of The Laramide Orogeny, or uplifting of

the Rocky Mountains, began within the Rocky Mountains, began within the interior of the continent at ~80 the interior of the continent at ~80 mya and lasted until ~50 mya. mya and lasted until ~50 mya.

• However, many major thrusting However, many major thrusting events occurred directly at the 65 my events occurred directly at the 65 my boundary.boundary.

• Laramide magmatic trend dated between Laramide magmatic trend dated between 64 and 69 mya. (Officer and Page, 1996)64 and 69 mya. (Officer and Page, 1996)

• The Black Hills, along with the rest of The Black Hills, along with the rest of Wyoming and Montana, weas uplifted Wyoming and Montana, weas uplifted between 72 and 58 mya.between 72 and 58 mya.

• New evidence shows that the Kaibab New evidence shows that the Kaibab plateau, which was uplifted along with the plateau, which was uplifted along with the rest of the larger Colorado plateau, had rest of the larger Colorado plateau, had uplifted as early as 65 mya. (National uplifted as early as 65 mya. (National Geographic, 2007) Geographic, 2007)

• Carlsbad Caverns in New Mexico was Carlsbad Caverns in New Mexico was formed within the limestone of an ancient formed within the limestone of an ancient coral reef that was uplifted at the KT coral reef that was uplifted at the KT boundary and filled with sulfuric acid (H2O boundary and filled with sulfuric acid (H2O + sulfur) that ate away the limestone. The + sulfur) that ate away the limestone. The formation of the caverns themselves began formation of the caverns themselves began ~60 mya. (National Park Service, 2006)~60 mya. (National Park Service, 2006)

• And in Texas, we find the actual edge And in Texas, we find the actual edge of the continent, or of the continent, or CretaceousCretaceous shelf. shelf. The Balcones Escarpment was uplifted The Balcones Escarpment was uplifted at the KT boundary, along with the rest at the KT boundary, along with the rest of western North America.of western North America.

• From the Balcones fault to the Gulf From the Balcones fault to the Gulf Coast, at least one-third of Texas sits Coast, at least one-third of Texas sits upon upon TertiaryTertiary or younger sediments or younger sediments that were deposited as the Rocky that were deposited as the Rocky Mountains uplifted to the west and the Mountains uplifted to the west and the sediments drained into the Gulf. sediments drained into the Gulf. (Chronic, 1987) (Chronic, 1987)

So then, I wanted to know what So then, I wanted to know what exactly caused the Laramide exactly caused the Laramide

Orogeny?Orogeny?• The Laramide had its beginnings The Laramide had its beginnings

within the interior at ~80 mya.within the interior at ~80 mya.

• This age would just happen to This age would just happen to coincide with the formation of the coincide with the formation of the Sierra Nevada batholith on the west Sierra Nevada batholith on the west coast, as the magma beneath this coast, as the magma beneath this arc stopped melting and solidified arc stopped melting and solidified into granite. into granite.

Many scientists today Many scientists today believe that the believe that the Laramide was caused Laramide was caused by the flat-slab by the flat-slab subduction of the subduction of the Farallon plate.Farallon plate.

However, remnants of However, remnants of the Farallon are still the Farallon are still subducting beneath subducting beneath North America, and as North America, and as far as we can tell, they far as we can tell, they are not flat.are not flat.

So then, what caused So then, what caused the slab to go flat at the slab to go flat at the KT boundary?the KT boundary?

(Oceanography, 4(Oceanography, 4thth ed., Garrison) ed., Garrison)

• One study shows that "Subduction of an One study shows that "Subduction of an oceanic plateau about 85-65 Ma oceanic plateau about 85-65 Ma (remnants in the (remnants in the FranciscanFranciscan) produced ) produced east-vergent tectonic wedging in the east-vergent tectonic wedging in the Coast Ranges, possible thrusting along Coast Ranges, possible thrusting along the eastern Sierra Nevada Batholith the eastern Sierra Nevada Batholith margin, and development of Rocky margin, and development of Rocky Mountain Laramide structures.  The Mountain Laramide structures.  The ‘Laramide Orogeny’ is herein redefined ‘Laramide Orogeny’ is herein redefined to include all Late Cretaceous-early to include all Late Cretaceous-early Tertiary (75-45 Ma) fold thrust structures Tertiary (75-45 Ma) fold thrust structures from the Pacific Coast to the Rocky from the Pacific Coast to the Rocky Mountains.“Mountains.“

(Moores, Wakabayashi, and Unruh, (Moores, Wakabayashi, and Unruh, 2003)2003)

It is within the It is within the Franciscan Franciscan melange that melange that we find our we find our clues to what clues to what really really happened at happened at the KT the KT boundary.boundary.On the west On the west coast of North coast of North America, America, we can still we can still see the scar.see the scar.

