<\/p>\n
\u00a0\u00a0\u00a0\u00a0\u00a0Let me be the first to admit that the above title isn\u2019t exactly something designed to give you a warm and fuzzy feeling.\u00a0 It is a commonly held belief that the end of the dinosaur\u2019s rule was the only time the Earth has undergone a mass sterilization of living things.\u00a0 The added \u2018(s)\u2019 is necessary because author Peter Brannen\u2019s 2017 book <\/span>The Ends of the World – Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth\u2019s Past Mass Extinctions <\/span><\/i>(Harper Collins Books) points out the dinosaurs met their end in what would have been only the most <\/span>recent<\/span><\/i> mass extinction event.\u00a0 Brannen dug into the past and found throughout the eons of our planet\u2019s history, there have been multiple times when various climatic and geological events have wiped the slate clean.\u00a0 That is the bad news.\u00a0 The good news is that our little corner of the universe seems to be quite resilient when it comes to rebounding after such cataclysmic events.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0This <\/span>FTV <\/span><\/i>will not attempt to cover all of the episodes of mass extinctions Brannen covers because it would require me to reproduce the entire book.\u00a0 I was able to obtain a copy via Inter-Library loan from the Ontonagon Township Library after Todd at the WOAS-FM West Coast Bureau recommended it.\u00a0 If one has an interest in the entire story of these multiple mass extinction events, let me suggest you ask your friendly librarian to find Brannen\u2019s book for you.\u00a0 We are going to narrow the focus here down to the aforementioned \u2018dino killer\u2019 event.\u00a0 Why?\u00a0 Even though this is probably one of the best known theories, geologists are still not in total agreement as to what exactly happened.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0If the phrase \u2018geologists are not in total agreement\u2019 brings up a mental image of bespeckled men in white lab coats duking it out, let me punch some holes in that old stereotypical view of what a geologist (or any scientist) looks like.\u00a0 On one side of the \u2018what did in the dinosaurs\u2019 argument is a tenured geologist from Princeton named Gerta Keller.\u00a0 Keller did not come to the profession in any sort of usual way.\u00a0 She was born to a rural Swiss farm family.\u00a0 Brannen describes her as, \u201cThe youngest of twelve children and the black sheep of the family who repeatedly had her future ambitions thwarted.\u00a0 The first snub came as a teenager from a shrink who told her to abandon her hopes of becoming a doctor (because she came from too meager a background for such daydreams).\u201d\u00a0 She fled the drudgery of an apprenticeship as a dressmaker and set off to see the world by hitchhiking across North Africa and the Middle East.\u00a0 \u201cI\u2019m a strange bird,\u201d she admitted to Brannen.\u00a0 Sounds like she took a gap year before they were in vogue.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Her story would be offbeat enough as is, but it took a turn toward \u2018stranger yet\u2019 when she was preparing to take a trip on the trans-Siberian railroad.\u00a0 While she was taking care of a fellow traveler who became ill, she herself ended up \u2018deathly ill\u2019:\u00a0 \u201cI got so sick I took a train to the Vienna hospital, where they thought it was a miracle still to be alive.\u00a0 I was isolated for six weeks on intravenous before checking myself out of the hospital.\u00a0 I have a habit of doing that.\u201d<\/span><\/p>\n Her next episode off the beaten path took her to Australia:\u00a0 \u201cI got shot in a bank robbery.\u00a0 I was pronounced dead.\u201d\u00a0 Brannen says, \u201cThe bullet passed between her heart and spine, pierced her lungs, and shattered her ribs on the other side.\u201d\u00a0 Brannen later describes Keller as having a \u2018stubborn streak\u2019.\u00a0 Did she become this way after all of this or was it part of it the reason why she refused to go quietly into the great beyond?<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0For some reason, Gerta had always thought she would die at the age of twenty-three.\u00a0 After getting shot at age twenty-two, she decided perhaps living longer wasn\u2019t a bad option.\u00a0 She continued her story:\u00a0 \u201cThe entire blue sky was essentially a film of my life going by, and by the time I got to the end I said, \u2018I don\u2019t want to die,\u2019 and that was it.\u00a0 I had this weird experience where I came to, and I was floating over Sydney.\u00a0 It was very peaceful.\u00a0 Then there was this ambulance and siren breaking the peace, making a big racket.