Saturday, October 2, 2010
Sometimes, One NEEDS To Be A Grammar Nazi
Saturd80's
Adam and the Ants, Stand and Deliver:
Psychedelic Furs, Pretty in Pink:
OMD, Electricity:
Psychedelic Furs, Pretty in Pink:
OMD, Electricity:
Friday, October 1, 2010
Thursday, September 30, 2010
Accretionary Wedge #27: Important Geological Experiences
NOTE: If you submitted a post for this AW, and don't see it here (or know of one that I didn't include) please leave a comment and a link. I'm almost certain I lost at least one in writing this up, maybe more, and it's quite possible I simply missed others. Thanks for your help. I'll leave this note up for a while, then clip it off when I cross post to the AW blog in a few weeks.
A few weeks back I suggested a topic for the next AW, important geological experiences:
It has left me with something of a problem- how to organize it? After reading the posts, I went back though and loosely organized them into somewhat arbitrary themes that stuck out in my mind: "New faces, New places," "Thinking it through, Working it out," "The Real World," "Limitations," and "Field Camp." Many people's experiences included aspects of two or more of these themes, so I have pigeon-holed mercilessly. Without further ado, here are the submissions.
(From here- link #1 under "Photographs-" inspired by Coconino's post)
The first submission was from a high school friend, Steve, who is not a blogger or a geologist, but whose geological future looks somewhat ominous:
A central theme of geology- one I sometimes wonder if we spend enough time discussing explicitly- is developing stories, narratives and explanations for how something came to be. It can be stressful when facing this imperative the first few times, though as we'll see in a later section, geologists learn to cope.
(The Far Side, by Gary Larson; picture from here, inspired by the coincidences and others that can lead us to the conclusions we claim as our own)
Geology Happens reminded me of a post from early summer of 2009, when he realized that landscaping gravel was full of familiar rocks, leading him to recall how
The experience I chose also involved the stress of feeling under pressure to come up with a plausible, hopefully convincing, story for how some rocks that seemed out of place came to be where they were.
In the academic study of science education, there is a substantial body of literature on the phenomenon of "classroom science," the perception in students' minds that what they're being asked to learn is how the classroom world works... which may have little or no bearing on how the rest of the world works. Though field experiences have already made a number of appearances thus far, some of the cases seemed to warrant an independent category, of simply witnessing and confronting "the real world" as an experience in and of itself, with the pressure to learn and/or perform fading to inconsequential.
Above, the youngest geoblogger, Sam, who writes with her dad at Geology Blues, posts a delightful photo of herself at Devil's Tower, Wyoming. From one geoblogger to another, a high compliment: you rock, Sam!
I really doubt that geology is unique in the way that its students confront "fail" on such a regular basis, but there does seem to be an unusual acceptance among its practitioners that we are, at the very least, occasionally not going to find an answer that stands up to testing, or even that satisfies us in the short term. If this category seems derogatory, you probably haven't spent much time doing geology.
(Found here, with the comment "Truer words were never spoken..." Except in geology, a better caption might be "It's better to know and accept your limitations than to be eulogized.")
CB Dawson of Point Source gets at a perennial problem in many disciplines: techniques and technologies have been developed to simplify doing whatever it is you want to do, but the devil is in the details. If you don't know what's happening in the process of simplification, can you say you know what's happening at all?
The final category for this month's wedge is "Field Camp." As I said at the outset, there is a lot of overlap in the themes I picked out to organize these posts, and a number of others already written up might fit here as well. These are ones that struck me as really getting at the essence of the field camp experience.
John Wesley Powell's first camp at Green River, Wyoming, from the US National Archives (entry #11, here).
Silver Fox of Looking For Detachment describes the events that fortuitously allowed her to return to her beloved west, instead of "asentence
I just realized a bit ago that I haven't actually put up a notification of the next Accretionary Wedge at the AW Blog (Now remedied), though I have here at OTI and on Twitter. But just as a reminder, Matt has kindly offered to host October's AW, with the theme of "Deskcrops." See the link for full details, and leave comments and links to your submissions at Matt's call for posts.
A few weeks back I suggested a topic for the next AW, important geological experiences:
It may (or may not) be something that led you to the discipline , or a class, or a work experience, or a field experience. It might have been a puzzle or problem solved, or job landed, a degree completed. Perhaps it was something else entirely. It could have been an awful, disastrous experience from which you learned an important lesson. Maybe it's still in your future- something you're looking forward to. Additionally, explain why it was important.The response has been nothing short of overwhelming.
It has left me with something of a problem- how to organize it? After reading the posts, I went back though and loosely organized them into somewhat arbitrary themes that stuck out in my mind: "New faces, New places," "Thinking it through, Working it out," "The Real World," "Limitations," and "Field Camp." Many people's experiences included aspects of two or more of these themes, so I have pigeon-holed mercilessly. Without further ado, here are the submissions.
