<![CDATA[Scivillage.com Casual Discussion Science Forum - Geophysics, Geology & Oceanography]]> https://www.scivillage.com/ Sun, 04 Oct 2026 02:22:18 +0000 MyBB <![CDATA[Simulating cosmic crashes to test icy moons' ability to sustain life (exo-geology)]]> https://www.scivillage.com/thread-21381.html Sat, 19 Sep 2026 18:14:21 +0000 C C]]> https://www.scivillage.com/thread-21381.html Scientists simulate cosmic crashes to test whether icy moons gain or lose their ability to sustain life
https://www.eurekalert.org/news-releases/1144588

EXCERPT: Scientists suspect some of today’s moons are reassembled remnants of earlier generations of moons, shattering and reforming from space debris. One question arises: Do these collisions also destroy a moon’s ocean and with it, any chance for life?

A University of Maryland-led study published on August 21, 2026, in the journal Nature Astronomy offers an answer. After simulating violent collisions on frozen moons, researchers found that even the biggest crashes don’t fundamentally change whether these icy worlds can hold an ocean.

“The big question we asked was whether these destructions help moons have oceans afterward or whether they delete the ocean and reset the moon into a cold, dead world,” explained the study’s lead author Marc Neveu, an astronomy associate research scientist at UMD. “What we found was that those big collisions don't really matter as far as oceans are concerned. If there was an ocean before, there's likely to be an ocean after and vice versa.”

The finding surprised Neveu and his co-authors at the Southwest Research Institute in Colorado and the Weizmann Institute of Science in Israel... (MORE - missing details, no ads)]]> Scientists simulate cosmic crashes to test whether icy moons gain or lose their ability to sustain life
https://www.eurekalert.org/news-releases/1144588

EXCERPT: Scientists suspect some of today’s moons are reassembled remnants of earlier generations of moons, shattering and reforming from space debris. One question arises: Do these collisions also destroy a moon’s ocean and with it, any chance for life?

A University of Maryland-led study published on August 21, 2026, in the journal Nature Astronomy offers an answer. After simulating violent collisions on frozen moons, researchers found that even the biggest crashes don’t fundamentally change whether these icy worlds can hold an ocean.

“The big question we asked was whether these destructions help moons have oceans afterward or whether they delete the ocean and reset the moon into a cold, dead world,” explained the study’s lead author Marc Neveu, an astronomy associate research scientist at UMD. “What we found was that those big collisions don't really matter as far as oceans are concerned. If there was an ocean before, there's likely to be an ocean after and vice versa.”

The finding surprised Neveu and his co-authors at the Southwest Research Institute in Colorado and the Weizmann Institute of Science in Israel... (MORE - missing details, no ads)]]> <![CDATA[Squid are taking over the ocean – And not for the reason you might think]]> https://www.scivillage.com/thread-21279.html Mon, 07 Sep 2026 17:19:01 +0000 C C]]> https://www.scivillage.com/thread-21279.html https://www.sciencealert.com/squid-are-t...ight-think

INTRO: We've made some drastic changes to ocean ecosystems in the past century. One of the stranger patterns to appear in this is a global proliferation of tentacled creatures known as cephalopods, and in particular, squids.

Decades of ocean warming and overfishing may be correlated with an increase in the sheer volume of squid. But researchers are warning we can't necessarily expect them to fill the gaps left by heat-shocked, depleted, and displaced fisheries.

In 2016, a team led by researchers at the University of Adelaide found cephalopod populations had increased across six decades' worth of data. Their study showed this increase occurred regardless of the presence of a fishery, "suggesting that trends are not solely due to factors associated with developing fisheries".

They proposed the squid boom could be because the predators that would usually keep squid numbers down have been overfished. But because the trend occurred even outside of fished areas, they also suggested that the increased sea temperatures that have come with climate change could be playing a role.

These are interesting ideas, but as marine biologist Rémy Denéchère and team write in a preprint, "the proposed explanations for the historical increase in squid abundance are speculative, and the underlying mechanisms remain unclear".

The researchers found that warmer seas might not necessarily mean squid proliferate as a direct result of overfishing or climate change.

They used computer models of ecosystems to see how squid (and other fish in the environment) would theoretically be affected by a drop in predators and by changes in water temperature.When top predators were overfished, squid abundance increased – but that didn't compensate for the significant decline in predatory fish biomass.

Squid did not simply fill the void left by their predators... (MORE - details)]]> https://www.sciencealert.com/squid-are-t...ight-think

INTRO: We've made some drastic changes to ocean ecosystems in the past century. One of the stranger patterns to appear in this is a global proliferation of tentacled creatures known as cephalopods, and in particular, squids.

Decades of ocean warming and overfishing may be correlated with an increase in the sheer volume of squid. But researchers are warning we can't necessarily expect them to fill the gaps left by heat-shocked, depleted, and displaced fisheries.

In 2016, a team led by researchers at the University of Adelaide found cephalopod populations had increased across six decades' worth of data. Their study showed this increase occurred regardless of the presence of a fishery, "suggesting that trends are not solely due to factors associated with developing fisheries".

They proposed the squid boom could be because the predators that would usually keep squid numbers down have been overfished. But because the trend occurred even outside of fished areas, they also suggested that the increased sea temperatures that have come with climate change could be playing a role.

These are interesting ideas, but as marine biologist Rémy Denéchère and team write in a preprint, "the proposed explanations for the historical increase in squid abundance are speculative, and the underlying mechanisms remain unclear".

The researchers found that warmer seas might not necessarily mean squid proliferate as a direct result of overfishing or climate change.

They used computer models of ecosystems to see how squid (and other fish in the environment) would theoretically be affected by a drop in predators and by changes in water temperature.When top predators were overfished, squid abundance increased – but that didn't compensate for the significant decline in predatory fish biomass.

Squid did not simply fill the void left by their predators... (MORE - details)]]> <![CDATA[A mysterious, wandering island has emerged in a Canadian lake]]> https://www.scivillage.com/thread-21237.html Wed, 02 Sep 2026 16:14:18 +0000 C C]]> https://www.scivillage.com/thread-21237.html The lake surface area is 1,761 kilometers or 680 square miles. Arguably the size of an average or modest county in the US. Though it's elongated.
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A mysterious, wandering island has emerged in a Canadian lake
https://www.sciencealert.com/a-mysteriou...adian-lake

EXCERPTS: A floating island loaded with green, healthy-looking trees has been spotted drifting around Williston Lake in Canada, and we've never seen anything like it. Rocky Avery, a British Columbia local resident and boater, shared a video of the strange floating 'island' on social media.

