Sunday, March 23, 2008

(Petroleum) geology in the movies: There Will Be Blood


[This is a contribution to Accretionary Wedge #7.]

One of the most memorable movies I have ever seen happens to be about a geologist who strikes it rich with oil in Southern California of the early 1900s. It is also probably the only movie with quite a bit of geology in that has won two Oscars (but I am not really a movie junkie so corrections are welcome).

Of course, I am talking about There Will Be Blood, director Paul Thomas Anderson's epic story about greed, religion, vengeance, murder, and other delightful human endeavors, written, shot, and acted so well that it is an instant classic, a piece of work comparable to the greatest Greek tragedies. Daniel Day-Lewis took home a second Oscar for his work, and there is a good reason for that: his performance is so powerful that in my mind the only other film character of comparable strength and weight and effect is John Proctor in "The Crucible", ...which also happens to be played by Daniel Day-Lewis.


Despite (and because of) its greatness, this movie is not for the faint-hearted. It is very unlike the average Hollywood production, and, if you want to leave the theater with that sweet reassurance of knowing exactly what is good and what is bad, well, then skip this one. Despite the almost unequivocal depiction by critics of the Daniel Day-Lewis character as a monster - and, I admit, Daniel Plainview is not exactly a charming person -, let's recognize that many of his thoughts and emotions are not foreign to most individuals that belong to the 'Homo sapiens' species. To me, the most scary and most monstrous character of the movie is Eli Sunday, the equally greedy but extremely irrational and hypocritical church leader and faith healer, played very convincingly by Paul Dano.

In any case, it is worth suffering through the two-and-a-half hours, if for nothing else but the realistic depiction of the oil industry at the beginning of the twentieth century. The movie does very well in terms of 'geological correctness'; certainly much better than most disaster movies with Bruce Willis in the driving seat saving the World from the evil forces of Nature. The only minor issue I can think of is whether it is possible to find oil in a silver mine (Daniel Plainview is a silver prospector before he turns into an oil man). It's been a long time since I read anything about ore deposits, but silver likes to accumulate in somewhat hotter different places than oil (unless it is in placer deposits).


Still, the best geological 'delicacy' in the movie comes at the very end. I would have never thought that you can make petroleum geology (or reservoir engineering) the centerpiece of a shocking movie scene, replete with human tragedy and profound proclamations about delicate philosophical issues.

Further reading: an excellent little piece about the geological aspects of the movie here.

And finally, here is a passage that gives an idea of how some people think about geologists (source):
"The fact is, Plainview is barely human to begin with, so watching him grow coarser and uglier and more full of himself seems a theme more suited to a geologist than a storyteller."
Ouch.

Sunday, March 09, 2008

Some questions about the 'megatsunami-chevrons'


The allegedly tsunami-related chevron-shaped nearshore deposits are back in the center of attention, at least among geo-bloggers. And rightly so: the idea that lots of coastal sand sheets all over the world were generated by relatively recent, impact-related mega-tsunamis of unimaginable scale is a fascinating hypothesis and, if proven true, it would revolutionize not only our understanding of frequency of meteorite impacts, but also change the predominant views about coastal geomorphology.

However, I have to confess that I find the geomorphologic and sedimentologic side of the argument fairly weakly constructed and documented, at least in the papers I was able to google up. Here are a few questions that could be asked to clarify some issues.

Many of the aerial photographs of the so-called chevrons could be used as textbook examples of parabolic dunes. Parabolic dunes are U-shaped wind-blown dunes usually fed by coastal sand deposits. Their nose points in a downwind direction, that is, the opposite way from barchan dunes. While wind strengths, direction, and sediment source are the main players in the generation of barchan dunes, vegetation plays a key role in the development of parabolic dunes. The 'arms' of a parabolic dune are left behind because they have a lower migration rate than the main body and the nose. The lower migration rate is due to plant growth in areas of lower sedimentation and/or erosion. There is a strong correlation between vegetation cover and dune migration rate or activity. This image comes from a recent paper by Duran et al.,


and it shows active (on the left) and inactive (on the right) parabolic dunes. Here is a sketch (source):


So the question is: if 'chevrons' are indeed different from classic eolian parabolic dunes, what is this difference, both geomorphologically and sedimentologically? Are they internally stratified? Do they show large-scale cross-bedding? What are the typical grain size distributions? Are they different from typical wind-blown sand? (One of the arguments is that large boulder fields occur in several places; however, my impression is that the boulders described here do not occur within, below, above, or right next to any chevron deposits. This short report claims that large pieces of rock are all over the place in the Madagascar chevrons, but no actual data is presented). The Madagascar chevrons featured in the New York Times show the signatures of typical parabolic dunes: U-shape, vegetated back sides and sandy crest plus nose. Why would an old tsunami deposit be vegetated only in certain places? The simple fact that these dunes are not entirely covered by vegetation suggests that their sandy parts do consist of wind-blown sand. Of course, tsunami deposits can be reworked by the wind, but why would the tsunami-related morphology be so well in tune with the eolian signature?

