I really enjoyed Freakonomics, and so it was disappointing to hear that the recently-released sequel, Superfreakonomics, had a section devoted to the suggestion that global warming was going to be imposssible to solve via cutting carbon emissions (with renewable energy sources) and so we should focus our efforts on geoengineering schemes instead. RealClimate has a well-written post up today showing just how sloppy the Superfreakonomics authors' thinking on this issue is.

Labels: books, climate change, global warming, politics, tech

Whew! A busy day at the Geological Society of America meeting in Portland, Oregon. I started off the day in the two-year-college session, culminating (for me, anyhow) in my talk about the role that field trips play in my geology classes at NOVA. I believe in spirited presentations, so I moved away from the lecturn and spoke extemporaneously about my images and data, and the talk was well-received by the audience -- or at least that portion that chose to tell me what they thought. After the talk, I was really tired out (I hadn't realized I was stressing about the talk, but apparently I must have been.) I went back to the hotel and took a shower, dealt with some mortgage stuff (I'm buying a condo in DC), and then semi-refreshed, headed back to the fray at the Convention Center.

I've met another several geobloggers: Brian Romans and Kim Hannula. Geoblogger Lockwood Dewitt sent me a rock (natrolite in calcite! likely from a pillow basalt!) via roaming geoblogger "Silver Fox." Cool. I dig it. I had some people come up to me out of the blue and tell me that they read this blog, and that is super cool to hear. Thanks!

In the afternoon, I went to a few sessions about volcanism and the end-Permian extinction, history-of-geology, and I forget what else.

In the late afternoon, the beer began flowing. I started off at the W.W. Norton publishing company's beer bash, where I brushed shoulders with Walter Alvarez, met the author of my Physical Geology textbook, Steve Marshak, and chatted at length with Bob Lillie of Oregon State University about getting the National Park Service better educated about their geological resources. Then it was off to the AGI reception, where I won a bottle of wine and got to chat with David Williams, author of Stories In Stone. Meg Sever, the editor of EARTH, with whom I've e-mailed a zillion times, but never met. Turns out Meg went to William & Mary, like me (and Jessica Ball, also at the AGI reception), so the three of us trooped upstairs to the William & Mary alumni reception. It was good to see Brent Owens, Heather McDonald, and Chuck Bailey there, as well as other W&M geology grads (including Graham, who reads this blog! Hi Graham!).

The evening's final event was the much-ballyhooed geoblogger's meet-up. At 8pm, about fifteen of us assembled at Tugboat Brewing Company, a cozy, charming little pub in downtown Portland. Every time someone walked through the door, a rousing, "Yeeeaaaahhh!!!" cheer went up. And every time someone left, they got booed! It was terrific fun meeting everyone that I've had these online geoblogging relationships with over the past ~1.5 years, and I think a good time was had by all. I'll put some photos up later... [Other online reminiscences about the meetup: Chuck and Jessica.]

Labels: books, geology, meetings, national parks, nova, oregon

Somehow, I've gotten a lot of reading done over the past six months. A lot of this reading consisted of books on climate change -- more on that in another post. But I wanted to share my thoughts on a few other books:

Sand - Michael Welland [blog]

Awesome. The perfect little book for those interested in geology. Looking at the world through a grain of sand. Very diverse, chock full of fascinating stuff that appeals to the intellect on many levels. Smart, erudite, funny. Recommended.

Stories In Stone - David Williams [blog]

A good read; like reading a compliation of feature stories in EARTH magazine; however, unlike Sand, no single unifying theme ties them all together. The overall idea is that the rocks we make our buildings out of have interesting backstories. The book is organized into a dozen or so chapters, each about a different building stone. Some are common (Indiana limestone), some are rare (petrified wood). All have got interesting stuff going on in terms of their geological history, human tie-ins, and architectural tweaks. If you live or work in a building, it's worth reading.