Technically, it's more like a raft than an island, with trees and other plants growing on something seemingly buoyant, like driftwood. The reservoir is managed by BC Hydro, a power company that harnesses electricity from the dam.

Since it's 2026 and the internet is swamped in AI-generated videos, BC Hydro spokesperson Bob Gammer was rightly suspicious of the reports at first.

[...] On July 21st, 2026, a tiny green island-like blob was indeed visible from the European Space Agency's Sentinel-2 satellite. ... On that day, the 'island' was about 100 kilometers (62 miles) west of the W.A.C. Bennett Dam. It doesn't appear to be there in the days before, and it's unclear where it went in the days after.

On August 31, Avery announced on his Facebook page that the island had been found again – this time in the Ospika River, which flows into Williston Lake.[...] Gammer suggested in his CBC interview that the floating island may have formed on the shore across several years, breaking off and floating freely when the water levels reached those record peaks.

[...] At present, the 'island' doesn't seem to be posing any problems to the dam, though boaters and fishers might do well to be wary of these sorts of unmarked hazards... (MORE - missing detail

Learning that the island moves ... https://youtu.be/k-X3Doh4i6M

https://www.youtube-nocookie.com/embed/k-X3Doh4i6M]]> The lake surface area is 1,761 kilometers or 680 square miles. Arguably the size of an average or modest county in the US. Though it's elongated.
- - - - - - - - - - -

A mysterious, wandering island has emerged in a Canadian lake
https://www.sciencealert.com/a-mysteriou...adian-lake

EXCERPTS: A floating island loaded with green, healthy-looking trees has been spotted drifting around Williston Lake in Canada, and we've never seen anything like it. Rocky Avery, a British Columbia local resident and boater, shared a video of the strange floating 'island' on social media.

Technically, it's more like a raft than an island, with trees and other plants growing on something seemingly buoyant, like driftwood. The reservoir is managed by BC Hydro, a power company that harnesses electricity from the dam.

Since it's 2026 and the internet is swamped in AI-generated videos, BC Hydro spokesperson Bob Gammer was rightly suspicious of the reports at first.

[...] On July 21st, 2026, a tiny green island-like blob was indeed visible from the European Space Agency's Sentinel-2 satellite. ... On that day, the 'island' was about 100 kilometers (62 miles) west of the W.A.C. Bennett Dam. It doesn't appear to be there in the days before, and it's unclear where it went in the days after.

On August 31, Avery announced on his Facebook page that the island had been found again – this time in the Ospika River, which flows into Williston Lake.[...] Gammer suggested in his CBC interview that the floating island may have formed on the shore across several years, breaking off and floating freely when the water levels reached those record peaks.

[...] At present, the 'island' doesn't seem to be posing any problems to the dam, though boaters and fishers might do well to be wary of these sorts of unmarked hazards... (MORE - missing detail

Learning that the island moves ... https://youtu.be/k-X3Doh4i6M

https://www.youtube-nocookie.com/embed/k-X3Doh4i6M]]> <![CDATA[Mount Everest glaciers melting: Human waste is the main catalyst]]> https://www.scivillage.com/thread-21222.html Mon, 31 Aug 2026 15:13:14 +0000 C C]]> https://www.scivillage.com/thread-21222.html https://timesofindia.indiatimes.com/etim...647191.cms

Devastated in seconds, Nepal's flash flood has again raised concerns as experts believe that Mount Everest base camp is also leading glacier melt around the base camp region, and human waste is one of the major causes of this sudden change!

A study published in Regional Environmental Change shines a light on the growing environmental stress placed on Mount Everest's Khumbu Glacier. Led by an international team including a senior surveying official from Nepal's Ministry of Land Management, the research reveals that basic human presence at Base Camp radiates enough thermal energy to melt nearly 2,500 tons of ice and snow annually.

Every peak spring climbing season, thousands of mountaineers, local guides, and support staff set up shop on the Nepalese side of Everest. Base Camp effectively turns into a crowded pop-up city running around 1,600 tents. To keep client operations comfortable, camps offer luxury additions like cafes, high-speed Wi Fi, hot showers, and heated floorboards. Running a camp of this scale over a 50-day window takes a massive supply of fuel.

During the spring of 2023, operators burned through 824 cylinders of LPG, 18,935 liters of kerosene, and 5,130 liters of gasoline just to keep heat, cooking, and generators running.

The thermal energy transferred into the environment from burning fuel, combined with the heat from human waste, reaches roughly 849,174 megajoules during a single climbing season. That volume of energy is enough to melt 2,492 tons of glacier ice and snow. Converted into liquid, 2,500 tons of melted ice holds enough water to fill an international-standard Olympic swimming pool.

An unexpected driver of this localized melting comes from human urine. To combat severe high-altitude dehydration, individuals at base camp consume high volumes of liquids, resulting in over 6,000 liters of urine discharged every day. Solid waste is collected in storage tanks and hauled down the mountain, but liquid waste is generally discarded directly onto the surrounding glacier. Researchers calculated that the heat transferred from urine alone is responsible for melting roughly 154 tons of ice each season.

The study’s figures remain conservative. The researchers noted that their calculations excluded heat generated by helicopter flights, direct body heat from thousands of climbers, and transport animals like yaks. Including these variables would make the total human impact even higher. While global climate change remains the main cause of retreating glaciers across the Himalayas, researchers warn that concentrating dense human activity and artificial heat sources on an already fragile glacier is unsustainable over the long term.]]> https://timesofindia.indiatimes.com/etim...647191.cms

Devastated in seconds, Nepal's flash flood has again raised concerns as experts believe that Mount Everest base camp is also leading glacier melt around the base camp region, and human waste is one of the major causes of this sudden change!

A study published in Regional Environmental Change shines a light on the growing environmental stress placed on Mount Everest's Khumbu Glacier. Led by an international team including a senior surveying official from Nepal's Ministry of Land Management, the research reveals that basic human presence at Base Camp radiates enough thermal energy to melt nearly 2,500 tons of ice and snow annually.

Every peak spring climbing season, thousands of mountaineers, local guides, and support staff set up shop on the Nepalese side of Everest. Base Camp effectively turns into a crowded pop-up city running around 1,600 tents. To keep client operations comfortable, camps offer luxury additions like cafes, high-speed Wi Fi, hot showers, and heated floorboards. Running a camp of this scale over a 50-day window takes a massive supply of fuel.

