Stories tagged Earth and Space Science

Jun
09
2014

Plastiglomerates: Characteristics of the two types of plastiglomerate. (A) In situ plastiglomerate wherein molten plastic is adhered to the surface of a basalt flow. Field book is 18 cm long. (B) Clastic plastiglomerate containing molten plastic and basalt and coral fragments. (C) Plastic amygdales in a basalt flow. (D) Large in situ plastiglomerate fragment. Adhered molten plastic was found 15 cm below the surface. Note the protected vegetated location.
Plastiglomerates: Characteristics of the two types of plastiglomerate. (A) In situ plastiglomerate wherein molten plastic is adhered to the surface of a basalt flow. Field book is 18 cm long. (B) Clastic plastiglomerate containing molten plastic and basalt and coral fragments. (C) Plastic amygdales in a basalt flow. (D) Large in situ plastiglomerate fragment. Adhered molten plastic was found 15 cm below the surface. Note the protected vegetated location.Courtesy Patricia L. Corcoran
Geologists have always considered rocks to be plastic because they are often reformed, remelted, and reshaped by tectonic forces such as heat and pressure. But now, earth scientists have declared a new type of rock they're calling plastiglomerates. It's a composition of volcanic rock and actual plastic, or a clump of rock, sand, coral and seashells all held together by a mass of melted plastic derived from human debris.

Considering we humans have been generating heaps of plastic waste since the middle of the last century (and enough to wrap up our entire planet in plastic) it's no wonder some of it has managed to find its way into the rock cycle. It's only surprising that it took us this long to notice it.

Chunks of plastiglomerate were found recently at a beach in Hawaii. Patricia Corcoran, a geologist from the University of Western Ontario, and Charles Moore, captain of the research vessel Alguita discovered plastiglomerates at 21 different sites they surveyed on Kamilo Beach located on the southern tip of the Big Island of Hawaii. Their study appears in the latest issue of GSA Today.

Kamilo Beach on the Big Island of Hawaii: the red dot marks beach's approximate location.
Kamilo Beach on the Big Island of Hawaii: the red dot marks beach's approximate location.Courtesy NASA
Kamilo Beach is an isolated location that, due to ocean currents and trade winds, and its location, has long been a magnet for plastic and other trash floating on the Pacific. In the distant past, native Hawaiians collected wood from Kamilo that had floated in from the Pacific Northwest to make dugout canoes. There's no easy access to the beach - it's usually void of beach-goers and takes a two hour four-wheel drive over a jagged lava field just to reach it. But each year, 15 to 20 tons of all sorts of floating plastic - from toothbrushes to water bottles to toy green army men - pile up on the rocks and sand of Kamilo. It's not the only place of course, plastic debris has been found in different areas of ocean bottom around the world. It's not surprising that some of it ends up joined with other elements to form the new rock.

Plastiglomerates are thought to have formed probably from plastic melted in beach campfires or in lava flows, which aren't unusual on the Big Island. In the distant future, as plastic gets further buried under layers of future sedimentation or lava flows, it will likely become even more incorporated, melting and re-melting under extreme heat or pressure and filling in cracks and crevasses in the country rock much like minerals such as quartz and pyrite have done in the past. Tens or hundreds of thousands of years from now, future geologists will no doubt be able to use these traces as markers for the Anthropocene era, the name gradually gaining acceptance to describe humanity's post-agricultural or industrial time on the planet.

SOURCE and LINKS
Science (AAAS) story
LiveScience story

May
19
2014

Early dinosaur hyperbole: New York newspaper from December, 1898
Early dinosaur hyperbole: New York newspaper from December, 1898Courtesy Public domain
The Internet has been all a-buzz lately about the largest dinosaur - EVER - being discovered in Argentina. The beast is massive - equal to 14 elephants and as long as two tractor trailers! The story's accompanying photo (several, in fact) often shows an adult man laid out next to a gigantic titanosaur femur. Pretty impressive, at least at first. But the problem I had was finding out some idea of how long the bone was or how tall the man was. It's all relative, of course. It reminds of one of my favorite W. C. Fields scenes is in the movie YOU CAN'T CHEAT AN HONEST MAN where he plays a carnival barker at a sideshow touting the World's Largest Midget and the World's Smallest Giant, and featuring two guys of average height.