Second, if the chevrons are indeed produced by tsunamis, the tsunamis must have been humongous. Dune heights are related to flow depth, and a rule of thumb is that flow depth has to be around 6 times the dune height. So a 50 m high dune would require a 300 m high wave. Is that really possible? How big an impact do you need to generate such humongous waves? Also, what about the backwash? Why are most of the chevron dunes pointing systematically in one direction, and do not seem to be altered by any seaward oriented flow?

Third, are any features of the chevrons consistent with what we know about well-documented recent and ancient tsunami deposits? Tsunami-related sandy layers tend to be comparable to turbidites: largely unstratified, normally graded units suggesting rapid deposition from flows of decreasing velocity; they do not show large-scale cross bedding that requires relatively steady flow over longer time scales. In contrast, the chevron morphologies suggest that they are internally well-stratified, as the result of stoss-side avalanches. Here is a sand layer from the 1998 Papua New Guinea tsunami (source):



Obviously, it may turn out that there are tsunami-related coastal dunes and wind-blown parabolic dunes, with very similar morphologies, but fundamentally different origins. At the moment, the geomorphologic and sedimentologic evidence for this extraordinary hypothesis seems quite preliminary. And, needless to say, extraordinary claims require extraordinary evidence.

ps. 1: Lots of information on tsunami deposits here.
And a paper arguing for wind-blown origin of some deposits from the Bahamas, previously interpreted as tsunami-related: Kindler, P. & Strasser, A. (2000) Palaeoclimatic significance of co-occurring wind- and water-induced sedimentary structures in the last-interglacial coastal deposits from Bermuda and the Bahamas. Sedimentary Geology 131, 1-7.

ps. 2: More good stuff on megatsunamis and their deposits at Highly Allochthonous.

Saturday, March 01, 2008

Teaching of evolution in Romania: an endangered species


Romania is one of those countries that, after the fall of supposedly atheistic communist governments, are still struggling with the place of religion in public life and in education. The new Romanian constitution goes beyond guaranteeing freedom of religion and explicitly endorses state support for religious organizations ("Religious cults shall be autonomous from the State and shall enjoy support from it, including the facilitation of religious assistance in the army, in hospitals, prisons, homes and orphanages." - article 29). Yes, that is right: religious cults are autonomous but they enjoy state support. In other words, they do what they want with taxpayer money. Historically established religious denominations get government recognition; this is a major issue, because in practice only those religions enjoy 'religious freedom' who are recognized by the government. In other words, "Recognized religions have the right to establish schools, teach religion in public schools, receive government funds to build churches, pay clergy salaries with state funds and subsidize clergy's housing expenses, broadcast religious programming on radio and television, apply for broadcasting licenses for denominational frequencies, and enjoy tax-exempt status." (source). Note that the majority of Romanians see absolutely no problems with the government giving money to religious organizations, including funding for teaching religion in public schools. Religious institutions enjoy almost unlimited trust from the public (as opposed to the senate, the parliament, or universities), and if you dare to criticize a priest or a religious organization, you will quickly find yourself under a flood of attacks from people of all walks of life.

In parallel with the state-supported resurgence of religious life, the boundaries between secular and religious education are getting blurred. At the end of 2006, the secretary of state for research and education at that time, Mihail Hardau, signed a ruling that eliminated virtually all references to evolution from the science standards for public schools. In the meantime, 73% of the Romanian high-school students already think that the universe and humans were created by God. Scientific literacy is so low in the country that very few people see this as a negative development; even some biology teachers say that Darwinism does not necessarily contradict creationism and it is out of date anyway. Most journalists and politicians who express an opinion on the subject only prove that they did not even take the time to look up the words "Darwinism" and "evolution" in a dictionary.

This is sad news for me. I learned basic biology in communist Romania, in the eighties, and at that time there was no place for God and creationism in biology classes.[Of course, that was about the only good thing about communism -- so I am delighted it is a thing of the past, do not get me wrong]. Although my understanding of evolution largely comes from popular science books rather than those old biology lectures, at least you could not finish high school without hearing about Darwin and evolution. Now it is different: it has become difficult to get through the public education system without being indoctrinated (on taxpayer money) with the dogma of your favorite religion, and you might only hear about Darwin in the context of outdated atheistic thinkers who are not relevant any more.

If you want to help, here is the email address of the Romanian Ministry of Education: informare.publica@medu.edu.ro; more info here. Also, if you have a blog or website, feel free to spread the word. More people in Romania and outside Romania need to realize that the integrity of science education in one of the largest countries in Europe is at stake here.
 
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