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https://www.thunderbolts.info/forum/php ... start=1380
Are the planets growing?
That was the original question that was asked on the prior Forum. Here is a link to that thread.
https://www.thunderbolts.info/forum/php ... 184#p12406
I recommend that if you are new to the question, that you actually read the whole thread. Be aware that there are 93 pages in that older thread on Forum (v2.0).
- Believe it or not, most of your questions have already been answered there. Really.
As you read the old thread, you will find many broken links. If that happens, then access:
The Way Back Machine
Simply copy the broken link from the Forum page, and paste it into the Way Back Machine to see if it was ever archived. Find a valid copy of the missing web site and read the article.
- Learn how to use the Way Back Machine.
- The Way Back Machine is your friend.
To those people continuing with this thread and the question, have fun.
Reason: link to 2.0 added
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800,000 Years Ago, a Meteor Slammed Into Earth. Scientists Just Found the Crater.
This is the paper they mention.By Mindy Weisberger - Senior Writer 6 days ago
A fiery meteor slams into Earth's atmosphere.
An ancient impact scattered bits of glassy debris from Asia to Antarctica, but the resulting crater has long eluded detection.
About 790,000 years ago, a meteor slammed into Earth with such force that the explosion blanketed about 10% of the planet with shiny black lumps of rocky debris. Known as tektites, these glassy blobs of melted terrestrial rock were strewn from Indochina to eastern Antarctica and from the Indian Ocean to the western Pacific. For more than a century, scientists searched for evidence of the impact that created these pitted blobs.
But the crater's location eluded detection — until now.
Geochemical analysis and local gravity readings told researchers that the crater lay in southern Laos on the Bolaven Plateau; the ancient impact was concealed under a field of cooled volcanic lava spanning nearly 2,000 square miles (5,000 square kilometers), the scientists reported in a new study.
Related: Fallen Stars: A Gallery of Famous Meteorites
When a meteor hits Earth, terrestrial rocks at the impact site can liquefy from the intense heat and then cool into glassy tektites, according to the Jackson School Museum of Earth History at The University of Texas. Scientists can look at the abundance and locations of tektites to help locate an impact, even if the original crater is eroded or concealed, the study authors wrote.
In this case, there were plenty of tektites — so where was the crater?
The force of the impact is thought to have created a rim measuring more than 300 feet (100 meters) tall, according to the study. Tektites from the impact were at their biggest and most abundant in the eastern part of central Indochina, but because the tektites were so widespread, previous estimates of the crater's size ranged from 9 miles (15 km) in diameter to 186 miles (300 km), and the feature's precise position remained uncertain even though scientists spent decades searching.
For the new study, the researchers first investigated several promising eroded crater candidates in southern China, northern Cambodia and central Laos, but soon ruled out those spots. In all cases, the suspected crater-like features turned out to be much older and were instead identified as erosion in rocks dating to the Mesozoic era — about 252 million years ago to about 66 million years ago.
Was the crater buried? On Laos' Bolaven Plateau, the scientists found a site where fields of volcanic lava might have hidden signs of an older meteor impact. In a region that the researchers targeted as a likely spot for a crater, most of the lava flows were also in the right age range: between 51,000 and 780,000 years old.
In this geological map of the volcanic field's summit region, the dashed, yellow ellipse marks the buried crater perimeter for the best-fitting gravity model. The dashed, white circle marks the buried perimeter that best fits geological observations. (Image credit: Sieh et al./PNAS 2019)
The study authors peered below the lava's surface by taking gravity readings at more than 400 locations. Their resulting gravity map showed one area "of particular interest" with a gravitational anomaly, a subsurface zone less dense than the volcanic rock surrounding it. Their measurements hinted at an elliptical, "elongated crater" about 300 feet (100 m) thick, about 8 miles (13 km) wide and 11 miles (17 km) long, according to the study.
Together, all of these clues suggested that "this thick pile of volcanic rocks does indeed bury the site of the impact," the scientists wrote.
The findings were published online Dec. 30 in the journal Proceedings of the National Academy of Sciences.
