Through The Sandglass

Science writing - but where's the geology?

This will start of as a sort of book review, but move on to what seems to me to be an interesting question, and one on which I will seek your ideas.

Six months or so ago, Richard Dawkins's compilation, The Oxford Book of Modern Science Writing came out and it immediately joined my pile of good intentions. I have carried its intellectually and physically weighty 400 pages with me to Central Asia and back, but over the holidays, with a fire, a comfortable sofa and a few glasses of wine, I finally read it - cover to cover. Now I have to admit that I'm a foul weather fan of Dawkins - when the glass is half empty, the chips are down, push comes to shove and intelligent design is taught in science classes, I'm with him all the way. But when the glass is half full, I often wish that he would calm down a little, and perhaps check the mirror rather less often. But this compendium, including the brief introduction to each extract, is wonderful. I found myself reunited with old favorites - Rachel Carson, Richard Feynman, George Gamow, Steve Gould - but often pieces that I didn't know or, more likely, had forgotten. But there were also discoveries - I found myself delighted by Peter Medawar, convinced (again) that I should read Primo Levi and Douglas Hofstadter, and fascinated by Loren Eiseley. I was reminded why I find Carl Sagan infinitely more entertaining to read than to listen to. I was also reminded guiltily why I, like, I suspect, many, have A Brief History of Time on our bookshelf but have never made it all the way through. And, given my theme, I was pleased that the beginning of the first extract reads "Standing on our microscopic fragment of a grain of sand, we attempt to discover the nature and purpose of the universe which surrounds our home in space and time. Our first impression is something akin to terror........because of the material insignificance of our home in space - a millionth part of a grain of sand out of all the sea-sand in the world." (James Jeans, The Mysterious Universe). One of the science books I have enjoyed most over the last few years was also there, Per Bak's How Nature Works, with his introduction to the wonders of sand piles.

In short, read this book - it's compelling and inspiring.

Dawkins has just completed his tenure as the first holder of the Arthur Simonyi Chair of the Public Understanding of Science at Oxford (now held by Marcus du Sautoy, mathematician and engrossing writer). The Oxford Book of Modern Science Writing dramatically illustrates what excellent communication of science is about - and why it should be inspiring. Here are a couple of extracts that illustrate this, and its vital importance in today's world. First, from Arthur Eddington, the British physicist who, in 1919, used an eclipse of the sun to measure its bending of light and thus proved Einstein to be right. In 1940, in The Expanding Universe, he wrote:

Science has its showrooms and its workshops. The public today, I think rightly, is not content to wander round the showrooms where the tested products are exhibited; The demand is to see what is going on in the workshops. You are welcome to enter; but do not judge what you see by the standards of the showroom.

I was really struck by this compelling image - in my view, the way science is presented today in the media is as the showroom, things we know, none of the excitement of the unknown, the uncertainty, the workroom.

And then, Carl Sagan, writing in 1996 in The Demon-Haunted World: Science as a Candle in the Dark:

We've arranged a global civilization in which most crucial elements - transportation, communication, and all other industries; agriculture, medicine, education, entertainment, protecting the environment; and even the key democratic institution of voting - profoundly depend on science and technology. We have also arranged things so almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces.

So, a highly recommended, provocative, book. But I do have a couple of complaints. First, Dawkins explains in his introduction that "This is a collection of good writing by professional scientists, not excursions into science by professional writers." OK, this is his book, not yours or mine, but if part of the rationale for the collection is making science - particularly its workshops - accessible, then this is only part of such a mission. Yes, the creativity and articulateness of scientists is admirably demonstrated, but the other side of the coin deserves attention too  - where are Philip Ball, James Gleick, John Gribbin, Simon Winchester? Surely the "excursions" (a condescending way of putting it, don't you think?) of professional writers into the workshops can be equally compelling and equally powerful in making science accessible and exciting?