Your Inner Fish - Neil Shubin

Superb. Learned a ton about evolution's lingering fingerprints on our bodily blueprint. Did you know that the nerve which controls our larynx runs from the brain to the larynx via the heart? This unintelligent design is a vestige of the way our body develops from an embryo -- and can be traced directly to fish. There wasn't as much about Tiktaalik in here as I expected, but just enough to make the point.

Bones, Rocks, and Stars - Chris Turney [blog]

Really interesting, though the chapter on King Arthur didn't do much for me. But the rest of it is a great introduction to the various ways we figure out how old things are (Subtitle: "The Science of When Things Happened"). Great chapters on the orbital forcing of ice ages, carbon dating of Homo florensis (which Turney did), and Pleistocene megafauna extinctions. Recommended.

Glacial Lake Missoula - David Alt

Not so great as a book. Really more of a field guide, but not even all that great on that level. It essentially traces the geologic evidence of GLM "and its humongous floods" from Missoula north, west, south, and west again -- the path of the big Channeled Scablands-forming megafloods. A good resource for specific outcrops that illustrate parts of our understanding of this huge event, but not especially enjoyable to read.

Bretz's Flood - John Soennichsen

Much better -- a lovely biography of J. Harlan Bretz, the geologist from the University of Chicago who first documented the Channeled Scablands and deduced that they must have been carved by an enormous flood. A perfect little portrait of an academic's career. Bretz appears to have been quite a character! I really enjoyed the perspective this gave me on the whole "megaflood" idea.

Labels: books, evolution, floods, geologic time, sediment

Yet five more of the maps I scanned from my recently-entered-the-public-domain copy of Vernon Quinn's book A Picture Map Geography of the United States. As before, clicking on the image will take you to a bigger version of the map. Enjoy!

Labels: art, books, connecticut, maps, maryland, new york, oregon, washington

Five more of the maps I scanned from my recently-entered-the-public-domain copy of Vernon Quinn's book A Picture Map Geography of the United States. As before, clicking on the image will take you to a bigger version of the map. Enjoy!

Labels: art, books, california, georgia, idaho, maps, utah, west virginia

Labels: art, books, colorado, indiana, louisiana, maps, michigan, new mexico

Labels: arizona, art, books, delaware, maine, maps, new jersey, pennsylvania

This semester, I employed a new tool in teaching structural geology. Built by NOVA's uber-clever engineering guru Rob Woodke, this is the Butter Buster. The idea came from Structural Geology of Rocks and Regions by Davis & Reynolds, the text I use for teaching structure, and was recommended as a crowd pleaser by Aaron Martin, the structural geologist at the University of Maryland.

So what's the deal? The deal is that materials like rocks behave differently if they are cold or if they are warm. (They also behave differently if they are under high or low pressure, and if strain is applied quickly or slowly, etc., but here our independent variable was temperature).

We can demonstrate this difference by creating an analogy between rocks and a more familar substance, butter. The butter buster creates a fault/shear zone of adjustable width, and displaces the two ends of the butter in opposite directions. If it's cold, it breaks. If it's warm, it flows. Ta-da!

Check it out...

Cold:


Room temperature:


Warm:

Labels: analogies, books, structure, teaching

One interesting thing I learned when reading Tyler Volk's CO2 Rising deserves a blog post of its own: It's called the Suess effect, after the Austrian chemist Hans Suess, a fellow who I've quoted here before. The basic idea here is that by burning fossil fuels (oxidizing fossil carbon), we are diluting the amount of ¹⁴C in the atmosphere of our planet. As you may be aware, ¹⁴C is produced continuously in the upper reaches of our atmosphere as nitrogen atoms get bombarded by solar particles (specifically, thermal neutrons). Hydrogen is a byproduct of the reaction. It goes something like this:
This ¹⁴C isn't stable over the geologic long-term: it spontaneously breaks down, via radioactive decay, with a half-life of about 5730 years. This property means that ¹⁴C is really useful for dating organic matter of the relatively recent geologic past, a time of particular interest to us, since that's when our species developed its distinctive cultures. But the short half-life means that by the time 60,000 years or so have gone by, there's so little left that it's no longer useful for radiometric dating.

