Walter Alvarez
Walter Alvarez is a professor in the Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

 and Planetary Science
Planetary science
Planetary science is the scientific study of planets , moons, and planetary systems, in particular those of the Solar System and the processes that form them. It studies objects ranging in size from micrometeoroids to gas giants, aiming to determine their composition, dynamics, formation,...

 department at the University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

. He is most widely known for the theory that dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s were killed by an asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

 impact, developed in collaboration with his father, Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...

 winning physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

 Luis Alvarez
Luis Alvarez
Luis W. Alvarez was an American experimental physicist and inventor, who spent nearly all of his long professional career on the faculty of the University of California, Berkeley...



Born in Berkeley, California
Berkeley, California
Berkeley is a city on the east shore of the San Francisco Bay in Northern California, United States. Its neighbors to the south are the cities of Oakland and Emeryville. To the north is the city of Albany and the unincorporated community of Kensington...

, he earned his B.A.
Bachelor of Arts
A Bachelor of Arts , from the Latin artium baccalaureus, is a bachelor's degree awarded for an undergraduate course or program in either the liberal arts, the sciences, or both...

 in geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...

 in 1962 from Carleton College
Carleton College
Carleton College is an independent non-sectarian, coeducational, liberal arts college in Northfield, Minnesota, USA. The college enrolls 1,958 undergraduate students, and employs 198 full-time faculty members. In 2012 U.S...

 in Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...

 and Ph.D.
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...

 in geology from Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....

 in 1967.

His grandfather is the famed physician Walter C. Alvarez
Walter C. Alvarez
Walter Clement Alvarez was an American doctor of Spanish descent. He authored several dozen books on medicine, and wrote Introductions and Forewords for many others....

 and his great-grandfather, Spanish-born Luis F. Alvarez
Luis F. Alvarez
Luis Fernández Álvarez was a Spanish American physician and researcher who practiced in both California and Hawaii.Fernández was actually his principal surname...

, who worked as a doctor in Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, developed a method for the better diagnosis of macular leprosy
Leprosy or Hansen's disease is a chronic disease caused by the bacteria Mycobacterium leprae and Mycobacterium lepromatosis. Named after physician Gerhard Armauer Hansen, leprosy is primarily a granulomatous disease of the peripheral nerves and mucosa of the upper respiratory tract; skin lesions...

. His great-aunt Mabel Alvarez
Mabel Alvarez
Mabel Alvarez was an American painter. Her works, often introspective and spiritual in nature, and her style is considered a contributing factor to the Southern California Modernism and California Impressionism movement..-Life:She was born to a prominent Spanish family who lived on the island of...

 was a noted California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 artist and oil painter.

He worked for American Overseas Petroleum Limited in the Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

, and in Libya
Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....

 at the time of Colonel Gadaffi
Muammar al-Gaddafi
Muammar Muhammad Abu Minyar Gaddafi or "September 1942" 20 October 2011), commonly known as Muammar Gaddafi or Colonel Gaddafi, was the official ruler of the Libyan Arab Republic from 1969 to 1977 and then the "Brother Leader" of the Libyan Arab Jamahiriya from 1977 to 2011.He seized power in a...

’s revolution. Having developed a side interest in archaeological geology, he left the oil company and spent some time in Italy
Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

, studying the Roman volcanics
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

 and their influence on patterns of settlement in early Roman
Ancient Rome
Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....


Alvarez then moved to Lamont-Doherty Geological Observatory
Lamont-Doherty Earth Observatory
The Lamont–Doherty Earth Observatory is a research unit of Columbia University located on a campus in Palisades, N.Y., north of Manhattan on the Hudson River.- History :...

 of Columbia University
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...

, and began studying the Mediterranean tectonics in the light of the new theory of plate tectonics
Plate tectonics
Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...

. His work on tectonic paleomagnetism
Paleomagnetism is the study of the record of the Earth's magnetic field in rocks. Certain minerals in rocks lock-in a record of the direction and intensity of the magnetic field when they form. This record provides information on the past behavior of Earth's magnetic field and the past location of...

 in Italy led to a study of the geomagnetic reversal
Geomagnetic reversal
A geomagnetic reversal is a change in the Earth's magnetic field such that the positions of magnetic north and magnetic south are interchanged. The Earth's field has alternated between periods of normal polarity, in which the direction of the field was the same as the present direction, and reverse...

s recorded in Italian deep-sea limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

s, and he and his colleagues were able to date the reversals for an interval of more than 100 million years of Earth history.

Impact theory

Alvarez and his father Luis W. Alvarez are most widely known for their discovery (with Frank Asaro
Frank Asaro
Frank Asaro is an Emeritus Senior Scientist at the Lawrence Berkeley National Laboratory associated with the University of California at Berkeley...

 and Helen Michel) that a clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

 layer occurring right at the Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

The Tertiary is a deprecated term for a geologic period 65 million to 2.6 million years ago. The Tertiary covered the time span between the superseded Secondary period and the Quaternary...

 (K-T) boundary was highly enriched in the element iridium
Iridium is the chemical element with atomic number 77, and is represented by the symbol Ir. A very hard, brittle, silvery-white transition metal of the platinum family, iridium is the second-densest element and is the most corrosion-resistant metal, even at temperatures as high as 2000 °C...