During the spring of 2023, operators burned through 824 cylinders of LPG, 18,935 liters of kerosene, and 5,130 liters of gasoline just to keep heat, cooking, and generators running.

The thermal energy transferred into the environment from burning fuel, combined with the heat from human waste, reaches roughly 849,174 megajoules during a single climbing season. That volume of energy is enough to melt 2,492 tons of glacier ice and snow. Converted into liquid, 2,500 tons of melted ice holds enough water to fill an international-standard Olympic swimming pool.

An unexpected driver of this localized melting comes from human urine. To combat severe high-altitude dehydration, individuals at base camp consume high volumes of liquids, resulting in over 6,000 liters of urine discharged every day. Solid waste is collected in storage tanks and hauled down the mountain, but liquid waste is generally discarded directly onto the surrounding glacier. Researchers calculated that the heat transferred from urine alone is responsible for melting roughly 154 tons of ice each season.

The study’s figures remain conservative. The researchers noted that their calculations excluded heat generated by helicopter flights, direct body heat from thousands of climbers, and transport animals like yaks. Including these variables would make the total human impact even higher. While global climate change remains the main cause of retreating glaciers across the Himalayas, researchers warn that concentrating dense human activity and artificial heat sources on an already fragile glacier is unsustainable over the long term.]]> <![CDATA[Why the US will always be the global superpower]]> https://www.scivillage.com/thread-21160.html Sun, 23 Aug 2026 21:01:49 +0000 Syne]]> https://www.scivillage.com/thread-21160.html

https://www.youtube-nocookie.com/embed/0O2EolPa2NM]]>

https://www.youtube-nocookie.com/embed/0O2EolPa2NM]]> <![CDATA[Mount Toba eruption doesn’t seem like it could nearly kill our species]]> https://www.scivillage.com/thread-21059.html Mon, 10 Aug 2026 19:12:13 +0000 C C]]> https://www.scivillage.com/thread-21059.html https://arstechnica.com/science/2026/08/...r-species/

EXCERPTS: Mount Toba was the biggest volcanic eruption in the last 2.6 million years, and some have suggested it nearly wiped out humanity. Around 74,000 years ago, a caldera on what is now Sumatra emptied thousands of cubic kilometers of magma in about two weeks, roughly a thousand times more than Mount Pinatubo spewed out in 1991. “People thought it might have caused massive cooling of the planet, and hence threatened the survival of our ancestors,” says Jinheum Park, a geoscientist at Johannes Gutenberg University in Mainz, Germany.

Park and his colleagues went looking for the records of that catastrophe in the mud taken from the bottom of a small crater lake on the Kenya-Tanzania border. They found instead that the effects of the Mount Toba eruption lasted under two years and amounted to perhaps half a degree of cooling.

[...] “The eruption did cool and dry the region, just not to such an extent as to significantly threaten the survival of humans,” Park argues. Across the 450-year window his team analyzed, eastern equatorial Africa was already sliding from a warmer, wetter regime into a cooler, drier one, tracking a natural cooling trend recorded in Greenland ice. Against that background, Toba’s impact looks tiny. “Our study shows that the magnitude of cooling and drying after Toba was much smaller, and within the natural range of variation in the last glacial–interglacial cycles,” Park says. “Humans had already experienced and survived that.”

The limitation in Park’s study is that Chala is just one lake. “It records the regional climate signals in eastern Africa, but it doesn’t show the impact on the whole globe,” Park explains. “There should be more studies using a similar approach, at more sites where the Toba ash is found.”

The team also hopes similar approaches will be used to learn more about other huge volcanic eruptions like Los Chocoyos in Guatemala and the Oruanui eruption in New Zealand 26,000 years ago. “They were not as big as Toba, but they were still super-eruptions. It would be interesting and exciting to see what happened,” Park says... (MORE - missing details)]]> https://arstechnica.com/science/2026/08/...r-species/

EXCERPTS: Mount Toba was the biggest volcanic eruption in the last 2.6 million years, and some have suggested it nearly wiped out humanity. Around 74,000 years ago, a caldera on what is now Sumatra emptied thousands of cubic kilometers of magma in about two weeks, roughly a thousand times more than Mount Pinatubo spewed out in 1991. “People thought it might have caused massive cooling of the planet, and hence threatened the survival of our ancestors,” says Jinheum Park, a geoscientist at Johannes Gutenberg University in Mainz, Germany.

Park and his colleagues went looking for the records of that catastrophe in the mud taken from the bottom of a small crater lake on the Kenya-Tanzania border. They found instead that the effects of the Mount Toba eruption lasted under two years and amounted to perhaps half a degree of cooling.

[...] “The eruption did cool and dry the region, just not to such an extent as to significantly threaten the survival of humans,” Park argues. Across the 450-year window his team analyzed, eastern equatorial Africa was already sliding from a warmer, wetter regime into a cooler, drier one, tracking a natural cooling trend recorded in Greenland ice. Against that background, Toba’s impact looks tiny. “Our study shows that the magnitude of cooling and drying after Toba was much smaller, and within the natural range of variation in the last glacial–interglacial cycles,” Park says. “Humans had already experienced and survived that.”

The limitation in Park’s study is that Chala is just one lake. “It records the regional climate signals in eastern Africa, but it doesn’t show the impact on the whole globe,” Park explains. “There should be more studies using a similar approach, at more sites where the Toba ash is found.”

The team also hopes similar approaches will be used to learn more about other huge volcanic eruptions like Los Chocoyos in Guatemala and the Oruanui eruption in New Zealand 26,000 years ago. “They were not as big as Toba, but they were still super-eruptions. It would be interesting and exciting to see what happened,” Park says... (MORE - missing details)]]> <![CDATA[Rising seas are swallowing the vast majority of US coastal wetlands]]> https://www.scivillage.com/thread-21018.html Mon, 03 Aug 2026 14:18:55 +0000 C C]]> https://www.scivillage.com/thread-21018.html https://www.eurekalert.org/news-releases/1138147

INTRO: Along the three coasts of the contiguous United States, a silent race unfolds. Fueled by climate change, sea levels rise faster than at any time in recent geologic history. Meanwhile, coastal wetlands cling to a slim lead, lifted on newly accumulated sediments or moving inland as encroaching tides nip at their heels.

