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TRANSCRIPT
Atlanta Geological Society Newsletter
ODDS AND ENDS Dear AGS members,
According to the calendar fall is here, although as I
write this, it still feels very much like summer. But
this is the time of year to plan for a fall field trip.
What I have proposed is to run a fieldtrip in
Lawrenceville that utilizes local outcrops and the
fine work of the USGS when they helped the City of
Lawrenceville develop their water supply. The
planned day is Saturday October 14th and coincides
with the last day of Earth Science Week. The USGS
work involved field mapping, the drilling of about
30 exploratory wells and then aquifer tests to
confirm the production yields. Lester Williams, a
former USGS hydrogeologist has been invited to
provide his personal insights into the development
of the conceptual site model for this area and how it
might be used for water supply exploration in the
Piedmont.
It won’t be just about water supply. For all of us that
work in the Piedmont, you will see how the
fractures and weathered zones provide conduits into
the subsurface. This is important to visualize for
understanding the transport of those pesky
hazardous constituents that many of us deal with in
our work day world. I’ll be sending out more details
by email in the following weeks.
Also, look on Page 14 in the newsletter for the field
trip details of the Georgia Geological Society. Their
trip is scheduled for October 6-8 and will address
the tectonic setting and correlation of Taconic
backarc and arc terrains in the Inner Piedmont and
Talladega belts of west Georgia and Alabama.
Hope to see you Tuesday!
Ben Bentkowski, President
September Meeting
Join us Tuesday, September 26, 2017 at
the Fernbank Museum of Natural History,
760 Clifton Road NE, Atlanta GA. The
meeting/dinner starts at 6:30 pm and the
meeting starts approximately 7 p.m.
This month’s presentation is: “Interactive
GIS-Based Geological Field Guide and
Geodatabase for Georgia” presented by
Dr. Katayoun Mobasher. Please find more
information about Dr. Mobasher bio on
Page 4 of the newsletter.
Please come out, enjoy a bite to eat, the
camaraderie, an interesting presentation and
perhaps some discussion on the importance
of accurate mineral characterization. Also,
the differences that can exist between
mineralogical, industrial and regulatory
definitions for minerals.
Keep up to date with the AGS at:
www.atlantageologicalsociety.org
or at Facebook
facebook.com/Atlanta-Geological-
Society
Page 2 AGS September 2017
This Month’s Atlanta Geological Society Sponsor
AGS September 2017 Page 3
Page 4 AGS September 2017
This Month’s Atlanta Geological Society Speaker Dr. Katayoun Mobasher is a faculty member in the Lewis F. Rogers Institute for Environmental and
Spatial Analysis (IESA). She began her academic career in 2001 as a teaching assistant at Georgia State
University. In 2005 she worked as a lecturer of geology at Berry College in Rome, GA teaching
environmental geology, and introductory geology courses and labs. She then moved to Georgia State
University and worked as a visiting instructor of geology teaching introductory geology courses and
Introductions to Earth’s Materials. Dr. Mobasher came to the Gainesville campus in 2008 as an
assistance professor of geology. She became an associate professor in 2012 at the University of North
Georgia. Dr. Mobasher is a certified GIS Professional (GISP).
Interactive GIS-Based Geological Field Guide and Geodatabase for Georgia
Field experiences are the basis for all geology curriculum, providing students with opportunities to better
understand how the concepts they learn and study in a geology classroom translates to real-world
experiences. Field guides are excellent resources to facilitate the transformation of information from an
expert field geologist to students and other instructors for teaching, learning, and research purposes from
the field.
The Georgia Geologic Field Guide Database is a pilot project for making field guides and other essential
information more accessible and useful to geoscience educators, students, and researchers. In order to do
so, a GIS geology geodatabase of Georgia was developed containing attribute fields designed to store
relevant information of geologic features in each of the physiographic provinces of Georgia. In order to
make the information accessible, the GIS web-based application ArcGIS Online was utilized as well as
its many integrated web applications - Story Journal, Survey123, ArcGIS Collector, and Story Map. The
GIS-based field guide modules allows for field data collection through Survey123 where each member
of the group can contribute their own field information and have it added to the geodatabase. Each
verified geologic location are shown on the GIS-based field guide which has an associated map, photo,
video, geologic sketches and petrographic photos. The application is also supplemented with a web link
to our Gigapan© photography for various locations and has an embedded work book that makes it ideal
for teaching purposes.
AGS September 2017 Page 5
Laser Mapping Project Shows Effects of Physical Changes In
Antarctica's Dry Valleys
Researchers funded by the National Science Foundation (NSF) have publicly released high-resolution maps of
Antarctica's McMurdo Dry Valleys, a globally unique polar desert. The high-resolution maps cover 3,564 square
kilometers of the McMurdo Dry Valleys and allow researchers to compare present-day conditions with lower-
resolution LIDAR surveys conducted almost 13 years ago.
Scientists from Portland State University led the new research project, which mapped the area using more
sophisticated LIDAR, a remote-sensing method that uses laser beam pulses to measure the distance from the
detector to the Earth's surface. Two NSF-funded facilities, the Open Topography Facility and the Polar
Geospatial Center, made the LIDAR data publicly available. A paper about the work was published in the
journal Earth System Science Data. The data, collected by aerial survey missions flown in the Southern
Hemisphere in the summer of 2014-2015, provide detailed topography of the perpetually ice-free region, where
surprising landscape changes, such as rapid erosion along some streams, have been observed in recent years.
