# Presentation: 681965

## The Dinosaur Extinctions

**The Dinosaur Extinctions**

**Quark Matter 2004**
**Richard A. Muller**
**16 January 2004**

**what is known**
**and what is unknown**

**unknown**

**unknown**

**unknown**

## 1978Luis AlvarezandWalter Alvarezwith Frank Asaro & Helen Michel, analyzed a thin layer of clay, and deduced that an asteroid or comet had killed the dinosaurs. 

## Since then, we’ve learned a lot.         However ...

***Since then, we’ve learned a lot.******         However ...***

***There is a lot more that we don’t know******now, than we didn’t know 25 years ago.***

## 1812:George Cuvierdiscovers extinctionsRock from sediment preserves thehistory of life

**Figure from Cuvier:**** *****Discourse on the Revolutions of the Surface of the Globe***** ****(1812)**

## Slide 5

## Mass

***Mass***
***extinction***

## Slide 7

## impact triggers avalanche

- Mutter LDEO
- graphics

- Earth iridium:
- sunk to the
- core during
- formation

- Asteroid iridium:
- spreads on the
- surface

## Slide 9

- Shocked Quartz

- micro tektites

- 1
- mm

- (courtesy Geological
- survey of Canada)

- (courtesy of Alan Hildebrand)

## Why did itexplode?

**Why did it*****explode*****?**

**The asteroid (or comet) was made of**
**rock and ice**
**(and 3 parts per million of iridium).**

## a little physics:kinetic energy of asteroid/comet

- Kinetic energy = (1/2) m v2
- For v = 30 km/sec = 3 x106 cm/sec
**Kinetic energy per gram** =  (1/2) v2
- = 4 x1012 erg/gm =  4 x105 joule/gm
- = 105 cal/gm = 100 Cal/gm
**= 100 x TNT**

## ShoemakerLevy1994

**1 km comet impact on Jupiter**
**July 18, 1994**
**Velocity ≈ 60 km/sec**
**Energy = 0.004 Cretaceous impact**

## John Dawson dinosaur(Hsu book)

- by John Dawson

**An Art Gallery:**

**Dinosaurs notice the impact**

## runningdinosaur

- by John Dawson

## Goldstein cover

- Don Davis

## dinosaur gasp

## dinosaur dawn

## dinosaur vincent perez

- Vincent Perez

## Time MagazineCover

- Cover art by Braldt Braids

## miscdinosaurs

## dinosaur comet

- Don Davis

## pterosaur view

## dinosaurs little

- Don Davis

## brontosaurus

## dinosaur Alvarez French edition

- S. Numazawa

## Science made stupidTom Weller

- Tom Weller

## non sequitur cartoon

- Wiley & Miller

## dinosaursuperbowl

## Dick Adair cartoon

- Ron Miller

## Whee!

- Don Davis

## Art Gallery II:the impactor was big

**Art Gallery II:****the impactor was big**

## gaspra

**for reference:**
**Gaspra**

**Don’t think “rock.”  Think “mountain.”**

## impact

## impact

- (It wasn’t really *that* big.)

## impact

## Deep Impactposter

##  A question that nagged us from 1978-1991 Where’s the crater?

** ****A question that nagged us from 1978-1991 *****Where’s the crater?***

**Plausible but unsatisfying answer: ****Maybe it was subducted by plate motion.**

## Barringer meteor crater

**Barringer meteor crater**
**in Arizona**

**diameter**
**1 km**

## Manicouagan Crater (Canada)

**Manicouagan Crater (Canada)**

**diameter 45 miles**

## known Earth impact craters

*distribution roughly follows distribution of geologists*

## platetectonics movie

**Was the crater subducted?  Plates move ...**

**continents break, oceans appear, and *****disappear***

**600 Myr**
**to**
**present**

## Surprise!Chicxulub

- 1981: Penfield & Camargo
- 1991: Hildebrand et al.

