Hill Country Geology, Part Three

We piled back into the min-vans, and headed east down the South Fulton Parkway, toward Cochran Mill Rd. The drive lasted only a couple of miles, but it was time enough to recover somewhat from the harsh wind and cold of the rather wintery late Saturday morning. By the time we parked the vehicles and crossed the road, the sky had clouded up, and a few flurries were falling, and it felt colder than ever. We paused in front of the outrcop again, to try to make sense of it all, in word or gesture (above).

Julie quickly discovered another possible Contact, and this one was much more intriguing. Below was the old standby, Palmetto Granite, with its phenocrysts (large crystals) of feldspar. Above, a series of layers, black and white and intermixed -- a melange of metamorphic material. It was beautiful, and fascinating. It was a Contact where much had happened. The surrounding rock had already been metamorphosed from gosh-knows-what parent rock (shall we take it for granite?), into a well-foliated (layered with minerals) gneiss. Then the granite intruded the gneiss, most likely during the uplift of the Appalachian Mountains, roughly 350 million years ago. The process was an example of regional metamorphism, because it involved the deformation and transformation of rock over a large area, as the result of tectonic forces. The hot magma "baked" the zone where it met the gneiss, causing contact metamorphism, a kind that is localized and usually the result of a magma coming into contact with much colder rock. It was a sort of geological epiphany, to see a metamorphic rock that had, in turn, been metamorphosed again, but in a very different way.

I felt like a college student, back on an introductory geology field trip, getting my eyes opened and seeing rock units in more profound ways than before. It was the kind of experience that is all too rare in book reading (for all the books that I polish off every year) -- a deep knowing that comes from direct encounter, from the experience of witnessing the outcrop and feeling amazement at the story it is telling. This is why geology needs to be taught as a field science, not something that can be learned through "virtual field trips" and computer simulations. What is actually going on out there is much more powerful than what one simply reads about. Maybe T.S. Eliot was right: "Human kind cannot bear very much reality." That discovery, that metamorphosed rock could also be metamorphosed through contact with granitic magma, lingered with me throughout the remainder of the trip, and stays with me now as I type these words. I still recall fondly that moment of enchantment and bliss, there in the bitter wind on that second outcrop of the day, gazing at the Contact and into its secrets.

Hill Country Geology, Part Two

It was the first outcrop of the day, and we piled out of the mini-vans and into a brutal north wind that reminded me of Upstate New York or maybe somewhere along the coast of Baffin Island in the high Arctic. The snow had stopped, at least for the moment. Julie had awoken that morning (Saturday, March 8th) to a half inch of snow blanketing the ground in Carrollton, and had sent me an email even, wondering if we should consider cancelling, on account of the weather. But no, we were all hardy folk, and why would we let freezing temperatures and gusts to thirty miles an hour or more slow us down? So we bundled up, and hit the outcrop: a fairly recent roadcut (one of few left that has not been "tragically" revegetated) along the South Fulton Parkway.

I jumped across the obligatory Swampy Area at the base of the outcrop, through the entirely expected Zone of Briars and Generally Nasty Vegetation, up to the rock face. Granite, mostly -- the good old Palmetto Granite, the stuff of which large boulders are made (such as the ones beside the entrance road into Cochran Mill Nature Center, and in the entrance road, too -- the driveway splits into two one-way routes at a couple of large, well-exfoliated (rounded) chunks of granite). But wait: what was metamorphic rock -- gneiss, probably -- doing here at the granite outcrop? Was it a "Contact"?

I need to pause here and explain for non-geologist readers the sacred nature of the Geologic Contact. In simplest terms, it is the point where two lithological units (rocks of different age or origin) come together. But at those boundaries, amazing things can happen -- stories can be read by a geologist's trained eye, whether of extinctions (the most famous Contact of all, the K-T boundary, marks where the dinosaurs died off) or perhaps an episode of contact metamorphism (a molten granite intruding and baking the surrounding rock) or perhaps even a basaltic flow erupting from a fissure and flowing over the landscape. Bodies of granite are interesting, certainly -- one can describe their textures: aphanitic (fine crystals), phaneritic (large crystals) or porphyritic (a mixture of the two, with some very large crystals). One can further classify them in terms of their mineralogy: is that black speck hornblende, or biotite? One can look for xenoliths, bits of country rock encorporated into the slowly flowing melt (with a viscosity like that of silly putty). But basically, granite is fairly homogeneous stuff, and it gets boring. One starts looking instead for intriguing things growing on the granite, such as lichens and mosses, and even, if desperate, one tries to discern the words in a bit of grafitti covering part of the rock surface. The same is true, for the most part, for metamorphic rocks -- though they occasionally deform into fascinating folds, and some gneisses and schists contain impressive garnets. But the true quarry, the field geologist's quest, is the point of meeting, the Contact.