The freely available datasets will allow scientists to get a handle on how widespread and how significant
changes to the frozen landscape might be in this ecologically sensitive region.
The National Center for Airborne Laser Mapping and the Portland State University team carried out the mapping
during an eight-week field season, beginning in December 2015. They flew instruments aboard a Twin Otter
aircraft operated by Kenn Borek Air, Ltd., under contract to Unfeatured of the McMurdo Dry Valleys are
interesting to a wide range of scientists, from biologists to geologists to glaciologists. For example, the Dry
Valleys are one of the few places on the massive continent -- the size of the U.S. and Mexico combined -- where
bedrock is exposed, allowing geologists to reconstruct the continent's geological history from samples.
The region is home to one of NSF's Long-Term Ecological Research (LTER) sites, the McMurdo Dry Valleys
LTER. Researchers at the site study the extremely cold and dry habitat, which is dominated by microbial life in
the soil and in unique ecosystems under at least one of its glaciers and in several of its highly salty lakes.
The cold, dark environment of the McMurdo Dry Valleys is the ecosystem on Earth that most closely resembles
the surface of Mars. Evidence of past glacial advance and retreat is also more easily observed in the Dry Valleys,
providing a window into the past behavior of the vast Antarctic ice sheets and their influence on global sea
levels.
Read more a thttp://www.opentopography.org/news/mcmurdo-dry-valleys-antarctica-lidar-now-available
3-D Elevation Maps Of Alaska For Released For White House Arctic
Initiative
The digital elevation models, or DEMs, serve as a benchmark for measuring future climate changes in the Arctic
by assisting scientists studying glaciers, permafrost collapse, and coastal retreat. All of the information is
publicly available online. The DEMs also provide critical new information for ground and air transportation
safety, land management, sustainable development, and scientific research.
"With these digital elevation models we can see detailed topography of the land, including individual trees,
lakes, roads and buildings," said Paul Morin, director of the University of Minnesota's Polar Geospatial Center.
"This high-resolution data is invaluable. For example, researchers and land managers can use the data to
"digitally rain" on a surface and watch where the rain goes to analyze watersheds."
Page 6 AGS September 2017
3-D Elevation Maps Of Alaska For Released For White House Arctic
Initiative (Continued)
The digital elevation models are based on 50-centimeter resolution images captured by Digital Globe
commercial satellites and licensed by the National Geospatial-Intelligence Agency.
"We used sub-meter optical satellites to collect stereo imagery from space. We broke the Arctic up into 20
trillion two-meter-by-two-meter squares and then used one of the most powerful computers to measure the
height of each of those squares," Morin said. "We are measuring the surface of Earth at a resolution and
geographic scale and spatial resolution that no one has ever done before. It is one of the most exciting things I've
ever seen in my career."
This technology is significant in polar mapping because it allows for a wider coverage of the Arctic than did
traditional data collection by aircraft, which is limited in the inhospitable and remote polar region. The data can
also be collected again in the future to watch ice, permafrost and vegetation change over time.
Funded by the National Science Foundation (NSF), researchers at the University of Minnesota, Ohio State
University and Cornell University have been using the National Center for Supercomputing Applications
(NCSA) Blue Waters supercomputer at the University of Illinois at Urbana-Champaign, one of the most
powerful supercomputers in the world. The U.S. Geological Survey and the State of Alaska were also key
partners in coordinating the project internationally.
Teams from NGA and NSF worked with the partners to launch an unclassified, open Arctic portal where the
DEMs and emerging information is available to the public. Esri, a geographic information system provider,
hosts the site at nga.maps.arcgis.com. The public website hosts webmaps, map viewers, other DEM exploratory
tools, nautical charts, sailing directions, and infographics. It also includes a downloadable Pan-Arctic map with
mission-specific data layers.
The United States serves as the chair of the Arctic Council through Spring 2017 when the position rotates to
Finland for two years. The White House Arctic Initiative supports efforts to understand the Arctic, engage with
residents, and develop tools, products and services that improve federal, state and local activities in the Arctic.
Digital elevation models of the entire Arctic are scheduled for release in 2017.
Read more at https://www.sciencedaily.com/releases/2016/09/160901211414.htm
O
The digital elevation models, or DEMs, serve as a benchmark for measuring future climate changes in the Arctic by assisting scientists studying glaciers, permafrost collapse, and coastal retreat. Credit: University of Minnesota Polar Geospatial Center
AGS September 2017 Page 7
After A Dive Into Saturn, Cassini Spacecraft Melts Into History
After 13 years revolutionizing our understanding of the solar system, NASA’s Cassini spacecraft melted this
morning during its final, fatal partial orbit into the upper reaches of Saturn.
For about a minute, running on half a hair dryer’s worth of power, the orbiter-cum-probe beamed direct
measures of the planet’s atmosphere, along with final probes of its gravity and magnetic field, to mission
control at the Jet Propulsion Laboratory (JPL) in Pasadena, California. Then, finally, its thrusters, designed for
the vacuum of space, could no longer counter Saturn’s turbulence to keep its antenna in line with Earth.