New faces, New places
This theme developed around the pattern of people engaging with landscapes, people and cultures that were formerly new or even alien to them, and finding wonder.The first submission was from a high school friend, Steve, who is not a blogger or a geologist, but whose geological future looks somewhat ominous:
I have a candidate, a twofer: a young French friend of ours was in Chile with her boyfriend (now husband) when the recent big earthquake struck, staying in the same beach resort where some of the most dramatic photos were taken, and then, a couple weeks later, she was in Paris when the volcano in Iceland blew its top,and as a result she was one of many left stranded, unable to return home, because of the volcanic ash. Personally, it makes me a little nervous that she's now living in Albuquerque, close to me and mine, and close to the Valles Caldera...Michael Welland at Through the Sandglass had the experience of getting gnashed between the grinding plates of geology's great paradigm shift in Innocent Abroad.
For my presentation I brought out several plate reconstruction graphics that I had hauled across the Atlantic; I put these up on the wall of the seminar room, and launched into the story – the Cambridge (UK) edition, that is. And then it happened. The imposing voice of Bernie Kummel interrupted my narration – and he was coming down on me like a proverbial ton of bricks. A sense of shock and horror came over me: Bernie Kummel, the Bernie Kummel, didn’t believe a word I was saying.Ian Stimpson of Hypo-theses fame relates a (mostly) solitary adventure in a foreign land, and brings to our attention another emergent theme among geologists: the stress of feeling alone, but in some way obligated to find "the answer."
Prior to this our mapping training was done as buddy pairs but here I was on my own. We wouldn’t be allowed by health and safety regulations to do this today, which is a real shame because it was a wonderful experience. It was just me against the rock. I had to sort things out for myself. It took me about four weeks to work out why in one part of the area the bedding/cleavage relationship was telling me that the beds were upside-down where as I knew from the stratigraphy that they were the right-way up. It was a struggle, but I cracked it – myself.The next couple of entries highlight the disproportional influence just one or two mentors who care can have on a young geologist's life path. History of Geology's Dave Bressan discusses how getting away from the dry structure of a discipline, and focusing on enthusiasm can make a world of difference.
This changed suddenly; the next lecture was hold by a new visiting lecturer - with a complete different approach. Even if the step by step procedure of plant determination was inevitable, the mood was noticeably better, there was an introduction at the beginning of the lessons about the characteristics of the plants we should observe, and inevitable errors perpetuated by us beginners were not ridiculed, but explained and resolved.And in what I nominate as one of the most deeply moving geologic experiences of all time (of all time!) Matri describes her transition into geology under the guidance of a professor who truly understands what it means to be a mentor, in "Of Honest Teachers and Precious Rock Hammers." My sniffles and watery eyes are just allergies. Seriously.
...through the course of the semester, Professor Chen noticed this curiosity and indecision on my part, and went out of his way to convince me to enroll in UIUC’s geoscience program of study. During office hours, he would honestly and tirelessly list all of the degree’s challenges and, like every good Asian parent, none of its rewards. That mineralogy required chemistry and optics, being able to identify thousands of minerals and late hours in the lab. That the geology curriculum required geophysics which in turn needed linear algebra and differential equations and three physics classes including electricity & magnetism. That structural geology was difficult for many but I should take it the following semester when it was offered. That much field and lab work was required on weekends. That distinction and honors in the program (and he expected no less) came only with undergraduate research and a thesis. That beyond here were graduate school, more graduate school and, maybe some day, a postdoctoral position and then the tenure track. Was this man insane?Coconino of Ordinary High Water Mark discusses a youthful memory from another land and a shocking realization that "impossible" landscapes do exist- an experience I know I've had, and which I suspect most of us share.
It blew my mind that day, that mountains did "grow" that way, that the art I had seen was not all wrong. I looked at those slides with wonder and awe. And they inspired a love of landforms and earth processes I've never lost.Kyle House and I share this much: we moved to the Pacific Northwest, and if not overwhelmed by what we found, we were certainly whelmed, fair and square.
...when you are a typical kid growing up in Texas and Oklahoma, you think the only mountains in the country are in Colorado. Then, if you take a trip to Seattle on a clear day and see the unthinkably huge, ice-laden edifice of Mt. Ranier looming over the city like no mountain you have ever seen in your short life, all bets are off. Everything changes. The Cascades blew my mind. Surprisingly (or not), I was such a slacker in 1980 that Mt. St. Helens never registered for me (even though I was 15 at the time). But once I got to western Washington only three years later, my life changed forever. I was completely enthralled by the scenery and the juxtaposition of ice-clad volcanoes and the ocean.Anne of Highly Allochthonous describes a flood in the middle of the Australian desert. Desert downpours and flooding have fascinated me since my first visit to the Grand Canyon, and I'm a little jealous: I still haven't witnessed a good rainstorm in the desert. On the other hand, I have to admit some of her description gives me a case of the willies.