Australasian impact crater buried under the Bolaven volcanic field, Southern Laos
https://www.pnas.org/content/early/2019 ... 1904368116
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Time-lapse of lightning storm swirling round Philippine volcano
Rare volcano lightning seen as Taal Volcano in Philippines erupts
Volcanic Lightning - WTF Weather
As has been said in the prior thread, lightning in the crust is what triggers earthquakes and volcanos.
- JP Michael
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All this points to dynamic electrical forces involved in the earth-sky discharge phenomena that are the cause behind volcanism.
Volcanic ash clouds often swirl in a thick, columnar helix as it rises into the sky. They flatten out into an anvil-type cloud when the charges can separate into a double layer. Mainstream does not acknowledge dynamic currents as the primary cause (with static as secondary). How sad!
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This is quite a long read if you follow along with some of the sites.
I've changed my mind after reading, reading, reading a LOT of material on
My go is like this. When this so called one land mass broke apart, in my thinking,
now we have to think on a scale of HUMUNGOUS proportions, when these land masses
moved (broke apart) the collisions were something beyond imagination.
Then when they came to their present positions they set off one of the greatest volcanic
eruptions known of this planet. Thousands of these worldwide, most of them in the ring of fire,
erupted at the same time. Now, just try to imagine the smoke and gas that belched out
of the earth and into the atmosphere and rock also. Some of these, super volcanoes, maybe
ten to fifteen of these at least maybe more out of thousands of volcanoes around the world.
This happening would have been very bad, to be anywhere upon this planet at that time.
There are not any Bolide or Meteorite holes upon this planet. All of these holes are volcanic
in origin, either normal or super volcanoes.
I would also say that the great mountains were formed when these continents collided.
Subduction is a no no as they collide head on.
To the original post, possibly. There could be enough electrons emitted from the Sun to
have an impact on making matter with in this planet.
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I sent him the links again and found a video using an orange peel to demonstrate. This is similar to my example on the old forum with grapefruit/orange/tangerine continents with deep cantaloupe oceans.
Growing Earth Topology (Expanding Earth Theory)
I like his example, but mine is more fruitful. GET it, because I use more than just an orange peel. HA!
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As an alternative not altogether contradictory explanation, If the planet grew it implies some expansion caused by chemical reactions. I'm suggesting these took place quite deep and as they reacted and became lighter they rose up through a more or less liquid mantle, as they did they rotated due to the difference in rotational energy at say 5,000 km depth and the surface. The chemical reaction created charge+/-, and around the periphery there were counter rotating vortices, this would explain the gravitational anomoly and the volcanic activity. http://www-app2.gfz-potsdam.de/pb1/medi ... /eg21t.png
From http://www-app2.gfz-potsdam.de/pb1/op/g ... ce01s.html
I'm thinking the higher density anomolies are where metallic ore bodies rose from the depths, any geologists here?
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https://phys.org/news/2020-02-ancient-b ... heets.html
This is the paper they mention.by Peter Reuell, Harvard University
Study uses long-ago record of Bering Strait flooding to understand how ice sheets responded to climate change
Tamara Pico is the author of a new study which offers more precise dating for the flooding in the Bering Strait that occurred more than 11,000 years ago. Credit: Jon Chase/Harvard Staff Photographer
The debate has raged in the world of paleo-climate research for years: When did the land bridge that once connected Asia and North America flood?
Some researchers say the presence of Pacific species in the Arctic makes the case for some 13,000 years ago. Others, however, point to sediment cores collected from the area as evidence that the flooding occurred later, about 11,500 years ago.
For Tamara Pico, the issue is not which date is right, but how both—taken together—paint a fuller picture of how sea levels changed in the strait over more than 1,500 years.
Based on that picture, Pico, Ph.D. '19, was able to deduce how the ice sheets that covered North America responded to the warming climate, and how their melting might have contributed to climate changes. The study is described in a Feb. 26 paper in Science Advances.