“The signal from the spacecraft is gone,” said Earl Maize, Cassini’s project manager. “And in 45 seconds, so
will be the spacecraft.” The spacecraft’s aluminum and carbon mylar then melted into the folds of Saturn’s
elemental abyss. Cassini had delivered 30 more seconds of data than expected. Until their vaporizing end, all
systems were nominal.
The spacecraft’s demise, necessitated by dwindling fuel and a need to protect two of Saturn’s 62 moons from
potential microbial contamination from Earth, has brought forth a global outpouring of sentiment. Images from
its 12 instruments, spread on currents of social media unimaginable when the mission was conceived in the
1980s, decorate dorms and desktops. It had become typical to know, in fine detail, on any given day, the
weather on Saturn. Those days are no more.
On large screens mounted on Beckman Mall at the California Institute of Technology in Pasadena, in a sleepy
predawn haze, the mission’s extended web of researchers watched the signal fade out. Many have known each
other for decades, their families growing up together at science meetings spread across the globe. “My
scientific life is tied to this spacecraft, to this mission,” says Luciano Iess, a planetary scientist at the Sapienza
University of Rome who has led Cassini’s radio experiment since 1990. But though nostalgia and sentiment
ruled those few hours, many are eager to get back to the work at hand. “What I can tell you is many of our
models are too simple or just out and out wrong,” says Linda Spilker, Cassini's project scientist at JPL. There
is much more to do.
Cassini's farewell glance at Saturn's ring, taken 13 September 2017.
Saturn's rings have served as a sort of time machine for Cassini's
scientists, providing a look into the system's past, and the planet's
mysterious interior.
Page 8 AGS September 2017
After A Dive Into Saturn, Cassini Spacecraft Melts Into History (Continued)
Rethinking Saturn
Cassini’s final 22 orbits have already made clear that scientists’ understanding of Saturn’s atmosphere and
interior need rethinking. Insights into the planet’s magnetic field, mass, rings, and mysterious interior are still to
come, some collected by the eight instruments that remained operating during its final descent. This research
will be the culmination of a campaign that went better than many could dream, says JPL’s Dennis Matson, who
served as the project scientist on Cassini from its conception until 2010. “Before we got to Saturn, I didn't
expect it—I thought it’d be like Galileo at Jupiter,” he says. “I didn’t expect it to be a paradigm reset of
everything.”
Science is not Cassini’s only legacy. It serves as the model for collaboration among disciplines and nations in
planetary science, with its instrument teams featuring balanced rosters of U.S. and European scientists. JPL’s
upcoming $2 billion Europa Clipper mission will borrow its orbital innovations to dodge Jupiter’s fierce
radiation, and Cassini’s scientists are migrating to missions proposed or underway to Jupiter’s moons; the ice
giants Neptune and Uranus; or back to Saturn’s moons, this time armed with new tools to search for life. There
are lesser known legacies, too: In 2003, Cassini provided the best validation of general relativity. Tools
developed in the 1990s to swap money among Cassini’s scientific instrument teams went on to run emissions
trading to reduce smog in southern California. The list is long.
But most of all, Cassini will be remembered for the moons. Thanks to the spacecraft, along with its long-lost
probe, Huygens, two of Saturn’s moons, Enceladus and Titan, have now become prime candidates in the search
for life. Cassini revealed Enceladus, once thought small, cold, and dead, to have more than 100 plumes of
hydrogen-rich liquid water erupting from cracks in its icy crust, possible evidence of hydrothermal vents in its
buried sea—a habitat similar to Earth. In one stroke, it has expanded the boundaries of the habitable zone, both
for our solar system and exoplanets beyond. Meanwhile, on hazy Titan, Huygens and Cassini found an Earth-
like landscape of rivers and lakes filled with liquid methane—the only liquid bodies found on the surface of
moon or planet in the solar system, except Earth.
On Titan, Saturn's largest
moon, scientists found a rich
terrain carved by liquid
methane, a realm that may
resemble prebiotic Earth.
AGS September 2017 Page 9
After A Dive Into Saturn, Cassini Spacecraft Melts Into History (Continued)
A Model of Reliability
Cassini had become a model of reliability as it swung from orbit to orbit around Saturn, in a path that resembled
a complex ball of yarn designed to maximize its lifetime, its shifts governed by Titan’s gravity. The spacecraft’s
longevity has not just been luck; from the start, its engineers shorn it of moving parts prone to failure. And
although some instruments on its 2-ton, bus-sized body have faced trouble—one of its two magnetometers
failed soon after it arrived at Saturn, necessitating intricate rolls to calibrate it—most have metronomically
continued as Saturn’s seasons shifted from spring to summer solstice during its 29.5-year orbit.
While Enceladus and Titan stole the show, Cassini, on its way to taking a total of more than 450,000 images,
documented the intricacies of Saturn and its orbiting rings and moonlets. It captured a surprise storm on
Saturn’s otherwise placid taupe surface, arriving nearly a decade earlier than expected. It showed the persistent,
hexagonal jet stream on Saturn’s north pole, first hinted at by Voyager. And its probing of waves in the planet’s
rings allowed a window into Saturn’s interior and history.