Now, the first national-level study of this competition reveals that coastal wetlands — among the country’s most valuable ecosystems, protecting infrastructure and providing homes for wildlife — are losing ground: 84% are gradually inundating, with many on track to transform into open water. Wetlands along the Gulf Coast are generally faring the worst while certain stretches of the Atlantic Coast appear more resilient. Some wetlands may be able to migrate inland or build up sediment fast enough to keep pace with sea level rise, perhaps with the right help from land managers.

“Our study provides wetland managers with new information to help them make better-informed decisions and identify meaningful solutions to issues they may be encountering, including to facilitate wetland migration upslope,” said Glenn Guntenspergen, a coastal wetland ecologist with the U.S. Geological Survey and senior author on the study.

The study will appear Monday, 3 August in Earth’s Future, AGU’s journal for research on the state of the planet and its inhabitants and their future resilience in the Anthropocene... (MORE - no ads)]]> https://www.eurekalert.org/news-releases/1138147

INTRO: Along the three coasts of the contiguous United States, a silent race unfolds. Fueled by climate change, sea levels rise faster than at any time in recent geologic history. Meanwhile, coastal wetlands cling to a slim lead, lifted on newly accumulated sediments or moving inland as encroaching tides nip at their heels.

Now, the first national-level study of this competition reveals that coastal wetlands — among the country’s most valuable ecosystems, protecting infrastructure and providing homes for wildlife — are losing ground: 84% are gradually inundating, with many on track to transform into open water. Wetlands along the Gulf Coast are generally faring the worst while certain stretches of the Atlantic Coast appear more resilient. Some wetlands may be able to migrate inland or build up sediment fast enough to keep pace with sea level rise, perhaps with the right help from land managers.

“Our study provides wetland managers with new information to help them make better-informed decisions and identify meaningful solutions to issues they may be encountering, including to facilitate wetland migration upslope,” said Glenn Guntenspergen, a coastal wetland ecologist with the U.S. Geological Survey and senior author on the study.

The study will appear Monday, 3 August in Earth’s Future, AGU’s journal for research on the state of the planet and its inhabitants and their future resilience in the Anthropocene... (MORE - no ads)]]> <![CDATA[Ships stranded by war could cause marine ‘superspreader’ event (ocean invasiveness)]]> https://www.scivillage.com/thread-20993.html Fri, 31 Jul 2026 16:48:00 +0000 C C]]> https://www.scivillage.com/thread-20993.html The gift that just keeps on giving. The only GOP hope for saving the midterms is Dems very possibly bumbling far more with other things than what Trump has with this unpopular war.
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Ships stranded by war could cause marine ‘superspreader’ event, study warns
https://www.washingtonpost.com/world/202...ists-warn/

INTRO: New research warns that thousands of ships stranded for months by the ongoing war with Iran and the closed Strait of Hormuz could result in “a massive marine invasive species event.”

The study, led by scientists at the University of Maryland and the Woods Hole Oceanographic Institution, said the estimated 1,500 commercial vessels idled by war are likely now coated with marine microbes, algae and invertebrates.

The ships have sat submerged in the same waters for months, creating idle conditions for what the scientists call “biofouling.”

The scientists are now worried about what could happen when these ships eventually resume their journeys around the world. The study cites “the high likelihood” that the vessels will speed the spread of “economically and ecologically damaging invasive species.”

The threats posed by stranded ships are well-known and long-documented... (MORE - details)]]> The gift that just keeps on giving. The only GOP hope for saving the midterms is Dems very possibly bumbling far more with other things than what Trump has with this unpopular war.
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Ships stranded by war could cause marine ‘superspreader’ event, study warns
https://www.washingtonpost.com/world/202...ists-warn/

INTRO: New research warns that thousands of ships stranded for months by the ongoing war with Iran and the closed Strait of Hormuz could result in “a massive marine invasive species event.”

The study, led by scientists at the University of Maryland and the Woods Hole Oceanographic Institution, said the estimated 1,500 commercial vessels idled by war are likely now coated with marine microbes, algae and invertebrates.

The ships have sat submerged in the same waters for months, creating idle conditions for what the scientists call “biofouling.”

The scientists are now worried about what could happen when these ships eventually resume their journeys around the world. The study cites “the high likelihood” that the vessels will speed the spread of “economically and ecologically damaging invasive species.”

The threats posed by stranded ships are well-known and long-documented... (MORE - details)]]> <![CDATA[Venus: geologically dead? Far from it.]]> https://www.scivillage.com/thread-20951.html Mon, 27 Jul 2026 18:11:11 +0000 C C]]> https://www.scivillage.com/thread-20951.html https://astrobiology.com/2026/07/27/venu...r-from-it/

EXCERPTS: Simulations conducted by researchers at ETH Zurich suggest a strong likelihood that Venus’s rift valleys are still geologically active rather than being mere relics of a bygone era, as had been previously believed. This finding reshapes our understanding of Earth’s sister planet and will influence future missions to Venus.

Venus is an inhospitable place, with temperatures soaring to several hundred degrees Celsius and no oceans like those on Earth. Planetary scientists long believed Venus was geologically dormant. However, recent research indicates that Venus remains geologically “alive” and even hosts active volcanoes.

Rift valleys, which indicate tectonic activity, can be vast and resemble those on Earth, such as the African Rift Valley. On Venus, they can span up to 10,000 kilometres.

The timing of these rifts’ formation is uncertain. Geoscientists believe they originated more than 100 million years ago and are therefore remnants of the past.

[...] The models indicate that broad ridges, known as rift flanks, form along the edges of rift valleys when the rifts are geologically young and either still actively moving or have only recently stopped moving. The simulations also suggest that these rifts widen more rapidly than had been previously believed, at a rate of 3 to 10 centimetres per year.

Yang and his colleagues also show that the rift flanks tend to flatten rapidly after movement ceases; the older the rift system, the less steep and narrow its flanks. Unlike Earth, where erosion gradually wears down features, Venus’s flanks subside due to crustal relaxation.

Wide and high rift flanks are not only produced by the computer model but can also be seen in images of the Venusian surface from the Magellan probe during its 1990’s mission.

Based on their simulations and observational data, the researchers conclude that Venus remains an active planet with a more dynamic interior than had been previously believed. “The results help us to better assess the tectonic activity on Venus,” says Gerya.