"If we can understand sea-level change in the region around the ice sheet, we can infer the past history of the ice sheet," said Pico, who worked in the lab of Jerry Mitrovica, Frank B. Baird Jr. Professor of Science, as a graduate student and is now a National Science Foundation postdoctoral scholar at Caltech. "For me, the central question of this study is about understanding when and how much ice melted [during the deglaciation], because if you don't know how much ice volume melted, then you don't know how ice sheets are responding to a changing climate, and that's really the fundamental question."
Melting ice sheets, however, may only be the tip of the iceberg (pun intended). A better understanding of Bering Strait flooding may offer fresh insights into the sea-level differences.
"Nobody really thinks about using the record of the connection between two oceans as a sea-level record," Pico said. "But the observations suggest there is a connection early and a connection late. If we trust both of those data sets, then that means there was either a sea level fall or a standstill over that time, and in order to explain that, you need a melting ice sheet nearby."
But how can a melting ice sheet lead to sea level falling? The answer, Pico said, is gravity.
The ice sheets that once covered North America were so massive—some were taller than 9,800 feet, or nearly two miles—that they actually perturbed the planet's gravitational field, attracting ocean water. As they melted and that effect waned, Pico said, local sea levels would drop.
Elsewhere in the world, though, the story at the time was very different.
"Globally, we know sea level during this period is rising at something like 10 meters per 1,000 years, so it's not as if global sea level had stopped rising," Pico said. "It rises quite a bit over that time, so for local sea level to have stayed the same you need this effect.
"This time period, from 13,000 years ago to 11,500 years ago, also marks the Younger Dryas cooling period," Pico said. "Over the last deglaciation... for the most part, temperatures were rising, but based on the Greenland ice-core record, temperatures actually seem to drop over this period, and that's always been an enigma."
Since the 1980s, the prevailing explanation for the cooling has been that a massive influx of cold, fresh water might have led to a change in ocean circulation patterns that weakened the oceans' ability to act as a global heat sink.
The work of Pico and colleagues suggests that the melting North American ice sheets could have pumped a steady stream of fresh water into the Arctic—enough to sustain the Younger Dryas for nearly 2,000 years.
"According to the sea-level record in the Bering Strait, you would need to melt a lot of ice—the equivalent of between 10 and 15 meters of global sea-level rise—and this melting is happening over that entire time," she said. "So this might be able to explain why the Arctic cooled for that period. Rather than it being a lake that had an outburst flood, it was just the melting ice sheet."
Despite the sea-level data from the Bering Strait, that hypothesis hasn't been universally accepted, Pico said, in part because the study places the melting of the "saddle"—the region where the two North American ice sheets meet—at a time significantly later than many believe it was.
"Most people assume that happened earlier because, even though sea level was rising quickly around the world, there was a period—called meltwater pulse 1A—when it rose especially fast," she said. "In that period, sea level rose by 15 to 20 meters in under 300 years. That would require a huge amount of ice melt, and many people have assumed the saddle melted during this time.
"But that assumed history doesn't fit the Bering Strait sea-level record," she continued. "When we use that flooding history as a sea-level record, it's not consistent with what everyone had assumed before."
Huge stores of Arctic sea ice likely contributed to past climate cooling
More information: T. Pico et al. Sea level fingerprinting of the Bering Strait flooding history detects the source of the Younger Dryas climate event, Science Advances (2020). DOI: 10.1126/sciadv.aay2935
Provided by Harvard University
This story is published courtesy of the Harvard Gazette, Harvard University's official newspaper. For additional university news, visit Harvard.edu.
Sea level fingerprinting of the Bering Strait flooding history detects the source of the Younger Dryas climate event
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Researchers find evidence of a cosmic impact that caused destruction of one of the world's earliest human settlements
https://phys.org/news/2020-03-evidence- ... world.html
Here's the paper they referenced.by Sonia Fernandez, University of California - Santa Barbara
Researchers find evidence of a cosmic impact that caused destruction of one of the world’s earliest human settlements
Location of Abu Hureyra (adapted from Moore et al.. (a) Map of the Middle East, showing Abu Hureyra location (AH) in Syria. (b) Map of the Abu Hureyra tell, showing locations of excavation trenches labeled A-G near a back channel of Euphrates River that is now abandoned. Sediment samples from Trenches D, E, and G (blue rectangles) contain abundance peaks in YDB proxies, including spherules, nanodiamonds, meltglass, and platinum. Credit: Scientific Reports (2020). DOI: 10.1038/s41598-020-60867-w
Before the Taqba Dam impounded the Euphrates River in northern Syria in the 1970s, an archaeological site named Abu Hureyra bore witness to the moment ancient nomadic people first settled down and started cultivating crops. A large mound marks the settlement, which now lies under Lake Assad.