But mention of Simon Winchester (some of whose books, particularly The Map that Changed the World, I find better than others) raises the key question: where's the geology? In Dawkins's collection all the key strands of science are covered, from the quantum scale to the universe, via information theory and the Turing test, but, apart from two lovely paleontological pieces by Richard Fortey, geology is entirely absent. There is discussion as to what are the greatest discoveries in science during the last century - evolution (as it came to be mapped out by the "neo-Darwinists"), relativity, the double helix? There is no mention whatsoever of plate tectonics, surely an example of revolutionary science?

Is this the fault of Dawkins or of us as geologists? Professional geologists are as capable of writing well as other scientists and, among them, are those who can write superbly - is it simply that they tend not to write in the same vein that Feynman and Sagan did? I have a book titled Bedrock: Writers on the Wonders of Geology, published a couple of years ago and edited by Lauret E. Savoy, Eldridge Moores and his wife, Judith E. Moores. It's a great collection, covering everything from Pliny the Elder onwards. But, other than extracts from Steve Gould, Hans Cloos, and, again, Loren Eiseley, the modern pieces are largely by non-scientist writers (John McPhee, Barry Lopez and many others) rather than by professional geologists.

So, here's a question (I have some ideas, but I'm interested in yours): who are the geologists of the last century who have written great stuff - books, articles, whatever - on the excitement and the discoveries of our discipline, on what it's like to be a geologist, on what geologists do, and what gets them excited? And what are these best bits of geological science writing?

Dollars, roses, and cookies

Whenever I'm in this part of France, south of Perpignan, I make sure to visit the bijou town of Ceret, nestled (the word seems appropriate and less hackneyed here) in the foothills of the Pyrenees. Famed for its association with renowned artists, and home to a terrific modern art museum, the historic center winds around the classically French square of the Place des Neuf Jets, where, indeed, a fountain with nine outlets cascades beneath a venerable plane tree. Small cafes line the square, but the object of my pilgrimage is in one corner: the Galerie Vargas is a superb mineral and fossil shop. Monsieur Vargas can best be described as a character - small and wiry, of a certain age with a pony-tail and a twinkle in his eyes. Over the years, I have got to know him quite well - certainly well enough to know that, if the shop is closed in normal business hours, I can find him in the Bar Picasso and, as long as he is not in the middle of a beer and a game of chess, induce him to open up. As two geologists, our discussions of his treasures are good for my French and his English, and always a pleasure. Those discussions and their aftermath (inevitable purchases) often go on for some time - he is regularly off to his secret locations around the world and the gallery is routinely refreshed with new wonders (his latest specialty is spectacular amber).

Before Christmas, my purchases were modest, all French, and connected, in one way or another, with sand. A couple of exquisitely preserved sand dollars, I think Miocene. So named to reflect their currency-like morphology and, today, their being washed up on sandy beaches, they are, of course, echinoderms, relatives of the sea urchins, creatures that inspired my early interest in paleontology, an enthusiasm that was soon beaten out of me as a student by the sheer weight of terminology and classification. I found early echinoderms particularly interesting simply because of the bizarre and seemingly toxic relationship between their mouth and their anus; but, of course, they evolved to sort this out and go on to be a great success. Modern sand dollars tend, when alive, to be a rather delicate purple color and remarkably adept at burrowing their way into the sand of the shallow marine seabed, feeding on the incredible diversity of minute organisms that make the spaces between the grains their world. The rhythms and diversity of echinoderm designs is compelling, as is their evolutionary success story. 