The results of the ETH researchers’ model could help pinpoint active regions worthy of detailed investigation for these missions. Additionally, the study enhances our understanding of how rocky planets form. Importantly, the researchers aim to uncover clues that could improve the detection of rocky exoplanets... (MORE - missing details)]]> https://astrobiology.com/2026/07/27/venu...r-from-it/

EXCERPTS: Simulations conducted by researchers at ETH Zurich suggest a strong likelihood that Venus’s rift valleys are still geologically active rather than being mere relics of a bygone era, as had been previously believed. This finding reshapes our understanding of Earth’s sister planet and will influence future missions to Venus.

Venus is an inhospitable place, with temperatures soaring to several hundred degrees Celsius and no oceans like those on Earth. Planetary scientists long believed Venus was geologically dormant. However, recent research indicates that Venus remains geologically “alive” and even hosts active volcanoes.

Rift valleys, which indicate tectonic activity, can be vast and resemble those on Earth, such as the African Rift Valley. On Venus, they can span up to 10,000 kilometres.

The timing of these rifts’ formation is uncertain. Geoscientists believe they originated more than 100 million years ago and are therefore remnants of the past.

[...] The models indicate that broad ridges, known as rift flanks, form along the edges of rift valleys when the rifts are geologically young and either still actively moving or have only recently stopped moving. The simulations also suggest that these rifts widen more rapidly than had been previously believed, at a rate of 3 to 10 centimetres per year.

Yang and his colleagues also show that the rift flanks tend to flatten rapidly after movement ceases; the older the rift system, the less steep and narrow its flanks. Unlike Earth, where erosion gradually wears down features, Venus’s flanks subside due to crustal relaxation.

Wide and high rift flanks are not only produced by the computer model but can also be seen in images of the Venusian surface from the Magellan probe during its 1990’s mission.

Based on their simulations and observational data, the researchers conclude that Venus remains an active planet with a more dynamic interior than had been previously believed. “The results help us to better assess the tectonic activity on Venus,” says Gerya.

The results of the ETH researchers’ model could help pinpoint active regions worthy of detailed investigation for these missions. Additionally, the study enhances our understanding of how rocky planets form. Importantly, the researchers aim to uncover clues that could improve the detection of rocky exoplanets... (MORE - missing details)]]> <![CDATA[Earth’s oceans are rapidly losing oxygen. It could destabilize the planet]]> https://www.scivillage.com/thread-20913.html Tue, 21 Jul 2026 16:15:39 +0000 C C]]> https://www.scivillage.com/thread-20913.html https://gizmodo.com/earths-oceans-are-ra...2000787781

INTRO: Oxygen, the element that sustains nearly all multicellular life on Earth, is disappearing from the world’s aquatic ecosystems. In a new review, scientists warn that this rapidly escalating, human-driven crisis threatens to upend the biosphere.

The paper, published June 30 in the journal Limnology and Oceanography, argues that aquatic deoxygenation should be added to the Planetary Boundaries framework. First introduced by a group of 28 internationally renowned scientists in 2009, the framework identifies nine ways that humanity is pushing crucial processes that maintain Earth’s stability and resilience past their limits. They are climate change, ocean acidification, biodiversity loss, atmospheric aerosol loading, stratospheric ozone depletion, freshwater change, land-use change, chemical pollution, and biogeochemical flows.

“The health and stability of our planet depends on the health and stability of aquatic ecosystems, which need oxygen to function normally,” lead author Erica Ferrer, a postdoctoral scholar at the University of California, Santa Barbara’s National Center for Ecological Analysis and Synthesis, said in a statement. “This study is designed to elevate the profile of aquatic deoxygenation as a global threat and show that it does not operate in isolation.” (MORE - dtails)]]> https://gizmodo.com/earths-oceans-are-ra...2000787781

INTRO: Oxygen, the element that sustains nearly all multicellular life on Earth, is disappearing from the world’s aquatic ecosystems. In a new review, scientists warn that this rapidly escalating, human-driven crisis threatens to upend the biosphere.

The paper, published June 30 in the journal Limnology and Oceanography, argues that aquatic deoxygenation should be added to the Planetary Boundaries framework. First introduced by a group of 28 internationally renowned scientists in 2009, the framework identifies nine ways that humanity is pushing crucial processes that maintain Earth’s stability and resilience past their limits. They are climate change, ocean acidification, biodiversity loss, atmospheric aerosol loading, stratospheric ozone depletion, freshwater change, land-use change, chemical pollution, and biogeochemical flows.

“The health and stability of our planet depends on the health and stability of aquatic ecosystems, which need oxygen to function normally,” lead author Erica Ferrer, a postdoctoral scholar at the University of California, Santa Barbara’s National Center for Ecological Analysis and Synthesis, said in a statement. “This study is designed to elevate the profile of aquatic deoxygenation as a global threat and show that it does not operate in isolation.” (MORE - dtails)]]> <![CDATA[Alien geochemistry found inside meteorite that struck New Jersey home]]> https://www.scivillage.com/thread-20871.html Fri, 17 Jul 2026 01:10:45 +0000 C C]]> https://www.scivillage.com/thread-20871.html https://www.seti.org/news/alien-world-ch...meteorite/

KEY POINTS: A meteorite crashed through the roof of a Hillsborough, New Jersey home on July 16, 2024. The meteorite, named Hillsborough, is only the second observed fall of a rare primitive CM1/2 carbonaceous chondrite, making it one of the most scientifically valuable meteorites ever recovered.

The meteorite's pristine condition, preserved by the homeowner immediately after impact, allowed scientists to study fragile minerals and organic compounds rarely seen in recovered meteorites. Researchers found preserved bits from near the surface of the original asteroid where it experienced concentrated salty fluids—a process not previously known from this type of asteroid.

Hillsborough contains a diverse suite of carbon-bearing compounds, amino acids, and other prebiotic molecules that help scientists understand what building blocks of life may have been delivered to the early Earth. The findings provide new insight into the role of water, brines, and asteroid chemistry in shaping the organic inventory of the early solar system.

The international research team's results are published in Science Advances...... (MORE - details)]]> https://www.seti.org/news/alien-world-ch...meteorite/

KEY POINTS: A meteorite crashed through the roof of a Hillsborough, New Jersey home on July 16, 2024. The meteorite, named Hillsborough, is only the second observed fall of a rare primitive CM1/2 carbonaceous chondrite, making it one of the most scientifically valuable meteorites ever recovered.

The meteorite's pristine condition, preserved by the homeowner immediately after impact, allowed scientists to study fragile minerals and organic compounds rarely seen in recovered meteorites. Researchers found preserved bits from near the surface of the original asteroid where it experienced concentrated salty fluids—a process not previously known from this type of asteroid.