But before the lake formed, archaeologists were able to carefully extract and describe much material, including parts of houses, food and tools—an abundance of evidence that allowed them to identify the transition to agriculture nearly 12,800 years ago. It was one of the most significant events in our Earth's cultural and environmental history.
Abu Hureyra, it turns out, has another story to tell. Found among the cereals and grains and splashed on early building material and animal bones was meltglass, some features of which suggest it was formed at extremely high temperatures—far higher than what humans could achieve at the time—or that could be attributed to fire, lighting or volcanism.
"To help with perspective, such high temperatures would completely melt an automobile in less than a minute," said James Kennett, a UC Santa Barbara emeritus professor of geology. Such intensity, he added, could only have resulted from an extremely violent, high-energy, high-velocity phenomenon, something on the order of a cosmic impact.
Based on materials collected before the site was flooded, Kennett and his colleagues contend Abu Hureyra is the first site to document the direct effects of a fragmented comet on a human settlement. These fragments are all part of the same comet that likely slammed into Earth and exploded in the atmosphere at the end of the Pleistocene epoch, according to Kennett. This impact contributed to the extinction of most large animals, including mammoths, and American horses and camels; the disappearance of the North American Clovis culture; and to the abrupt onset of the end-glacial Younger Dryas cooling episode.
The team's findings are highlighted in a paper published in the Nature journal Scientific Reports.
"Our new discoveries represent much more powerful evidence for very high temperatures that could only be associated with a cosmic impact," said Kennett, who with his colleagues first reported evidence of such an event in the region in 2012.
Abu Hureyra lies at the easternmost sector of what is known as the Younger Dryas Boundary (YDB) strewnfield, which encompasses about 30 other sites in the Americas, Europe and parts of the Middle East. These sites hold evidence of massive burning, including a widespread carbon-rich "black mat" layer that contains millions of nanodiamonds, high concentrations of platinum and tiny metallic spherules formed at very high temperatures. The YDB impact hypothesis has gained more traction in recent years because of many new discoveries, including a very young impact crater beneath the Hiawatha Glacier of the Greenland ice sheet, and high-temperature meltglass and other similar evidence at an archaeological site in Pilauco, located in southern Chile.
"The Abu Hureyra village would have been abruptly destroyed," Kennett said. Unlike the evidence from Pilauco, which was limited to human butchering of large animals up to but not younger than the YDB impact burn layer, Abu Hureyra shows direct evidence of the disaster on this early human settlement. An impact or an airburst must have occurred sufficiently close to send massive heat and molten glass over the entire early village, Kennett noted.
The glass was analyzed for geochemical composition, shape, structure, formation temperature, magnetic characteristics and water content. Results from the analysis showed that it formed at very high temperatures and included minerals rich in chromium, iron, nickel, sulfides, titanium and even platinum- and iridium-rich melted iron—all of which formed in temperatures higher than 2200 degrees Celsius.
"The critical materials are extremely rare under normal temperatures, but are commonly found during impact events," Kennett said. According to the study, the meltglass was formed "from the nearly instantaneous melting and vaporization of regional biomass, soils and floodplain deposits, followed by instantaneous cooling." Additionally, because the materials found are consistent with those found in the YDB layers at the other sites across the world, it's likely that they resulted from a fragmented comet, as opposed to impacts caused by individual comets or asteroids.
"A single major asteroid impact would not have caused such widely scattered materials like those discovered at Abu Hureyra," Kennett said. "The largest cometary debris clusters are proposed to be capable of causing thousands of airbursts within a span of minutes across one entire hemisphere of Earth. The YDB hypothesis proposed this mechanism to account for the widely dispersed coeval materials across more than 14,000 kilometers of the Northern and Southern Hemispheres. Our Abu Hureyra discoveries strongly support a major impact event from such a fragmented comet."