(Scripps (Scripps Institute of Institute of OceanographOceanography)y)

The Coast Range Ophiolite represents a piece The Coast Range Ophiolite represents a piece of Jurassic age oceanic crust that was of Jurassic age oceanic crust that was uplifted onto the North American continent.uplifted onto the North American continent.

The Great Valley Sequence represents the The Great Valley Sequence represents the sediments that were deposited on that ocean sediments that were deposited on that ocean floor while it still lay within the ocean.floor while it still lay within the ocean.

Structurally, the Franciscan lies beneath the Structurally, the Franciscan lies beneath the Coast Range Ophiolite and Great Valley Coast Range Ophiolite and Great Valley Sequence in California. Sequence in California.

The Franciscan is a melange, or mixture of The Franciscan is a melange, or mixture of differing materials: greywacke, greenstone, differing materials: greywacke, greenstone, chert, and serpentinite. chert, and serpentinite.

USGSUSGSProfessional Professional Paper 1515, Paper 1515, TheTheSanAndreasSanAndreasFault.Fault.

Geologic sketch Geologic sketch map of map of California,California,

Based on U.S. Based on U.S. Geological Geological Survey (1966), Survey (1966), Jennings and Jennings and others (1970), others (1970), and Ross (1984). and Ross (1984).

One study shows that one sandstone One study shows that one sandstone sequence found within the sequence found within the Franciscan is volcanic in nature and Franciscan is volcanic in nature and “concluded that these rocks were “concluded that these rocks were deposited on the flank of deposited on the flank of an oceanic an oceanic rise or plateaurise or plateau….”….”

This study also showed that the This study also showed that the sandstone is similar in chemistry to sandstone is similar in chemistry to the Greenstones found in the the Greenstones found in the Permanente terrane of California.Permanente terrane of California.

(Larue and Sampayo, 1990)(Larue and Sampayo, 1990)

Greywacke

GreenstoneGreenstone

The Greenstone found within the The Greenstone found within the Franciscan is…”an altered oceanic Franciscan is…”an altered oceanic pillow basalt believed to have been pillow basalt believed to have been formed during the Jurassic and formed during the Jurassic and Cretaceous far out in the Pacific Cretaceous far out in the Pacific along a spreading oceanic ridge.”along a spreading oceanic ridge.”

(Mount Diablo Interpretive (Mount Diablo Interpretive Association)Association)

• One study shows that the cherts One study shows that the cherts found within the Franciscan are found within the Franciscan are manganiferous,manganiferous,

and were also formed on the flanks and were also formed on the flanks of a mid-ocean ridge. (Crerar, 1982)of a mid-ocean ridge. (Crerar, 1982)

• Manganese is known to emanate Manganese is known to emanate from hydrothermal vents along mid-from hydrothermal vents along mid-ocean ridges today.ocean ridges today.

Manganiferous Cherts

The Caleras limestoneThe Caleras limestone

““Jenkyns 1980), Sliter (1984), and Jenkyns 1980), Sliter (1984), and Tarduno, et al., argues that the Tarduno, et al., argues that the Caleras limestone was deposited on Caleras limestone was deposited on top of an oceanic rise or plateau top of an oceanic rise or plateau during the Late Cretaceous and was during the Late Cretaceous and was subsequently transported NE until it subsequently transported NE until it was accreted to the North American was accreted to the North American continental margin about 65 mya.” continental margin about 65 mya.”

((inin Larue and Sampayo, 1990) Larue and Sampayo, 1990)

• One study shows One study shows that a Jurassic age that a Jurassic age hydrothermal vent hydrothermal vent community has community has been found within been found within the Franciscan, the Franciscan, similar to those similar to those found around the found around the Galapagos Islands Galapagos Islands today.today.

