Monday, December 24, 2012

A Story of the Season

It’s a moving Christmas story (of sorts) that Giles Miller, Curator of Micropalaeontology at the Natural History Museum, London, tells on his blog.  The occasion for the telling of this tale is the 100th anniversary of a wonderful microscope slide presented by Arthur Earland to Edward Heron-Allen for Christmas in 1912.  A real treat in this fascinating post are the photographs of some of Earland’s slides (Christmas or otherwise).  Reportedly, there was once a slide on which Earland mounted 1,500 foraminifera shells!  (I’ve written previously on my blog about Earland’s Christmas slides on which he painstakingly affixed foraminifera shells in elaborate designs, replete with the year, the season, and his initials.)

Miller recounts how the two men, amateur micropaleontologists working out of the British Museum, had a long collaboration which produced many seminal works on foraminifera, a collaboration which lasted until they had a mysterious and irreconcilable falling out in the early 1930s.  Heightening the intrigue of the rupture between the two men is Earland's reference to “that final woman.”  For some reason (perhaps the two men just look the part), I am reminded of Irene Adler, who was to Sherlock Holmes “always the woman.”

Miller’s blog post is very enjoyable reading in this Christmas season.  Happy New Year.

Saturday, December 22, 2012

Volcanic Pipe Dreams ~ Maps With a View

I have a love-hate relationship with geologic maps which are so often both strikingly beautiful and challengingly complex.  I am drawn to them because they are begging to be read, the swatches of color spread across them hint at wonderful geologic stories.  But, at this stage, I can only enjoy the hints, I just don’t have the necessary grasp of the science or the language to do more.

My latest adventure with geologic maps came earlier this month after Washington Post columnist John Kelly wrote about two volcanoes in Virginia that saw action during the Eocene Epoch (Hidden Depths:  The Mystery of Virginia’s Extinct Volcanoes,  December 15, 2012).  Mole Hill, just to the west of Harrisonburg, Virginia, and Trimble Knob, just outside of Monterey, Virginia, are the very eroded remains of extinct volcanoes.  Courtesy of Google Maps, here’s where they are (the blue markers).

And here's what they look like.

Mole Hill

(This image has been released into the public domain by its author, Jstuby and is available on Wikipedia.)

Trimble Knob

(This image is by Raph Levien and reproduced under a Creative Commons Attribution 3.0 License.  It is available on Wikipedia.)

These volcanoes are a geologic surprise and a puzzle.  The surprise is their age.  Before 1969, the accepted wisdom was that these volcanic remains were no different from nearly all of the other igneous rock in the Blue Ridge and Piedmont provinces that go back hundreds of millions of years.  But, beginning in 1969, analyses of the rocks at these sites have produced estimates that place these volcanoes in the Eocene Epoch (about 56 to 34 million years ago), making them collectively “the youngest igneous rocks in the Eastern United States.”  (C. Scott Southworth, et al., Middle Eocene Intrusive Igneous Rocks of the Central Appalachian Valley and Ridge Province – Setting, Chemistry, and Implications for Crustal Structure, U.S. Geological Survey Bulletin 1839, 1993, p. J17)

The puzzle posed by these volcanic remains emerges from, again, their age.  This area during this Eocene time frame had been thought to be quiescent.  But not now, and, so, the debate is on.  What caused this volcanic activity?  Southworth et al. concluded that the action here during the Eocene was geologically very brief (a few million years), limited in scope, and, on occasion, explosive.  They argued that the volcanic activity at this place and at this time might be best explained by a reopening of basement fractures (the basement is the level below which sedimentary rock does not appear) and a global change in plate tectonic movement that occurred around this time.

Kelly’s article features Elizabeth Johnson, a geologist at James Madison University which is located in Harrisonburg, Mole Hill’s backyard.  These and other extinct volcanoes have become teaching tools.  The focus of her research and, by extension, that of her students, is on the material carried or exploded to the surface.  The central question is what does that material reveal about the Earth’s crust and the depth of the mantle here.

After reading Kelly’s piece and some of the available research on these geological phenomena, I went in search of Mole Hill and Trimble Knob.  Well, actually I stayed at my computer and set out to find geologic maps with a view of these two sites.

A friend of mine approaches our book club books by reading the first few pages and then skipping to the end to read the dénouement.  If the conclusion’s of any interest (and not upsetting), she’ll go back and read the entire book.  Though that’s not how I deal with books, there’s a certain logic for a neophyte coming to geologic maps to be forearmed with a sense of what the maps are intended to tell.  At least, I have a fighting chance of interpreting the language of the maps.