Hillsborough contains a diverse suite of carbon-bearing compounds, amino acids, and other prebiotic molecules that help scientists understand what building blocks of life may have been delivered to the early Earth. The findings provide new insight into the role of water, brines, and asteroid chemistry in shaping the organic inventory of the early solar system.

The international research team's results are published in Science Advances...... (MORE - details)]]> <![CDATA[The missing 500 million years: Cosmic bombardment melted Earth’s first crust]]> https://www.scivillage.com/thread-20802.html Mon, 06 Jul 2026 15:33:04 +0000 C C]]> https://www.scivillage.com/thread-20802.html https://arstechnica.com/science/2026/07/...rst-crust/

INTRO: Earth is the only planet we know of with buoyant, silica-rich continents. But, despite decades of research, geologists still don’t agree on how they formed. “The continents started appearing around about four billion years ago—that’s the oldest continental rock we know about,” said Tim Johnson, a geologist at Curtin University in Perth, Australia. “The Earth is four and a half billion years old, so why they started appearing then is unknown, as is the mechanism to make that continental crust.”

Johnson and his colleagues are now arguing that the formation of continents on Earth was caused largely by an intense, sustained barrage of asteroid impacts that kept the early crust hot and thin enough to make buoyant continents possible. In short, the lands we live on are here because of ancient bombardment from space.

The problem with studying the formation of continents is that the geological evidence of this process is almost gone. The oldest known continental-type rocks crystallized around 4.03 billion years ago, right at the end of the Hadean eon (the earliest era in Earth’s history, spanning the first 500 million years of its existence). Rare basaltic rocks date back about 4.2 billion years, and a handful of the oldest zircon crystals push the record back to 4.4 billion years. Beyond that, there’s hardly anything else. So, scientists looking into the origin of continents had to rely largely on educated guesses. “There are huge debates about what was going on in the early Earth, because the data is so scarce,” Johnson said.

One dominant idea holds that plate tectonics, much like today’s, was already running in the Hadean, with continental crust forming above subduction zones—areas where tectonic plates collide. The other claims that early Earth was too hot for rigid plates, and that crust instead formed above mantle plumes rising from deep within the planet, a phenomenon comparable, Johnson said, to the wax blobs rising inside a lava lamp.

The issue with both these ideas, though, was that Earth, based on most models, appeared too cold for all this to happen. “People have tried to understand Earth’s heat budget through time, and nobody could make it fit,” Johnson said. “Nobody could make it fit because we did not consider the energy coming from outside of Earth.” This energy, he argues, came from asteroid and meteorite impacts that were far more frequent back when the solar system was young. Adding these impacts to the early Earth’s heat budget, though, proved rather challenging because Earth has a peculiar way of healing its scars.

The reason we don’t really know what was happening on Earth four billion years ago is that plate tectonics effectively recycles the surface of the planet back into the mantle. “One place where we do know what was going on back then is the Moon,” Johnson said. “We have sent people there. We have collected sample from there. We have immense amounts of high-quality data from the Moon.” Because the Moon does not have plate tectonics, its crust is a single, solid, continuous shell. And this shell, Johnson’s team noted, is peppered with impact craters.

Calibrated against dated lunar samples, crater counts on the Moon let Johnson’s team estimate how frequently large bodies were hitting our closest celestial neighbor shortly after the Earth had formed... (MORE - details)

PAPER: http://dx.doi.org/10.1126/science.aeb5402]]> https://arstechnica.com/science/2026/07/...rst-crust/

INTRO: Earth is the only planet we know of with buoyant, silica-rich continents. But, despite decades of research, geologists still don’t agree on how they formed. “The continents started appearing around about four billion years ago—that’s the oldest continental rock we know about,” said Tim Johnson, a geologist at Curtin University in Perth, Australia. “The Earth is four and a half billion years old, so why they started appearing then is unknown, as is the mechanism to make that continental crust.”

Johnson and his colleagues are now arguing that the formation of continents on Earth was caused largely by an intense, sustained barrage of asteroid impacts that kept the early crust hot and thin enough to make buoyant continents possible. In short, the lands we live on are here because of ancient bombardment from space.

The problem with studying the formation of continents is that the geological evidence of this process is almost gone. The oldest known continental-type rocks crystallized around 4.03 billion years ago, right at the end of the Hadean eon (the earliest era in Earth’s history, spanning the first 500 million years of its existence). Rare basaltic rocks date back about 4.2 billion years, and a handful of the oldest zircon crystals push the record back to 4.4 billion years. Beyond that, there’s hardly anything else. So, scientists looking into the origin of continents had to rely largely on educated guesses. “There are huge debates about what was going on in the early Earth, because the data is so scarce,” Johnson said.

One dominant idea holds that plate tectonics, much like today’s, was already running in the Hadean, with continental crust forming above subduction zones—areas where tectonic plates collide. The other claims that early Earth was too hot for rigid plates, and that crust instead formed above mantle plumes rising from deep within the planet, a phenomenon comparable, Johnson said, to the wax blobs rising inside a lava lamp.

The issue with both these ideas, though, was that Earth, based on most models, appeared too cold for all this to happen. “People have tried to understand Earth’s heat budget through time, and nobody could make it fit,” Johnson said. “Nobody could make it fit because we did not consider the energy coming from outside of Earth.” This energy, he argues, came from asteroid and meteorite impacts that were far more frequent back when the solar system was young. Adding these impacts to the early Earth’s heat budget, though, proved rather challenging because Earth has a peculiar way of healing its scars.

The reason we don’t really know what was happening on Earth four billion years ago is that plate tectonics effectively recycles the surface of the planet back into the mantle. “One place where we do know what was going on back then is the Moon,” Johnson said. “We have sent people there. We have collected sample from there. We have immense amounts of high-quality data from the Moon.” Because the Moon does not have plate tectonics, its crust is a single, solid, continuous shell. And this shell, Johnson’s team noted, is peppered with impact craters.

Calibrated against dated lunar samples, crater counts on the Moon let Johnson’s team estimate how frequently large bodies were hitting our closest celestial neighbor shortly after the Earth had formed... (MORE - details)

PAPER: http://dx.doi.org/10.1126/science.aeb5402]]> <![CDATA[The strange new rocks that wouldn't exist without us]]> https://www.scivillage.com/thread-20659.html Wed, 17 Jun 2026 16:46:45 +0000 C C]]> https://www.scivillage.com/thread-20659.html https://aeon.co/essays/the-strange-rocks...without-us

EXCERPTS: As a geologist, I have studied various types of natural rocks, but recently I have become interested in ‘anthropogenic geomaterials’ – things like industrial slag – and how they become entwined in geological and environmental processes. I came to Workington originally to look at the slag...