But many revelations have been delayed until Cassini’s final orbits, which NASA dubbed its Grand
Finale. Starting in April, the spacecraft began plunging once a week between Saturn and its rings, its closest
look at each. The mysteries started early; during its first orbit, Cassini wielded its large radio antenna like a
shield to protect itself from possible ring particles. But there were almost none in the gap, a puzzling absence.
“We’re all still struggling to understand that,” says Matt Hedman, a planetary scientist at the University of
Idaho in Moscow.
Perhaps most important were six runs maximized for Cassini’s radio science experiment. As the spacecraft
plunged through these orbits, a radio telescope in Argentina, run by the European Space Agency, NASA’s
partner on the mission, listened for tiny Doppler shifts in Cassini’s signal. Previously, Saturn’s rings and planet
were inextricably bound up in this measure. But by threading the needle, Cassini has allowed scientists to
untangle them, telling them about the mass, and therefore age, of the rings—and uncloaking Saturn’s interior.
Scientists are not yet ready to settle the long debate over the rings’ age; a definitive statement on whether
they’re 100 million or billions of years old could come later this year. But the finale has already made clear that
the interior and exterior of Saturn rotate at different rates, with a significant difference in speeds, Iess says. A
similar pattern is seen in the sun, but NASA’s Juno spacecraft, now orbiting Jupiter, has found only a marginal
difference in rotation in its gas giant. Something more complex is going on at Saturn, adds Jonathan Fortney, a
planetary scientist at the University of California, Santa Cruz; it appears one template does not govern gas
giants. “Saturn is not a small version of Jupiter,” he says. “The planets are distinct and unique.”
Measuring the Magnetic Field
The final orbits also saw Cassini take its finest measures of Saturn’s magnetic field. Lacking any fixed surface
features to measure, scientists still don’t know whether a Saturn day lasts 10.6 or 10.8 hours. Regular bursts of
radio waves that made it possible to know Jupiter’s day have proved irregular on Saturn. This close look could
resolve the day length and another mystery: why it appears that the axis of Saturn’s magnetic field is perfectly
aligned with its rotation; scientists had thought a slight offset between the two is necessary to maintain such a
Page 10 AGS September 2017
After A Dive Into Saturn, Cassini Spacecraft Melts Into History (Continued)
field, as seen on Earth and other planets.
More answers await: By combining their gravity and magnetic measures, Michele Dougherty, a space physicist
at Imperial College London, also expects to reveal new information about the composition and mass of Saturn’s
core, along with some sense of how the heavier elements distribute among the gas giant’s stew of hydrogen and
helium. But this will take time, which had been sparse when orbits were coming every week. That’s why,
beyond pride and sadness, she says, “There is also a little bit of relief. Because we’re all exhausted now.”
As it neared its end, Cassini also made close study of Saturn’s rings, which are largely made up of water ice—
including, for the first time, the capture of a few stray, submicron particles. “We have measured the ring
directly,” says Nicolas Altobelli, Cassini’s project scientist at the European Space Agency in Madrid. But once
Cassini dipped its toes into Saturn’s atmosphere during its final orbits, the ring grains disappeared, surprising his
team. Altobelli isn’t sure whether this absence is due to an unknown atmospheric dynamic—or his instrument’s
inability to operate outside the vacuum it was designed for.
Cassini also captured the closest images of the rings, down to clumps of the particles. These pictures have
revealed distinct, hidden structures in rings that otherwise have the same density and composition, with stark
differences in reflectivity. “It’s like how an ice cube has a different texture from a snowball,” says Matthew
Tiscareno, a ring specialist at the SETI Institute in Mountain View, California. There’s no moon or other force
they know of that could cause such bands. “There are hints it may have to do with the structure in the planet,” he
adds.
Read more at http://www.sciencemag.org/news/2017/09/after-dive-saturn-cassini-s-melts-history
“Solar System Graveyard” Where spacecraft go to die. Into the great beyond Dozens of spacecraft have been
sent out across the solar system. Many still orbit their target worlds. But 42 are known to have final resting
places on other planets. Where did these robotic explorers go? Who sent them? And how did they die? Find out
more by clicking on this interactive link: http://vis.sciencemag.org/space-graveyard/
What Could Have Created The Ancient Martian Rivers?
Water is essential for life. When searching for life in the universe, the first thing researchers do is “follow the
water”. Mars is no exception. Finding evidence of water on Mars could put scientists one step closer to finding
out if there is or was life on the red planet. Some exploration and reconnaissance missions sent by NASA to
Mars, as old as Mariner 9 and the Viking Mission in the 70’s, have already collected evidence of water flowing
on the surface, which can be observed by the formation of soil patterns (pictured to the left). On Earth, these
processes are caused by rainfall and the activity of rivers and lakes, where the action of running water causes
soil erosion and eventually forms valleys.
However, in order to have liquid water, some conditions are needed, like an average temperature above the
freezing point 0°C or 273 K, approximately). On Earth, liquid water is possible due mainly to the temperature
that our planet sustains. Unfortunately, Mars does not have the same climate conditions, due to its thin
atmosphere and distance from the Sun. The thin atmosphere prevents the planet from having enough of one of
the main natural process that helps Earth to keep warm: the greenhouse effect.