Geologic evidence supports theory that major cosmic impact event occurred approximately 12,800 years ago
More information: Andrew M. T. Moore et al. Evidence of Cosmic Impact at Abu Hureyra, Syria at the Younger Dryas Onset (~12.8 ka): High-temperature melting at >2200 °C, Scientific Reports (2020). DOI: 10.1038/s41598-020-60867-w
Provided by University of California - Santa Barbara
Evidence of Cosmic Impact at Abu Hureyra, Syria at the Younger Dryas Onset (~12.8 ka): High-temperature melting at >2200 °C
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Antarctica Was a Lush Rainforest 90M Years Ago, Scientists Discover
https://www.vice.com/en_us/article/n7jy ... s-discover
Look at the video and see that Antarctica was higher up. It was Africa that was at the South Pole.An ancient sediment core revealed a shocking discovery: pollen and spores, indicating a long-lost rainforest that was shrouded in perpetual darkness for months at a time. By Becky Ferreira Apr 1 2020, 9:01amShareTweetSnap
Modern rainforest. Image: Samuel Butler/ EyeEm
Antarctica is the most remote and barren continent on Earth; a land where only the hardiest creatures can survive the punishing year-round conditions. But dial the clock back by 90 million years to the age of dinosaurs, and this icy landscape transforms into a lush temperate rainforest that somehow braved months of perpetual darkness.
The story of this ancient Antarctic rainforest is written in sediment buried 25 meters under the seafloor off Pine Island Glacier, according to a study published on Wednesday in Nature. The fossils preserved in an ultra-rare core represent the first glimpse of Cretaceous ecosystems at latitudes this far south, just 500 miles from the South Pole.
“It is definitely the southernmost Cretaceous evidence ever recovered on the planet,” said lead author Johann Klages, a geologist at the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, in a call. “We were the first ones to ever drill there in that environment.”
Klages and his colleagues obtained the core during a 2017 expedition of the research vessel Polarstern, but the extraction process was not easy. The specialized drilling machine used to penetrate the seafloor required several days to pull out each new core, and all it seemed to be reaching was quartzitic sandstone layers bereft of fossils.
The MeBo seabed drilling system on RV Polarstern. Image: JP Klages, AWI
Meanwhile, ice sheets from the nearby island began advancing toward the sample site, threatening to slice the cord between the drill and the vessel. Before evacuating the area to prevent the loss of expensive equipment, Klages and his colleagues decided to take one last three-meter core.
Unlike the light-colored sandstone, this core was dark, suggesting it was rich in organic materials. “We immediately saw that something special was going on,” recalled Klages. “We saw these amazing, pristine, complete, dense networks of fossil roots in the core connected down to the core base.”
“If you go to the forest in front of your house, or somewhere, and you drill a hole, you would get something very similar,” he said. “It was full of pollen and spores and really diverse assemblages.”
Over the past three years, the team has meticulously examined the core and unraveled incredible new details about the rainforest that once blanketed Antarctica. The pristine condition of these plant fossils demonstrates that this was a swampy ecosystem of conifer trees that may have looked like the rainforests of modern New Zealand.
Based on comparisons with similar Cretaceous biomes found much farther north, dinosaurs may well have roamed through this biodiverse Antarctic landscape. “It’s very likely that there were insects and dinosaurs and all of that there too,” Klages said, “but we can’t say for sure because we did not find anything like that. We only can say a lot of stuff about the paleobotany that we found in the core.”
Remarkably, these forests were located at a southern latitude of 82°, which means they would have been plunged into total darkness for about four months of each year. Modern rainforests rely on perpetual sunlight to survive, but this bygone ecosystem had to switch to another source of energy for the long, black winter.
Artist concept of ancient rainforest. Image: Alfred-Wegener-Institut/J. McKay
That fuel may have been supplied by extraordinarily high levels of atmospheric carbon dioxide, which could have staved the forests over until the return of the Sun. In fact, the discovery of this rainforest strongly suggests that CO2 levels in this era were higher than previously assumed, perhaps reaching 1,680 parts per million (ppm). For reference, our current CO2 levels are just above 400 ppm, though they are rapidly rising due to human activity.
