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Stone walls

Walk into a patch of forest in New England, and chances are you will—almost literally—stumble across a stone wall. According to Robert Thorson, a landscape geologist at University of Connecticut, these walls are “damn near everywhere” in the forests of rural New England.

Jeanna Bryner, in Livescience, writes about the rediscovery of the lost archaeological landscape of New England.

Leaf-off (left) and Leaf-on (right) aerial photographs with a modern road superimposed through the northeast corner of the image for reference .

Aerial New England forest optical stone walls

These stone walls and other archaeological features could not be seen with traditional aerial photographs shown here. This figure illustrates the advantage of LiDAR data with a point spacing of 1 meter or better over traditional map views of the landscape for archaeological purposes.

Examinations of airborne scans, using light detection and ranging (LiDAR), of three New England towns have revealed networks of old stone walls, building foundations, old roads, dams and other features, many of which long were forgotten. Here, stone walls are yellow, abandoned roads are red, and building foundations are outlined by green squares.

Aerial New England forest LIDAR stone walls

LiDAR is not only a powerful tool on its own; it can also be used in conjunction with the many types of historical documents available to those performing research in this geographic area,” Johnson and Ouimet write in the Journal of Archaeological Science.

As an example, this 1934 aerial photograph taken of an area in Preston, Conn., shows a farmstead — cleared fields, forest, stone walls or fences, a house, a barn and other outbuildings, and a road running through the farm.

Aerial forest Connecticut stone walls

Now compare with this aerial image from 2012.

Aerial forest Connecticut stone walls 2012

from Livescience, Images: ‘Lost’ New England Archaeology Sites Revealed in LiDAR Photos, 1/16/14

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New England Is Crisscrossed With Thousands of Miles of Stone Walls

That’s enough to circle the globe—four times.

By Anna Kusmer 5/4/18

Walk into a patch of forest in New England, and chances are you will—almost literally—stumble across a stone wall. Thigh-high, perhaps, it is cobbled together with stones of various shapes and sizes, with splotches of lichen and spongy moss instead of mortar. Most of the stones are what are called “two-handers”—light enough to lift, but not with just one hand. The wall winds down a hill and out of sight. According to Robert Thorson, a landscape geologist at University of Connecticut, these walls are “damn near everywhere” in the forests of rural New England.

He estimates that there are more than 100,000 miles of old, disused stone walls out there, or enough to circle the globe four times.

Who would build a stone wall, let alone hundreds of thousands of miles of them, in the middle of the forest? No one. The walls weren’t built in the forest but in and around farms. By the middle of the 19th century, New England was over 70 percent deforested by settlers, a rolling landscape of smallholdings as far as the eye could see. But by the end of the century, industrialization and large-scale farms led to thousands of fields being abandoned, to begin a slow process of reforestation.

“New England had great pastures,” says Thorson. “It was a beef-butter-bacon economy.”

As farmers cleared those New England forests, they found rocks—lots and lots of them. The glaciers that receded at the end of the last Ice Age left behind millions of tons of stone in a range of sizes. New England soils remain notoriously stony today.

When life gives you stones? Build a wall. Farmers pulled these plow-impeding stones from their fields and piled them on the edges. “The farmer’s main interest was his fields,” says Thorson. “The walls are simply a disposal pile. It was routine farm work.” This process was replicated at thousands of farms across the region—a collective act of labor on a glacial scale.

The supply of stone seemed endless. A field would be cleared in the autumn, and there would be a whole new crop of stones in the spring. This is due to a process known as “frost heave.” As deforested soils freeze and thaw, stones shift and migrate to the surface. “People in the Northeast thought that the devil had put them there,” says Susan Allport, author of the book Sermons in Stone: The Stone Walls of New England and New York. “They just kept coming.”

Wall-building peaked in the mid-1800s when, Thorson estimates, there were around 240,000 miles of them in New England. That amounts to roughly 400 million tons of stone, or enough to build the Great Pyramid of Giza—more than 60 times over.