AGS September 2017 Page 11
What Could Have Created The Ancient Martian Rivers? (Continued)
Scientists have made some climate models to explain how liquid water on Mars could be possible and, at the
same time, explain the observation of these activities in the soil of Mars. Some hypotheses already raised by
other researchers include the possibility that Mars was originally icy and occasionally heated by impacts or
volcanic activity. Another hypothesis is that Mars was once heated due to the presence of gases that enabled the
greenhouse effect. However, these theories cannot explain how the planet could have maintained the necessary
temperature to have liquid water for the period needed to form the valleys and patterns observed. In addition, the
Sun was approximately 25% less bright by the time most of the valleys were formed, which makes it even more
difficult to warm the planet.
The new model proposed in this study suggests cycles of hot and cold periods, caused by the presence of carbon
dioxide (CO2) and hydrogen gas (H2) in the atmosphere, which could increase the greenhouse effect in the
necessary amount. Carbon dioxide alone wouldn’t be enough to cause the necessary warming of the surface. The
larger amounts of hydrogen gas in the atmosphere would more efficiently absorb the “heat” of the Sun. The
combination of the two gases would cause the surface temperature of Mars to become warm enough to have
liquid water instead of ice. Scientists say the hot and cold periods are due to the activity of volcanoes on Mars.
They release carbon dioxide and hydrogen gas into the atmosphere, which then reacts with rocks on the ground
to form minerals known as silicates. When the planet is in its icy period, the amount of CO2 released in the
atmosphere by the volcanoes is higher than what is converted into silicates. So, the amount of carbon dioxide in
the atmosphere increases, helping to produce a thicker atmosphere and, consequently, warming up the planet.
With the heating of the planet, the ice is melted, turning into liquid water.
Incidentally, the increasing heat helps the silicates to rapidly consume the carbon dioxide, so the amount of CO2
in the atmosphere starts to decrease, even with the volcano’s activity. As the CO2 in the atmosphere drops, the
planet starts to get colder and the liquid water turns into ice again and the cycle repeats. The valleys observed
would have formed a little more each time the planet warms. Discovering the origin of the formation of these
valleys can help answer questions about the early conditions on Mars. Future missions will seek to determine
how long ago these valleys formed by analyzing the soil. Perhaps we will be closer answering whether or not
life is or was possible on the planet.
Read more at http://sciworthy.com/what-could-have-created-the-ancient-martian-rivers/
Patterns on the surface of Mars
similar to deltas on Earth caused
by flowing water. Image By
NASA/JPL/Malin Space Science
Systems [Public domain], via
Wikimedia Commons.
Page 12 AGS September 2017
Unusual Mexico Earthquake May Have Relieved Stress In
Seismic Gap
When Vlad Manea heard about the deadly magnitude-8.2 earthquake that struck the coast of Mexico’s Chiapas
state on 7 September, he was stunned, but not altogether surprised. A geophysicist at the National Autonomous
University of Mexico (UNAM) in Juriquilla, Manea is one of only a handful of earth scientists who study
seismic activity in the region. For more than a century, there had been little activity to study—precisely why
Manea thought the area could be due for a big one.
The epicenter of the quake, which struck just before midnight local time, was just southeast of the Tehuantepec
gap, a 125-kilometer-long stretch of Mexico’s Pacific coast that has been seismically silent since record-keeping
began more than a century ago. All along that coast, the ocean’s tectonic plates meet the continental North
American plate and are forced underneath it. Violent earthquakes mark the release of built-up pressure between
the grinding plates. But the ruptures have somehow avoided the Tehuantepec gap and the Guerrero gap, more
than 500 kilometers to the northwest.
For decades, scientists have monitored the Guerrero gap because of its proximity to Mexico City. A rupture
there could devastate the capital, which is built on a drained lakebed that amplifies seismic waves. In 1985, a
magnitude-8.1 quake near the Guerrero gap killed thousands, spurring the city to install a seismic alert system
and tighten building codes. Those measures seemed to help last week: The capital sustained little damage in
spite of considerable shaking.
The Tehuantepec gap has received far less attention. “It was considered the little brother,” says Manea, who
began studying it in the early 2000s along with his wife, UNAM geophysicist Marina Manea. Their first priority
now is to figure out how much of the Tehuantepec gap slipped in last week’s quake, which killed more than 90
people and destroyed or severely damaged the homes of 2.3 million more, mostly in the states of Chiapas and
Oaxaca. Although the epicenter was just outside the gap, more than 1000 aftershocks have been recorded, many
in the gap itself. Vlad Manea says some of them may have been strong enough to release stored pressure and
close the gap—which would make future quakes in the region less likely.
AGS September 2017 Page 13
Unusual Mexico Earthquake May Have Relieved Stress In
Seismic Gap (Continued)
He concedes, though, that the quake’s effect on the gap is hard to judge, because of its unusual origin. Most big
Mexican earthquakes occur right along the interface between the colliding Cocos and North American plates.
But this rupture began 70 kilometers down, within the Cocos plate itself, and rose up before stopping at about 40
kilometers’ depth, likely at the plate interface. “It’s not the same fault that they’re expecting [to close] the
Tehuantepec gap,” says Joann Stock, a seismologist at the California Institute of Technology in Pasadena.