But while the floodwaters had passed in Alice, there was still LOTS of water in the desert. As desert roads aren’t always equipped with bridges, there were several places where the vehicles had to ford slow-moving or ponded water. Even in college, I was enough of a river rat to know that driving across a flooded roadway is a great way to get yourself killed and I remember lots of consternation at the prospect of the water crossing pictured below. But we were literally in the middle of nowhere so my options for abandoning the trip were limited and after watching at least a dozen other vehicles ford the water, my friends and I got back on our bus and safely made it across the remnants of Rosita’s rain.
Thinking it through, Working it out
A central theme of geology- one I sometimes wonder if we spend enough time discussing explicitly- is developing stories, narratives and explanations for how something came to be. It can be stressful when facing this imperative the first few times, though as we'll see in a later section, geologists learn to cope.
Geology Happens reminded me of a post from early summer of 2009, when he realized that landscaping gravel was full of familiar rocks, leading him to recall how
...with some simple tools I could interpret a rock, a outcrop, a road cut and even a mountain range. This idea shook me up. Here is something that happened a long time ago and with a few rules of physics I could construct a story about the origins of a landform...I was hooked....or a truckload of river gravel, for that matter!
The experience I chose also involved the stress of feeling under pressure to come up with a plausible, hopefully convincing, story for how some rocks that seemed out of place came to be where they were.
In our soil pits, from which we collected samples and water that had leached through the top meter of the soil, we kept finding these clusters of basalt cobbles, about fist-sized. They too were deeply weathered, but under a centimeter or two of clay, quite fresh. Judging by the weathered surface, they were pretty angular; if they had been transported, it wasn't far. Without thinking much about it, I simply assumed they had moved in by soil creep. It turned out later that creep wasn't a tenable mechanism, because there wasn't enough uphill uphill from our site, and no basalt outcrop either.At Mountain Beltway, Callan presents a reminder of something those of us with years doing geology sometimes forget: what seems simple to the experienced can be troublesome and/or profound to those just getting started. Even something as straight-forward as a first anticline.
Bam! It hit me: I got the idea of an anticline at that point — the idea that a structure like an anticline could be so large that I couldn’t actually see it from my earthbound human-sized perspective, and I could only infer it from detailed measurements of the rock structures. It was a revelation to me: this valley and its surrounding ridges were part of a massive fold. The anticline must have breached in the middle, with the shale eroding away faster than the sandstone, producing a valley flanked by two ridges.Matt Kuchta, who blogs at Research at a Snail's Pace, not only contributes to this month's wedge, but also foreshadows the next, in a post I summarized in my organizational notes as "slickensided lightbulb."
One of the instructors put me on the spot, asking me to speculate on how one might get Ordovician rock sitting next to Precambrian basement rock (skipping all those Cambrian rocks in-between). The outcrop was nothing special - in fact, much of it was covered by talus and vegetation. But, being a minting geologist, I thought for a moment, then looked at the rocks by my feet. There was a chunk of beautifully polished dolomite. "A fault" I said, holding up the sample. I managed to earn "field-trip-brownie-points" not only by providing a reasonable answer, but also a piece of material evidence for my idea.
The Real World
In the academic study of science education, there is a substantial body of literature on the phenomenon of "classroom science," the perception in students' minds that what they're being asked to learn is how the classroom world works... which may have little or no bearing on how the rest of the world works. Though field experiences have already made a number of appearances thus far, some of the cases seemed to warrant an independent category, of simply witnessing and confronting "the real world" as an experience in and of itself, with the pressure to learn and/or perform fading to inconsequential.
My Dad asked me to write what my most interesting experience in geology was. It was when we still lived in Montana, we went to Devils Tower. I thought of it as a big rock that was not a mountain. I liked camping there and waking up to see the sunrise. We took a walk around the base and we saw a huge Pine Snake!Ron Schott at his Geology Home Companion takes an interesting slant on the theme: What is his most important experience, not from a personal perspective, but from the perspective of the earth and its processes? I like his choice.
So many geological processes that we witness at Earth’s surface are destructive (e.g., weathering, erosion, mass wasting, etc.) but how often do we experience Mother Earth renewing herself? I submit that it is not often, yet when considered in the context of the rock cycle, it is of fundamental importance. How much less exciting would geology be on a planet that had long since ceased to be active? Thus I choose for my most “important” geological experience being present at the birth of a rock.I can relate to Planelight's choice of important experience, at Life in Plane Light, since far and away the bulk of the time I've spent in the field has been with learners, not for research or formal purposes, but to try to develop excitement and appreciation (which can only very rarely be assessed afterwards) in students who have chosen to be there.
I enjoy teaching in the classroom and lab, but my favorite part of my job is taking students into the field. Whether it's just down the road or halfway across the country, watching students learn how to look at the ground beneath their feet and the landscape around them to backtrack the geological history of an area is worth the headaches of renting vehicles, planning food that can be cooked over a campstove, and wondering if its going to downpour or snow. To me, going into the field is the reason why I love being a geologist.Why am I not surprised that the choice by Dana, at En Tequila Es Verdad, lyrically captures the sheer awe and wonder that geologists feel in the field? Yes, learning to figure out the story is important, but it's the amazement we experience as we do so that drives us to do it again and again. (Dang, Dana, it's tough to pick just one passage!)