Of course, most of the fossil fuels we use are far older than 60,000 years [A lot of the coal we use formed during the Carboniferous, about 360-299 million years ago], so their store of ¹⁴C long ago reverted to ¹⁴N. When we burn this carbon, we combine it with oxygen and send it into the atmosphere. Isotopically, this fossil carbon looks different from the rest of the carbon in the biosphere.

So overtime, as we burn low-¹⁴C fossil fuels, we would expect to see the total atmospheric ratio of ¹⁴C to other isotopes of carbon decrease. The carbon in the atomsphere becomes more and more enriched in ¹³C and ¹²C as low-¹⁴C coal, oil, and natural gas get oxidized.

In other words, the abundance ratios of these different isotopes of carbon provide a fingerprint for where all that extra carbon dioxide is coming from: it has to be from ¹⁴C-depleted sources, like old carbonaceous sedimentary deposits. For a nice graph illustrating this, click here.

Last thing: The Suess effect holds up only until the early 1950s because after that extra ¹⁴C produced during nuclear bomb testing starts to build up again, skewing the overall trend.

See also this image. (A high-res slide explaining the phenomenon, and detailing different natural repositories of carbon isotope data.)

References:

P.P. Tans, A.F.M. de Jong, and W.G. Mook. "Natural atmospheric ¹⁴C variation and the Suess effect," Nature 280, 826 - 828 (30 August 1979); doi:10.1038/280826a0

Labels: books, CO2, coal, isotopes, oil

When I started writing this post, I had just finished reading Tyler Volk's book CO2 Rising. Now it's been more than a month, and it's time to get this post up online. The author has kindly granted me permission to reproduce some of the images from the book.

CO2 Rising has got some stuff that sets it apart from other global warming books.

To start with, it's more focused on helping readers understand the carbon cycle rather than outright climate science. To do this, Volk employs a heurisitic device of naming certain carbon atoms. He names one 'Dave' (in tribute to Dave Keeling, who established the atmospheric CO2 observatory on Mauna Loa). Dave gets washed out of limestone and into the sea, he diffuses into the air, he gets sucked into a plant stoma and locked up in plant sugar. He gets fermented in a batch of beer, and drunk by the author, then oxidized and diffuses across the lung membrane and is exhaled back into the atmosphere, and so on. There are three other carbon atoms who also get names, and the reader gets to follow them on their adventures through the biosphere over tens of thousands of years. Some have been locked up in fossil fuel deposits for millions of years.

While I've heard some dismiss this narrative technique as a gimmick, I liked it. It drives home the point that carbon atoms "live" forever, and are simply jumping from carbon reservoir to reservoir through chemical reactions and physical flow. Bonds form and are broken. Energy is absorbed, energy is released. Now Dave is in a coccolithophore, now he's in a tree, now he's being oxidized in a cooking fire. You really get a sense of the complexity and the limits of the carbon cycle.

After these physical pathways are established, the latter half of the book explores the manifestations of accumulating carbon dioxide in the world. The reader, with their new sense of the robust & complicated nature of the carbon cycle, can start looking at the problem of anthropogenic climate change.

I was particularly impressed with Volk's pedagogical style by "zooming out" from a series of graphs of carbon dioxide, granting a tremendous perspective on how out-of-whack our modern CO2 concentrations really are. He does this by starting with the present day and backing out further and further into the past. The saga begins with the familiar Mauna Loa curve:


Then he puts that in perspective by showing CO2 data from Law Dome ice, which overlaps with Mauna Loa:


...But Law Dome's record goes back further than that:


...And where Law Dome's record ends, the ice of Taylor Dome takes over:


...And it takes us back further still:


Finally, we get to Vostok's record, which takes us back (in this graph) 400, 000 years:


I think that's a pretty impressive way of presenting this data -- building it out bit by bit, starting with the familiar and then going waaaaaaaaaayyyy back into the past.

All in all, I really enjoyed the book. I recommend that you read it. Say hi to 'Dave' for me!