Giant dinosaur bone = giant guy: Evidently, Bill Reed was a big, big man
Giant dinosaur bone = giant guy: Evidently, Bill Reed was a big, big manCourtesy Public domain
This kind of hyperbole has been around ever since dinosaurs were first discovered. If the bone pictured in the 1898 New York Advertiser article is as large as the caption claims, then the man standing next to it, William Harlow Reed, is eight feet tall as well(!) - an equally if not more impressive story that the newspaper obviously overlooked.

It should be noted that the sensational discovery was the catalyst for steel magnate Andrew Carnegie to spend lots of money to get himself his own dinosaur (Diplodocus carnegiei) in 1899. It wasn't quite as large as the one that inspired his quest but casts of Carnegie's dinosaur were given to various foreign heads of states, helping spread dinosaur fever to the world.

SOURCES and LINKS
BBC story
Geo Scienze blog (in Spanish)
CNN story
Everything Dinosaur blog
Sauropod Vertebrate Picture of the Week

May
12
2014

Pterodactylus ancestor discovered
Pterodactylus ancestor discoveredCourtesy Mark Ryan
Over in China, out of one of the richest hunting grounds for new and unusual dinosaur-era fossils, the earliest known member in the family of flying reptiles known as pterosaurs has been described in a paper published in Current Biology.

Named Kryptodrakon progenitor, the ancestral pterodactyloid was discovered in mudstones in the highly fossiliferous Shishugou Formation of northwest China by a team of international paleontologists.

The flying reptile's name essentially means "first-born hidden serpent", the genus name Kryptodrakon referring to the popular martial arts film, "Crouching Tiger, Hidden Dragon" which was filmed near the location where the fossil was discovered in the Chinese autonomous region known as Xinjiang.

Sporting a wingspan of some 4.5 feet, Kryptodrakon lived in a floodplain environment during the Middle-Upper Jurassic period, about 163 million years ago. Descendents of the newly-discovered pterodactyloid would evolve into much larger flying reptiles such as the giant, Cessna-sized Quetzacoatlus found in Late Cretaceous sediments in Texas. Pterosaurs were not dinosaurs but share a common ancestor with them.

The research increases our knowledge of pterosaur development and was led by Brian Andres from the University of South Florida (USF), James Clark of George Washington Columbia College of Arts and Sciences, and Xu Xing of the Chinese Academy of Sciences.

SOURCES and LINKS
Science Daily story
Pterosaur page
Paper in Current Biology

Apr
25
2014

Charlie Matsch: the Minnesota geologist and professor emeritus (right) explains Duluth geology to GSA field trip participants in 2011.
Charlie Matsch: the Minnesota geologist and professor emeritus (right) explains Duluth geology to GSA field trip participants in 2011.Courtesy Mark Ryan
I was saddened to hear of the death of Charlie Matsch, a well-known geologist, author, and highly-regarded professor emeritus at the University of Minnesota-Duluth. According to his obituary, Matsch was born in 1930, and graduated with a degree in geology from the University of Maine, and Master of Science degree from the University of Minnesota. After a stint as a petroleum geologist in Midland, Texas, Matsch acquired his Ph.D from the University of Wisconsin, then joined the Geology Department at UMD where he served as teacher and mentor to both undergraduate and graduate students, until he retired from teaching in 2001. Matsch helped co-write the classic book, Minnesota Geology, with geologist Richard Ojakangas (my geology instructor when I attended UMD).

I met Charlie Matsch only once, back in the autumn of 2011, as part of a Geological Society of America field trip in Duluth. The GSA was holding their annual meeting in Minnesota that year, and I was fortunate enough to attend with a media pass. Besides entry into the conference, the pass also gave me the opportunity to sign up for a field trip to Duluth. The excursion was comprised of a half day on Lake Superior aboard the research vessel, Blue Heron, and a half day with Charlie Matsch exploring some of Duluth's geological highlights.

Charlie was very pleasant, open, and easy going. In the course of our conversation, it came up that several years before I had written a history of Duluth's parks and boulevards, and that one of my favorites was Seven Bridges Road, a local and historic parkway running up the western branch of the Lester River, not far from where I grew up. Charlie's eyes lit up. He said Seven Bridges Road was one of his favorite places in Duluth.

During his segment of the field trip, you could tell Charlie was really passionate about geology as he explained the dark gabbro intrusion outcropping on top of the hill near Duluth's landmark Enger Tower, or the black sand sedimentary layers interlaced between basalt flows along Lake Superior's shoreline.