\u00a0 I heard this woman scream and calling for her momma and I got really annoyed.\u00a0 I thought, \u2018Jeez, I would never do that\u2019.\u00a0 All of a sudden I was sucked down and I was the woman screaming, and there were two orderlies holding me down.\u201d\u00a0 Brannen asked if she may have been hallucinating.\u00a0 Gerta said she later visited places she had seen in her Sydney fly by – places she had never been to before she was shot – and they were just as she remembered them.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0After she recovered, Keller found herself living in a ghetto in San Francisco.\u00a0 Her academic life began as an adult high school student before she landed at San Francisco State long before she joined the Princeton faculty.\u00a0 Now that we have dispelled any notions you may have had about the stereotypical science nerd, we will set Gerta Keller aside for a few moments and get back to dinosaur extinction.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0The causes for the end of the dinosaur\u2019s reign has been debated ever since their bones were first dug up.\u00a0 Cartoonist Gary Larson\u2019s <\/span>The Far Side<\/span><\/i> cartoons ventured various humorous ideas by showing dinosaurs smoking or arriving too late to board Noah\u2019s Ark.\u00a0 Some theories were dismissed out of hand (and not very humorously) while others were tossed into the growing pool of ideas to sink or swim.\u00a0 The most widely accepted theory (the Alvarez Asteroid Impact Hypothesis) was first put forth by the father-son team of Luiz and Walter Alvarez.\u00a0 They were studying layers of clay found at what is known as the Cretaceous-Paleogene (K-PG or more popularly, the K-T) Boundary in Gubbio, Italy.\u00a0 Upon finding a layer of iridium embedded in the boundary layers before the dinosaurs went extinct, they reasoned they had been killed off by a massive asteroid strike.\u00a0 Iridium is rare on the Earth but commonly found in asteroids.\u00a0 The world-wide distribution of this iridium rich layer led to their Asteroid Impact Hypothesis.\u00a0 Naturally, the theory was greeted with skepticism and cries of, \u201cOkay, show us the impact site and we will (maybe) believe you.\u201d It remained controversial as long as they couldn\u2019t find the smoking gun (or crater, in this case).<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Here is a highly condensed version of what came next:\u00a0 The massive 110 mile diameter Chicxulub crater was discovered on the northeast coast of the Yucatan Peninsula in Mexico.\u00a0 The full story of the discovery can be found in Alvarez\u2019s book <\/span>T. rex and the Crater of Doom <\/span><\/i>(1997).\u00a0 The impacting object was traveling so fast and was massive enough to punch through the Earth\u2019s atmosphere and straight through the crust to the mantle below.\u00a0 Some of the material dislodged by the asteroid strike was hurled into space while the rest would have taken suborbital paths like a flock of ICBMs to the far reaches of the horizon.\u00a0 Theories on how high the temperatures rose in the atmosphere, how much damage the shockwave would have done, and how widely the tsunami created would have carried debris inland were tossed about.\u00a0 The details of such a strike are chilling, indeed, and one wonders how any life would have survived this hellish version of Earth.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Critics (of the Alvarez theory) pointed to a 62-mile-wide crater in Manicouagan, Quebec which is easily visible from the International Space Station.\u00a0 Some geologists pondered,\u00a0 \u201cWhy\u00a0 was there not a similar extinction event associated with a strike nearly as large as the Chicxulub impact?\u201d\u00a0 Others, like Gerta Keller, simply pointed out inconsistencies in the \u2018global annihilation by an asteroid strike\u2019 theory.\u00a0 For example, the oxygen requirements of the global firestorm set off by the rain of asteroid ejecta doesn\u2019t add up.\u00a0 Brennan interpreted the evidence of the asteroid strike as a killing mechanism as, \u201cDubious.\u201d\u00a0 \u201cClaims that the atmosphere was temporarily heated to the temperature of a pizza oven have long been viewed with skepticism by biologists,\u201d is how Keller stated it.\u00a0 She favors an extinction event more aligned with global volcanism which puts her at odds with those leaning heavily toward the Asteroid Impact Hypothesis.\u00a0 The discussions from these opposite ends of this \u2018who done it\u2019 mystery have been, at times, heated.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Theories are ideas, however, and not always carved in stone.\u00a0 As new data is collected and new eyes are focused on the questions raised by supporters and skeptics, theories evolve.