## Yucatan Penninsula North(NASA Radar Topography Mission)

## Chicxulub gravity image 

- from V.L. Sharpton

## 1984PaleontologistsDavid Raup & Jack SepkoskiExtinctions recur on a very regular schedule.

**1984****Paleontologists****David Raup & Jack Sepkoski****Extinctions recur on a *****very***** regular schedule.**

## Regularly scheduled extinctionsfor the last 250 million years

**Arrows drawn every**
**26 million years**

- D. Raup and J. Sepkoski, 1984

## possible explanations:

-  oscillations up and down in galaxy
-  Planet X
-  Nemesis

**?**

## comet shower

- Jon Lomberg

- (an idea of Jack Hills)

## Nemesis(Time)

## comet showers

- from “Nemesis” 1988 cover

- comet Shoemaker-Levy 1994

## What is now know about the causes of the Raup-Sepkoski extinctions?

**What is now know about the causes of the Raup-Sepkoski extinctions?**

## Extinctions (and other things)for the last 250 million years

**Extinctions (and other things)****for the last 250 million years**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

**65 Myr**
**Cretaceous-Tertiary**

## Iridium Anomalyand mass extinctions

**Iridium Anomaly****and mass extinctions**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## E/O Iridium

**Possible comet shower**
**35 Million years ago**

## Another iridium anomaly

**Another iridium anomaly**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## C/T Iridium

## more iridium anomalies

**more iridium anomalies**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## known Earth craters

## 7 largest known impact craters on Earth

| CRATER NAME | LOCATION | LAT |  | LONG | DIAMETER | AGE 
(Myears) | EXTINCTION |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Chesapeake Bay | Virginia, U.S.A. | N 37 17' | W 76 1' |  | 90 km | 35.5 
± 0.3 | Eocene-Oligocene |
| Acraman | South Australia | S 32 1' | E 135 27' |  | 90 km | ~ 590 | pre-Phanerozic |
| Manicouagan | Quebec, Canada | N 51 23' | W 68 42' |  | 100 km | 214 
± 1  | Triassic-Jurassic |
| Popigai | Russia | N 71 39' | E 111 11' |  | 100 km  | 35.7 
± 0.2 | Eocene-Oligocene |
| Chicxulub | Yucatan, Mexico | N 21 20' | W 89 30' |  | 170 km | 64.98 
± 0.05 | Cretaceous-Tertiary |
| Sudbury | Ontario, Canada | N 46 36' | W 81 11' |  | 250 km | 1850 
± 3 | pre-Phanerozic |
| Vredefort | South Africa | S 27 0' | E 27 30' |  | 300 km | 2023 
± 4 | pre-Phanerozic |

## Yucatan Penninsula North(NASA Radar Topography Mission)

## The largest impact craters

**The largest impact craters**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## Manicouagan Crater (Canada)

**Manicouagan Crater (Canada)**

**diameter 45 miles**

## The largest impact craters

**The largest impact craters**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## PopagaiLandsat image

**Popagai**
**diameter 100 km**** **

**Landsat Image**** **

## The largest impact craters

**The largest impact craters**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## Chesapeake Bay

- Chesapeake Bay -- 90 km diameter

## The largest impact craters

**The largest impact craters**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## Deccan India Lava Flows

**Deccan India Lava Flows**

## Deccan Flood Basalts

- The greatest eruption on Earth in the last 100 million years

- 1.8 million square kilometers

## Large Igneous Provinces(Volcanic eruptions)

**Large Igneous Provinces****(Volcanic eruptions)**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## so --Are all extinctions attributed to impacts?Is the Nemesis theory now accepted?And what about those volcanic eruptions?

## Nemesis for Nemesis?Nature 311, Oct 18, 1984

**Mark Bailey** (page 602) “*Nemesis for Nemesis”*
*	**periodicity not perfect **[as in original Nemesis paper: Nature *308* 715-717, 1984**]*
*	**lifetime only 1 Gyr (ref to Clube and Napier) **[aioNp]*
*	****Hut paper amounts to a “a near retraction”**** **(words not those of Bailey!)*
*	**	**	**	**	**[so don’t bother reading it?]*
**Jack G. Hills** (page 636)
- 	*supports Nemesis hypothesis -- remaining lifetime ≈ 1 Gyr **[aioNp]*
*	**Nemesis may have perturbed orbit of Pluto*
**Piet Hut **(page 638)
- 	*lifetime of orbit is not constant, but decreasing linearly **[aioNp]**  *
*	**Simulations show 1 Gyr left.  Began with 5 Gyr **[aioNp]*
*	**plane of orbit ≈ that of Milky Way*
**Torbett and Smoluchowski** (page 641)
- 	*Giant molecular clouds disrupt orbit*
*	**	**but they mistakenly assumed such clouds were compact*
*	**	**error pointed out by *Muller and Morris*, Icarus* v. 65, p. 1-12.