That, my darlings, was the day my young world ended forever, and my old one began. Continental drift went out the window: no more vague images in my mind of stately continents floating slowly about to fetch up gently against one another before drifting apart again like guests at a soiree. The rolling hills around Dewey ceased to be the least-interesting part of the drive between old home and new: I never could pass that way again without thinking of continents going bang up against each other, crushing and transforming rock as they collided. Rocks meant something: they weren't just pretty baubles, but storytellers with a rich store of history to draw on. The world changed fundamentally from era to era, and the past dictated the present. Landscapes weren't just scenery anymore. They were portals to other worlds.
Limitations
I really doubt that geology is unique in the way that its students confront "fail" on such a regular basis, but there does seem to be an unusual acceptance among its practitioners that we are, at the very least, occasionally not going to find an answer that stands up to testing, or even that satisfies us in the short term. If this category seems derogatory, you probably haven't spent much time doing geology.
CB Dawson of Point Source gets at a perennial problem in many disciplines: techniques and technologies have been developed to simplify doing whatever it is you want to do, but the devil is in the details. If you don't know what's happening in the process of simplification, can you say you know what's happening at all?
After the initial glow of “wow, that was easy!” I realized I was far from done. I had so many questions:Jessica (AKA Tuff Cookie) at Magma Cum Laude offers a personal, poignant, and very wise bit of insight for anyone practicing a complex technical skill... especially for the first time:
I had so many questions, but not enough answers! I dug into the software. I learned more about the modeling algorithm. I learned about the variety of settings you could use when running the model. I learned about sensitivity analyses and maximum/minimum versions of the model values.
- How did the model correspond with other geophysical data and local stratigraphy?
- Was the model meaningful?
- Was the model equally valid and reliable in all areas?
- How does the software get from the initial data I provide to the inverse model?
As a freshman, I may have been bright enough that my advisor invited me to come on a trip that was normally restricted to upperclassmen, but I should also have been bright enough to realize my own limitations. That was one of the best things I learned on that trip, and one that's helped me immensely since. If I can take a step back from whatever frustrating problem I'm dealing with at the moment, I can figure out what I tools and knowledge I need to acquire to solve it. That process may be slow and frustrating itself, but it's much better than thinking I know everything (and then finding out, usually in embarrassing ways, that I'm wrong). Come to think of it, this is a great way to look at life in general, not just geology.Julia at Stages of Succession reminds me of a very similar experience I had- though for better or for worse (the outcome was fine in both cases), no one would have had any idea how far afield I was. I'll recount my own story another time, but for now, here's Julia's "Great Cock-up on Great Cockup."
About an hour before our rendezvous point, I was on the saddle between Knott and Great Calva, with Hause Gill and Wiley Gill either side of me. I had intended to go down Wiley Gill, meet up with the track along the Caldew, and stroll back to the car. To this day, I have no idea why I did this, as I was perfectly capable of reading a compass.BTW, I suspect anyone who doesn't have a story similar to Julia's simply hasn't been at it long enough. Yet.
I went the wrong way.
Field Camp
The final category for this month's wedge is "Field Camp." As I said at the outset, there is a lot of overlap in the themes I picked out to organize these posts, and a number of others already written up might fit here as well. These are ones that struck me as really getting at the essence of the field camp experience.
Silver Fox of Looking For Detachment describes the events that fortuitously allowed her to return to her beloved west, instead of "a
Yes! Bright, brilliant geology everywhere, just the way I had always — after growing up near the Sierra Nevada — thought it should be. And rocks besides limestones! And volcanic rocks that weren't old and decrepit greenstones of nearly unimaginable age!In addition to being a classic field camp story, Brian Romans at Clastic Detritus again captures that deer-in-the-headlights, dichotomous feeling of "is that really all there is to it?" combined with "I have no clue what I'm doing; do you really expect me to believe I got this right?"
Last, but most certainly not least, Geotripper Garry Hayes' story isn't of the typical undergrad field camp, which generally comes near the end of a four-year degree, but an intensive and grueling field experience nonetheless: hiking to the bottom, and back out, of the Grand Canyon.
We were going in, spending 4 or 5 days below the rim, checking out each and every one of the layers from top to bottom (and back to the top again).So that winds up this edition of the Accretionary Wedge. It's been both more work and more rewarding than I expected. More work in the sense that I hadn't really thought about how difficult it would be to both organize and give fair play to the tremendously wide set of experiences- a great many shared by most of us, and some almost unique- and the overlapping nature of those experiences. More rewarding than I expected in the sense that working through these recollections has triggered memories of a large number of other geological stories I should tell at some point, picking up on the themes so wonderfully expressed in these entries: sometimes a little self-deprecatingly humorous, sometimes reeking of frustration- or spitting in the face of frustration- but always, always, always anticipating that next moment of awe and wonder, the feelings that drew us to this sublime discipline in the first place.