Labels: books, climate change, CO2, global warming

Here's what I've managed to read over the past month or so...

Al Gore's The Assault on Reason:
A scholarly work on the declining role of thoughtful, logical, reflective, searching thinking in the public sphere. Gore remains upbeat but flummoxed as to how many people buy into evidenceless claims, and pins a lot of the blame on TV, which is "a one-way medium." Gore's current gig (other than promoting awareness of climate change issues) is running a TV channel where users submit content, and he sees this as the modern-day equivalent to revolutionary-era pamphleteering. If Thomas Paine were alive today, Gore thinks he would opt to express himself on Current TV. The book is a good read (I'm a very sympathetic reader, it should be noted -- my opinion is that if the 2000 election had gone to Gore, the world would be in a much better place), but its pages feel a little dated, written as they were during the fifth/sixth years of the G.W. Bush presidency. There's an ominous undercurrent that has evaporated a bit in the present Obama era. Doubtless the book would read differently if it were penned today.

Alan Moore's & Dave Gibbons' Watchmen:
The graphic novel which provided the inspiration (and pretty much the screenplay/storyboards) for the recent blockbuster movie of the same name. I haven't read a comic book in a long time, and a graphic novel... Well, I think this was the first. [Does that make it the 'best graphic novel I've ever read'?] It was really entertaining and full of the same interwoven set of plot elements and 'easter eggs' that makes watching the television show LOST such an intricate, engaging exercise. If you're not already familiar with it, it envisions an alternate 1985 where Richard Nixon is still president of the US, and we're on the brink of nuclear war with the Soviet Union, and costumed 'super'heroes (really just masked 'adventurers') are outlawed. Some of these 'heroes' are really psychos, and others merely emotionally/psychologically damaged goods. It's interesting to see these do-gooders wrestle with life's tricky bits, while simultaneously attempting to avert World War III.

I also read Tyler Volk's CO2 Rising, but that one deserves a blog post of its own to discuss... Stay tuned.

Labels: art, books, movies, politics

Amazing stuff...



I found out about this incredible art via Michael Welland's book Sand: the Never-Ending Story, which I just finished reading. [The book is superb, and everyone should read it, but more on that later.] For the moment, just watch this incredible thing. This is art, real art: simple in the extreme on one hand (a ball rolling through sand), but complex in the extreme on the other hand (the two dimensional images that emerge and evolve over time are terrific), and its underlain by some reasonably complex computing. Here's artist Bruce Shapiro talking about his work:



Like what you see? Then download this video and watch it. Showing the "Sisyphus III" sand plotter in time lapse photography set to music, you really get a sense of what this thing is capable of. ...Mind-blowingly cool.

Labels: art, books, sediment

While completing an Amazon impluse buy triggered by the "Climate Sale" post at The Way Things Break, I noticed a clever book cover:

Whoever designed that deserves a bonus. Pretty clever.

Labels: art, blogs, books, climate change, global warming, websites

Another book I read over the winter break was Canyon Solitude, by Patricia C. McCairen. It's a travel book about one woman's solo journey down the Colorado River through the Grand Canyon. It's one of those books that derives its structure from a journey, but it includes plenty of asides, mainly about the author's longer-term personal journey through life. It's rich in a kind of feminine soul-searching which may appeal to female readers, but as a male, I kind of didn't "get" that part. That being said, I'm a fan of travel books, and it was a pleasant enough read. I think it resonated more with me than it would with the average bear because I spent a week on the same journey this summer. Overall, I'd give it 3 stars out of 5 possible.

Here's a link to the book on Amazon.

Labels: arizona, books, grand canyon

From Greenfyres, via Tamino: "Sherlock Holmes and case of the climate bandwagon." Well worth a read, if you like satire and the writings of Mr. Arthur Conan Doyle.

