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Revisiting The Core
Annotated list of references for geologic mapping in Iraq (supplemental information for the October issue of Geotimes)
Two parts history, one part travel writing and one part popular science, Simon
Winchesters Krakatoa is an enjoyable and informative read. Like
his very popular book The Map That Changed the World, which discusses
William Smith and his now-famous 1815 map, Winchesters latest work reflects
his earth science roots; he majored in geology at Oxford. But this time, he
focuses on a non-human subject Krakatoa volcano on an island in Indonesia.
Krakatoas 1883 eruption is one of the largest on historical record, killing more than 34,000 people and reducing the island to one-third its original size. The eruption is also notable for captivating world attention and highlighting the growing interconnectedness of the global village. Krakatoas eruption was one of the first major disasters widely broadcast through undersea telegraph cables; its effects were observed worldwide through global cooling, spectacular sunsets and sounds of the explosion heard up to 2,700 miles away. The eruption also provided a deadly demonstration of the indirect hazards of volcanic eruptions, such as tsunamis, and the near sterilization of the island made it a key site for biologic studies of colonization.
Recent popular books on volcanoes, such as Volcano Cowboys by Dick Thompson or the competing books on the Galeras disaster by Victoria Bruce and Stanley Williams, concentrate on the human drama of volcanologists at work. Winchester has set about a more difficult task, focusing on the volcano itself; Im surprised at the books popularity, with strong reviews and high sales rankings on Web-based bookseller sites.
Winchester begins Krakatoa with a brief history of Indonesia, emphasizing the development of trade, Dutch administration of the former colony and Islam. He then spends considerable time developing a context for the eruption including descriptions of contemporary scientific knowledge, undersea telegraph cable systems and life in the region. The eruption itself occupies the middle-third of the book, and Winchester does his best to describe it from all possible perspectives ships at sea showered with pumice, shut-in Dutch expatriates watching earthquake ripples in their water barrels and villagers on the beach running for their lives from tsunamis. The final chapters discuss current geologic knowledge and biologic studies of the island, as well as the role of the eruption in the rise of militant Islam in Indonesia.
Krakatoa is not a perfect book. Written in chronologic order but organized by subject, some chapters feel redundant and disjointed. And though at times brilliant, the writing can be overly or inappropriately descriptive. Krakatoas eruptions, for example, are described as the volcano having lifted its skirts. As a consequence, complex geologic points can be difficult to follow. The book also goes to great lengths to describe the 1883 eruption from different perspectives, perhaps to illustrate the conflicting pictures portrayed by first-hand accounts. Some editing and correlations would have made these more accessible, as would a single map of key locations and events.
Geology comes up multiple times, including especially lengthy and variably relevant descriptions of plate tectonic theory and its development. In these sections, several factual errors stand out, particularly a glaring one regarding rock magnetism. The book also exaggerates certain concepts, such as the misconception that seismically caused cracks in the earth swallow people. Other problems include the omission of important information such as the optical and other atmospheric effects of volcanic sulfur, and a lack of contemporary information on subduction-zone volcanology. Winchester affords scant discussion to the modern Krakatoa work of Haraldur Sigurdsson and the book Krakatau, 1883: The Volcanic Eruption and Its Effects, by Tom Simkin and Richard Fiske. The insight of these and other scientists could have played a more prominent role in the text and figures, some of which are clearly derivative but lack primary citations. In fact, Winchester points out near the books end that his copy of Simkin and Fiskes work has been thumbed through to the point of destruction. Unimpressed, Simkin and Fiskes critical review of Winchesters book in the July 4 Science focuses almost wholly on the works scientific shortcomings.
Although these errors and omissions are significant and could have been easily corrected, they will not seriously mislead or detract from the experience of the lay reader. The most important scientific point, that volcanism at Krakatoa is caused by subduction of a tectonic plate, comes across clearly. Geologists and teachers will need to ignore some of the erroneous details, but they will find the vivid descriptions of eruptive events interesting and useful. The history and global context of the eruption will engage readers, returning them to 1883 to experience it all firsthand and understand why it still captivates the world. The relationship of the eruption to the rise of Islam is also well described and not overstated, as popular works often do.