\u00a0 One of the things that haunted both the \u2018asteroid vs volcanism\u2019 theories was the time line.\u00a0 How close did the event occur to the actual extinction event?\u00a0 Drilling cores collected from deep layers of ancient ocean sediments and lava flows slowly began to narrow this gap.\u00a0 Whatever cataclysmic event caused the extinctions reflected in the K-T boundary rock layers caused further tweaks in both the Alvarez and Keller theories.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Keller\u2019s volcanic hypothesis focused on an area in India known as the Deccan Traps.\u00a0 As the Indian subcontinent separated from the supercontinent known as Gondwana, it moved across a hotspot in the Earth\u2019s mantle.\u00a0 Known as the \u2018Reunion Hotspot\u2019 (the volcanic island of Reunion is currently sitting on top of this stationary lava source), it traces an arc of islands by it that includes the Maldives, the Seychelles, and Mauritius.\u00a0 This island arc is very similar to the one that created the Hawaiian Island chain as continental drift moved that part of the Pacific Ocean crustal plate over another hotspot.\u00a0 When India itself passed over the Reunion Hotspot, it created lava flows (in some areas they are two miles thick) known as the Deccan Traps.\u00a0\u00a0<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0Geologists studying the Deccan Traps deposits in India\u2019s western Mahabaleshwar district noticed something interesting as they sampled the layers making up these 11,500 foot tall mountains.\u00a0 The lower deposits show a great deal of fracturing and a chemical mix consistent with molten rock moving slowly toward the surface.\u00a0 This gave the magma time to melt the crustal rock and absorb the minerals into the lavas.\u00a0 The upper layers, however, were not fractured and do not display the mix of crustal elements found at greater depths.\u00a0 It looks as though a great amount of material gushed from the Earth\u2019s mantle from the Reunion Hotspot. The later Deccan Flows were formed much faster than the earlier, lower layers.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0UC Berkeley geologist Mark Richards has always favored the Alvarez camp.\u00a0 At an annual meeting of the Geological Society of America, he was scheduled to speak after Keller\u2019s presentation.\u00a0 Richards\u2019 talk was expected to be a rebuttal of the \u2018Deccan deposit volcanism vs the Asteroid Impact Hypothesis\u2019 address.\u00a0 Surprisingly, he began by acknowledging the topic as, \u201cThe 80 pound gorilla in the room that has turned into an 8,000 pound gorilla, in my view.\u201d\u00a0 He went on to explain that new data shows the Chicxalub impact and the accretion of the Deccan Traps lava flows was just too close together for him to feel comfortable giving one or the other credit for being the mechanism that killed the dinosaurs.\u00a0 As he told the GSA gathering, \u201cThe chances of these [the impact and the lava flows] occurring at random seem to either imply some sort of casual effect or some kind of divine intervention.\u00a0 And since I am no expert on the latter – I am a geophysicist – I\u2019m going to concentrate on what may have been considered an outrageous hypothesis a couple of years ago, which I no longer think is such an outrageous idea.\u201d<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Richards was inspired to reexamine his views by a middle of the night epiphany he had after visiting the Mayan ruins of Chichen Itza in the Yucatan Peninsula.\u00a0 He suddenly remembered reading about a theory that earthquakes have been proven to cause volcanic eruptions.\u00a0 Data collected had all but verified that the stronger an earthquake was, the further away it could cause increased volcanism.\u00a0 The estimated strength of the ground disturbance caused by the Chicxulub impact was an earthquake with an unbelievable magnitude of 11.\u00a0 Extrapolating this data from volcanic activity stimulated by earthquakes of a smaller magnitude, he decided that the dinosaur killing event was actually caused by a \u2018one-two\u2019 punch.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Yes, the asteroid impact hurled a massive amount of material into space and into the atmosphere.\u00a0 It also triggered a surge of volcanism from the already erupting Deccan Traps that, \u201cWas like a fire hose right out of the mantle,\u201d according to Richards.\u00a0 When Alvarez himself read Richards\u2019 ideas, he personally called him on a Sunday afternoon and invited him to come over \u2018right now\u2019 to discuss it.