[...] For geologists who study rock day in day out, it’s such a foundational concept that we rarely stop to ask what’s the actual definition of a rock. So I quizzed a few, in a non-statistical, non-exhaustive informal survey of geological friends and colleagues. When asked, hardness featured heavily in people’s definitions, and most agreed that a rock is a substance made of minerals. There was less agreement with the dictionary when it came to size though – the OED and Cambridge definitions point to rock being a large mass or even the whole Earth, but some geologists would argue that a grain of sand could be considered a rock. It is, after all, hard and made of minerals, like quartz or feldspar.

Perhaps the most debated part of the definition, and the one most relevant to this essay, is whether a rock must be natural. The overwhelming majority of rocks on Earth form through natural geological processes such as solidification of molten lava flows, or compression and compaction deep within the Earth. However, everyday materials created by humans such as pottery, concrete or bricks are made of minerals. Are these rocks? Many would say not. Perhaps that’s because these materials are processed, manufactured, and more often found in the built environment rather than in wild landscapes. As we discovered at Workington, though, the border between natural and human is more difficult to draw.

If you were to tell anybody about a pile of thousands of tonnes of industrial waste, most people’s reaction would probably be to recoil in disgust. In many cases this holds true, such as when old landfills of municipal waste are exposed through coastal erosion, resulting in old rags, sanitary products and medical waste leaking onto coastlines. There’s something about a wet muddy bit of fabric on the beach that just gives you the ‘ick’. However, the vast majority of visitors to a place such as Workington would be none the wiser that they were in the proximity of a huge volume of industrial waste.

[...] Human beings have created slag for thousands of years, ever since people started working with metals. While in the past it was simply dumped, today the material is often reused in other settings, such as cement production, road construction, agriculture, or along railway lines as ballast.

[...] Once the slag that makes the cliff was poured and solidified, human involvement in the story ends. Workington is quite an exposed coast, with storms rolling in over the Irish Sea. The waves crashing against the slag cliffs causes them to erode – just like natural coastal cliffs – chipping off small, angular pebble-sized pieces. The wave and tide action then rounds off the corners.

[...] Anthropogenic rock formation is a frontier research area with relatively few examples documented. However, once we understood what was going on at Workington, we were able to identify the same process occurring in other places where iron and steel slag had been dumped historically, with examples in northern England and southwest Scotland. We also started to find evidence of ‘rocks’ forming from other human-made materials, or where human processes had been key.

[...] Geologists are also learning that the more ‘solid’ examples of industrial waste can actually bring many benefits. Slag has carbon dioxide mineralising properties – essentially scrubbing CO2 out of the atmosphere, giving it the opportunity to help us in our fight against anthropogenic climate change. Additionally, old slag banks are known to be havens for rare species of plants and invertebrates – their gravelly and alkaline nature makes them an unusual habitat. However, if the gravelly slag has fused together into a rock, it may be more difficult for ecological colonisation. The study of such anthropogenic materials is a frontier area of research and there remain many unknowns.

In our discipline, we geologists are used to looking back into the distant past, perhaps to learn lessons about what our geological future might look like. With these anthropogenic rocks it is difficult to do this, as no ancient analogues exist... (MORE - missing details)]]> https://aeon.co/essays/the-strange-rocks...without-us

EXCERPTS: As a geologist, I have studied various types of natural rocks, but recently I have become interested in ‘anthropogenic geomaterials’ – things like industrial slag – and how they become entwined in geological and environmental processes. I came to Workington originally to look at the slag...

[...] For geologists who study rock day in day out, it’s such a foundational concept that we rarely stop to ask what’s the actual definition of a rock. So I quizzed a few, in a non-statistical, non-exhaustive informal survey of geological friends and colleagues. When asked, hardness featured heavily in people’s definitions, and most agreed that a rock is a substance made of minerals. There was less agreement with the dictionary when it came to size though – the OED and Cambridge definitions point to rock being a large mass or even the whole Earth, but some geologists would argue that a grain of sand could be considered a rock. It is, after all, hard and made of minerals, like quartz or feldspar.

Perhaps the most debated part of the definition, and the one most relevant to this essay, is whether a rock must be natural. The overwhelming majority of rocks on Earth form through natural geological processes such as solidification of molten lava flows, or compression and compaction deep within the Earth. However, everyday materials created by humans such as pottery, concrete or bricks are made of minerals. Are these rocks? Many would say not. Perhaps that’s because these materials are processed, manufactured, and more often found in the built environment rather than in wild landscapes. As we discovered at Workington, though, the border between natural and human is more difficult to draw.

If you were to tell anybody about a pile of thousands of tonnes of industrial waste, most people’s reaction would probably be to recoil in disgust. In many cases this holds true, such as when old landfills of municipal waste are exposed through coastal erosion, resulting in old rags, sanitary products and medical waste leaking onto coastlines. There’s something about a wet muddy bit of fabric on the beach that just gives you the ‘ick’. However, the vast majority of visitors to a place such as Workington would be none the wiser that they were in the proximity of a huge volume of industrial waste.

[...] Human beings have created slag for thousands of years, ever since people started working with metals. While in the past it was simply dumped, today the material is often reused in other settings, such as cement production, road construction, agriculture, or along railway lines as ballast.

[...] Once the slag that makes the cliff was poured and solidified, human involvement in the story ends. Workington is quite an exposed coast, with storms rolling in over the Irish Sea. The waves crashing against the slag cliffs causes them to erode – just like natural coastal cliffs – chipping off small, angular pebble-sized pieces. The wave and tide action then rounds off the corners.

[...] Anthropogenic rock formation is a frontier research area with relatively few examples documented. However, once we understood what was going on at Workington, we were able to identify the same process occurring in other places where iron and steel slag had been dumped historically, with examples in northern England and southwest Scotland. We also started to find evidence of ‘rocks’ forming from other human-made materials, or where human processes had been key.

[...] Geologists are also learning that the more ‘solid’ examples of industrial waste can actually bring many benefits. Slag has carbon dioxide mineralising properties – essentially scrubbing CO2 out of the atmosphere, giving it the opportunity to help us in our fight against anthropogenic climate change. Additionally, old slag banks are known to be havens for rare species of plants and invertebrates – their gravelly and alkaline nature makes them an unusual habitat. However, if the gravelly slag has fused together into a rock, it may be more difficult for ecological colonisation. The study of such anthropogenic materials is a frontier area of research and there remain many unknowns.