In the case of this first outcrop of the day, the drama was short-lived. Yes, there was a location on the rock face where granite gave way, rather unspectacularly, to gneiss. But the gneiss was not true country rock, but only an enormous xenolith, perhaps the size of a VW microbus, surrounded by the granite. Matching the spot Julie first found, a distance over on the rock face, a participant discovered another point of meeting, evidence that the rock was just a xenolith, and that the Contact lay elsewhere.

Hill Country Geology, Part One

This past Thursday, March 6th, Dr. Julie Bartley, professor of Geology at the University of West Georgia, spoke at Rico Community Center on the geologic history of the Georgia, particularly our section of the Piedmont. The presentation, which drew a dozen attendees, marked the third month of the first year of our program (yes, already plans are afoot for 2009!), and the last month that our Thursday evening presentations will be held at in Rico. Next month, we will be "on the road" at StudioSwan, a lovely art studio nestled in Serenbe Community (http://www.serenbecommunity.org/). After that, evening talks will be held in the elegant, wood-floored room known as The Studio, also in Serenbe. The Studio offers forty comfortable chairs, bright white walls for PowerPoint projection, and the convenience of being closer to the homes of many of our participants.

Even while I am very excited about upcoming move to The Studio (definitely a step up in refinement and comfort), I will still miss Rico Community Center. There is something about the old elementary school, with its history (recent and not-so-recent) evident in piles of things scattered about (artwork, books, etc.), its donated furnishings, and its quirks, that make it a humble and inviting place to be. For this particular presentation, the site was excellent; Julie placed abundant rock specimens on each table, for participants to classify. It was like being back in school again, a feeling made more tangible by literally being back in school again.

In her carefully prepared talk (broken into sections by time participants spent examining the rock samples), Julie explained to us how the Piedmont is the most complex part of Georgia to interpret geologically. Here, we are in the middle of the Piedmont, far removed from the generally level, younger sediments of the Coastal Plain. Instead, underlying the Hill Country are metamorphic rocks, some deformed several times during various plate tectonic events, intruded by igneous rocks, some of which have themselves been deformed, perhaps even shortly after being emplaced. The result is, well, a mess. And it is a mess that very few people seem to want to tackle. Even Julie prefers to study, in her own fieldwork, Precambrian carbonate reef structures (in such places as Morocco and Siberia). Julie explained that much remains uncertain about Piedmont geology; a new digital geologic map of the Atlanta metro region was recently released, but doubts have already been raised about its accuracy.

The geological story of the region is a story of many tectonic events, including a first collision of land masses, the subsequent opening and then closing of the Iapetus (father of Atlantis) Ocean, convergence of continents to form Pangaea, and the opening of the Atlantic Ocean. Pieces of other land masses, and of island arcs that were once far at sea, now comprise the Eastern seaboard of North America. Our local landscape contains, in the foliation of its gneisses, the tracings of global forces, the pressures that produced mountains. And the story is not a shallow one, either. Exposed now at the surface, the result of millions of years of weathering, are granites and gneisses that were once miles underground. In some places around Atlanta, like at Stone Mountain, the granite that intruded the country rock is a lot more resistant to weathering than the adjacent rock. Given time, the result is a mountain of granite, left behind while the adjacent rock was ground away and carried to sea. In the Hill Country, that granite often outcrops as stretches of rock pavement, more resistant to weathering than the adjacent metamorphic units, but not with a difference in weathering great enough to make our own Stone Mountain here.

We all had a lot of fun, though, just appreciating the complexity of the story, and not worrying too much about the details. Our challenges were, first, to identify which rocks belonged to which of the three major physiographic regions of Georgia: Coastal Plain, Piedmont & Valley and Ridge, and the Blue Ridge. Later in the evening, we worked on a number of black and white rocks, some foliated (schists and gneisses), others not (granites). Wordplay possibilities abounded throughout the evening; at several points, I was sorely tempted to make a remark about not taking everything for granite -- a pun that is rather cliche, I suppose, but is nonetheless tempting to share with novice geologists.

Civil War in the Hill Country, Part Four

In the midst of the Civil War, three generations of the Johnson family came together for a family photograph, outside Richmond, Virginia. The front was moving closer; shortly after the picture was taken, elders, women, and children of the family fled south, back to Georgia. Tom Johnson, the man standing toward the right side of the group, with a beard and hat and holding his wife's hand, stayed behind, to defend the city. He fell in battle a scant few days after the picture was taken, and his body made the journey south, by train. Stories are told of how Tom's wife (and mother of two young children) was returning home on that same train, in another car, and never knew. Only when she returned home did she receive the news. She, and her husband, are both buried in a small family cemetery beside the railroad tracks, a few miles south of Palmetto. Tom's brother, the seated gentleman on the far right in the picture, died before the war was over, in the only major battle fought in Florida, at Olustee. He, too, is buried in this small unkempt graveyard, where several stones are weathered almost smooth, and other graves are marked only by lumps of granite barely protruding from under the cover of oak leaves.