(Little, Danelian, (Little, Danelian, Herrington and Herrington and Haymon, 2004)Haymon, 2004)

• The Franciscan, then, would seem to The Franciscan, then, would seem to show all of the evidences of being a show all of the evidences of being a mid-ocean ridge AND associated mid-ocean ridge AND associated ocean-island plateau (hotspot), ocean-island plateau (hotspot), similar to today’s Galapagos Islands.similar to today’s Galapagos Islands.

• But if the Franciscan does indeed But if the Franciscan does indeed represent an oceanic plateau and represent an oceanic plateau and mid-ocean ridge segment, WHEN, mid-ocean ridge segment, WHEN, exactly did it subduct beneath North exactly did it subduct beneath North America?America?

The Great Valley Sequence that lay on The Great Valley Sequence that lay on top of the Coast Range Ophiolite has top of the Coast Range Ophiolite has been dated from ~140-65 mya. been dated from ~140-65 mya.

• Meaning that these sediments had Meaning that these sediments had been accumulating for ~75 my.been accumulating for ~75 my.

• But by 65 mya, the GVS had been But by 65 mya, the GVS had been uplifted and was subject to erosion. uplifted and was subject to erosion. (Mount Diablo)(Mount Diablo)

• Major Franciscan uplift ca. 65 mya, Major Franciscan uplift ca. 65 mya, coeval with graben formation within coeval with graben formation within the CRO, at the KT Boundary the CRO, at the KT Boundary

(Moxon and Grahamm, 1987; Unruh, (Moxon and Grahamm, 1987; Unruh, Dumitru and Sawyer, 2007)Dumitru and Sawyer, 2007)

• Coast Range Thrust/Great Coast Range Thrust/Great Unconformity- 65 mya (Moores)Unconformity- 65 mya (Moores)

• Franciscan cooling ages ~61 mya Franciscan cooling ages ~61 mya (Unruh, et al., 2007)(Unruh, et al., 2007)

• Los Angeles, Santa Barbara and Los Angeles, Santa Barbara and Ventura all sit on top of thick Ventura all sit on top of thick Cretaceous-Tertiary sediments. Cretaceous-Tertiary sediments. (USGS Prof. Paper 1515)(USGS Prof. Paper 1515)

• Wakabayashi Wakabayashi showed that the showed that the Salinian block Salinian block collided with the collided with the Franciscan ~60-Franciscan ~60-50 mya. 50 mya. (Wakabayashi, (Wakabayashi, 1988)1988)

• Vedder, Howell Vedder, Howell and McLean and McLean (1983) shows (1983) shows that thrusting on that thrusting on the Salinian the Salinian occurred from occurred from 65-55 mya. 65-55 mya.

• As the Salinian block collided with As the Salinian block collided with the Franciscan, the MOR/hotspot the Franciscan, the MOR/hotspot would have been trapped within a would have been trapped within a backarc basin between the Salinian backarc basin between the Salinian block on the west and the subduction block on the west and the subduction zone/Coast Range Ophiolite/Sierra zone/Coast Range Ophiolite/Sierra Nevada on the east. Nevada on the east.

• As the hotspot/MOR moved was As the hotspot/MOR moved was thrust beneath the continent, it thrust beneath the continent, it would move in beneath the would move in beneath the downgoing plate, thereby causing downgoing plate, thereby causing the flat-slab subduction that moved the flat-slab subduction that moved the Laramide into the Interior.the Laramide into the Interior.

This event is what caused the Coast This event is what caused the Coast Range Thrust on the west coast, the Range Thrust on the west coast, the uplifting of the western half of North uplifting of the western half of North America continent, as well as the America continent, as well as the disappearance of the Western Interior disappearance of the Western Interior Seaway, at the Cretaceous-Tertiary Seaway, at the Cretaceous-Tertiary boundary.boundary.

The current presentation will suggest The current presentation will suggest that this event also caused the that this event also caused the deposition of the KT boundary layer, as deposition of the KT boundary layer, as well as the extinction of the dinosaurs, well as the extinction of the dinosaurs, 65 mya.65 mya.

All of the materials being used to All of the materials being used to describe the asteroid, can also be describe the asteroid, can also be explained by the closing off of a mid-explained by the closing off of a mid-ocean ridge and/or ocean island ocean ridge and/or ocean island hotspot. hotspot.