At the Deeps: Geologist Charlie Matsch (center in green cap) explains the geological events that formed the natural popular swimming hole seen in the background.
At the Deeps: Geologist Charlie Matsch (center in green cap) explains the geological events that formed the natural popular swimming hole seen in the background.Courtesy Mark Ryan
Between those stops, Charlie took us up to one of my favorite spots in Lester Park to see a spectacular waterfall that has carved a beautiful, natural swimming hole out of the billion year old basalt flows that make up much of Duluth's rocky bluffs (along with the aforementioned gabbro). The idyllic setting, known as "The Deeps", was one of my hangouts while growing up in Duluth. Not surprisingly, it's located just off Seven Bridges Road.

Charlie's research focused on Minnesota geology, and the effects of the ice age in the Midwest. It's no surprise to learn that Charlie Matsch passing occurred April 18 while he was attending the annual Geological Sciences Banquet and Awards Ceremony, an event he never missed.

A celebration of Professor Matsch's life will be held 6pm-9pm, May 9, at the Tweed Museum of Art at UMD in Duluth.

SOURCES and LINKS
Duluth News Tribune obiturary
UMD biography

Apr
13
2014

Tiktaalik roseae: Field Museum of Natural History
Tiktaalik roseae: Field Museum of Natural HistoryCourtesy Eduard Solà via Wikipedia
If you missed last week's PBS broadcast of Your Inner Fish, the documentary based on paleontologist-anatomist Neil Shubin's book by the same name, you have another chance to catch up on the first of three segments on the web. It's an excellent opening segment of the 3-part series, but is only available (for free!) right here through April 23, 2014.

The series deals with Shubin's search for the connections we all have with our fishy and reptilian ancestors. His discovery of the remarkable transitional fossil named Tiktaalik roseae on Ellesmere Island in the Canadian Arctic has added great evidence of our ties with our distant piscean relatives. The flat-headed, 375 million year-old Tiktaalik possessed the exact features - such as both lungs and gills, a wrist and neck - that you'd hope to find in a transitional form between swimming fish and land-walking tetrapods.

The next episode, titled Your Inner Reptile airs Wednesday, April 16th on your local PBS station. It's on here in the Twin Cities at 9pm but check your local listing for times in your area.

In the meantime, watch the first episode, and read about some of the reaction to Shubin's find here, here, and here.

LINKS
University of Chicago Tiktaalik roseae page

Feb
17
2014

Kilauea at night: a massive magma chamber has been detected beneath the volcano's East Rift Zone.
Kilauea at night: a massive magma chamber has been detected beneath the volcano's East Rift Zone.Courtesy Mark Ryan
Researchers from the University of Miami Rosentiel School of Marine and Atmospheric Science have detected a new, massive magma chamber beneath Kilauea, the most active volcano in the world.

By analyzing seismic waves that traveled through the volcano, scientists from the school's geology and geophysics departments have been able to piece together a 3-dimensional velocity model of what's taking place deep below the volcano's caldera.

"It was known before that Kilauea had small, shallow magma chambers," said Guoqing Lin, lead author of the study. "This study is the first geophysical observation that large magma chambers exist in the deep oceanic crust below."

Located in oceanic crust between 5 and 6.8 miles beneath the volcano's East Rift Zone, the new chamber has been determined to be several kilometers in diameter. The seismic data also revealed that it's lava is composed of a slushy mixture of about 10 percent magma and 90 percent crystal.

According to co-author and professor of geology and geophysics, Falk Amelung, the information is useful in understanding magma bodies and a high priority for the researchers because of the possible hazards created by the volcano.

"Kilauea volcano produces many small earthquakes and paying particular attention to new seismic activity near this body will help us to better understand where future lava eruptions will come from," he said.
Kilauea has been active for more than 30 years and is located in Hawaii Volcanoes National Park on the Big Island of Hawaii.

The paper appeared in a recent edition of the journal Geology.