\u00a0 Richards and Alvarez concluded, \u201c[The new data] suggested that the Deccan Traps were yawning and maybe saying, \u2018We\u2019re done,\u2019 . . . and then something happened.\u201d\u00a0 The \u2018something\u2019 would have been the Chicxulub asteroid impact.\u00a0 The lower levels of the Deccan Trap flows just happen to rest on top of the K-T extinction boundary.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Richards\u2019 work has begun to bring the two sides closer together but he has avoided blaming the death of the dinosaurs on one or the other (or both) events.\u00a0 \u201cThis has been an acrimonious debate,\u201d he told Brannen, \u201cI\u2019ve been trying to steer clear of that.\u00a0 We\u2019re going to find out in the next couple of years what happened,\u00a0 We might as well just all be friends and find out.\u00a0 Together.\u00a0 This story is only going to get more interesting.\u201d<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0A colleague of Richards named Paul Renne is less reluctant to avoid embracing this new view of the K-T boundary extinction:\u00a0 \u201cI think maybe we are moving away from fireballs and damnation and that sort of thing.\u00a0 It\u2019s been a great mystery for many years.\u00a0 Bigger impacts have shown to be associated with flood basalts like the Deccan Traps – so why is this a bizarre coincidence?\u00a0 It may be that Chicxulub was the gun and the Deccan Traps were the bullet,\u201d Renne said.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0The Lake Superior Basin has a similar history to the Deccan Traps.\u00a0 At one point in our geological history, a series of fissures in our neighborhood pumped out lava flows in a volume never before seen.\u00a0 Unlike the area of India where the Deccan Traps were created, the lava flows created here caused the crust to sag under the weight of the new layers.\u00a0 The Lake Superior Traps are thousands of feet thick and their weight pushed the mantle below the crust down.\u00a0 This sag in the crust directed the advancing continental glaciers of the last Ice Age into the valley created by the sinking crust.\u00a0 When the glaciers melted back, they filled the deep valley gouged out of the Earth and it became (in stages) Lake Superior.\u00a0 Had this volcanic activity occurred around the time of another massive asteroid strike, maybe the Lake Superior region would get the blame for killing off the dinosaurs.<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0For the record, there have been five major extinction events on Earth, including the one that did in the dinosaurs.\u00a0 Some think humans will cause the sixth.\u00a0 Paleontologist Doug Erwin says, \u201cIf we have already started the sixth extinction, buy a case of Scotch because nothing will reverse it.\u00a0 I think if we keep things up long enough [meaning \u2018human degradation of the Earth\u2019s environment], we\u2019ll get to a mass extinction, but we\u2019re not in a mass extinction yet, and I think that\u2019s an optimistic discovery because that means we actually have time to avoid Armageddon.\u201d\u00a0<\/span><\/p>\n \u00a0\u00a0\u00a0\u00a0\u00a0Are we smart enough to not return to burning more coal, stop disavowing the value of wind and solar power, and dismantling the regulatory agencies designed to keep us from reaching such a tipping point?\u00a0 I, for one, sure hope we are.<\/span><\/p>\n Top Piece Video:\u00a0 Weird Al’s take on Jurassic Park seemed appropriate<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" \u00a0\u00a0\u00a0\u00a0\u00a0Let me be the first to admit that the above title isn\u2019t exactly something designed to give you a warm and fuzzy feeling.\u00a0 It is a commonly held belief that the end of the dinosaur\u2019s rule was the only time the Earth has undergone a mass sterilization of living things.\u00a0 The added \u2018(s)\u2019 is […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11,8,9],"tags":[],"class_list":["post-3715","post","type-post","status-publish","format-standard","hentry","category-education","category-from-the-vaults","category-woas"],"_links":{"self":[{"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=\/wp\/v2\/posts\/3715","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3715"}],"version-history":[{"count":3,"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=\/wp\/v2\/posts\/3715\/revisions"}],"predecessor-version":[{"id":3718,"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=\/wp\/v2\/posts\/3715\/revisions\/3718"}],"wp:attachment":[{"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3715"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3715"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.woas-fm.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3715"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}