The trip involved a hike along some of the semi-maintained trails that are not usually a part of the tourist experience. The route down was along the New Hance Trail to the Colorado River, then along the Tonto Platform to Horseshoe Mesa, and then up the steep trail to Grandview Point. The entire journey was a revelation, as we saw the Paleozoic and Proterozoic sedimentary formations up close and personal (miles are meaningless in the canyon; when climbing out, you note what layer you've reached, not a mileage post), explored a copper mine, climbed through two limestone caverns (with ropes and helmets, no less), and even of all things, saw the aurora borealis from our camp on Horseshoe Mesa. I walked out of the canyon a geology major.
I just realized a bit ago that I haven't actually put up a notification of the next Accretionary Wedge at the AW Blog (Now remedied), though I have here at OTI and on Twitter. But just as a reminder, Matt has kindly offered to host October's AW, with the theme of "Deskcrops." See the link for full details, and leave comments and links to your submissions at Matt's call for posts.
Thorsday
Wednesday, September 29, 2010
Columns: Variations on a Meme
Jumping around a bit on the exposition of my field tripping last week, this was our next stop, but I'm not going to fully write it up until I've put together the Accretionary Wedge- I'm planning on starting that as soon as I finish this post, but the columnar meme is still going strong (see end of this post), and I want to contribute a couple more variations.
The above is, I think, the nicest outcrop of pillow basalts I've ever seen- map and further discussion to follow in a future post. So what does this have to do with columnar basalt? As mentioned earlier, columnar jointing forms perpendicular to the surface of cooling. So what if that surface is roughly spherical? Simple:
Radial jointing. I suppose you could think of this feature as "radial columns," though on the scale of pillows, I personally don't. I learned the feature as "radial jointing," and that's the way I think of it. (All pics will get bigger and sharper if clicked upon) Note hand sledge in first picture for scale... I think that's a 4 lb. head, though it has been pounded many, many more than four times. On the other hand, at larger scales, such as this (suspected) filled-in lava tube, I do tend to think of them as "radial columns."
The above is a photo from OregonLive that I blogged about a bit more than a year ago, along the Molalla River, east of Portland.
Others have also pointed out that columns are not necessarily "columns," i.e. up and down. Here are some horizonal columns in a basaltic dike cutting through basaltic breccia. Again, the consistent theme is that the fractures form perpendicular to the surface of cooling. This was from Cape Perpetua, between Yachats (pronounced "yah-hots") and Florence on the Oregon Coast. Though I'll pin down scale more accurately later on, I'm thinking the dike is ~14-16 inches across.
The above is a photo from OregonLive that I blogged about a bit more than a year ago, along the Molalla River, east of Portland.
Wednesday Wednesday
Tuesday, September 28, 2010
I Love Deadlines
"I like the whooshing sound they make as they fly by." It's especially gratifying when it's a deadline I set myself... in this case, the deadline for submissions for AW 27, important geological experiences. Like some other editions of the Wedge, I expected the difficult part would be to pick just one experience- after all, no single experience is enough: there's so much to know and do that "years" is a narrow timeline for feeling anything like competent with respect to geology. "Decades" is a better approximation, and even then, there are important aspects of the science with which each of us will never feel all that comfortable. How to choose one experience out of the hundreds of hours of class and lab time? Thousands of hours reading? Months of accumulated time pondering over (and silently cussing at) outcrops?
So it was with a feeling of surprise that I knew almost immediately which particular day was the one that stood out in my memory. A bit of background is in order: I referred to myself as the eternal undergraduate. I started at OSU in spring of 1980, and graduated in June of 1988. There were simply no classes left in geology that I was allowed to take, and I had sat in on a number of graduate classes. There were plenty of classes in other departments and disciplines that I'd like to have taken, but it was time to move on. The main thing that enabled this, though, was that 20-30 years ago, it was possible to work one's way through school, pay as you went, and come out debt free. That is not the case any more.
I worked in Clinical Pathology in Veterinary Medicine from the beginning of 1981 until summer of 1983, then I landed a job as a lab and field worker with a forest soils research project, where I ended up working until late 1990- even after I graduated, they found ways to keep me on for a while. One of the projects we worked on for years involved looking at the soils and soil water chemistry at Cascade Head. Below is a map of the area, though it doesn't show old 101, which lies a bit east of the new highway. (Screen capture from page 5 of Research Publications of the Cascade Head Experimental Forest and Scenic Area, 1.4 Mb PDF)
(As an aside, if you're ever going through- or even near- Otis, The Otis Cafe is secretly famous for the quality, quantity and price of its food... it's one of those "Don't tell anyone, but you should know..." sorts of places.) Cascade Head is an Eocene volcanic center, and the basalt- partially submarine, partially subaerial- is interfingered with nearshore marine sediment. And everything is weathered. With the exception of the shore itself, it is no exaggeration to say that the soil and saprolith are 10-15 meters thick.
Except. Except...