Winchester suggests that, in order to foment rebellion, the mullahs held up the eruption as an example of Gods displeasure carefully discussing it within the context of local events and Dutch colonial excesses. Readers interested in these historical aspects might also enjoy Pamela Swadlings Plumes from Paradise: Trade Cycles in Outer Southeast Asia & Their Impact on New Guinea & Nearby Islands Until 1920 or David Keys Catastrophe, which contends that a sixth century eruption in the vicinity of Krakatoa redefined the world order.
On a final note, much of the books writing is a pleasure to read. Other works often describe natural phenomena with dry terminology; however, Winchesters colorful descriptions leave the reader with the impression that he thoroughly enjoyed writing this book. It will suffuse anyone with a sense of wonder about Earth and its volcanoes, as well as offering a clear example of how the steady march of science in this case, plate tectonic theory can help us understand our world. In this time when the creationism debate is rearing its ugly head again, I can only hope to see more books such as Krakatoa written and read.
In The Core,
Earths core has stopped spinning thanks to a secret government
screw-up. As a result, the planets magnetic field begins to weaken, causing
all sorts of problems. People die suddenly, birds become navigationally inept,
and compasses drift off course. In one of the best scenes of the movie, Major
Beck Childs (Hillary Swank) helps save the shuttle Endeavor from crashing into
downtown Los Angeles by using old-fashioned geometry, a map and a pencil to
plot a better landing course.
Childs then joins our hero, geophysicist Josh Keys (Aaron Eckhart), to help save the planet itself. The two are part of a team of terranauts who must drill their way to the interior of Earth and set off nuclear bombs in its outer core. This, they believe, will return the cores natural spin and reset the magnetic field. As they begin their journey, the weather takes a turn for the worse and the unusual. Beautiful auroras are seen every night in Washington, D.C., for example, and lightning storms ravage cities around the world. The threat of solar radiation burning the planet to cinders begins in San Francisco.
Joining me at the movies was Director emeritus Hatten Yoder from the Geophysical Laboratory of CIW, who admitted he hadnt seen a movie in a theater in more than 15 years. From CIWs Department of Terrestrial Magnetism was post-doc Steven Hauck and staff members David James and Alan Linde, whose wife Caroline also joined us.
As we bought a bucket of popcorn to share, James explained his criteria for a quality science fiction film. The primary requirement for a good science fiction movie is one leap of faith, he said. Once you accept that, everything else bridges scientifically, logically and consistently. Otherwise the movie doesnt seem believable.
That didnt bode well for The Core, but James was willing to give it a go.
The lights in the theater dimmed and Yoder turned to whisper, I hope these people brought their asbestos suits. It gets hot down here, in the core. Indeed, 3,500 degrees Celsius, he added.
The Core begins in London with a series of unexplained deaths and a dramatic frenzy of pigeons in Trafalgar Square. Then the scene turns to geophysicist Josh Keys at the University of Chicago. Sound waves lose frequency as they travel through denser material, he says to a classroom of students. What was that, Keys? I think he was referring to attenuation, Linde explained after the movie. But you cant change frequency, just amplitude. Uh-oh, not even 10 minutes into the show and the leaps of faith are starting. No wonder Keys Geology 101 students are falling asleep or doing their nails.
Thankfully the FBI pulls Keys from his class to bring him and his French buddy Serge Levesque (Tcheky Karyo) who we learn later is not only a biochemist, but also an atomic weapons expert in to help them explain the mysterious deaths and cool Hitchcock-like pigeon behavior. As it turns out, only people with pace-makers died.