Monsieur Vargas also had, in a humble brown cardboard box on the floor, a glorious garden of desert roses, disinterred from near Beziers, not far to the north, and recording distinctly more arid times (I'm looking out at the freezing rain that this normally sunny corner of France has decided to deliver). Formed of gypsum or selenite, these delicate little crystalline flowers incorporated desert sand grains as they grew, resulting in a fabric that is, if you wish to bandy about obscure terminology over dinner, referred to as poikilotopic. And, if your erudition is well-received, or the topic is found peculiarly seductive, you might even describe them as poikilotopic mimetoliths, thereby introducing an almost endless discourse for your rapt audience.  The term mimetolith was introduced by R.V. Dietrich, the prolific geowriter and Professor Emeritus of Central Michigan University. The word applies to any topographic feature or geological specimen that, with a little imagination, looks like something else, and that's true of desert roses in all their varying forms. See  http://www.cst.cmich.edu/users/dietr1rv/mimetoliths/ for a comprehensive (but not complete) survey of examples of mimetoliths and Andrew Alden's column http://geology.about.com/od/geologyandculture/a/greatstonefaces.htm for an interesting survey of body part mimetoliths.

And, finally, following mimetolithic seasonal inspiration, and after she had baked sand cookies (sables being the French version of shortbread), my wife whipped up a batch of desert rose cookies, roses des sables, which are, I suppose, culinomimetoliths - or not, as the case may be. But they are delicious (easy recipe available free on request).

Seasonal Sand Grains

Sand, Earth Systems, and the Importance of Size

 Now, back to the subject of this blog, but still following the global theme. In the course of researching and writing the book, I learned a lot and came across a wide range of topics that were new to me, many of them thought-provoking. Here's one particularly provocative example.

Sand, strictly, is defined only by its size range, its composition being of secondary importance; the size of sand grains determines how they behave and that behavior is unique and sometimes downright bizarre. Size is important.

Although born in Scotland, Philip H. Kuenen was an internationally-renowned Dutch sedimentologist in the last century, a great geologist with a passion for sand. Thanks to Kuenen, our understanding of turbidity currents, submarine canyons, and their associated depositional systems was set firmly on its feet. I came, essentially by accident, across the publication* of a talk that he had given in 1959 when he was invited by the Geological Society of South Africa to give their annual lecture in memory of Alex du Toit, a South African geologist who gave early support to the ideas of continental drift. Kuenen chose for his title “Sand—its origin, transportation, abrasion and accumulation.” In the talk, he strode boldly across the landscapes of sand on all scales, from how long it takes a grain to become round to mass transport in the desert, his "back of the envelope" calculations illustrating the dramatic scales and frequencies of our planet's processes. He concluded his talk with  a statement that I find particularly thought-provoking:

The size of the sand grains determines the mode of transportation. If the particles were much bigger they could not be moved by the wind and there would be no coastal dunes or sand deserts…The denudation of mountain chains would be a more laborious process…The all-important part played by sand in protecting coasts from wave attack would be largely suppressed, because rivers would not carry the pebbly quartz to the coast. Not much quartz would reach positions where turbidity currents could carry them to the deep-sea floor, and the few that were carried by such flows would travel less far. In fact dry land would be smaller, higher, and more siliceous.

On the other hand, if quartz left the parent rocks in much smaller particles than actually happens, these would be carried more easily by rivers and marine currents and also suspended in the air. A higher percentage would be lost from the continents to the deep sea. The continents would be less siliceous and thinner…and in general the protective cover of sand shielding more vulnerable material from weathering would be absent. Marine planation of the continents would be more active, because protective sands would have been wasted into the deep-sea. It thus appears probable that if quartz grains in granites were significantly bigger than they actually are, the continents would be smaller and steeper than we now find them. If granite quartzes were much smaller, the land would also be smaller but lower than at present.

This seems to me very much an anticipation of the yet-to-be-coined "earth systems" approach. Putting aside biogenic sands, the majority of sand grains in the world owe their origins to igneous activity and lithospheric process, their size range determined by plate tectonics, uplift and cooling rates, geothermal gradients and so on. Yet, as Kuenen suggests, there is feedback at work here, lithospheric processes being themselves influenced by the games that sand plays across the Earth's surface, games whose rules are determined by the size range of the grains. The size of sand grains makes the Earth look the way it does. Interesting and thought-provoking?