What follows makes it all seem so much more straightforward than it really was.  I’ll even skip going off on how much remains to be done to bring order to the world of maps from state geological surveys and the U.S. Geological Survey, partly because there does seem to have been some progress.  A case in point is the National Geologic Map Database being assembled by the USGS.  Sadly, though, Virginia is the only state on the East Coast included in the very useful MapView product in the Database.  And I have already vented on this topic in an earlier blog post.

Here is a segment of a statewide geologic map prepared by the Virginia Division of Mineral Resources in 1993 (digitized in 2003).

The arrows point to the towns of Monterey (to the west) and Harrisonburg (to the east), not to the volcanic remains which really don’t appear in this map given its small scale – 1:500,000.  At this scale, 1 inch on the map equals 500,000 inches or approximately 7.89 miles, which makes it useful for a broad picture, but not for exploring the geology of these two volcanic sites.  [Note:  I corrected my description of this scale in response to the gracious comment from Silver Fox.  See below.]

Maps with a scale of 1:24,000 give enough detail to focus on Mole Hill and Trimble Knob.  At this scale, 1 map inch equals 2,000 feet or approximately 0.38 miles.  Here is Mole Hill in a 1986 map prepared by the Virginia Division of Mineral Resources (T.M. Gathright, II, and P.S. Frischmann, Geology of the Harrisonburg and Bridgewater Quadrangles, Publication 60, 1986).

The “Tv” symbol in Mole Hill’s orange blob indicates that this is considered a “volcanic pipe.”  As I understand it, the pipe is the passageway through which the magma travels upward.  Upon the death of the volcano, the solidified magma in the pipe proves more resistant to erosion and so is often the last vestige of the volcano.  (Reed Wicander, et al., Essentials of Geology, 2006, p. 90.)  I suspect it's important that Mole Hill is bracketed by faults.  The dotted lines that originate from a point just to the southwest of the hill are used to represent fault lines that are either covered over or inferred by the geologist preparing the map.  “U” indicates the “upthrown side” of the fault (rocks here are displaced upwardly), while “D” is the “downthrown side” (downward displacement).  The light pink that surrounds Mole Hill is identified as “Obud” or the upper dolomite unit of the Beekmantown Group.  This is Ordovician limestone.

Had I expected to find something similar in the maps of Trimble Knob, I would have been disappointed.  As it was, I wasn’t burdened with any expectation, because I invested too much energy struggling to find the appropriate map.  That turned out to be Geologic Map of the Monterey Quadrangle, Virginia (Gerald P. Wilkes, Virginia Division of Geology and Mineral Resources, Publication 178, 2011, scale 1:24,000).

 Hmmm, no indication of a volcanic pipe in this map.  Instead, the pinkish tan blob labeled Trimble Knob carries the letter “b” for “breccia.”  Breccia consists of unworn, coarse rock fragments, often cemented together by a clay matrix.  The map’s author describes the breccia material here as “volcanic, dark-gray to black” with “poorly sorted xenoliths of sedimentary and igneous rock . . . .”  Xenoliths include material from the so-called “country rock,” that is, the layer of original rock through which the volcanic magma penetrated.  In many ways, these are messengers from deep underground.  They are what geologist Elizabeth Johnson analyzes in her effort to comprehend the mantle and crust beneath the Shenandoah Valley.  The pale blue that washes around Trimble Knob represents rock from the Devonian Millboro Shale and Needmore Formation.

I actually don’t think it’s significant that the geologic map depicting Mole Hill appears to differ so much from that for Trimble Knob.  Perhaps it’s just a function of a quarter century (1986 to 2011) of evolving standards and practices in making geologic maps, or different views of different geologist authors.  Geologists Jonathan L. Tso and John D. Surber describe these igneous features in this part of the Shenandoah as “the old plumbing system that once fed a volcanic complex that has since been eroded away.  The larger bodies such as Trimble Knob and Ugly Mountain [West Virginia], may represent old volcanic necks or pipes.”  (Eocene Igneous Rocks Near Monterey, Virginia:  A Field Study, Virginia Minerals, August/November 2006, p. 9).  

The images that open this post and the geologic maps that close it, attest to the fact that we are witnessing the final episode in the life of two volcanoes.  Of course, we won't be here when the last chapter ends.  I think it's fitting to finish with an observation from geologist and paleontologist Ellis W. Shuler (1881 - 1954) about the life spans of volcanoes.  Shuler grew up in rural Virginia during the late 19th century, and, as I described in an earlier post, he opens his book Rocks and Rivers by recounting his first encounter with geology and paleontology.  As a boy of 14, just after reading The Last Days of Pompeii, several earthquakes hit the area around his town of Pearisburg, Virginia (165 miles southwest of Harrisonburg).  Shuler was convinced that Angel's Rest, a mountain that overlooked the town, was about to blow.  The geologist sent from the USGS to explore the causes of this seismic activity befriended the boy and sparked a lifelong interest in geology and paleontology.  There's a poetic touch to Shuler's observation about the ultimate demise of a volcano:
In the end extinction comes to all volcanoes.  Pressures which force up the lavas are relieved and the explosive gases escape.  The volcanic rocks decay to rich soils, and these soils in turn are eroded away.  Volcanic necks, the hard inner core or pipe, survive longest, but these too finally disappear; and the plains of erosion sweep across the site.  The volcanic episode is closed.  (Rocks and Rivers, 1945, p. 170)