*“**The trouble with most folks isn't so much their ignorance...*
*It's know'n so many things that ain't so.”            -- J. Billings*

## How can we get a betterhistory of impacts?

**Answer:**
**The Moon!**

**But -- only 3 craters have known ages**

**And -- trips to the moon are expensive!**

## lunar spherule

- diameter 100 microns (4 human hairs)

- Glass droplets (spherules) created by impact

**Apollo 14 site**

**Alan Shepard****2 mi from****Cone Crater**

## 138 Apollo 14 glass droplet ages

- Culler, Becker, Muller, Renne, Science **287**, 1785-1788 (2000)

- present

- moon creation

## postulatedNemesis orbitchangein the “recent” past(400 Ma)

## Walter Alvarez has dinner with Gene Shoemaker

**According to Walter, they discussed Rich’s star, **
**Nemesis.  Then, after dinner, Walter got his **
**fortune cookie.**

## Better than fortune cookie: Pan-Starrs(Panoramic Survey Telescope and Rapid Response System)

**U. Hawaii, MIT Lincoln Labs, Maui High Perf. Comp Center, SAIC**

## Large Synoptic Telescope

**By 2010, we will either find Nemesis, or prove it doesn’t exist.**

## What about the Permian-Triassic?

## Luann Becker: Buckyballs at the Permian Triassic

- with extraterrestrial argon!

- but: Ken Farley contradicts

## Nagging Puzzlesat the Permian-Triassic(250 Million years ago)

** ****why no iridium layer?**
**	****	****	**
** ****why huge vulcanism (Siberia)?**

- solution: vertical impact

## Normal vs. Oblique Impacts

- E. Pieraxzo and H. J. Melosh

- caveat: simulations done
- at low velocities

## Nagging Puzzles

- possible solution:
- 	triggered by impact

**Nagging Puzzles**

**at the Permian-Triassic****(250 Million years ago)**

** ****why no iridium layer?**
**	****	****	**
** ****why huge vulcanism (Siberia)?**

## Deccan Traps

**recall the vulcanism at the dinosaur extinctions**

## Antipodes?

*****

*****

**Deccan**

**Chicxulub**

## platetectonics movie

## Walter Alvarez: Deccan and Chicxulub NOT antipodes

**Walter Alvarez: ****Deccan and Chicxulub NOT antipodes**

- Nevertheless, someone proposes the idea of antipodes every year

## Large Igneous Provinces(flood basalts)

*When the Earth bleeds, it bleeds basalt.*

## 1984-2002How could an impact trigger a flood basalt?

**2002 -- a possible answer:**

## The Core

## Hot interior of Earth

- from Life Magazine
- 1955

## Earth interior(Shissell)

- from Shissell

## Burkavici Simulation

- simulation by
- Burkavici

- Mantle
- convection

## Plume simulationmovie

- simulation by
- Paul Tackley, UCLA

- Convective Instability
- Thunderstorm
- or
- Atomic Bomb
- or
- Heated oil (sautéing)
- or
- Lava lamp
- or
- Mantle Plume

## core mantle boundary

- E. Garnero, R. Jeanloz

- (liquid iron)

- “solid” rock
- (flows like
- silly putty)

## Jonathanupside down

## impact triggers avalanche

**impact triggers ****avalanche**

- Mutter LDEO
- graphics

**Tangential impact**
**of asteroid**

**spins the **
**mantle**

**but not**
**the core!**

**Core-mantle **
**slippage shear **
**triggers avalanche**

**, mantle plume, and vulcanism**

## The volcanic eruption is unlikely to be at the impact site.

**The volcanic eruption is unlikely to be at the impact site.**

## John Mutterimage

- diagram by John Mutter, LDEO

- Seismic profile imaging:
- red: the “rising African superplume”
- blue: the “descending slab”

## Downward plumes --into the liquid coreare even easierto trigger!

- avalanche cools the top
- 			of the liquid iron
- sinking iron disrupts
- 			the circulation
- dipole magnetism collapses
- magnetic field rebuilds
- 	(geomagnetic reversal or excursion)