*Kuenen, Ph. H. Sand: Its Origin, Transportation, Abrasion and Accumulation. Annexure to vol. 62. Johannesburg: Geological Society of South Africa, 1959.

The International Geoblogosphere - continued

First of all, thanks to all the respondents to my previous post and appeal. I was looking for a shortcut to figuring out the international dimensions of the Geoblogosphere, and, thanks to the highly valuable community component of blogging, I have been enjoyably shoved up the learning curve.

After following various trails over the last 24 hours (well, with some sleep in between), two things stand out in addition to the pleasure of finding individual blogs. First, the most comprehensive listing that I have found is maintained by Robert Huber and Jens Klump in Germany at http://geoblogs.stratigraphy.net/?action=list, who also run the stratigraphy.net website and blog (http://stratigraphynet.blogspot.com/). Second, Chris Rowan pointed me to the Geoblogosphere survey that Callan Bentley had conducted a few months ago (http://nvcc.edu/home/cbentley/geoblog/2008/09/rise-of-geoblogosphere.html). Callan's map of the international distribution of geobloggers is interesting and informative - is there a way (and I ask this as someone for whom the workings of the stuff behind the monitor remain largely mysterious and intimidating) of putting these two sets of data together? In Callan's survey, the top two reasons given as dislikes about the Geoblogosphere were not enough geologists blogging and that it's too dispersed - it needs a directory. It also strikes me that, while the virtual and geography-free nature of the community is great, nevertheless there is value to awareness of local as well as global communities.

In a sense, I believe that one value of local communities relates to the more serious part of my previous post: to "broadcast" and stimulate (see the top three reasons for blogging in Callan's survey - anyone who blogs is, I believe, demonstrating enthusiasm and activity). I would like to think that the Geoblogosphere could actively provoke discussion of the AGI document and the issues it raises. From my own local perspective, for example, I strongly believe that the Geological Society in London has a role in the public and policy-making perception of these issues. But the GeolSoc is a great and venerable institution that still suffers from a degree of conservatism and the difficulties of reaching consensus to stick its institutional head above the parapet (having written that, I'll find out if anyone else at the GeolSoc is reading this!). Perhaps a concerted campaign through the UK geoblogging community could influence this in the right direction, a geoblog lobby? The GeolSoc might even have a role as providing a listing and aggregation of UK and international geoblogs.

The ability to link geographic geoblogging communities as well as thematic ones would be useful - your thoughts?

Meanwhile, I loved the response that Callan reports to why bloggers blog - "Cogito Ergo Blogo"

The International Geoblogosphere

As a new participant in the gloriously titled Geoblogosphere, a couple of things have come to my attention recently that I'd like to highlight. One of them is entertaining, the other deadly serious, neither of them directly to do with sand, but both linked to the international community.

First, for entertainment, Geotripper posted a geologist's version of the "100 things you've done" meme ((http://geotripper.blogspot.com/2008/12/100-things-youve-done-meme-geologists.html), to which the geoblogosphere, including myself, has responded with enthusiasm - there's a lively series of comments on Highly Allochthonous (http://scienceblogs.com/highlyallochthonous/) and the level of activity seems to have diminished attendance of AGU meeting sessions in San Francisco. Several comments have noted a degree of Americocentrism to the list; this seems to me fair enough since the origins are in the US, and it wasn't a problem for me since I have spent so much of my life geologizing around the US. But it does raise the question: where's the international geoblogosphere? Perhaps I just haven't found it, but, from my European perspective all the good blogs come from the US. So this is an appeal to locate international geobloggers - you must be out there.