SOURCES and LINKS
Science News story
LiveScience story
2007 video of Kilauea erupting
More about Kilauea

Dec
28
2013

Restoration of Haplocanthosaurus: a Late Jurassic sauropod whose remains are found in Colorado, Utah, and Wyoming.
Restoration of Haplocanthosaurus: a Late Jurassic sauropod whose remains are found in Colorado, Utah, and Wyoming.Courtesy FunkMonk via Wikimedia Commons
The partial remains of a somewhat rare sauropod dinosaur have been discovered in Old Snowmass, near Aspen, Colorado. Paleontologist John Foster of the Museum of Western Colorado in Grand Junction said that fossils of a Haplocanthosaurus were found by college student Mike Gordon in 2005 on land owned by his mom and stepfather. If you remember, Snowmass was the site near Aspen where a large collection of mammoths, mastodons, and other Ice Age mammals were uncovered back in 2010. This latest discovery is about six miles from the other site but in a much, much older rock layer. Foster said the Lower Morrison Formation, from where Haplocanthosaurus remains were collected dates back to the Late Jurassic, about 155-152 million years ago.

It's a very exciting find because few specimens of Haplocanthosaurus exist. The first were also found in Colorado, in Garden Park near Canon City, by Carnegie Museum of Natural History paleontologists William H. Utterback and John Bell Hatcher in 1901. The type specimens (H. priscus and H. utterbacki) were described by Hatcher in 1903. The fossils were prepared under the direction of chief preparator, Arthur S. Coggeshall.

Mounted skeleton of Haplocanthosaurus delfsi: Cleveland Museum of Natural History
Mounted skeleton of Haplocanthosaurus delfsi: Cleveland Museum of Natural HistoryCourtesy ScottRobertAnselmo via Wikimedia Commons
Compared to its larger and heavier long-necked, small-headed cousins such as Apatosaurus and Diplodocus, the Haplocanthosaurus was a relatively small-sized sauropod dinosaur with a length of 35 to 40 feet and weighing maybe 14 tons. While most sauropods have hollow spaces in their backbones, a distinguishing characteristic of Haplocanthosaurus is the solidness of its vertebrae which Foster confirmed by doing a scan of the fossil bones at a local hospital in Grand Junction.

Haplocanthosaurus hindlimb: Science Museum of Minnesota
Haplocanthosaurus hindlimb: Science Museum of MinnesotaCourtesy Mark Ryan
The only mounted specimen of Haplocanthosaurus is the referred species (H. delphsi) on exhibit at the Cleveland Museum of Natural History in Ohio. No skull of the sauropod has ever been found so the head is just a fabricated guess. Other post-cranial remains exist, including some here at the Science Museum of Minnesota that were collected in Wyoming, but in general fossils of the dinosaur are rare. Material from only 10 individuals are known.

So far the Old Snowmass site has provided some vertebrae, ribs and a pelvis. but the landowners have been very accommodating in allowing the museum access to the dig site, and Foster hopes to find more Haplocanthosaurus bones - maybe even some skull material - in the coming summer season.

SOURCES and LINKS
Aspen Times story
More Haplocanthosaurus info
Osteology of Haplocanthosaurus by John Bell Hatcher
Jurrassic West: The Dinosaurs of the Morrison Formation and Their World by John Foster

Dec
09
2013

Charlie Darwin: The schoolbook victory in Texas obviously makes him feel like Charlie Sheen.
Charlie Darwin: The schoolbook victory in Texas obviously makes him feel like Charlie Sheen.Courtesy National Portrait Gallery
Last month, on November 22nd, while many people in the country were observing the 50th anniversary of president John F. Kennedy's assassination by shots fired from the Texas School Book Depository, there was another significant event happening that day involving Texas schoolbooks. That same Friday, despite objections and obstructionist tactics by creationists, the Texas Board of Education approved several public school science textbooks that included full coverage of evolution and climate change. The vote came late in the day and although the creationist faction did manage to make the adoption of two biology books contingent on a committee ruling regarding some alleged "flaws" in the text, the Texas Freedom Network (TFN), a watchdog group instrumental in countering the irrational creationist attacks, expects the passage to stand.

“It’s hard to overstate the importance of today’s vote, which is a huge win for science education and public school students in Texas,” said Kathy Miller, TFN's president. “Four years ago this board passed controversial curriculum standards some members hoped would force textbooks to water down instruction on evolution and climate change. But that strategy has failed because publishers refused to lie to students and parents demanded that their children get a 21st-century education based on established, mainstream science.”