That leaves the future risk of the Tehuantepec gap unclear. In fact, Stock says, last week’s quake might have
even added stress at the gap and increased chances for future slipping. But, she adds, the depth of the shaking
had at least one benefit: The rupture didn’t break through all the way to the ocean floor, which dampened
tsunamis. The resulting waves in Chiapas and Oaxaca were only 2 to 3 meters high.
Vladimir Kostoglodov, a seismologist at UNAM in Mexico City, says he is fielding requests for data from
researchers around the world who want to investigate this “extremely strange” earthquake and its aftermath. “It’s
worth making a big effort to learn what’s happening,” he says. “This might happen in other subduction zones in
other parts of the world.”
Read more at http://www.sciencemag.org/news/2017/09/unusual-mexico-earthquake-may-have-relieved-stress-seismic-gap
There Are More Than 300 Kinds Of Ice, Scientists Report
The ice on the surface of planet Earth—the kind we’re all familiar with—has a hexagonal crystal structure. High
in the atmosphere it’s possible to find cubic ice. Aside from that, scientists have never found any other
arrangements for solid water in the natural world, but that doesn’t mean they’re not possible: A new study in The
Journal of Chemical Physics has revealed that there could be as many as 300 different molecular arrangements
for ice. According to New Scientist, most of the new versions are based around reorganizing a known structure of
low-density ice called zeolitic ice, however the super–low density structures can only exist at extremely low
pressures and temperatures close to absolute zero, so you’ll be more likely to find them on another planet than in
your drink anytime soon.
Read more at http://www.sciencemag.org/news/sifter/there-are-more-300-kinds-ice-scientists-report
Page 14 AGS September 2017
The World Is Running Out Of Sand — And You’d Be Surprised How
Significant That Is
China has devoured more sand in the past four years than the United States did throughout the 20th century.
Dubai, a city built on a desert, had to import the sand used in the world’s tallest tower, the Burj Khalifa, from
Australia. In India, sand has become such a hot commodity that it has been taken over by “sand mafias” who
illegally mine and sell it on the black market.
The demand for sand is on the rise as urban development around the world soars and hydraulic fracturing
technology becomes more popular in places such as the U.S. and Alberta. Though most people have never
thought twice about the supply of the seemingly plentiful grains, a growing number of observers are ringing the
alarm that the global supply of sand is slipping through our fingers. Sand and its larger cousin, gravel, are better
known in the industrial realm as “aggregate,” the key ingredients in concrete, asphalt and glass used in
everything from highways to skyscrapers.
The demand for construction aggregates will rise 5.2 per cent annually to 51.7 billion tons in 2019, according to
researcher Freedonia Group. Some estimate sand’s share of the aggregate business is already worth US$70
billion in annual sales. A 2014 United Nations Environment Programme report, Sand, Rarer Than One Thinks,
determined that sand and gravel mining accounts for as much as 85 per cent of all mining activity in the world
and concluded that the depletion rate of sand is rapidly exceeding its natural renewal rate worldwide.
As a result, some Canadian sand companies are booming due to an increase in demand for oilsands fracking and
exports to markets that have already depleted their supplies. At the same time, industry players in some areas
such as Greater Toronto Area (GTA) are warning about a shortage of the construction staple not because of
demand-driven depletion, but because of local opposition to getting it out of the ground.
Decades of rapid urbanization and suburbanization in the GTA have put residents ever closer and closer to sand
and gravel quarries and pits that once seemed relegated to the rural outskirts. Residents associations have banded
together to try to stop new quarries and pits from being built on the edge of their backyards.
They’re worried about air and noise pollution as much as the effect on their property values. Greg Sweetnam the
executive vice-president of James Dick Aggregates is seen at the Caledon Sand and Gravel pits in Caledon, Ont.
Sweetnam, who has worked for his father-in-law’s family-run operation for 37 years, gets frustrated when he
talks about the predicament his company is in with its neighbours. He just doesn’t understand their logic,
especially if they want to cloak their concerns in environmentalism. The industry believes keeping supply local
is both more cost effective and environmentally friendly than shipping material from hundreds of kilometres
away. But building new quarries in the GTA, home to many high-quality deposits, has been nearly impossible
due to what Sweetnam said is simple “NIMBYism.” The showdown between neighbours is likely to escalate as
the GTA’s population growth spurs demand for the sand and gravel needed for new houses, schools and office
buildings. “Everybody uses aggregate,” Sweetnam said during a recent tour of James Dick Construction’s sand
and gravel pit in Caledon,
“We drive on it, we live inside it, we work inside it, we even brush our teeth with it and at some point we have to
understand that we all have to accommodate this.” The Ontario Stone Sand and Gravel Association (OSSGA)
has decided to fight back against vocal anti-quarry opponents with a “buy local” public awareness campaign.
Posters, already up in downtown Toronto bus stops, try to educate city dwellers who are largely unaware of both
the importance of sand to their infrastructure and the issues it is causing in nearby townships.