## Earth Dynamo

## history of the reversals of the Earth’s magnetism

## 20 Jan 2002 draft of paper

**GEOMAGNETIC QUIET PERIODS.**  These are long periods when there are no geomagnetic reversals.  The most recent such period spanned the time from about 120 Ma to 85 Ma.  Could we find an explanation for such a quiet period, within the context of our model?   The most obvious explanation is that such a quiet period is the consequence of a very large avalanche, perhaps spontaneous or perhaps triggered by a large impact.  Such a large avalanche might destroy all sedimentary mounds, and give a general smoothing to the core-mantle boundary.  It would then take a long time for the mounds to rebuild to their angle of repose.  The gradual recovery of the rate of reversals (effectively a linear rise from 85 Ma to the present is observed) is consistent with this picture.  However, we also expect to be able to observe a consequence of the event which started the quiet period.  We might expect there to be a large plume (basaltic flow) near the beginning of the period, or at least evidence of a large cometary impact.   As far as we know, this prediction is not verified.  There is no evidence of strong flow at 120 Ma.

## history of the reversals of the Earth’s magnetism

## GRL paper

## Summary

## Extinctions (and other things)for the last 250 million years

**Extinctions (and other things)****for the last 250 million years**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## impact triggers avalanche

**impact triggers ****avalanche**

- Mutter LDEO
- graphics

**Tangential impact**
**of asteroid**

**spins the **
**mantle**

**but not**
**the core!**

**Core-mantle **
**slippage shear **
**triggers avalanche**

**, mantle plume, and vulcanism**

## Nemesis(Time)

**Alan Shepard****2 mi from****Cone Crater**

## Pan-Starrs(Panoramic Survey Telescope and Rapid Response System)U. Hawaii, MIT Lincoln Labs, Maui High Perf. Comp Center, SAIC  

**By 2010 we’ll know if Nemesis is there, or not there.**

## The paradox of science:

- The more you learn, the more you don’t know.

## My favorite unanswered questions(and unproven hypotheses):

**What happened 250 Myr ago?**
**Does Nemesis exist?**
**Role of volanic eruptions?**
**Deep underground avalanches?**
**Link to geomagnetic reversals?**

## Scientific research and  Sisyphus

**Albert Camus: Sisyphus is happy.**

- The  king of Corinth condemned forever to roll a hugh stone up a hill in Hades only to have it roll down again on nearing the top.

## There is a lot more that we don’t knownow, than we didn’t know 25 years ago.

***There is a lot more that we don’t know******now, than we didn’t know 25 years ago.***

***And in science, ***
***	******	******that is wonderful progress!***

## Richard A. Mullerhttp://muller.lbl.gov

**Richard A. Muller****http://muller.lbl.gov**

**Quark Matter 2004**

***There is a lot more that we don’t know******now, than we didn’t know 25 years ago.***

## The End

## Hintergrund plume

## Extinctions (and other things)for the last 250 million years

- Chicxulub

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

- Iridium 4

- Iridium 0.3

- Iridium 15

## Slide 135

## Interior of Earth

- from Wiley

## Extinctions (and other things)for the last 250 million years

- Chesapeake Bay &
- Popagai       Iridium 4

- Chixulub
- Iridium 15

- Manicouagan
- Iridium 0.3

- Iridium 5

- Siberian

- Columbia?

- Ontong-Java

- Central
- Atlantic

**Key**
- Extinctions (black)
- Large craters (blue)
- Iridium ppb (green)
- Flood basalts (red)

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Wignall, Haggerty

- Deccan

- Caribbean/
- Colombian

## Flood basalts & mass extinctions

- M. Rampino, V. Cortillot, B. Haggerty, others
- thanks to W. Alvarez and D. Shimabukuro

- Basalt flows > 200,000 km3

- Extinctions placed at boundaries

## Iridium 35 Myr agoEocene-Oligocene

**Iridium 35 Myr ago****Eocene-Oligocene**

**Iridium 35 Myr ago****Eocene-Oligocene**

## Extinctionsfor the last 250 million years

- from D. Raup and J. Sepkoski, 1984

## iridium

## The largest impact craters

**The largest impact craters**

- Extinctions: Sepkoski, Muller     Craters: Koeberl         Iridium: Asaro, Orth, others	Volcanism: Ernst & Buchan

## Barringer meteor crater in Arizona

**Barringer meteor crater in Arizona**

## Deccan Traps II

## Permian-Triassicmap

- courtesy of Christopher Scotese

## Columbia River Flood Basalts

- associated with the extinctions 15 million years ago?