The more serious issue also relates to the international earth science community. Andrew Alden's blog pointed me to the document "Critical Needs for the Twenty First Century: The Role of the Geosciences" put out by the AGI on behalf of its member societies (http://www.agiweb.org/gap/geotrans08.pdf). "The geoscience community of more than 120,000 geoscientists represented by the 44 member societies of the AGI stands ready to help deal with the challenges of modern life in a delicately linked Earth system." The document highlights seven critical challenges facing society, all of which are global headline issues and to all of which the geosciences and geoscientists have a fundamental contribution to make. Again, of course the document has a US focus, but the issues are global and the AGI putting this out has set a great example for the geological community around the world. The document needs to be broadcast and adapted and adopted by geosocieties globally - we all need to stick our heads above the parapet.

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Tsunami forensics - sand helping save lives

I was enjoying the cultural splendours of St Petersburg when the devastating tsunami of December 2004 hit. Since the only source of information that CNN news could present to us was their weather-person, I became, as the token geologist in our tour group, responsible for passing on what I knew and correcting media inaccuracies. The anniversary of that appalling event is now approaching, and there are several reports currently in the geo-news of the ongoing forensic work on the earthquake and the tsunami. Workers at Caltech have established that the 2004 and subsequent events only released stress along particular segments of the subduction zone (for example, the build-up since the major earthquake of 1861), and that other areas remain stressed and liable to rupture in the not-too-distant future. "From what we saw," says geologist Jean-Philippe Avouac, director of the Tectonics Observatory and one of the paper's lead authors, "we can say with some confidence that we're probably not done with large earthquakes in Sumatra." (http://www.sciencedaily.com/releases/2008/12/081203131042.htm). And, just to emphasize the continuing surprises that our planet has for us (i.e. the things that make geology exciting), research at the University of Washington has shown that the 2004 Sumatra earthquake triggered low-level seismic events along the San Andreas fault: "We found that an earthquake that happened halfway around the world could trigger a seismic signal in the San Andreas fault. It is a low-stress event and a new kind of seismic phenomenon," said Abhijit Ghosh, a University of Washington doctoral student in Earth and space sciences. (http://www.eurekalert.org/pub_releases/2008-12/uow-gio121008.php and read more at Andrew Alden's great portal to all things geological at http://geology.about.com/b/2008/12/11/triggered-tremor-from-half-a-world-away.htm).

But this is a blog about sand - where is all this seismology stuff leading? In order to have any hope of avoiding the tragedy of the 2004 event in the likely future earthquakes, a combination of approaches is needed. Prediction with sufficient accuracy remains out of the question, but the development of the Indian Ocean Tsunami Warning System (IOTWS) is vital, and the design and effectiveness of this system depends on our understanding of the character and timing of past tsunamis - hence the forensics. On an island just off the coast of Aceh most people safely fled to higher ground in 2004 because the island's oral history includes information about a devastating tsunami in 1907.

When you look at the "before and after" images of the Aceh coast, and if you can think beyond the scale of the human tragedy, one obvious question is "where have the beaches gone?"  The upper image shows the answer - strewn for long distances inland. (Images credit Ikonos images copyright Centre for Remote Imaging, Sensing and Processing, National University of Singapore and Space Imaging, see http://www.nasa.gov/vision/earth/lookingatearth/indonesia_quake.html). These deposits give us vast amounts of information about tsunamis past and present. The photo below shows a cross-sectional view of 2004 tsunami deposits at the village of Lampuuk in Aceh. A 73-cm thickness of sand was deposited over soil (dark material in bottom center), in beds indicating multiple pulses of sand deposition. The lowermost bed, 45 cm of sand grading upward from coarse to fine, settled from suspension in a single wave and can be used to characterize the wave's height and velocity (http://soundwaves.usgs.gov/2005/03/, photo by Guy Gelfenbaum).