No one dedicates more time to thinking about these walls than Thorson, who has written a children’s book, a field guide, and countless articles about them since he first moved to New England in 1984. Thorson, bald and bearded, a mossy stone himself, is a landscape geologist, and he distinctly remembers his first walks in the New England woods—and coming across one stone wall after another. His mind was full of questions about what they were and who built them, “it was a phenomenon that was extraordinary,” he says. “One thing led to another, and I got obsessed on the topic”.

Thorson started the Stone Wall Initiative in 2002, aimed at educating the public about this distinctive feature of their forests, in addition to conserving the walls and studying how they impact the landscape around them. Thorson has built a reputation as the ultimate expert on this phenomenon. “You know how a natural history museum would have a person who identifies stuff for you? I’m kind of that guy for stone walls,” he says.

Every year he takes his students to a maple-beech forest stand in Storrs, Connecticut, which he calls “The Glen,” to look at a classic farmstead stone wall. This wall is thigh-high, and mostly built of gneiss and schist, metamorphic rocks common in the valley flanks of central New England. With Thorson’s help, one begins to see a little structure in how the stones were stacked—in messy tiers, by a farmer who added one load at a time.

Thorson may be particularly obsessed with the walls, but he’s not alone in the interest. He is constantly invited to speak at garden clubs, historical societies, public libraries, and more. “The interest doesn’t die down,” he says. “Twenty years later, it’s still going on.”

His field guide, Exploring Stone Walls, is a directory of some of the most unusual, interesting, or distinctive walls in the region. The tallest example is a mortared sea wall beneath the Cliff Walk in Newport, Rhode Island, measuring over 100 feet. The oldest wall, in Popham Point, Maine, dates to 1607. Thorson’s favorite historically significant wall is at the Old Manse, a historic home in Concord, Massachusetts. It provided cover for minutemen firing on the British during the Revolutionary War. Thorson also highlights Robert Frost’s “Mending Wall,” located on his farm in Derry, New Hampshire, the inspiration for the famous line, “Good fences make good neighbors.”

Thorson knows about as much as one can know about the world-wonder- scale web of walls across the Northeast, but there remains much to learn, particularly in terms of what they mean for ecosystems, such as their role as both habitat and impediment to wildlife, and their effect on erosion and sedimentation. “It sounds silly,” he says, “but we almost know nothing about them.”

Geographer and landscape archaeologist Katharine Johnson earned her doctorate mapping stone walls from above, using lidar (light detection and ranging) technology. Lidar is similar to radar, only instead of using radio waves to detect objects, it uses light. Laser pulses—thousands per second—are emitted from a specially equipped plane. There are so many of these pulses, that some are able to hit the small spaces between leaves and penetrate all the way to the forest floor, even through thick tree cover. Johnson’s lidar images reveal the exent of those crisscrossing stone walls in a way nothing else can.

Her research shows that, stripped of the region’s resurgent forests, the walls provide a snapshot of 19th-century history—a map of what land was cleared and farmed at the time. Combined with other data on the forests themselves, this can help specialists model historic forest cover and, in turn, help ecologists understand how forests grow back after they have been disturbed or cleared entirely. The walls can hold the key to New England’s social history, including settlement patterns and farming styles. They provide a static backdrop against which change can be measured.

“Stone walls are the most important artifacts in rural New England,” Thorson says. “They’re a visceral connection to the past. They are just as surely a remnant of a former civilization as a ruin in the Amazon rain forest.”

Each of the millions of stones that make up New England stone walls was held by a person, usually a subsistence farmer, or perhaps a hired Native American or a slave. What remains is a trace of countless individual acts etched on the landscape. “Those labors,” says Allport, “hundreds of years later, they endure.”

source atlasobscura.com/articles/new-england-stone-walls

Related references

https://www.livescience.com/42638-lost-new-england-archaeology-lidar-photos.html

https://news.nationalgeographic.com/news/2014/01/140103-new-england-archaeology-lidar-science/

Scientific articles

Rediscovering the lost archaeological landscape of southern New England using airborne light detection and ranging (LiDAR), Katharine M.Johnson and William B.Ouimet, Journal of Archaeological Science, Volume 43, March 2014, Pages 9-20

This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.