. Since iridium enrichment is common in asteroid
Asteroids are a class of small Solar System bodies in orbit around the Sun. They have also been called planetoids, especially the larger ones...

s, but very uncommon on the Earth, they further postulated that the layer had been created by the impact
Impact event
An impact event is the collision of a large meteorite, asteroid, comet, or other celestial object with the Earth or another planet. Throughout recorded history, hundreds of minor impact events have been reported, with some occurrences causing deaths, injuries, property damage or other significant...

 of a large asteroid with the Earth and that this impact event was the likely cause of the Cretaceous-Tertiary extinction event
Cretaceous-Tertiary extinction event
The Cretaceous–Paleogene extinction event, formerly named and still commonly referred to as the Cretaceous-Tertiary extinction event, occurred approximately 65.5 million years ago at the end of the Maastrichtian age of the Cretaceous period. It was a large-scale mass extinction of animal and plant...


This iridium enrichment has now been observed in many other sites around the world. And further, the very large Chicxulub crater
Chicxulub Crater
The Chicxulub crater is an ancient impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is located near the town of Chicxulub, after which the crater is named...

 was identified and is now regarded as the definitive evidence of a large impact. Consequently, a majority of scientists now accept the impact scenario as the most likely cause for the K-T extinction event which occurred 65 million years ago and eliminated 75% of all species, including all non-avian dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s. His book, T. Rex and the Crater of Doom, details the discovery of the K-T extinction event.

In addition to his interest in extinction events and impacts, Alvarez has contributed to the understanding of Mediterranean tectonics, Roman
Ancient Rome
Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

 geology and archeology, and the establishment of magnetostratigraphic correlations.

Big History

Alvarez began teaching a course in Big History
Big History
Big History is a field of historical study that examines history on large scales across long time frames through a multidisciplinary approach, focusing on both the history of the non-human world and on major adaptations and alterations in the human experience...

 at UC Berkeley in 2006 under the title "Big History: Cosmos, Earth, Life, Humanity." According to Alvarez, Big History is the "attempt to understand, in a unified and interdisciplinary way, the history of the Cosmos, Earth, Life and Humanity." This definition was later adopted by the International Big History Association (IBHA). Alvarez's course is open to all majors and grade levels and seeks to provide a broad understanding of the past, present and future.

Alvarez is also one of the founding members of the IBHA, presently serving on the advisory board.

Alvarez's most recent contribution to the field has been the creation of a zoomable, interactive timeline for the field of Big History in partnership with Microsoft Research
Microsoft Research
Microsoft Research is the research division of Microsoft created in 1991 for developing various computer science ideas and integrating them into Microsoft products. It currently employs Turing Award winners C.A.R. Hoare, Butler Lampson, and Charles P...

 called ChronoZoom. ChronoZoom is a computer-graphical approach to dealing with this problem of visualizing and understanding time scales, and presenting vast quantities of historical information in a useful way. ChronoZoom was introduced at the 97th Annual Faculty Research Lecture at UC Berkeley. Video recording of the talk.

Awards and honors

Alvarez is the recipient of numerous awards and honors. He was elected a Fellow of the American Academy of Arts and Sciences
American Academy of Arts and Sciences
The American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...

 in 1983, and elected a member of the National Academy of Sciences
United States National Academy of Sciences
The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...

 in 1991. He was awarded the 2006 Nevada Medal, the 2008 Vetlesen Prize
Vetlesen Prize
The Vetlesen Prize is awarded from Columbia University's Lamont-Doherty Earth Observatory and the G. Unger Vetlesen Foundation.-Background:The Vetlesen Prize has been described as an attempt to establish an equivalent of a Nobel award for geophysics or geology...

, and the Penrose Medal
Penrose Medal
The Penrose Medal was created in 1927 by R.A.F. Penrose, Jr. as the top prize awarded by the Geological Society of America to those who advance the study of geoscience.-Award winners:* 2011 Paul F. Hoffman* 2010 Eric J. Essene* 2009 B. Clark Burchfiel...

 from the Geological Society of America
Geological Society of America
The Geological Society of America is a nonprofit organization dedicated to the advancement of the geosciences. The society was founded in New York in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitchcock, John R. Proctor and Edward Orton and has been headquartered at 3300 Penrose...

. In 2005, he received the doctorate "Honoris Causa"
Honorary degree
An honorary degree or a degree honoris causa is an academic degree for which a university has waived the usual requirements, such as matriculation, residence, study, and the passing of examinations...

 in Geological Sciences from the University of Siena
University of Siena
The University of Siena in Siena, Tuscany is one of the oldest and first publicly funded universities in Italy. Originally called Studium Senese, the University of Siena was founded in 1240. The University has around 20,000 students, nearly half of Siena's total population of around 54,000...

, Italy.

Further reading

  • T. Rex and the Crater of Doom by Walter Alvarez ISBN 0-375-70210-5
  • The Mountains of Saint Francis: The Geologic Events that Shaped Our Earth by Walter Alvarez (W. W. Norton, December 2008)

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.