The layers of sand swept inland by historic tsunamis provide a crucial historic and geologic record. Although destructive tsunamis are rather rare events at a given coastal location, to estimate the existing tsunami hazard properly, long-term observations are required. Geologic records of pre-historical tsunamis can extend the historical and instrumental records to the recent past and fill in gaps in the historic and geographic records. An international team, supported by the US IOTWS program, and led by Kruawun Jankaew of Chulalongkorn University in Thailand, have been digging hundreds of pits at locations in Thailand and Sumatra to reveal this record, and have recently reported their results (http://www.sciencedaily.com/releases/2008/10/081029141037.htm). The photo shows Dr. Kruawun in one of these excavations. The pit reveals a regular sequence of sand layers interrupting the normal dark soils - the topmost layer is the sand deposited by the 2004 tsunami, the lower ones successively older events over the last few thousand years. Radiocarbon dating of bark fragments in soil below the second sand layer led the scientists to estimate that the most recent predecessor to the 2004 tsunami probably occurred between A.D. 1300 and 1450 and there is clear evidence of two earlier tsunamis during the last 2,500 to 2,800 years.

The knowledge gained from this work contributes to an effective warning system and tsunami education. In the words of Dr. Kruawun, "Many people in Southeast Asia, especially in Thailand, believe, or would like to believe, that it will never happen again. This will be a big step towards mitigating the losses from future tsunami events."

So, I guess that the message here is that sand can help save lives. I shall end this post with what I think is a poignant and provocative image. this time from the sands left by a tsunami that devastated the Japanese island of Okushiri in 1993. A clock, half-buried in the sand, provided one small piece of timing data for the event (http://www.ngdc.noaa.gov/nndc/struts/results?eq_1=27&t=101634&s=0&d=4&d=44).

Knuts ancient and modern

In Knutsford, Cheshire (the UK one), the first Saturday in May is "Royal May Day," the "royal" referring to King Knut (or popularly, Canute), the Viking King of England a thousand years ago. Tradition on Royal May Day recognizes sand as symbolic of large numbers and fecundity - it's scattered in patterns around the houses of brides and small sand castles are built outside (the picture is from a sign in Knutsford and shows "sanding the streets" from around 1920). Legend has it that Knut, on meeting a wedding party after fording a river, emptied his shoe of sand and wished the couple as many children as there were grains - a prospect that might have caused the bride some alarm. Now of course this was the King Knut (or Canute) now famous for the legend of his sitting on the beach and failing to stop the waves and tides, but the story has become reversed from the original. Far from being a vain attempt to demonstrate his powers, Knut was intentionally demonstrating his lack of them. Either through piety, or to put the flattery of sycophants and flunkies to rest, or possibly both, he was conducting a graphic experiment to show that his powers were mortal.

Recent headlines in the British press, and his local community, have dubbed Peter Boggis the "modern King Canute." Boggis has the misfortune to live in the target zone of the most rapidly eroding piece of coastline in Britain. The low cliffs north of Southwold in Suffolk face the wrath of the North Sea (although "wrath" is a little unfair - the North Sea simply does what it always has done with no hidden agenda), and the result is that the cliffs are retreating at a rate of several meters every year - on average. Technically, Peter Boggis lives in the hamlet of Easton Bavents, but in reality the once-thriving market town, the most easterly parish in England, no longer exists - its remains are a couple of miles to the east under the North Sea and have been there since the seventeenth-century cliffs collapsed. A recent storm in 2001 put Boggis's house ten meters closer to the cliffs than it had been the previous day, and this dramatic erosional event spurred him and other local residents into action. Over a period of time, the 77-year-old retired engineer organized the delivery of 250,000 tons of soil and arranged its emplacement along the beach to protect the cliffs. The North Sea clearly regarded this as an affront and most of the material has now been moved on - but it was also deemed illegal activity - "unauthorised tipping" in the words of English law.

The problem was that the cliffs and their contents had been designated as an SSSI, a protected site of special scientific interest (for the details, see  http://www.english-nature.org.uk/special/sssi/sssi_details.cfm?sssi_id=2000508). The interest is in the sands in the cliffs, which record in detail the story of that part of England during the glacial and interglacial periods of the Pleistocene era. Not only do the sands document how the climate changed, but they contain key marine fossils and the remains of mammals that roamed Suffolk as sea-level dropped - mammoths, mastodons, giant deer, hippopotami, beavers, and so on. It's a unique record which, thanks to the activity of the North Sea, is being further revealed every day (the SSSI has had to be redefined, since it is no longer where it was).