§107. Limitations on Exclusive Rights: Fair Use.  Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include: the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes; the nature of the copyrighted work; the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)
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Learning Standards

Massachusetts History and Social Science Curriculum Framework

HISTORY AND GEOGRAPHY
1. Use map and globe skills learned in prekindergarten to grade five to interpret different
kinds of projections, as well as topographic, landform, political, population, and climate
maps. (G)
2. Use geographic terms correctly, such as delta, glacier, location, settlement, region,
natural resource, human resource, mountain, hill, plain, plateau, river, island, isthmus,
peninsula, erosion, climate, drought, monsoon, hurricane, ocean and wind currents,
tropics, rain forest, tundra, desert, continent, region, country, nation, and urbanization.
(G)
3. Interpret geographic information from a graph or chart and construct a graph or chart
that conveys geographic information (e.g., about rainfall, temperature, or population
size data). (G)

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How elections are impacted by a 100 million year old coastline

How elections are impacted by a 100 million year old coastline

Earth Science and Geology impact American social and political life in unexpected ways

Hale County in west central Alabama and Bamberg County in southern South Carolina are 450 miles apart.  Both counties have a population of 16,000 of which around 60% are African American.  The median households and per capita incomes are well below their respective state’s median, in Hale nearly $10,000 less.  Both were named after confederate officers–Stephen Fowler Hale and Francis Marion Bamberg.  And although Hale’s county seat is the self-proclaimed Catfish Capitol, pulling catfish out of the Edisto River in Bamberg County is a favorite past time.

These two counties share another unique feature. Amidst a blanket of Republican red both Hale and Bamberg voted primarily Democratic in the 2000, 2004, and again in the 2008 presidential elections.  Indeed, Hale and Bamberg belong to a belt of counties cutting through the deep south–Mississippi, Alabama, Georgia, South Carolina, and North Carolina–that have voted over 50% Democratic in recent presidential elections.

Why? A 100 million year old coastline.

Creteaceous North America coastline

During the Cretaceous, 139-65 million years ago, shallow seas covered much of the southern United States.   These tropical waters were productive–giving rise to tiny marine plankton with carbonate skeletons which overtime accumulated into massive chalk formations.  The chalk, both alkaline and porous, lead to fertile and well-drained soils in a band, mirroring that ancient coastline and stretching across the now much drier South.   This arc of rich and dark soils in Alabama has long been known as the Black Belt.

But many, including Booker T. Washington, coopted the term to refer to the entire Southern band. Washington wrote in his 1901 autobiography, Up from Slavery, “The term was first used to designate a part of the country which was distinguished by the color of the soil. The part of the country possessing this thick, dark, and naturally rich soil…”

Cretaceous rocks Alabama

Over time this rich soil produced an amazingly productive agricultural region, especially for cotton.  In 1859 alone a harvest of over 4,000 cotton bales was not uncommon within the belt. And yet, just tens of miles north or south this harvest was rare.  Of course this level of cotton production required extensive labor.

Cotton in 1859 USA

As Washington notes further in his autobiography, “The part of the country possessing this thick, dark, and naturally rich soil was, of course, the part of the South where the slaves were most profitable, and consequently they were taken there in the largest numbers. Later and especially since the war, the term seems to be used wholly in a political sense—that is, to designate the counties where the black people outnumber the white.”

Slaves 1860 American south

The legacy of ancient coastlines, chalk, soil, cotton, and slavery can still be seen today.   African Americans make up over 50%, in some cases over 85%, of the population in Black Belt counties.  As expected this has and continues to deeply influence the culture of the Black Belt.  J. Sullivan Gibson writing in 1941 on the geology of the Black Belt noted, “The long-conceded regional identity of the Black Belts roots no more deeply its physical fundament of rolling prairie soil than in its cultural, social, and economic individuality.”  And so this plays out in politics.

Census 2000 black percent African American

This Black Belt with its predominantly African American population consistently votes overwhelmingly for Democratic candidates in presidential elections. The pattern is especially pronounced on maps when a Republican candidate has secured the presidency as Bush did in 2000 and 2004.  In Southern states where a Republican secures the nomination, almost the entirety of Black Belt counties still lean Democratic. This leads to a Blue Belt of Democratic counties across the South. Even when Clinton, a Democrat, overwhelmingly took most Southern states, the percentages of those voting Democrat was still highest in the Black Belt counties.