In our soil pits, from which we collected samples and water that had leached through the top meter of the soil, we kept finding these clusters of basalt cobbles, about fist-sized. They too were deeply weathered, but under a centimeter or two of clay, quite fresh. Judging by the weathered surface, they were pretty angular; if they had been transported, it wasn't far. Without thinking much about it, I simply assumed they had moved in by soil creep. It turned out later that creep wasn't a tenable mechanism, because there wasn't enough uphill uphill from our site, and no basalt outcrop either.
However, the primary investigator had his own thoughts... he was first and foremost a soil chemist, and these cobble clusters were affecting ground water flow in ways he didn't understand. They also made getting the lysimeters (the devices that captured soil water) into place a real pain, and they were also very sporadic- some pits had none, others had to be abandoned. In short, they were throwing an extra variable into some research that was already more complex than anyone liked, and apparently, he really didn't appreciate this.
So it was with a mixture of excitement and trepidation that I greeted PI's announcement that we were going to figure out once and for all what was going on with the cobble clusters. I didn't have my degree yet, but there was certainly no one else who knew any geology, and I knew immediately that this was show time. It wasn't a situation where my job was on the line- I was a good worker both in the field and lab, and I knew they knew it. But my geologic credibility was on the line, and that was very scary to me.
I had read a master's thesis by Melanie Barnes, (M.S. 1981 The geology of Cascade Head, an Eocene volcanic center in the central Oregon coast range), but I went back through it paying special attention to discussion of the sedimentary facies, which didn't help much. So when the big day came, I still had no real idea what might be going on- though I had dropped the idea of creep. Not only was that physically unlikely for the reasons mentioned earlier, but it didn't sit well with the fact the cobbles came in discrete clusters, not randomly scattered.
So basically, we spent the late morning and much of the afternoon simply driving around, looking for outcrops. Since the bedrock is so deeply weathered, that was more difficult than might be imagined. As Dana learned last week, in the western part of the Pacific Northwest, often the best geology clues and cues can come from subtle color changes in soils and rock weathered in place... but those colors can also be very confusing and misleading. In effect, we spent most of the day carefully examining silty mud. I was at wit's end.
Finally, we came around a corner and there it was:
And even though this is terribly simplified and schematic, and the color differences much more stark than the actual outcrop (also, much less obscured by botany), it really was that clear to me: we were seeing lag cobbles in cut-and-fill structures. In the cartoon above, the dark circles represent the basalt cobbles. Smaller clasts, pebbles, had simply gone completely to clay, and were only noticeable as different colored spots- in others words, not really noticeable at all in the context of our soil pits. In the Eocene estuaries, tidal flats and near shore, drainages from the land, particularly during times of high flow, would incise channels and move the cobbles along as part of their bed load. Later those channels would be filled in as flow decreased or as meandering cut off one location after another. And the clusters of cobbles would be left to confound future scientists.
I've looked around a bit and haven't found any really great photos of cut-and-fill structures, though this one at Andrew Alden's gallery is good, and you can see how the coarser clasts get concentrated at the bottom. Then earlier today, as luck would have it, Suvrat posted a couple of really nice photos- see pictures 3 and 4.
Now why was this so important to me? It required me to figure out something on my own when it counted- this wasn't a class exercise with a right answer, and someone who knew it to check my work afterward. It wasn't just me on my lonesome pondering imponderables. It was work for some people who knew no geology at all, who had no clue what was going on, and to whom the answer really mattered. And I was able to come through and provide an answer, an explanation, that worked with what we knew, and helped explain some of the things we'd seen. Sometimes the cobble clusters seemed to channel groundwater flow. Sometimes they seemed to go back in the soil profile, sometimes they seemed to go across, from the perspective of working in the pits. They seemed to start or end very rapidly on their edges, but at the same time, they had a vaguely linear presentation. The cut and fill model worked with what we knew about the area, and what I knew about geology; it fit, and it explained. It was immensely satisfying.
And though I'll never live to know enough geology to satisfy me, it was the first time that I really understood I knew enough to solve at least some problems that needed solving.
So it was with a feeling of surprise that I knew almost immediately which particular day was the one that stood out in my memory. A bit of background is in order: I referred to myself as the eternal undergraduate. I started at OSU in spring of 1980, and graduated in June of 1988. There were simply no classes left in geology that I was allowed to take, and I had sat in on a number of graduate classes. There were plenty of classes in other departments and disciplines that I'd like to have taken, but it was time to move on. The main thing that enabled this, though, was that 20-30 years ago, it was possible to work one's way through school, pay as you went, and come out debt free. That is not the case any more.
I worked in Clinical Pathology in Veterinary Medicine from the beginning of 1981 until summer of 1983, then I landed a job as a lab and field worker with a forest soils research project, where I ended up working until late 1990- even after I graduated, they found ways to keep me on for a while. One of the projects we worked on for years involved looking at the soils and soil water chemistry at Cascade Head. Below is a map of the area, though it doesn't show old 101, which lies a bit east of the new highway. (Screen capture from page 5 of Research Publications of the Cascade Head Experimental Forest and Scenic Area, 1.4 Mb PDF)
Except. Except...