Back in the geology office, a graduate student explains the bird-storm phenomenon: Ions in birds brains align with the magnetic field on Earth. Remember that sentence. Im not certain, but I think it is the only time in the movie where Earths magnetic field is not mistakenly referred to as an electromagnetic field. This inaccuracy irritated the Carnegie geophysicists throughout the film.
The movie takes its time developing the characters before throwing them together to adventure into Earths outer core. When the mission begins, the movie provides its own perspective on what the Earths interior might look like and how these brilliant people with varying backgrounds might interact. ...
What are some leaps of faith that the movie demands?
|* A spinning core generates Earths magnetic field.
Thats only partially right. Convection currents in the liquid part of the outer core do the job. As long as Earth is spinning, its core is spinning too; some scientists think it even spins a little faster than Earth.
* An element called unobtainium cannot only withstand increasing temperatures and pressures, but also gets stronger in the process.
As the movie recognizes, this element is unobtainable.
* The temperature in Earths interior is 9,000 degrees.
Thats heating it at least a thousand degrees more than most scientists would agree for Fahrenheit. The Core's Web site is more accurate.
* Without the magnetic field, solar winds and radiation would torch everything on the surface of the planet.
They might increase mutation rates, but they wouldnt burn skin in seconds or melt steel.
* The mantle is partially molten.
Sorry, solid as a rock. Yes, it does move about as fast as fingernails grow.
* The magnetic field would shut down in a year.
Geologic records show it takes hundreds to thousands of years to reverse the magnetic field, and that it has switched many times without destroying the planets surface. Of course, if a secret government act destroyed the cores ability to produce a magnetic field, all bets are off.
Did the movie get anything correct?
The core is about the size of Mars, Hauck said.
The thicknesses of the crust, mantle and core were also on target, and as far as fruit goes, a peach is a pretty good analogy to Earth. All agreed, too, that the scene with the shuttle is the best one in the entire movie although I would have to watch it again to check that Major Childs got her latitude and longitude correct. In reality, the Los Angeles River is between 33 and 34 degrees north latitude and at 118 degrees west longitude. If anyone else goes to see this movie, please let us know what she scribbled down as the latitude and longitude for the landing. The Carnegie geophysicists and I arent interested in watching The Core twice.
The Cores Web site
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Map of Iraq: Directorate General of Geological Survey and Mineral Investigations
by Z. J. Saad, H.H. Dikran and A.J., Hishaim (Bagdad). 1986. 1:1,000,000 scale.
A general geologic map keyed to named stratigraphic units typically without lithologic descriptions; the base map consists of major drainages and roads, which were found to have some internal distortion.
Tectonic map of Iraq: Directorate General of Geological Survey and Mineral
Investigations by T. Buday and S.Z. Jassim (Bagdad).1984. 1:1,000,000 scale.
A general tectonic map showing fold belts and basins; the base map consists of major drainages and roads, which were found to have some internal distortion.
Geological map of Iraq and southwestern Iran by Robertson Research International. 1987. 1:1,000,000 scale.
Derived from the maps listed above, but reinterpreted with satellite imagery (LANDSAT); general lithologies are described.
Groundwater resources of Iraq, provisional regional maps: Development Board, Ministry of Development, Government of Iraq by Ralph M. Parson Company (Los Angeles). 1957. 1:1,680,000 scale.
A folio of neatly hand-drawn maps including physiographic, generalized geologic (with brief lithologic descriptions), topographic, isohyetal, piezometric, isosalinity and nitrate ion distribution maps; the base map consists of major drainages roads.
Exploratory soil map of Iraq: Division of Soils and Agricultural Chemistry, Directorate General of Agriculture research and Projects, Ministry of Agriculture by P. Buringh (Bagdad). 1957. 1:1,000,000 scale.
Soil units have brief physiographic descriptions; the base map consists of major drainages and roads.
Geology of Iraq: a bibliography from 1968 to 1988. Journal of Geological Society of Iraq, 1988. v.21(1).