These high CO2 levels imply that Cretaceous Earth was warmer than expected, and that no ice cover existed at the South Pole. Klages and his colleagues estimate that the mean annual temperature in the rainforest was about 12°C, with summer temperatures averaging around 19°C.
“It really was that warm,” Klages said. “That amazed us, of course, but also the climate modelers because no one expected such extreme values very close to the South Pole."
"We are quite confident now in saying that there was no ice present, that Antarctica was completely vegetated, and that we had very high CO2 concentrations.”
The research offers a rare chance to imagine this strange Antarctic forestland, but it also contains lessons for our modern warming world. For instance, Klages and his colleagues modelled what would happen if the current version of Earth had the same CO2 levels, and found that our planet’s polar ice cover reflects too much sunlight to result in the same high global temperatures.
“The presence of an ice sheet makes a huge difference, even if you have very high CO2 concentrations,” Klages said. “That is really important for us to know, and to think about how we can better preserve ice sheets.”
“We need to look into these extreme climates that happened on the planet already, because they show us what a greenhouse climate looks like,” he concluded. “We are definitely in an interesting time because if we continue what we’re doing right now, then it could lead into something that we can’t control anymore.”
Expanding Earth and Pangaea Theory
- Their core sample is 90 million years old. There was no deep sea floor 90 million years ago.
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A chunk of Yellowstone the size of Chicago has been pulsing. Why?
An injection of magma under Norris Geyser Basin may be why the region is five inches higher today than it was 20 years ago.
https://www.nationalgeographic.com/scie ... n-pulsing/
March 19, 2020
In northwestern Wyoming, in the center of Yellowstone National Park, a bubbling caldera is the scar of a 640,000-year-old, gargantuan volcanic eruption. The 3,472-square-mile park encompassing the caldera is filled with geologic wonderlands of sprouting geysers and effervescing pools, all ultimately driven by magma and superheated fluids churning in the rock below the surface.
One of these areas, Norris Geyser Basin to the northwest of the caldera, contains more than 500 hydrothermal features. These tempestuous geysers and pools often change from day to day, but a much larger transformation has been taking place as well: For more than two decades, an area larger than Chicago centered near the basin has been inflating and deflating by several inches in erratic bursts. In a hyperactive volcanic region like Yellowstone, the exact causes of any specific movement are difficult to pin down. But a recent study in the Journal of Geophysical Research: Solid Earth may help explain why this pocket of land has been breathing in and out.
“In all likelihood, Norris has been a center of deformation for a very long time,” says Daniel Dzurisin, a research geologist at the U.S. Geological Survey’s Cascades Volcano Observatory and one of the co-authors of the new research.
Scientists used decades of satellite-based radar and GPS data of Norris Geyser Basin to model what may have occurred below its surface based on the changes above. In the late 1990s, a body of magma intruded beneath Norris, and fluids trapped within the magma bubbled out and made their way through the rocky labyrinth above them. As the fluids got stuck and pressure built up, the ground would rise, and when the fluids were able to escape elsewhere, the ground deflated. Today, magma-derived fluids could sit close to the surface, just a mile or so below the ground.
To be clear, the new research does not indicate that the supervolcano that created Yellowstone’s caldera—which last erupted 640,000 years ago—is any more likely to erupt now. Instead, these geologic movements may help explain why the park’s Steamboat Geyser, the world’s tallest active geyser, has been erupting at a record-breaking pace since March 2018. Researchers also speculate that the changes below Norris may mean a slightly increased chance of hydrothermal explosions taking place in the basin. (Get a peek inside Yellowstone's supervolcano.)
The geology of Yellowstone is complex and elusive, and investigations of the subsurface are particularly challenging. But researchers agree that the injection of a large body of magma and the fluids that escaped during the event are plausible explanations for the rising and falling ground.
“We’re only just beginning to understand just how dynamic [Norris Geyser Basin] is,” says Michael Poland, the scientist-in-charge at the U.S. Geological Survey’s Yellowstone Volcano Observatory who wasn’t involved in the new research.