In our soil pits, from which we collected samples and water that had leached through the top meter of the soil, we kept finding these clusters of basalt cobbles, about fist-sized. They too were deeply weathered, but under a centimeter or two of clay, quite fresh. Judging by the weathered surface, they were pretty angular; if they had been transported, it wasn't far. Without thinking much about it, I simply assumed they had moved in by soil creep. It turned out later that creep wasn't a tenable mechanism, because there wasn't enough uphill uphill from our site, and no basalt outcrop either.
However, the primary investigator had his own thoughts... he was first and foremost a soil chemist, and these cobble clusters were affecting ground water flow in ways he didn't understand. They also made getting the lysimeters (the devices that captured soil water) into place a real pain, and they were also very sporadic- some pits had none, others had to be abandoned. In short, they were throwing an extra variable into some research that was already more complex than anyone liked, and apparently, he really didn't appreciate this.
So it was with a mixture of excitement and trepidation that I greeted PI's announcement that we were going to figure out once and for all what was going on with the cobble clusters. I didn't have my degree yet, but there was certainly no one else who knew any geology, and I knew immediately that this was show time. It wasn't a situation where my job was on the line- I was a good worker both in the field and lab, and I knew they knew it. But my geologic credibility was on the line, and that was very scary to me.
I had read a master's thesis by Melanie Barnes, (M.S. 1981 The geology of Cascade Head, an Eocene volcanic center in the central Oregon coast range), but I went back through it paying special attention to discussion of the sedimentary facies, which didn't help much. So when the big day came, I still had no real idea what might be going on- though I had dropped the idea of creep. Not only was that physically unlikely for the reasons mentioned earlier, but it didn't sit well with the fact the cobbles came in discrete clusters, not randomly scattered.
So basically, we spent the late morning and much of the afternoon simply driving around, looking for outcrops. Since the bedrock is so deeply weathered, that was more difficult than might be imagined. As Dana learned last week, in the western part of the Pacific Northwest, often the best geology clues and cues can come from subtle color changes in soils and rock weathered in place... but those colors can also be very confusing and misleading. In effect, we spent most of the day carefully examining silty mud. I was at wit's end.
Finally, we came around a corner and there it was:
I've looked around a bit and haven't found any really great photos of cut-and-fill structures, though this one at Andrew Alden's gallery is good, and you can see how the coarser clasts get concentrated at the bottom. Then earlier today, as luck would have it, Suvrat posted a couple of really nice photos- see pictures 3 and 4.
Now why was this so important to me? It required me to figure out something on my own when it counted- this wasn't a class exercise with a right answer, and someone who knew it to check my work afterward. It wasn't just me on my lonesome pondering imponderables. It was work for some people who knew no geology at all, who had no clue what was going on, and to whom the answer really mattered. And I was able to come through and provide an answer, an explanation, that worked with what we knew, and helped explain some of the things we'd seen. Sometimes the cobble clusters seemed to channel groundwater flow. Sometimes they seemed to go back in the soil profile, sometimes they seemed to go across, from the perspective of working in the pits. They seemed to start or end very rapidly on their edges, but at the same time, they had a vaguely linear presentation. The cut and fill model worked with what we knew about the area, and what I knew about geology; it fit, and it explained. It was immensely satisfying.
And though I'll never live to know enough geology to satisfy me, it was the first time that I really understood I knew enough to solve at least some problems that needed solving.
Monday, September 27, 2010
A Worldview That Resonates With Me
From The Guardian, a fascinating profile of a member of an indigenous tribe who, quite literally, are making a movie in an attempt to save the world: Save the planet – a message from another world
Aluminum & linoleum table= bauxite, petroleum + LOTS of energy
Concrete floor= shale, limestone, gravel + LOTS of energy
Paint and Varnish= petroleum products, titanium oxide, pigments
Drywall= paper (=fertilizer- ammonium, potash, phosphorus & insecticides-petroleum + salts) and gypsum
Window Glass= quartz sand + sodium, potassium, calcium oxides +/- boron minerals (not so likely for windows)
Cotton Fabric= fertilizer- ammonium, potash, phosphorus & insecticides-petroleum + salts
Copper wiring, Compact fluorescent lights, fan, clock- copper, iron, mercury, glass, plastic (=petroleum)
...and of course, all the transportation infrastructure and fuel/energy costs to get all this stuff from its point of manufacture to this location.
...and of course, I'm JUST focusing on earth materials, because that's what I know.
...and of course, this is just a cursory skim; I could spend the next day or two looking carefully.
That is a deceptively brilliant comment: "The first thing that is noticeable to me is that this is still the world." It is still the world. No matter what we've done to it, no matter how we've processed it to better fit our wants, needs and sensibilities, it's still the world. I do wish there was a greater awareness of that simple fact.