Labels: blogs, books, climate change, global warming, humor

After yesterday's review of Ancient Landscapes of the Colorado Plateau, author Wayne Ranney left a comment here that alerted me to his blog, which the geoblogosphere may be interested in:

Labels: blogs, books

Over the winter break, I read the new book Ancient Landscapes of the Colorado Plateau, by Ron Blakey & Wayne Ranney. This is an excellent read, and a terrific introduction to the geologic history of one the world's most dramatic landscapes. Blakey's maps have been featured on this blog before, and he has been kind enough to allow me to modify some for use on my field course websites (like here and here and here). The book goes through geologic time and makes extensive use of beautiful paleogeographic maps to reveal the story of mountain-building, transgression, regression, sand-dunes, faulting, volcanism, and erosion that characterizes the Colorado Plateau. It's not just paleogeographic maps, by the way: there are also plenty of shots of fossils, Colorado Plateau landscapes, and comparable modern depositional environments to enliven the story. It's a graphic story, well told with excellent graphics. I recommend you get yourself a copy if you've ever been to the Colorado Plateau, or if you ever plan on going there.

Find the book: On Amazon ... At the NOVA library

Labels: arizona, art, books, colorado, maps, new mexico, utah

John McPhee and Eldridge Moores give a talk at UC Davis...

Labels: books, geologists, plate tectonics

The author Michael Crichton died yesterday. He gave us Jurassic Park; He also wrote a novel based on the idea that global warming was a hoax (State of Fear). A mixed bag, but he'll be remembered for Jurassic Park. I've read everything he's written except for the global warming book. My favorite was non-fiction: Travels. Check it out.

NY Times obituary.

Labels: books, dinosaurs, global warming

In preparation for my time out west this summer, my friend Michelle loaned me her copy of Cruisin' the Fossil Freeway, by Kirk Johnson and Ray Troll. It's a great read, and it's got me really psyched to start driving around the west, looking at geology. It also makes me wish for an informed local guide to clue me in to good outcrops.

I really liked this book. Johnson, a paleontologist with the Denver Museum of Nature & Science, narrates a 5,000-mile roadtrip travelogue about zipping around the western U.S. in search of fossils. Joining Johnson is Troll, a celebrated artist who makes clever art in several media. The book is light-hearted, well-informed, funny, and relaxed. I really liked it, and would recommend it to anyone with an interest in natural history, fossils, roadtripping, or Ray Troll's art.

Coincidentally, Geotimes reviewed the book in their May issue.
...And NPR beat them to it last fall.

Labels: books, colorado, fossils, kansas, nebraska, wyoming

Last week, my friend Michelle loaned me her copy of Farewell, My Subaru, a humorous account of a year spent trying to live locally. The author, Doug Fine, buys a ranch in New Mexico, then converts it to solar power and solar heated water, and raises goats and vegetables. And, yes, he trades in his Subaru for a R.O.A.T. (Ridiculously Oversized American Truck), which runs on vegetable oil. Along the way, he has lots of mishaps (many involving the goats) and finds love, happiness, and satisfaction. In general, he has a nice reflective time of it, accumulating enough experiences and insight to warrant a book. He's also got a great sense of humor. Recommended.

Labels: books, environmental, oil

This one's a good one to assign to Historical Geology students who don't have time to read The Map That Changed The World. It's part of the series "On the Shoulders of Giants" by NASA's Earth Observatory: William Smith.

I love the way these pages are laid out: a single column of text with illustrations of different sizes and dimensions interspersed with the content. It's like a Dorling Kindersley book. NASA must have some good web designers on the payroll.

Labels: books, fossils, geologists, history, stratigraphy

Periodically I post book reviews on this blog of geology-relevant books. I haven't done too many of these since I started the blog because it's been the spring semester, and that means I've been too busy to read. But now that the summer's here, I've got a bit more time. Today's tome is Last Child in the Woods, by Richard Louv.

The theme of the book is "nature deficit disorder," a condition the author loosely defines as adults not caring about the natural world because they never spent any time outside as children. Setting aside the quasi-disease-sounding name (which Louv acknowledges as being iffy), it's pretty much a priori that if you don't know something, you don't value it. When children spend their time playing video games instead of romping in nature, they end up caring about the one and not about the other. Last Child gets a little tedious making this point over and over: do you really need a whole book to explain that?