The Notorious NGB
Norris Geyser Basin is Yellowstone’s oldest thermal area, with evidence of thermal features going back 115,000 years. It’s also the hottest, registering 459 degrees Fahrenheit a thousand feet or so beneath the surface.
The region’s Steamboat Geyser exemplifies how drastically and unexpectedly this scalding patch of Yellowstone can change. The 400-foot-tall geyser has historically erupted infrequently, with gaps between major eruptions lasting between four days and half a century. But since March 2018, Steamboat has erupted as frequently as once a week. Its 32 eruptions in 2018 set a record that was broken the next year, when the geyser erupted 48 times.
“The blinking thing went nuts!” says Helen Robinson, a geothermal expert at Glasgow University who was not involved with the new work.
Although the hyperactivity of this mercurial geyser has captured the public’s attention, scientists are more interested in the dramatic quavering of the basin itself. Between 1996 and 2004, an 18-mile-long area rose 4.7 inches, only to sink back 2.8 inches between 2005 to 2013. Then the region suddenly shot up again at a rate of 5.9 inches a year between late 2013 and early 2014, the highest pace of uplift ever observed within Yellowstone National Park.
In March 2014, a magnitude 4.9 earthquake rocked Norris Geyser Basin, bring the seemingly unstoppable uplift to a sudden halt. The ground gradually fluctuated between sinking and rising until early 2019, when it began to subside—but the basin is now around five inches higher than it was in 2000.
Radar and GPS data from satellites were used to track the deformation of Norris Geyser Basin, and geologists suspect that the upheaval began when magma rose just shy of nine miles beneath the surface between 1996 and 2001. The basin, just outside the northwestern rim of the supervolcano’s youngest caldera, sits on a line of faults and vents known as the Norris-Mammoth corridor.
“Two weak zones intersecting one another—that would be a place where magma might find an easier way to intrude,” Dzurisin says.
The magmatic intrusion was responsible for the 1996 to 2004 uplift event, and as the magma cooled, fluids dissolved within it were able to bubble out. This process lowered the internal pressure of the magma body, causing it to deflate like a leaky balloon, which likely caused the ground to lower again between 2005 until 2013.
The escaping fluid has become repeatedly trapped in pockets beneath layers of rock, causing the ground to rise in fits and starts ever since. This cycle of magmatism and hydrothermal activity has proven elusive for scientists to identify and chronicle. The new model is “a reasonable hypothesis, but it’s by no means certain,” Poland says. Perhaps sources of fluids other than the body of magma, such as heavy snows in recent years, collect in pockets and sporadically escape elsewhere as the landscape inhales and exhales, Robinson says.
Geysers and possible explosions on the surface
The team suspects that magma-derived fluids are now sitting just beneath the surface of Norris Geyser Basin. Hydrothermal explosion craters dating back thousands of years can be found all over the region, caused by geologic pressure cookers of confined, scorching water that violently depressurize and flash-boil into steam if the rock cracks, an event that is all-but-impossible to forecast.
A new blast could potentially take place in Norris Geyser Basin at any time, though major explosions are rare. If fluids have pooled close to the basin’s surface, hydrothermal explosions may be slightly more likely to occur. But the rocky plumbing networks are remarkably complex, Dzurisin says, with small, undetectable changes constantly increasing and decreasing the chances of a blast. The possibility of more explosions remains highly speculative, so the team does not recommend closing off the region to visitors.
The team also wonders if the accumulation of magmatic fluids could be connected to Steamboat’s recent record-breaking number of eruptions. The geyser had similar upticks in activity in the 1960s and early 1980s, perhaps also linked to basin breathing cycles.
But if this really is the case, why is this particular geyser putting on a show when several others remain quiet? “Why not Echinus, which is right next to Steamboat?” wonders Poland.
The link between Steamboat’s hyperactivity and the magma intrusion is circumstantial at best, Dzurisin says, but “the timing does line up.” In the future, he and his colleagues hope to study the fluids that bubble up through the surface to see if they have the chemical fingerprints of a magmatic origin.