AGS September 2017 Page 15
The World Is Running Out Of Sand — And You’d Be Surprised How
Significant That Is (Continued)
Such opposition has shut down three applications for new pits and quarries in the past decade and has led to a
shortage of local sand that, of course, built the homes that house even the most vocal opponents, said Greg
Sweetnam, vice-president of James Dick Construction, which operates a pit in Caledon, Ont., about 75
kilometres outside downtown Toronto. Sand had to be imported to build Dubai’s Burj Khalifa. The organization
said local opposition or NIMBYism has worked its way into government processes that have become more
rigorous in recent years. It said the provincial government’s new review and consultation process is drawing out
the permitting process for new pits and quarries to between five and 10 years.
At the same time, the government has also limited prospects for new pits and quarries by expanding protected
areas that are off limits to development, said OSSGA executive director Norman Cheesman. “We continue to use
resources faster than we’re replacing them,” he said. “It’s going to become a challenge. We’re going to have to
be going further afield to get that aggregate and that means higher costs.” Those costs will likely be passed down
the supply chain to builders, developers and homeowners. Transportation comprises 50 to 60 per cent of the cost
of aggregates. And that — not the environment — is why the industry is so intent on keeping pits close to
residential areas, said Bob Shapton, spokesman for Pitsense, an anti-aggregate development group and 30-year
neighbour of James Dick Construction’s sand and gravel operations.
The aggregate industry, he said, is in the business to make money. There’s nothing wrong with that, he said, but
the neighbours also have a monetary interest in their property and the company needs to accommodate them.
“The neighbours adjacent to any of these developments are suffering from the prospect of health impacts and the
prospect of the certainty of the diminution in property values which the operators deny,” Shapton said. The
neighbours, he added, would be more likely to be on board if the operators that are proposing new sites would be
willing to compensate residents for the potential to hurt their property values as well as for any social and health
impacts. “There are ways that people can get along and there should be no losers.”
Read more at http://google.com/newsstand/s/CBIwzriR8jU
Page 16 AGS September 2017
Upcoming Field Trip
ANNOUNCING 2017 GGS FIELD TRIP OCT. 6-8
We are excited to announce that this year's Georgia Geological Society field trip will be led by Clint Barineau
(Columbus State) and Jim Tull (Florida State) and will address the tectonic setting and correlation of Taconic
backarc and arc terranes in the Inner Piedmont and Talladega belts of west Georgia and Alabama. The meeting will
be held from October 6-8 (weekend before Columbus day) with headquarters at the Best Western Inn in Carrollton.
For additional details on the itinerary and registration please check out our website at: https://www.westga.edu/~ggsweb/fieldtrip/fieldtrip2017.html. The Social will be held on Friday evening October
6, 7:00-10:00 pm and will be hosted in the Department of Geosciences at the University of West Georgia. Join us
to catch up on what your colleagues have been up to over the last year and to learn about the latest geologic work
in the Piedmont.
AGS September 2017 Page 17
September AGS PG Workshop Announcement
Date: September 30, 2017 Time: 10:00am to 12:00pm
Venue: Fernbank Science Center Annex (check with the receptionist to see which room we will be in)
156 Heaton Park Drive,
N.E. Atlanta, GA 30307
678-874-7102
http://fsc.fernbank.edu/
Speaker: Dr. Jim Kennedy, PhD, PG
Subject: Aspects of Groundwater Hydrology Contaminant Hydrogeological Behavior
Dr. Kennedy will cover different aspects of groundwater hydrology, definitions, and applications of
principles to define a hydrological system. He will also discuss various aspects of chemicals and their
behavior in groundwater flow systems. Jim is the State Geologist of Georgia and holds B.S. and M.S.
degrees in physics and geophysical sciences from Georgia Tech and a Ph.D. in geology from Texas A&M
where he did research on reclaimed lignite mines. As State Geologist, he has worked on the Coastal
Sound Science Initiative to manage salt-water intrusion into the Upper Floridan aquifer, permitting of
coastal groundwater supply wells, and the State Water Plan. He also has provided expert testimony at the
Office of State Administrative Hearings in support of landfill, quarry, and water withdrawal permits
issued by the Georgia Environmental Protection Division. Prior to joining the EPD, Dr. Kennedy worked
as a consultant and conducted engineering geology, groundwater supply, and environmental remediation
projects in various areas of the United States and Europe.
Please join us and forward this message to anyone interested in becoming a Georgia Registered
Professional Geologist, or anyone who might be interested in the topic. Two Professional Development
Hours are available for attendees of the class. The classes are open to all, membership in the AGS is not
required, but for $25/year ($10 for students), it is quite a bargain! Please consider joining, the AGS is one
of the most active geological organizations in the Southeast.
For more information on becoming a member, visit www.atlantageologicalsociety.org. Contact us at the
addresses below if you have questions about the workshop or the exams. An application form is attached.
Thanks,
Atlanta Geological Society
Professional Registration Committee
Ken Simonton, P.G. [email protected]
Ginny Mauldin-Kinney, P.G. [email protected]
Page 18 AGS September 2017
Fernbank Events & Activities
Treetop Tales Saturday, September 23, 2017 Bring your preschoolers for
storytelling and special activity with a
Fernbank educator.
Learn more
Gladiator Day Saturday, September 30, 2017 Enjoy live gladiator demos, Roman-
themed crafts, ancient architectural
activities and more.