In our discipline, we geologists are used to looking back into the distant past, perhaps to learn lessons about what our geological future might look like. With these anthropogenic rocks it is difficult to do this, as no ancient analogues exist... (MORE - missing details)]]> <![CDATA[Good news—we have extra time before the Sun ends life on Earth]]> https://www.scivillage.com/thread-20650.html Tue, 16 Jun 2026 20:07:41 +0000 C C]]> https://www.scivillage.com/thread-20650.html https://arstechnica.com/science/2026/06/...-on-earth/

EXCERPT: The, uh, good news about these estimates for the demise of complex life on Earth is that they’re actually a bit more optimistic than most previous studies. That’s down to the 3D model producing a little less warming for a brighter Sun, the expectation that CO2 declines more slowly over time, and a slight expansion of the CO2 range believed to be survivable by plants. Many previous estimates had put life’s expiration date at less than 1 billion years from now.

Obviously, there are a bunch of additional considerations that could significantly alter this story, and the researchers mention a few. If civilization persists long enough to see some of these changes, geoengineering would certainly be an option—like spreading aerosols in the stratosphere to reflect sunlight, for example.

There are even some wilder suggestions out there, like moving Earth’s orbit farther from the Sun or removing some of the Sun’s mass to tame the red giant. (We have a billion years to work on the logistics, after all.)

Less speculatively, evolution could have a say in the physiological limits of Earth’s plants. Any adaptations that expand the range of survivability would extend the timeline.

Ultimately, the point of modeling this kind of thing is not to make a confident prediction. Apart from the simple natural curiosity about what will happen to our world, this is also relevant to wondering about the potential for life on other worlds. The window of time during which life on Earth is possible tells us something about where to look outside our Solar System.

Land plants have been present on Earth for almost 500 million years, and if this new estimate is right, they could stick around for almost 1.9 billion more. As was the case for a few billion years early on, microbial life might again have the place to themselves for a while after that... (MORE - missing detail)

PAPER: http://dx.doi.org/10.1029/2025JD045586]]> https://arstechnica.com/science/2026/06/...-on-earth/

EXCERPT: The, uh, good news about these estimates for the demise of complex life on Earth is that they’re actually a bit more optimistic than most previous studies. That’s down to the 3D model producing a little less warming for a brighter Sun, the expectation that CO2 declines more slowly over time, and a slight expansion of the CO2 range believed to be survivable by plants. Many previous estimates had put life’s expiration date at less than 1 billion years from now.

Obviously, there are a bunch of additional considerations that could significantly alter this story, and the researchers mention a few. If civilization persists long enough to see some of these changes, geoengineering would certainly be an option—like spreading aerosols in the stratosphere to reflect sunlight, for example.

There are even some wilder suggestions out there, like moving Earth’s orbit farther from the Sun or removing some of the Sun’s mass to tame the red giant. (We have a billion years to work on the logistics, after all.)

Less speculatively, evolution could have a say in the physiological limits of Earth’s plants. Any adaptations that expand the range of survivability would extend the timeline.

Ultimately, the point of modeling this kind of thing is not to make a confident prediction. Apart from the simple natural curiosity about what will happen to our world, this is also relevant to wondering about the potential for life on other worlds. The window of time during which life on Earth is possible tells us something about where to look outside our Solar System.

Land plants have been present on Earth for almost 500 million years, and if this new estimate is right, they could stick around for almost 1.9 billion more. As was the case for a few billion years early on, microbial life might again have the place to themselves for a while after that... (MORE - missing detail)

PAPER: http://dx.doi.org/10.1029/2025JD045586]]> <![CDATA[Interesting Seismic Activity/Possible Volcanism Near South Mono, California]]> https://www.scivillage.com/thread-20553.html Mon, 01 Jun 2026 13:25:37 +0000 PLCoulomb]]> https://www.scivillage.com/thread-20553.html https://earthquake.usgs.gov/earthquakes/.../executive

I keep an eye on unusual seismic readings and this one caught my attention.  From the perspective of two seismographs, I noticed that waves associated with this temblor were time-compressed into a sharp, punctuated burst of activity, but the same waves were spread out evenly as one might expect as measured from other stations.  The two nearest stations, one in Nevada and one in Columbia, CA show this compression.

It's my hypothesis that fluids of tapered density can cause sound and heat to become compressed as they are conveyed over distance.  Magma, for example, if under extreme pressure in one area might gradually release its pressure, resulting in a pressure gradient which causes seismic waves to travel at variable speeds through the liquid, causing seismic waves emitted at a latter point in time to be able to catch up with the initial waves, causing compression over time.  If that's what's occurring here, it could indicate that a dormant volcano in the High Sierras and, more specifically, in the South Mono area is getting ready to go active.  These are rarely active, but if they were to become active again, it could be a disaster for the people in the area.

The waves are being compressed as a result of density gradually decreasing over the distance from the epicenter of this foreshock toward the detector.  Mono Lake, Lee Vining and Yosemite could become volcanically active based upon these readings, but the USGS quite frankly doesn't know what it's doing.  It's something to watch.]]> https://earthquake.usgs.gov/earthquakes/.../executive

I keep an eye on unusual seismic readings and this one caught my attention.  From the perspective of two seismographs, I noticed that waves associated with this temblor were time-compressed into a sharp, punctuated burst of activity, but the same waves were spread out evenly as one might expect as measured from other stations.  The two nearest stations, one in Nevada and one in Columbia, CA show this compression.

It's my hypothesis that fluids of tapered density can cause sound and heat to become compressed as they are conveyed over distance.  Magma, for example, if under extreme pressure in one area might gradually release its pressure, resulting in a pressure gradient which causes seismic waves to travel at variable speeds through the liquid, causing seismic waves emitted at a latter point in time to be able to catch up with the initial waves, causing compression over time.  If that's what's occurring here, it could indicate that a dormant volcano in the High Sierras and, more specifically, in the South Mono area is getting ready to go active.  These are rarely active, but if they were to become active again, it could be a disaster for the people in the area.

The waves are being compressed as a result of density gradually decreasing over the distance from the epicenter of this foreshock toward the detector.  Mono Lake, Lee Vining and Yosemite could become volcanically active based upon these readings, but the USGS quite frankly doesn't know what it's doing.  It's something to watch.]]>