A legal battle ensued between the latter-day Knut (also known as the "clifftop crusader") and English Nature, the Government's conservation agency which had designated the SSSI, and it has just been announced that Mr. Boggis has won his two-year battle in the high court of the UK (see, for example The Times, "The Clifftop Crusader wins his fight to repel the sea - by a technical knockout" - http://www.timesonline.co.uk/tol/news/environment/article5295682.ece). Mr. Boggis's understandable determination to battle both nature and English Nature highlights some important questions - which I shall raise, but not presume to answer. Putting aside for the moment the science dimension (although it's worth pointing out that the Easton Bavents cliffs are a source of real data for understanding today's climate changes), how much effort, time, and money should we put into the inevitably forlorn attempts at "preventing" natural coastal processes? The eastern coastline of the UK is littered with the battered remains of such attempts and huge amounts of money and sand are poured into "beach nourishment" projects all over the world - all of them temporary. Any stretch of coast anywhere on the planet has, at any given time, a sediment budget - sand and mud are carried from somewhere to somewhere else; disrupt that budget, either positively or negatively, and the whole thing is destabilized. Mr. Boggis himself used this principle in his defence: "Unusual winds and groyne problems for cliff man" ran one headline. While this may sound like a distressing conspiracy of medical problems, I should hasten to point out (to American readers) that a "groyne" in our bizarre English parlance is a structure (rock, wood, metal) built out from the beach to "protect" the shoreline. The photo at left is an example of a (typically ravaged) groyne on a different part of the coast. But groynes, inevitably, disrupt the sediment budget - they trap sand and prevent it being supplied to where it would normally be. Mr. Boggis cited the extension of groyne construction in the bijou artist colony village of Southwold as causing sand starvation, and hence aggravated erosion, along the shore beneath his house. He has a point - but it doesn't necessarily mean that his 250,000 ton disruption to the sediment budget is the answer. I pointed out in my November 23 post the invasion of Pensacola Beach by too much sand - the other side of the budget. The fact is that coasts are among the most dynamic environments on the surface of the Earth - when do we come to terms with the fact that attempting to fight or subdue or prevent that dynamism is an extraordinary waste of time, money, and other resources that, more often than not, could be better devoted elsewhere?

Images and wonder

Sometimes I just get sidetracked and other times I get overwhelmed - and now I'm both. I was working on the next post when the December issue of the National Geographic arrived, with the riveting piece by John Updike on "Visions of Mars". The article begins "Mars has long exerted a pull on the human imagination." It most certainly has, and the writing and the images in the article underscore this.(see http://ngm.nationalgeographic.com/2008/12/planet-mars/updike-text). This set me off on a diversionary quest to the sources of some of these extraordinary images, the art of a planet and the natural art of sand. NASA's site has, of course, a vast collection of imagery from the surface and from orbit, but then I discovered that the Lunar and Planetary Laboratory at the University of Arizona, a partner of NASA, has put up a collection of high-resolution Mars images - visit http://hirise.lpl.arizona.edu/  and chances are you'll get lost, as I did for a long time, in wonder and fascination. It's not that I haven't been lost in wonder before at data from so far away from home (I'm of a certain age - I still find the "small step for mankind" moment a mind-boggling event); but the wonder just doesn't go away (see earlier post on Phoenix and its collection of sand grains). So, simply feast your eyes and imagination on some samples and yes, feel free to just become lost for a while. And, if you visit the National Geographic site, you will also see a collection of wallpaper images - Patterns in Nature: Sand - our planet is pretty extraordinary, too.

[images credit: NASA/JPL/University of Arizona and NASA/JPL-Caltech/Univ. of Arizona]