Still, the fact that researchers were able to craft a narrative that might explain these dramatic changes is a testament to decades of accumulated data and modern scientific techniques. Twenty years ago, Dzurisin says, such a feat would have been “nearly impossible.”
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A good way to view the downloaded jpg is in a browser. It lets you move around the map quickly. You point at an area that you want to see in detail, move around a bit, then come out to see the whole image and select a new region.
Scientists Just Released The Most Complete Geologic Moon Map Yet, And It's Glorious
https://www.sciencealert.com/the-most-c ... r-missions
RELEASE OF THE DIGITAL UNIFIED GLOBAL GEOLOGIC MAP OF THE MOON - 2760.pdfmain article image
Those light and dark spots you can see when you gaze at the Moon from afar are only hints of the rich geological diversity that can be found on our nearest celestial neighbour, and scientists have put together the most detailed map of the Moon's rock composition yet.
Not only is the finished map incredible to look at, it'll also act as a blueprint for future missions to the Moon, guiding astronauts towards suitable landing spots and areas that are worthy of further scientific investigation.
The fascinating map of lunar geology has been put together by a team from NASA, the Lunar Planetary Institute in Texas, and the Astrogeology Science Center in Arizona, run by the US Geological Survey (USGS).
moon map 2(USGS)
"People have always been fascinated by the moon and when we might return," says Jim Reilly, former NASA astronaut and the current director of USGS. "So, it's wonderful to see USGS create a resource that can help NASA with their planning for future missions."
At a 1:5,000,000 scale, the map was compiled from data collected from six Apollo-era maps, as well as more recent satellite imagery. Geographical software was used to stitch all the parts into one coherent whole.
moon map geologic fragmentA sample of the map. (USGS)
As well as combining several old and new datasets, the scientists behind the project also standardised the rock names, descriptions and ages – details that had previously varied from map to map.
Topological information has been added in, too: the locations of craters, crests, fissures, ridges, faults, and all the other irregularities in the Moon's surface. There's more to come, with experts planning even more detailed geological maps in the future.
"It was a huge effort for our team to complete this new map and make it seamless," says Justin Hagerty, Astrogeology Director at USGS. "Much of the historical mapping was performed by various groups and at regional scales."
"Slightly different methods were used, so that maps of the same feature that had been mapped by different groups would not match."
The Moon does have a crust, a mantle and a core, but it doesn't have tectonic plates like Earth does. One of the ways in which a better understanding of the Moon's geology can be useful is in charting out its 4.5-billion-year history: how it came into being, the way it's evolved since, and everything that's collided with it along the way.
Studies of our satellite have also been helped by the rock samples that have been collected on lunar missions.
As for future missions, they will no doubt be consulting this new map. NASA is currently planning to send humans to the Moon again in 2024.
"This map is a culmination of a decades-long project," says geologist Corey Fortezzo, from USGS. "It provides vital information for new scientific studies by connecting the exploration of specific sites on the moon with the rest of the lunar surface."
You can read a paper on the map here and view the map itself online here.
The map is here, with options to download a jpg of the full map.
Unified Geologic Map of the Moon, 1:5M, 2020
https://astrogeology.usgs.gov/search/ma ... e_Moon_GIS
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Hubble identified about 30 fragments on April 20, and 25 pieces on April 23. They are all enveloped in a sunlight-swept tail of cometary dust. "Their appearance changes substantially between the two days, so much so that it's quite difficult to connect the dots," said David Jewitt, professor of planetary science and astronomy at UCLA, Los Angeles, and leader of one of two teams that photographed the doomed comet with Hubble. "I don't know whether this is because the individual pieces are flashing on and off as they reflect sunlight, acting like twinkling lights on a Christmas tree, or because different fragments appear on different days." ...
The results are evidence that comet fragmentation is actually fairly common, say researchers. It might even be the dominant mechanism by which the solid, icy nuclei of comets die. Because this happens quickly and unpredictably, astronomers remain largely uncertain about the cause of fragmentation. ...
https://www.nasa.gov/feature/goddard/20 ... zen-pieces
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