In the course of that protracted treatment, however, Louv brings up some good points. For instance, natural play has been effectively "criminalized" in our (U.S.) litigious society. We care so much for our kids' safety that we prevent them from doing anything dangerous. He also makes the point that nature education has dropped off, resulting in lower knowedge about natural systems.

Some passages rang particularly true for me. On page 139, Louv describes an observation by Robert Stebbins, an old-school naturalist (and professor emeritus at the Museum of Vertebrate Zoology at the University of California, Berkeley). Stebbins has been going out to the California desert for many years studying reptiles and other critters. The rise of ATV (all-terrain vehicle) recreation in his study sites has obliterated the local wildlife. He found that 90% of invertebrate life had been destroyed in popular ATV areas. I'll quote Louv quoting Stebbins here:

What upset him most was not the destruction that had already occurred, but the devastation yet to come and the waning sense of awe -- or simple respect -- toward nture that he sensed in each successive generation. "One time I was out watching the ATVs. I saw these two little boys trudging up a dune. I went running after them. I wanted to ask why they weren't riding machines -- maybe they were looking for something else out there. They said their trail bikes were broken. I asked if they knew what was out there in the desert, if they had seen any lizards. 'Yeah,' one of them said, 'But lizards just run away.' These kids were bored, uninterested. If only they knew."

Labels: books, environmental, teaching

Over the first half of the semester, I've been reading Vaclav Smil's comprehensive book The Earth's Biosphere. It's an incredible work of scholarship, and I recommend it to anyone with a solid foundational understanding of both biology and geology who's ready for "the big picture": an overall review which will give contextual perspective on each of the details of how the living portion of our planet works. It's a remarkable book, really. It covers so much, in such a precise, well-written manner, that it makes my head spin. It has forty pages of references (in small type)! As an example of the multidisciplinary nature of the book, I offer the following graphic from page 134:

In one image, Smil integrates information about seven variables: clay varieties, latitude, biome type, depth of weathering in the crust, precipitation, temperature, and evaporation! That's an incredible accompishment graphically, but he does the same thing in just about every sentence.

I read the book originally because a potential student recommended it as providing a "balanced" look at climate change. Curious to see what that meant, I checked it out of the library here on campus, and read it. It has an excellent and comprehensive scientific discussion of climate change, with a particular focus on how the Earth's biosphere will effect it, and be effected by it.

I feel obliged to give an example of something I learned, so here's amazing fact #3546 from the book: photosynthesis is really inefficient! Plants vary in how photosynthetically efficient they are, but the values range from plants that capture 0.1% of incoming solar radiation to the really efficient ones, which max out at capturing about 2% of incoming solar radiation. That's so not efficient! I had no idea.

Of course, no book is perfect, and I'll offer two complaints about The Earth's Biosphere: (1) A general theme is woven throughout the book of examining the work of neglected Russian scientist Vladimir Vernadsky, who made critical advances to our understanding of the biosphere, but hasn't gotten enough credit. Smil goes overboard in giving Vernadsky his due: it's Vernadsky this, Vernadsky that, every couple of pages through the whole book. I got sick of reading about him, and wished Smil could stick to the (excellent, fascinating) science, divorced from the persons who wrought it. (2) Every now and again, he threw in a superflous graphic, like this one:

Is the fish really supposed to be ~16 m tall? What's the point of this graphic anyhow? To show that fish live below the ice? Seems to me you could just say so. (Plus, the graphic needs the scientific name italicized, as in the caption.) I don't mean to snipe -- most of the book is super, but stuff like this irritates me. A fly in the ointment, I guess. The book's worth reading regardless.