Saturday, December 8, 2012

Scientific Poetry

The scientific literature I’ve read recently on my microorganisms of choice – ostracodes and foraminifera – surprised me.  In two of these texts, I found, of all things, poetry.  Prompted by these stray bits of verse, I’ve been considering the nexus of science and poetry.  The idiosyncrasies and limits of my initial exploration are, for better or worse, reflected in this post.

(Ostracodes are tiny crustaceans and foraminifera are single-celled protists.  The shelly fossilized remains of each have figured in several previous posts.)

Crystallographer Alan L. Mackay has asserted that scientific poetry comes in two categories, the first fairly abounding with poems, the second sparsely populated.  (Rhyme and Reason, The Sciences, July/August, 1981.)

The more common is the infusion of scientific terms and concepts into poetry to explore some universal truth.

Among the many examples one could read, let me offer one I particularly like.  Roald Hoffmann’s self-referential poem titled Evolution portrays the poet in the act of writing a poem about how insects are “good chemists,” using chemistry for defense, and, even more so, for attracting mates.

And I was in the middle
of telling the story of the western pine beetle,
which has an aggregation pheromone
calling all comers (of that species).
The pheromone has three components:
one from the male, frontalin,
exo-brevicomin wafted by the female
and (ingenious) abundant
pitch-smelling myrcene
from the host pine.

These lines, in language somewhat reminiscent of a scientific article, albeit with a touch of poetry, describe the complex, precise chemical formula that has evolved for the purpose of propagating the pine beetle.  But the poet and, indeed, the poem he originally drafted are undone, in part, by wild flowers he’d brought into the house and placed in a vase next to the poem.  This flora distracts him from the poem and he observes - 

The sun’s warmth had burst some of the pods,
which had fallen on the draft
(the words were lost in the sun) . . . .

The shadows from the wild flower bouquet lie across his draft deflecting him still further from his original poem, and . . .

Then I saw you walking on the hill.

The poem we have in hand (as I read it) tells us that, whatever wildly wonderful brew of forces that have evolved to attract members of our species to one another, it cannot be deconstructed into an intricate chemical formula, because it’s a quixotic blend of happenstance, the moment, idle musing, light and shadow.

Oh, I should add that Hoffmann is a Nobel Laureate in Chemistry (1981).  The science is as real as the poetry.

(The autobiography Hoffmann submitted to the Nobel Foundation is fascinating; the addendum from 1992 includes some reflection on the relationship of science and poetry.  Hoffmann has made a generous selection of his poetry available on the web.)

Mackay’s second category of scientific poem is the much less populated one consisting of poems in which science is the subject.

Mackay mostly limits this category to recent scientist who write poetry about science.  That's perhaps the safest route since, for older texts, much depends upon what one considers science.  Nevertheless, I'd argue that poems in this group have a very old and distinguished pedigree.  Renowned information scientist Eugene Garfield, in one of his Current Contents columns (which put me on to Mackay in the first place), observes that, in roughly 60 BCE, the Roman poet Lucretius (ca. 99 BCE – ca. 55 BCE) composed De Rerum Natura or On the Nature of Things, “the most extensive description of nature of its time.”  This was the "science of his day."

The poem deals with human nature and religion, but in large part it is a commentary on atomic theory, meteorology, astronomy, the origin of life, and the mechanics of perception.  (The Poetry-Science Connection, July 18, 1983.)

Even the limited amount of this epic poem that I’ve read shows me quite clearly how consonant much of it is with what is known now about the physical world, about the composition of natural objects and the conserving cycles that dominate nature.  A minor example will suffice.  A passage that waxes lyrical about new birth concludes with an observation about fertile death.

Hence the young scamper on their weakling joints
Along the tender herbs, fresh hearts afrisk
With warm new milk.  Thus naught of what so seems
Perishes utterly, since Nature ever
Upbuilds one thing from other, suffering naught
To come to birth but through some other’s death.
(Book I, Substance is Eternal, in the 1916 translation by William Ellery Leonard.)

But I’m reluctant to call it prescient because I don’t know what Lucretius really meant by the terms he used (well, those that I've read in translation).