Learn more
A Timeless Affair 2017: Gladiators Saturday, October 7, 2017 Don’t miss Fernbank’s signature black-
tie gala. All proceeds benefit educational
programming at the Museum.
Learn more
Free Photography Presentation Sunday, October 1, 2017 Learn more about National Geographic
photographer Peter Essick’s 2-year
project documenting Fernbank Forest.
Learn more
AGS September 2017 Page 19
Wildwoods and Fernbank Forest WildWoods features 10 acres of lush woodlands,
highlighted by hands-on exhibits for all ages, tree
pods suspended in the canopy, a nature gallery,
immersive adventures, and meandering trails
emphasizing dramatic slopes and stunning
views. This interpretive nature experience serves as
the new entrance into Fernbank Forest.
Learn more
Wild Huts and Hollows On view September 9 – February, 2018 Explore a variety of woven sculptures by mixed media
artist, J.D. Koth. This special exhibit will feature archways
and huts of various sizes, all constructed using locally-
harvested plant material and designed to spark the
imagination and curiosity of both kids and adults. Visitors
will be invited to explore many of the woven sculptures
inside and out, offering guest unique photos opps.
Learn more
Page 20 AGS September 2017
Now showing in the Fernbank IMAX movie theater:
National Parks Adventure 2D August 28 – September 29, 2017 Experience the ultimate off-trail adventure into the nation's awe-inspiring great outdoors and untamed wilderness in this
film, perfect for families and adrenaline junkies alike. Follow modern-day explorers as they explore spectacularly wild and
beautiful places, including Yellowstone, the Everglades and the Redwoods. National Parks Adventure 2D will inspire the
adventurer in all of us while celebrating the majesty of our national parks and treasures landscapes.
Amazon Adventure 3D May 20 – September 29, 2017 Experience the epic, true story of explorer Henry Bates' fascinating 11-year journey through the Amazon rainforest as a
young man working to unravel a great scientific mystery. As in any great detective story, audiences will experience the
compelling clues Bates unearths in his major discovery of the phenomenon of “Batesian” mimicry, whereby certain
animals adopt the look of others and thus can deceive predators and prey. Little known to the public, Bates made other
crucial contributions to biology: identifying 8,000 species new to science and most importantly, putting the first ever case
for the creation of a new species, which Charles Darwin called the “beautiful proof” for Natural Selection. See mind-
boggling examples of camouflage and mimicry in the visually stunning and biodiverse Amazon. You’ll be inspired by
Bates' endless curiosity and determination to explore the wilds of nature.
Fernbank Museum of Natural History (All programs require reservations, including free programs)
AGS September 2017 Page 21
AGS Committees
AGS Publications: Open
Career Networking/Advertising: Todd Roach
Phone (770) 242-9040, Fax (770) 242-8388
Continuing Education: Open
Fernbank Liaison: Kaden Borseth
Phone (404) 929-6342
Field Trips: Open
Georgia PG Registration: Ken Simonton
Phone: 404-825-3439
Ginny Mauldin-Kenney,
ginny.mauldin@gmailcom
Teacher Grants: Bill Waggener
Phone (404)354-8752
Hospitality: John Salvino, P.G.
Membership: Burton Dixon
Social Media Coordinator: Carina O’Bara
Newsletter Editor: James Ferreira
Phone (508) 878-0980
Web Master: Ken Simonton
www.atlantageologicalsociety.org
AGS 2017 Meeting Dates
Listed below are the planned meeting
dates for 2017. Please mark your calendar
and make plans to attend.
2017 Meeting Schedule
September 26 Speaker Dr. Katayoun
Mobasher from N. Georgia University
October 31 Halloween Party
November 28 Speaker Dr. Stephen
Henderson from Emory University
December 26 No Meeting
January 30
PG Study Group meetings Contact Ken Simonton for the details.
September 30
October 28
November 25
December 30
January 27
AGS Officers
President: Ben Bentkowski
Phone (770) 296-2529
Vice-President: Steven Stokowski
Secretary: Rob White
Phone (770) 891-0519
Treasurer: John Salvino, P.G.
Phone: 678-237-7329
Past President
Shannon Star George
Page 22 AGS September 2017
ATLANTA GEOLOGICAL SOCIETY
www.atlantageologicalsociety.org
ANNUAL MEMBERSHIP FORM
Please print the required details and check the appropriate membership box.
DATE:_____________________________________________
NAME:____________________________________________
ORGANIZATION:____________________________________________________________
TELEPHONE (1): TELEPHONE (2):
EMAIL (1): EMAIL (2):
STUDENT $10
PROFESSIONAL MEMBERSHIP $25
CORPORATE MEMBERSHIP $100 (Includes 4 professional members, please list names and emails below)
NAME: EMAIL:
NAME: EMAIL:
NAME: EMAIL:
NAME: EMAIL:
For further details, contact the AGS Treasurer:
John Salvino [email protected]
Please make checks payable to the “Atlanta Geological Society” and bring them to the next meeting or remit
with the completed form to:
Atlanta Geological Society, Attn: John Salvino
3073 Lexington Avenue
Woodstock, Georgia 30189
To pay electronically; click
https://squareup.com/store/atlanta-geological-society
CASH CHECK (CHECK NUMBER:___________)