Election Results 1964

But the Black Belt has not always been visible on maps during elections.  The Voting Rights Act, outlawing discriminatory voting practices, was passed in 1965.  As result, a year earlier in the 1964 elections larger numbers of African Americans were excluded from the polls in Southern states.  And, in turn, the blue band we see today was not visible.

Long heralded as the Black Belt for rich dark soils and later for the rich African American culture and population, it may equally be referred to as the Blue Belt to reflect both its oceanic geology and the political leanings that resulted from it.

About the author: Craig McClain is the Executive Director of the Lousiana University Marine Consortium. He has conducted deep-sea research for 20 years and published over 50 papers in the area. He has participated in and led dozens of oceanographic expeditions taken him to the Antarctic and the most remote regions of the Pacific and Atlantic.

Deep Sea News: How presidential elections are impacted by a 100 million year old coastline

–  – – – – – – – – – – – – – –

Now we move to further data, from the original article,  Geology and Election 2000: Overview, by Steven Dutch, Natural and Applied Sciences,University of Wisconsin – Green Bay

On the map of electoral returns for the presidential election of 2000 is a feature instantly recognizable to a geologist: in the otherwise pro-Bush South, an arcuate band of pro-Gore counties sweeps from eastern Mississippi, across Alabama and Georgia and into the Carolinas.

Election results 2000

My geologist’s eye was immediately drawn to this arc because it coincides almost exactly with a series of rock units on the Geologic Map of the United States. Why would election returns follow rock outcrops?

In the map below, Cretaceous rock units (139-65 million years old) are shown in shades of green. Older rock units are in gray, younger ones in yellow. The complex NE-trending patterns in Alabama, Georgia and South Carolina are deformed rocks of the Appalachians. In NW Alabama, the older rocks are flat-lying layers of the continental interior.

Cretaceous rocks Alabama

Comparison with the geologic maps shows that the arc actually consists of three segments.

  • In Mississippi and Alabama the pro-Gore band of counties corresponds very closely with the units labeled uK – upper Cretaceous. We might suspect that  the most likely explanation for this part of the arc has to do with economic patterns dictated by the soils. Most of the electoral and demographic patterns associated with the band end abruptly in NE Mississippi.
  • In Georgia, the Cretaceous outcrop band is very narrow. It is surprising how clear the pro-Gore band is in Georgia considering how narrow and discontinuous the outcrop band of Cretaceous rocks is. This part of the arc may have less to do with the rocks themselves than the boundary between the Appalachians and the Coastal Plain.
  • In South Carolina, however, the band of Democratic counties is well defined but is consistently seaward of the Cretaceous rock units. In fact, on some maps there seems to be a weak anti-correlation between the Cretaceous rocks in South Carolina and the political and demographic trends noted for the other three states. However, the South Carolina portion of the arc turns out to be consistent in election returns and a variety of other demographic factors.

This band shows up with varying degrees of prominence for previous elections as well. It shows the same correlation with rock units in Mississippi, Alabama and Georgia and the same lack of correlation in South Carolina. It further shows strong correlation with demographic trends.

The Coastal plain rocks slope gently seaward toward the Gulf and Atlantic coasts, a structure called a homocline. I therefore propose to call the arc of pro-Democratic counties, which is reflected in a variety of demographic trends, the Cretaceous Homoclinal Arc of Demography, which can be abbreviated by an acronym that more than anything else symbolizes the election of 2000: CHAD.

(more to come)

text

This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.

§107. Limitations on Exclusive Rights: Fair Use

Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include:

the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
the nature of the copyrighted work;
the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)

It’s Open Season on Interpreting the Geology of Pluto and Charon

At less than a million miles from Pluto leading up to closest approach flyby on Tuesday, the New Horizons probe is sending back outright spectacular images of the dwarf planet and its largest moon. Every batch of best-ever images sparks speculation on what geology underlays the features on these distant, rocky worlds. Geomorphology is the large-scale study of landforms, unravelling the story of how they formed like a murder mystery on geologic timescales of millennia. We’re just starting to get back images from the New Horizons probe that are detailed enough to start guessing at the geomorphology of Pluto and now of its largest moon Charon….

It’s Open Season on Interpreting the Geology of Pluto and Charon