Still, I agree with Garfield and think Lucretius counts.  Among the other notable scientific poems of past ages that I’d include in this group, is The Temple of Nature; The Origin of Society by Erasmus Darwin (1731 – 1802), a long poem (published posthumously) expounding this Darwin’s views on evolution.

I’ve recently come across a poem that might constitute a third category of scientific poetry – in this category, the poem isn’t ABOUT science, it appears that it IS science.  Or, put another way, the scientist appears to have written the poetry as an integral part of doing science.

Humphry Davy (1778-1829) is a central figure in biographer Richard Holmes’ award-winning book titled The Age of Wonder:  How the Romantic Generation Discovered the Beauty and Terror of Science (2008).  Davy made significant contributions to chemistry in this fecund period for the arts and sciences.  During the Romantic Age, the arts, particularly poetry, and science seemed twinned, practitioners of each were often one and the same, or, at least, close collaborators.  So, it’s not surprising that the chemist Davy was also a poet.

Very early in his career, Davy experimented with the effects of different gases on the human body and mind.  Indeed, the body and mind on which he experimented were often his own.  When sessions with carbon monoxide proved nearly fatal, he wisely tried a different gas, nitrous oxide, with categorically different and addicting results.  As part of his research, Davy used poetry to capture the essence of a gas high.  In a poem titled On Breathing Nitrous Oxide, he wrote

Yet is my cheek with rosy blushes warm
Yet are my eyes with sparkling lustre filled
Yet is my mouth replete with murmuring sound

Though Holmes dismisses the poem as “very bad verse,” he calls it "a form of scientific data," suggesting to me that it should be considered part of Davy's effort to immediately record what he'd experienced (p. 260).  Holmes posits that it provided “surprisingly precise physiological information” of the gas’ impact from sexual arousal to flushed cheeks, from hallucinations to a sense of physical prowess.

Reflecting the shared worlds of poetry and science in this period, Davy proved an admirable host for nitrous oxide sampling sessions, inviting such friends as the poets Robert Southey and Samuel Taylor Coleridge.  Not unexpectedly, Coleridge, who was deeply into opium, was not as moved as others.  Holmes writes, “In fact Coleridge’s accounts of his reactions to the gas seem oddly prosaic.”  (p. 267)

One might expect that the two poems on ostracodes and foraminifera that I found nestled in scientific articles might fit into this third category, as examples of the scientist doing science through poetry.  But, I think not.

I’m not sure where they belong, perhaps yet another category.  They speak to no truths about the human condition, and their subject is hardly science, though it has the appropriate patina.  Because these are not free-standing poems, their context – scientific journals – is all important and seems to dictate that they be played for . . . laughs.  Indeed, they are trivial.  That said, I did enjoy the poems and their articles, and it’s pretty clear the authors had fun writing them.

The first article, titled The Odds on “Ode” in Ostracode, or the Omicron and Omega of Chancy Spelling, appeared in the Journal of Paleontology (November, 1961) and tackles that most fundamental of issues for those who work with ostracodes –

Should the common name of these little crustaceans be spelled ostracode or ostracod (with appropriately different pronunciations)?

Paleontologist Richard H. Benson argues in this piece, from carefully assembled and footnoted etymological evidence regarding the use of the two terms, that ostracode is much the preferred.  He concludes with his Ode to Ostracode which in doggerel sums up his preceding detailed analysis.  The first two verses capture the essential geopolitical struggle over the spelling of the name.

In celebration of Oxford’s mode,
Most Americans spell it “ostracode.”

The Britisher’s closer proximity to God
Causes him to spell it “ostracod.”

The poem draws other nationalities into the fight, but notes that it’s of little consequence to most of the world.  Benson concludes the poetic effort with

I end this ode with a short delighter;
Both may be right, but one is righter!

The second of these poems appears in What Should We Call The Foraminifera?, a footnoted piece by Jere H. Lipps, Kenneth L. Finger, and Sally E. Walker, that appeared in the October, 2011, issue of the Journal of Foraminiferal Research.  Sally Walker is the designated poet in the group.  Her poem, titled Protist Protest, begins

Little protists of the sea
How do we treat thee?
As foraminifers, Oh wee beasties of the sea?
Or, shall it be, foraminifera
for the plural or the singular?

And ends with - 

Please, please tell me Dr. Foram Man or M’am,
Is it –minifer, -minifera, or –miniferan?

It would have pained me to end this post with such verse, so I wont.

As a lover of the fossil shells left us by gastropods, I am particularly taken with Roald Hoffmann’s poem Malacology, a dialogue about finding the universal in the quotidian, which finishes the whirling pattern it traces down the page with these lines arrayed in this fashion - 

But a snail –
            won’t it matter
                        it’s so glan-
                                    dular, all its
                                                            on display?

                        That’s what I
            said from the
            the world is
                        in a snail.

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