• IridiumIridium

• Glass spherulesGlass spherules

• Shocked quartzShocked quartz

• GraniteGranite

• AndesiteAndesite

IridiumIridium

• Member of the platinum group with Member of the platinum group with platinum, osmium and rheniumplatinum, osmium and rhenium

• Denser than iron or nickel, therefore, Denser than iron or nickel, therefore, would sink to the bottom of the would sink to the bottom of the mantle (ie.mantle/core boundary)mantle (ie.mantle/core boundary)

• Brought to the surface by certain Brought to the surface by certain types of volcanic eruptions (mantle types of volcanic eruptions (mantle plumes)plumes)

• One study shows that rare OsIrRu minerals have One study shows that rare OsIrRu minerals have been found uplifted in the Josephine Ophiolite of been found uplifted in the Josephine Ophiolite of Oregon and northern California.Oregon and northern California.

• The authors of this study show that “…an The authors of this study show that “…an ancient platinum group element reservoir with a ancient platinum group element reservoir with a supra-chondritic Pt/Os… exists within the supra-chondritic Pt/Os… exists within the mantle. (Meibom and Frei, 2002). And also, that mantle. (Meibom and Frei, 2002). And also, that the rare OsIrRu grains were “…transported from the rare OsIrRu grains were “…transported from the core-mantle boundary region to the the core-mantle boundary region to the lithosphere as xenoliths in a mantle lithosphere as xenoliths in a mantle plume/convection system.”plume/convection system.”

(Bird, Meibom, and Frei, and Nagler, 2002) (Bird, Meibom, and Frei, and Nagler, 2002)

The Josephine ophiolite is related to the Coast The Josephine ophiolite is related to the Coast Range Ophiolite, and was uplifted along with it Range Ophiolite, and was uplifted along with it at the KT boundary. at the KT boundary.

Glass SpherulesGlass Spherules

• Glass spherules can also be created by Glass spherules can also be created by volcanic processes as magma comes volcanic processes as magma comes into contact with water. The magma into contact with water. The magma cools rapidly on contact, creating the cools rapidly on contact, creating the spherules.spherules.

The ocean floors surrounding seamounts The ocean floors surrounding seamounts are often littered with glass spherules.are often littered with glass spherules.

• Within the Franciscan, the Stonyford Within the Franciscan, the Stonyford volcanic complex is an ancient volcanic complex is an ancient seamount that was accreted onto seamount that was accreted onto California. It is surrounded by glass California. It is surrounded by glass spherules.spherules.

• One study shows that the glass One study shows that the glass spherules found within the KT spherules found within the KT boundary layer are altered oceanic boundary layer are altered oceanic basalt. This is why it is believed that basalt. This is why it is believed that the asteroid must have hit within an the asteroid must have hit within an oceanic basin. oceanic basin.

• (Montanari, Hay, Alvarez, Alvarez, (Montanari, Hay, Alvarez, Alvarez, Asaro, Michel, and Smit, 1983) Asaro, Michel, and Smit, 1983)

• This study also shows that the This study also shows that the spheroids are K-feldspar and pyrite, spheroids are K-feldspar and pyrite, which is also found on the west which is also found on the west coast.coast.

““Shocked” quartzShocked” quartz

• Shocked quartz can also be created Shocked quartz can also be created by geologic processes. by geologic processes.

• Also found in uplifted ophiolites.Also found in uplifted ophiolites.

• The greywacke of the Franciscan The greywacke of the Franciscan consists of abundant angular quartz.consists of abundant angular quartz.

• Deformation lamellae is present in Deformation lamellae is present in quartz grains within the Franciscan. quartz grains within the Franciscan. (Schemann, Unruh and Moores, (Schemann, Unruh and Moores, 2008)2008)

• Miller shows that at Miller shows that at 67 mya67 mya, sea , sea levels dropped dramatically, but that levels dropped dramatically, but that by 65 mya, sea levels had returned by 65 mya, sea levels had returned to near normal. to near normal.