SOURCES
Dallas Morning News story
Evolution is True article

Dec
06
2013

Victim of mass extinction: Will current species suffer a similar fate due to current environmental trends?
Victim of mass extinction: Will current species suffer a similar fate due to current environmental trends?Courtesy Mark Ryan
A new and troubling paper from the Committee on Understanding and Monitoring Abrupt Climate Change and its Impacts predicts possible and somewhat grim outcomes for some of Earth's natural systems from climate change that could rival the extinction event of the non-avian dinosaurs at the end of the Cretaceous Period 65 million years ago.

The abrupt impact could be coming faster than previously expected and would negatively affect human and physical climate systems as well. The document warns that the abruptness of the changes could be unanticipated and could find us unprepared to deal with them

Records of past climate preserved in tree rings, ice cores, and ocean sediments show that the atmosphere contains higher levels of carbon dioxide than it has in a very long time. Carbon emissions from human activity continue to add to this rising concentration. Other activities including deforestation and resource extraction place additional environmental pressures on our climate and other natural systems.

At the end of the Cretaceous, all species of non-avian dinosaurs, along with the megafauna of flying and swimming reptiles were wiped off the face of the Earth. Many dinosaur species showed signs of decline even before the Chicxlub asteroid delivered the final kibosh on their existence.

Dr. James W.C. White, a professor of Geological Sciences and of Environmental Studies at the University of Colorado at Boulder chaired the committee which included more than a dozen earth scientists and ocean researchers from universities in both Canada and the United States, and from the National Academy of Science.

A prepublication copy of the entire 201-page paper is available to read without charge on the National Academies Press page. You can also download it for free although it was a little tricky getting it to my computer.

SOURCE
MinnPost story

Nov
21
2013

3D printed dinosaur bone
3D printed dinosaur boneCourtesy Radiological Society of North America
Using state-of-the-art medical scanning and printing technology, German paleontologists have been able to scan and reconstruct a dinosaur vertebrae that survived a World War II bombing raid that left hundreds of fossils unidentified. Dug out of a clay pit south of Halberstadt, Germany in the early 20th century, the fossil was jacketed in plaster (for protection during transportation from the field) and stored in the basement of the Museum für Naturkunde in Berlin along with numerous other fossils from Halberstadt in southern Germany and another dig site in Tanzania. When the Allies made a bombing raid over Berlin during WWII, a portion of the museum was hit and collapsed, leaving the poorly labeled fossils in one big messy pile of plaster jackets and rubble. Museum workers sorted the jacketed fossils from the rubble but which fossil came from which dig? The labeled plaster jackets gave no clue.

Plateosaurus mount: Early postcard of a Plateosaurus skeleton seen in a museum in Stuttgart, Germany.
Plateosaurus mount: Early postcard of a Plateosaurus skeleton seen in a museum in Stuttgart, Germany.Courtesy Mark Ryan
Modern technology came to the rescue from technicians from the Department of Radiology at Charité Campus Mitte in Berlin. One of the jacketed fossils was first scanned with a CT (computed tomography) scanner - similar to those used to scan and diagnose medical patients. Because the radiation absorption (attenuation) of the fossil differs from that of the surrounding matrix - the rocky material in which the fossil is encased - making it easy to outline and create a digital copy of the fossil. The resulting image was compared to field drawings from the two expeditions and identified as a vertebrae of a Triassic Period prosauropod known as a Plateosaurus. The dataset was entered into a computer, cleaned up a bit, and then fed into a 3D printer where - layer by plastic layer - an exact replica of the hidden and unprepared fossil was "printed" in 3-dimensions.

CT scanning and 3D printing of fossils has been in use for a while now but this is a first time paleontologists have been able to identify and copy a dinosaur bone still encased in a matrix wrapped in a plaster field jacket.

In the past, this couldn't have been done without first cutting open the field jacket and spending long hours of detailed lab preparation - i.e. removing all the matrix from around the fossil. Making copies of fossils usually entails creating molds using rubber or something similar, then filling the void with plaster or other casting materials. Now with 3D printing technology, exact (or scaled) duplicates of important fossils can be created and shared with scientists or schools for study and comparison. The dataset of the scan can serve the same purpose.

Both the cost and size of the technology have been reduced in recent years, making it both affordable and portable for many museums. The following videos show the processes in action. Desktop scanning of dinosaur bones and the printing a dinosaur skull with a simple desktop 3D printer.

SOURCES and LINKS
Story on Science Daily
Live Science story