We took our time on this, our last Palmetto Civil War history stop in the middle of a Saturday afternoon. Wandering among the stones, we glimpsed other stories. The graveyard also holds the remains of Hannah Penn, who died in the late 1700s. She was a descendant of William Penn, founder of Pennsylvania; a branch of the family came south, to the Palmetto-Newnan area, eventually marrying into the Johnson family. A displaced Pennsylvanian myself, I paused togratefully recognize the others before me who have uprooted themselves from the Keystone State, to make a new home in the wilds of Georgia.

Civil War in the Hill Country, Part Three

Last Saturday afternoon, after a brief return to Rico Community Center following our morning at Pickett's Mill Battlefield, we visited Civil War sites closer to home. The photo above is, well, basically the heart of downtown Palmetto, Georgia. This was our second stop of the afternoon -- to be nonlinear for a change, I will give it top billing, which probably has not happened before, beyond a couple of local newspaper articles on the occasion of monument dedications, maybe. It is an odd bit of ground for a memorial, situated on a patch of grass next to the unoccupied former train station and the still-busy railroad tracks, bounded on the opposite side by Main Street. The markers here are varied and eclectic. A Daughters of the Confederacy white obelisk from the early 1900s commemorates local units in the "War Between the States"; a roadside sign (shown above) recognizes the Confederate Army of Tennessee, stationed here for a few days shortly after the fall of Atlanta in 1864; a random cannon of no clear vintage (but certainly newer than the Civil War) sits beyond the sign, aimed not-so-menacingly at cars stopped at the traffic light; beyond the cannon is the relocated grave of William Menafee, the man who provided the land where the town now stands (or rather, slumps). I find it fitting, somehow, that the one who gave land to the town got a small plot back, for his own personal and rather long-term use.

The above photograph is of the law office of Jim Barfield in Palmetto, formerly the Stagecoach Inn, circa 1831. Jim proudly notes on his website (http://www.jimbarfield.com/, the source of the lovely out-of-season photograph above) that his office is the oldest commercial building in the whole of Fulton County, though he has only owned it himself for a scant fifteen years. Jim very kindly invited me to allow our Sense of Place Workshop group to tour his office, for which I am very grateful. Our afternoon outing began with a stop here. We admired his fine antiques inside, including a beautiful piece of Creek pottery, shown below. For all that Menafee might have given up his land for the town, it was the Creek's land for far longer than it was his, until McIntosh signed a piece of paper selling the land to the United States -- the Treaty of Indian Springs.But all that was last month -- ancient history. This month is all about how Palmetto became contested terrain a second time, as the Union and Confederacy vied for victory. No major battles were fought here, but the former train station (the one before the one standing there now) was burned by McCook's Federal cavalry, who also tore up and burned the railroad tracks over a two-mile stretch in Palmetto in late June of 1864. Of course, the story of the sacking of the town and destruction of its rail line, connecting Atlanta with Columbus, is a tale told in the absence of evidence, since everywhere was "a scene of fire, of ruin, and devastation" (as quoted in Sherman's Horsemen by David Evans (Bloomington: Indiana University Press, p. 227). So Keith pointed to the current railroad underpasses (the arches with crumbling white plaster) and remarked that the raiders had burned the previous wooden trestles that once stood there, along with the town's original buildings (now gone) and the original rail line (since replaced). All that remains is an anachronistic cannon, like some sort of lawn ornament, a roadside plaque, and local stories.

Back to Jim Barfield's law office. Lots of antiques, but nothing original to the mid-nineteenth century, besides the building itself, with its pine floors with incredibly wide floorboards, the kind that are very hard to come-by nowadays. Upstairs, most of the walls in the two rooms were never painted, and I have read that former occupants of the original tavern left their names on the wood, though I have never seen any. Downstairs, a swinging half-door with chipped gray paint once led to the Confederate post-office, operated out of the building during the war. Mostly what remains are stories. Supposedly, a very important meeting took place in the building, between General Hood and his staff and President Jefferson Davis, who also visited the town after the Battle of Atlanta. In that fateful meeting, which could well have happened there (it was, after all, one of the few available spaces when McCook got through with Palmetto's downtown) or could have happened in a military tent, or possibly elsewhere -- it was at that meeting that General Hood proposed to move north, to cut off Sherman's own rail lines supplying Atlanta. Jefferson Davis, gaunt and weary, approved. A grim miscalucation, to which Sherman responded by burning Atlanta and marching southeast, to the sea.