Labels: books, climate change, global warming

The New York Times reviewed a new book about birdwatching this weekend. If you can agree with the statement, "I can't think of any activity that more fully captures what it means to be human in the modern world than watching birds," then you might enjoy Jonathan Rosen's The Life of the Skies. The review (by Robert Sullivan, who wrote the book Rats, which has the best cover of any book ever) is astonishingly well-connected (in the Internet sense of the word): it weaves in allusions to Robert Frost, Jack Kerouac, and Theodore Roosevelt. I haven't read The Life of Skies yet, but it is now on my list.

I love running into birds. The other morning, when it was relatively warm, Casey and I went for a walk in the Zoo, and saw a pair of red-shouldered hawks (wild, not caged) building a nest in one of the big old orthern red oak trees there. It was cool to see: they were collecting sticks several feet long and doing short fly-hops through the canopy as they maneuvered into their nest site. Today, we went back and looked for them again, but there weren't there. Maybe out hunting?

In DC, the winter weather persists. It was cold and windy this weekend, and daylight savings time didn't help much. Soon, (very soon, I hope), the weather will warm and the birds will return. Right now, there's nothing to look at except rocks, cold rocks. Some of my Honors students and I got out in the field today to do measurements for their various projects, and when the sun was out, it was pretty nice. Still fleece and jeans weather, but you can sense spring is on the way.

Labels: birdies, books, nova, teaching

In preparation for this summer's rafting trip down the Grand Canyon with my father & two brothers, I checked out the book An Introduction to Grand Canyon Geology from the NOVA library. The author is L. Greer Price. It's a slim little book, in full color, with lots of little boxes inserted amid the main text. These boxes explore smaller subtopics like stromatolites or rock color. The main text emphasizes the chronological sequence of steps to create the bedrock of the Canyon, and then a detailed discussion of how rock structure and erosional effects combine to carve the land into a shape as varied as the Grand Canyon. It's a book a lot like the one I'm working on for the C&O Canal.

I've visited the Grand Canyon four times, so I've managed to get a lot of the upper stratigraphy down. I picked up this book to bulk up my understanding of the deeper gorge (where my family & I will be spending our time in June). While a lot of the book was geological boiler-plate about plate tectonics and superposition, I learned some new details. For instance, I had no idea the Cenozoic was represented at all in the Canyon, but apparently the remains ("still pungent") of a Shasta Ground Sloth were discovered in Rampart Cave (a cave in the Muav Limestone) in the western Canyon.

The writing style is balanced. I could see how the author struggled with being technically accurate but also accessible to the wide audience he was writing for: the Mazatzal Orogeny (~1.7 Ga) is described, but it's not called the "Mazatzal Orogeny." Another example would be in describing Mesozoic subduction on the west coast, Greer swaps out the technically-correct name Farallon plate for the more recognizable "Pacific" plate, even if that's not technically correct.

The book is short (59 pages), and it's 50% pictures -- an easy read in an afternoon.

Labels: books, grand canyon

Over the winter break, I finished reading the textbook Petrology by Harvey Blatt, Robert Tracy, and Brent Owens. "Petrology" is the branch of geology that is the study of rocks. (A lot of people coming into an introductory geology class for the first time think that geology is the study of rocks, but of course it is not. Geology is the study of the planet Earth.) This is a sure sign of me being a geology geek, but I really enjoyed it. The igneous section was least enlightening, but I really enjoyed the sedimentary section and the metamorphic section. I learned a bunch of new things about limestones, bentonites, the Barrovian sequence of metamorphism, and other fun stuff. It's in the Annandale branch of the NOVA library. If you've had at least one semester of geology and want to learn more about a specific rock type, I recommend it.

Labels: books, geology

The National Academies of Science released a new book yesterday about evolution. Aimed at the layperson, it explores the molecular, organismal, and fossil evidence in favor of evolution. The book suggests that accepting this evidence does not require losing one's religious faith, but instead that the two are compatible ways of viewing the world. The book is entitled "Science, Evolution, and Creationism." A PDF brochure offering an overview of the book is here, and the book can be ordered online here. Perhaps as a sign of things to come, the entire book is also available online, and you can access it here.

Labels: books, evolution