"The first thing that is noticeable to me is that this is still the world," he says. "What's visible is construction, what you have made. This is not something we, the Kogi, are used to seeing. You give precedence to the use of a thing rather than its source. That's the intellectual error. Ultimately, it's all nature." From Jacinto's viewpoint, when we glance at a car we might assess its cost and the status conferred on its driver. We don't recognise it as a clever piece of engineering of resources that once lay inside the earth.This gets at one of the greatest benefits of having some background in geology. I can't look at any man-made creation without also considering the natural resources, particularly those that are geological in nature, that went into making it. I don't think most people ever really stop to look at the stuff around them and wonder where that stuff came from. I've done this activity with students, but I don't think I have on my blog. Looking around the room...
The Kogi are witnessing some of this extraction first hand. Coal mining in the Sierra Nevada has boomed in recent decades (fuelled in part by the demand for cheap foreign coal in post-miners' strike Britain). Over centuries, they survived the wars waged on them by retreating further into the mountains, through dense rainforest and cloud forest dubbed "El Infierno" by settlers. There are still no roads to the Kogi's traditional settlements (Jacinto's home does not exist on official maps), but global capitalism is slowly conquering the Kogi's isolation.
Aluminum & linoleum table= bauxite, petroleum + LOTS of energy
Concrete floor= shale, limestone, gravel + LOTS of energy
Paint and Varnish= petroleum products, titanium oxide, pigments
Drywall= paper (=fertilizer- ammonium, potash, phosphorus & insecticides-petroleum + salts) and gypsum
Window Glass= quartz sand + sodium, potassium, calcium oxides +/- boron minerals (not so likely for windows)
Cotton Fabric= fertilizer- ammonium, potash, phosphorus & insecticides-petroleum + salts
Copper wiring, Compact fluorescent lights, fan, clock- copper, iron, mercury, glass, plastic (=petroleum)
...and of course, all the transportation infrastructure and fuel/energy costs to get all this stuff from its point of manufacture to this location.
...and of course, I'm JUST focusing on earth materials, because that's what I know.
...and of course, this is just a cursory skim; I could spend the next day or two looking carefully.
That is a deceptively brilliant comment: "The first thing that is noticeable to me is that this is still the world." It is still the world. No matter what we've done to it, no matter how we've processed it to better fit our wants, needs and sensibilities, it's still the world. I do wish there was a greater awareness of that simple fact.
Mays Peak Stop 2: Columnar Basalt
Just in time for the latest meme/theme circulating in the geoblogosphere, here is a nice outcrop of columnar basalt. You'll need to click the pics for full size and clarity.
Columnar jointing is actually fairly common in unstressed shallow igneous rocks- by which I mean ones that, as they start to cool, aren't stressed by flow and viscosity or other forces. Thus the feature shows up in mafic and intermediate flows- which are liquid- and in pyroclastic felsic rocks- which are fragmented, but often "sticky" enough to set into a coherent solid. But they most often do not form in felsic flows or domes. As the hot rock cools, it contracts and pulls away from itself. Fractures work in from the surfaces of cooling toward the later-cooling middle of the mass, so the joints are perpendicular to the surface of cooling.
One of the things I like about this outcrop is the way the columns seem to roll over, so you can see them in their traditional columnar form, and from the basal view- along axis- as well. I have to admit, I haven't looked in detail at the contact under this outcrop, but the underlying material looks much more weathered, and may have a channel cut into it.
Here's the Flash Earth location and image... there's a nice paved pullout on the downhill side of the road for this one. I'm not sure if the pullout is there for the obvious geology or for the view, but the view has been overgrown by all the green biological stuff over the years.
As I mentioned at the beginning, over the last day, a whole slew of geobloggers have been posting pictures of columns, and I'm tickled this came up in such convenient proximity to the theme. Others include:
Geotripper, here, here and here,
Sam at Geology Blues
Phillip, also at Geology Blues
Silver Fox, and another columnar post here.
Glacial Till
Life in Plane Light: Squashed columns!
Aaron at Got The Time
These are just the recent ones; if more come up in the near future, I'll try to keep this updated for a few days. For example, I'm sure Dana got more photos... I didn't even get out of the car. And for more background on the interpretation of the Siletz River Volcanics, see my post on our first Marys Peak Stop. Dana has also posted some very nice photos from that stop.
Falling Into Line
Anyway, they'll quiet down in two or three weeks when they start attending their classes.
Sunday, September 26, 2010
Sunday Funnies
If someone ever asks you to describe the Internet to them in four words look them straight in the eye and say “Cats morphing into croissants. The Internet is cats morphing into croissants.” The Daily What
see more Lol Celebs and rebuttal, from the same page:
see more dog and puppy pictures Warp Speed!
I Has a Hotdog
This is a seriously weird world; I'm assuming this is faked, but someone thought to fake it. And I thought it was funny. And Sofa Pizza sez, "I’m having a hard enough time trying to get my 3yr old to use the potty without gliding a vuvuzela up his bunghole."
see more Very Demotivational... this picture has been around for a week or two, but I really like the caption.