Leaving Jim Barfield's office, we paused along the brick walkway to notice the sunken stones that were once used by visitors to the stagecoach stop to mount and dismount from their coaches. Slowly, the stones are slipping away, subsiding into the ground. They are apt metaphors for Palmetto history -- so much is hidden, kept in attics or elder residents' memories, and slipping away. Or it is overlooked, intentionally forgotten, like accounts of horrible lynchings that occurred in Palmetto at the turn of the last century, decades after the war had ended -- but that, too, is another story, one difficult to tell.

Civil War in the Hill Country, Part Two

The sky was Confederate gray when we set out on the drive to Pickett's Mill State Historic Site, located on the road to Etowah, near Dallas, Georgia. Eleven of us carpooled from Rico Community Center to the battlefield, where we met up with Dr. Keith Bohannon. I had known that the site had been, until the 1970s, privately owned woods and fields (in fact, it was heavily logged in the 1960s). But I was unprepared for the discovery that not only are there no military monuments there, but there also aren't any roads. The closest to a road was an old track, right beside where we stood, above. That track had been there when the battle was fought, back on May 27th of 1864. In the photo above, the Ravine Overlook is a vantage point for viewing where most of the carnage occurred: the Federal troops occupied the ravine, while the Confederate forces fired down on them with rifles and cannon from this very place. The Confederates held the high ground, and won the battle, though the victory was short-lived; Atlanta fell a few months later.
Our path led along the old roadway, past red flags standing in patches like strange out-of-season flowers. We passed a couple of college students, surveying. Archaeology is ongoing there, particularly near where Pickett's Mill once stood. Archaeologists are hoping to locate the home of the farm family that owned the land, and operated the mill, back in 1864. Their fate is unknown, though it is assumed that they abandoned the area before the battle began. The mill itself was burned down after the battle. All that remains is the well, boarded over and fenced off, and a pair of large square stones on opposite banks of Pumpkinvine Creek. The stones were part of either the mill or, more likely, the mill dam. Such a tranquil place now, but it must have been horrible to be standing there during the battle, when Confederate forces held the high ground on the far side of the creek, pummelling the Federals below with cannon and rifle fire. I cannot imagine the horrors of that battle, or the Civil War in general. The only writer I have found that evokes what I suspect the experience was like is Ambrose Bierce, in short stories such as "Chickamauga". Bierce was present in this battle, too, and he wrote a short essay about the experience, though it did not inspire him to craft a story, the way the Battle of Chickamauga did.

The stream was so peaceful, flowing over boulders of gneiss, the weathered skin of Georgia's upper Piedmont. We admired the way the water splashed over pebbles, flowing through the valley where so much blood must have flowed from fallen soldiers. Later, Keith would explain to us how often it was not possible to tell whether a dead soldier belonged to the Union or the Confederacy; in death, all were brothers.

Our path continued along the stream a short distance, then up the ravine, following the route that Hazen's Brigade of Federal infantry had taken, all the while being fired at from the top of the ravine by dismounted Confederate cavalry. We walked along the edge of a field, which had been planted in wheat at the time of the battle. A terrible place to get caught in crossfire -- sometimes it is not so wonderful to be out standing in one's field.

Continuing upslope, we came to a place where a pair of low ridges with a narrow gully between could be seen under a blanket of oak leaves. Amazingly enough, these earthworks were dug hastily by the federal troops positioned there when the battle began. Over 140 years ago now, yet the land remembers. Could there be a finer monument to the fallen dead than these gentle furrows in the ground?

We made our way back to the visitor center, watching the ravine beside us get deeper and deeper, more and more narrow and rugged. Our band of eleven found the way tough going, and we were not lugging guns and packs. One of us found the uphill route too difficult, and the park service dispatched a small vehicle to pick her up and bring her back. Such a sorrowful place, haunted, in my imagining, by the bodies of so many hundreds dead. I was ready to go home.

Civil War in the Hill Country, Part One

Last Thursday, February 7th, Dr. Keith Bohannon, Professor of History at the University of West Georgia, gave participants an overview of the Civil War history of the region, including the events leading up to and following shortly after Sherman's Atlanta campaign. Amazing, to think that Confederate President Jefferson Davis actually visited Palmetto to speak to the troops! Even more astounding, to think that one of the major events toward the end of the Civil War, a meeting between General Hood, his staff, and Jefferson Davis, may have taken place in a building that we will tour during our outing this coming Saturday! It was that meeting that led to the fateful strategic decision on the part of the Confederacy that ultimately led to Sherman's March. (Or, in this case, Sherman's February?)