• ( Miller, 2003)( Miller, 2003)

• Between 67 and 65 mya, oxygen levels Between 67 and 65 mya, oxygen levels dropped from 35 parts per million to 27 ppm dropped from 35 parts per million to 27 ppm (Dowswell, )(Dowswell, )

• Dr. Gerta Keller showed that foraminefera Dr. Gerta Keller showed that foraminefera began disappearing from the record 500,000 began disappearing from the record 500,000 years before the KT boundary. (Keller, 2000 )years before the KT boundary. (Keller, 2000 )

• In the oceans, high levels of CO2 cause In the oceans, high levels of CO2 cause calcium-bodied plankton to dissolve at depths calcium-bodied plankton to dissolve at depths of greater than 4500 ft below sea level. of greater than 4500 ft below sea level.

• This could show that CO2 was increasing in This could show that CO2 was increasing in the ocean waters at the same time that the ocean waters at the same time that oxygen levels were decreasing in the oxygen levels were decreasing in the atmosphere, atmosphere, beforebefore the KT boundary. the KT boundary.

• Zoller studied the fine particle emissions Zoller studied the fine particle emissions of the Kilauea eruption of 1983 and found of the Kilauea eruption of 1983 and found high levels of Iridium, as well as high high levels of Iridium, as well as high levels of selenium, arsenic, and fluoride. levels of selenium, arsenic, and fluoride. The presence of fluoride lead these The presence of fluoride lead these authors to believe that the Iridium was authors to believe that the Iridium was released as Iridium hexafluoride. (Zoller, released as Iridium hexafluoride. (Zoller, 1983)1983)

• The high levels of selenium could provide The high levels of selenium could provide a clue as high levels of selenium have a clue as high levels of selenium have also been found in dinosaur eggshells at also been found in dinosaur eggshells at the KT boundary.the KT boundary.

The Real Killer?The Real Killer?

• If the iridium was separated from the If the iridium was separated from the hexafluoride…….Hexafluoride hexafluoride…….Hexafluoride combines with Selenium to become a combines with Selenium to become a poisonous gas, poisonous gas, Selenium hexafluorideSelenium hexafluoride; ; which causes severe skin irritation, which causes severe skin irritation, breathing difficulties and respiratory breathing difficulties and respiratory failure leading to death.failure leading to death.

• Dinosaur skeletons have been found Dinosaur skeletons have been found at the KT boundary with arched backs at the KT boundary with arched backs as if they were convulsing from as if they were convulsing from poisoning or asphyxiation.poisoning or asphyxiation.

• High levels of High levels of selenium are still selenium are still found today in KT found today in KT boundary soils.boundary soils.

• This map shows This map shows where seleniferous where seleniferous plants in North plants in North America today are America today are still causing still causing trouble for cattle trouble for cattle and other wildlife.and other wildlife.

• Open dots-50-500 Open dots-50-500 ppm seleniumppm selenium

• Black dots-more than Black dots-more than 500 ppm selenium500 ppm selenium

• (Rosenfeld and Beath, (Rosenfeld and Beath, 1964, 1964, In In Officer and Officer and Page, 1996.)Page, 1996.)

Chixculub craterChixculub crater

• Dr. Charles Officer, along with many Dr. Charles Officer, along with many others, spent years trying to prove others, spent years trying to prove that the Chixculub crater was a that the Chixculub crater was a volcanic structure. volcanic structure.

• I will not argue here whether the I will not argue here whether the Chixculub represents an asteroid Chixculub represents an asteroid crater or not. crater or not.

But, IF an asteroid did strike the Gulf But, IF an asteroid did strike the Gulf at 65 mya, it did NOT causeat 65 mya, it did NOT cause : :

• the uplifting of the entire ocean floor on the uplifting of the entire ocean floor on the west coast, the west coast,

• the uplifting of the western half of the the uplifting of the western half of the North American continent; North American continent;

• the disappearance of the Western Interior the disappearance of the Western Interior Seaway; Seaway;

• the change in oxygen/CO2 levels; the change in oxygen/CO2 levels; • the drop in sea levels; the drop in sea levels; • the volcanism that was occurring the volcanism that was occurring

throughout the world at that time;throughout the world at that time;• OR the Extinctions that were already OR the Extinctions that were already

occurring hundreds of thousands of years occurring hundreds of thousands of years before it hit.before it hit.

•The evidence presented The evidence presented herein will hopefully show herein will hopefully show that it was the subduction of that it was the subduction of a mid-ocean ridge and a mid-ocean ridge and ocean island plateau on the ocean island plateau on the west coast of North America west coast of North America that DID, 65 million years that DID, 65 million years ago.ago.