insidescience--2020-09-09--The Carbon Cycle Runs Deep

The Carbon Cycle Runs Deep

New research on diamonds found deep in the Earth 's crust suggests that the planet 's carbon cycle reaches far underground .
( Inside Science ) -- Diamonds from deep underground are now revealing secrets of how the carbon vital to life on this planet cycles between Earth 's interior and its surface , a new study finds .
The carbon that all life on Earth is based on moves through the planet 's atmosphere , oceans and crust in a pattern called the carbon cycle .
This cycle plays a key role in climate ; for instance , carbon @ @ @ @ @ @ @ warm the globe .
The most well-understood parts of the carbon cycle occur at or near the Earth 's surface , but findings have recently suggested the whole cycle might extend much deeper into the planet 's interior than is often thought .
For example , ocean sediments or oceanic crust can plunge into the Earth 's mantle , the hot rock layer between the crust and core , when one tectonic plate gets forced , or subducted , under another .
`` If we want to understand why our planet has evolved @ @ @ @ @ @ @ and how the surfaces and atmospheres of other planets may be shaped by their interior processes , we need to better understand the carbon cycle , '' said study lead author Margo Regier , a geochemist at the University of Alberta in Edmonton , Canada .
One way to solve this mystery is to analyze `` superdeep '' diamonds -- ones from depths of more than 250 kilometers -- to see what carbon from the crust they might contain .
Regier and her colleagues investigated superdeep diamonds bought from miners in Kankan , @ @ @ @ @ @ @ on the kinds of mineral impurities found within the diamonds , these gems originated roughly 250 to 700 kilometers deep in the lower mantle .
The researchers examined the diamonds and bits of minerals within them , focusing on the different isotopes of carbon , oxygen and nitrogen they possessed .
The ratios of the different isotopes vary depending on the origin of the material that ultimately made the diamonds .
The researchers discovered that superdeep diamonds originating above depths of 660 kilometers appear to be mainly derived from volcanic oceanic crust .
@ @ @ @ @ @ @ diamonds originating below 660 kilometers revealed they likely formed from carbon from the lower mantle , with little to no carbon from the crust .
This suggests that carbon from the crust only cycles so deep before cycling upward .
`` This is really important for our understanding of the whole carbon cycle , '' said mantle geochemist Yaakov Weiss at the Hebrew University in Jerusalem , who did not take part in this research .
The scientists noted the deep mantle is rich in metallic iron , and carbon bonds well to @ @ @ @ @ @ @ this iron-carbon alloy breaks down when exposed to water , and the liberated carbon may form diamonds .
They suggested this was likely after the breakdown of water-rich minerals in subducting rock .
Future research should investigate superdeep diamonds from across the Earth to get a truly global picture of the deep carbon cycle , said petrologist Michael Walter at the Carnegie Institution for Science in Washington , D.C. , who did not participate in this study .
Regier and her colleagues also plan to investigate silicon and magnesium isotopes within superdeep diamonds @ @ @ @ @ @ @ the crust are circulating within the deep mantle , she said .
The scientists detailed their findings online Sept. 9 in the journal Nature .

New research on diamonds found deep in the Earth's crust suggests that the planet's carbon cycle reaches far underground.
Charles Q. Choi, Contributor
(Inside Science) -- Diamonds from deep underground are now revealing secrets of how the carbon vital to life on this planet cycles between Earth's interior and its surface, a new study finds.
The carbon that all life on Earth is based on moves through the planet's atmosphere, oceans and crust in a pattern called the carbon cycle. This cycle plays a key role in climate; for instance, carbon dioxide traps heat from the sun to warm the globe.
The most well-understood parts of the carbon cycle occur at or near the Earth's surface, but findings have recently suggested the whole cycle might extend much deeper into the planet's interior than is often thought. For example, ocean sediments or oceanic crust can plunge into the Earth's mantle, the hot rock layer between the crust and core, when one tectonic plate gets forced, or subducted, under another.
"If we want to understand why our planet has evolved into the habitable state it is today and how the surfaces and atmospheres of other planets may be shaped by their interior processes, we need to better understand the carbon cycle," said study lead author Margo Regier, a geochemist at the University of Alberta in Edmonton, Canada.
One way to solve this mystery is to analyze "superdeep" diamonds -- ones from depths of more than 250 kilometers -- to see what carbon from the crust they might contain.
Regier and her colleagues investigated superdeep diamonds bought from miners in Kankan, Guinea, in West Africa. Based on the kinds of mineral impurities found within the diamonds, these gems originated roughly 250 to 700 kilometers deep in the lower mantle. The researchers examined the diamonds and bits of minerals within them, focusing on the different isotopes of carbon, oxygen and nitrogen they possessed. The ratios of the different isotopes vary depending on the origin of the material that ultimately made the diamonds.
The researchers discovered that superdeep diamonds originating above depths of 660 kilometers appear to be mainly derived from volcanic oceanic crust.
In contrast, the isotope ratios from diamonds originating below 660 kilometers revealed they likely formed from carbon from the lower mantle, with little to no carbon from the crust. This suggests that carbon from the crust only cycles so deep before cycling upward. "This is really important for our understanding of the whole carbon cycle," said mantle geochemist Yaakov Weiss at the Hebrew University in Jerusalem, who did not take part in this research.
The scientists noted the deep mantle is rich in metallic iron, and carbon bonds well to it at those depths. However, this iron-carbon alloy breaks down when exposed to water, and the liberated carbon may form diamonds. They suggested this was likely after the breakdown of water-rich minerals in subducting rock.
Future research should investigate superdeep diamonds from across the Earth to get a truly global picture of the deep carbon cycle, said petrologist Michael Walter at the Carnegie Institution for Science in Washington, D.C., who did not participate in this study. Regier and her colleagues also plan to investigate silicon and magnesium isotopes within superdeep diamonds to learn more about how materials from the crust are circulating within the deep mantle, she said.
The scientists detailed their findings online Sept. 9 in the journal Nature.


insidescience--2020-09-23--Tumors Under Physical Stress Inside the Body May Not Respond as Well to Chemotherapy

Tumors Under Physical Stress Inside the Body May Not Respond as Well to Chemotherapy Researchers found that confined tumors are more resistant to drug treatments .
( Inside Science ) -- Scientists have long known that the biochemical environment around living cells can encourage or suppress their growth .
More recently , researchers have begun recognizing that mechanical cues such as pushing or stretching may be equally important .
Now , researchers have found that cancer cells that are compressed by other tissue may not respond as well to chemotherapy drugs .
Their in vitro experiments on model tumors point @ @ @ @ @ @ @ alleviates compressive stress experienced by cancer cells , which may then boost the effects of chemotherapy .
The study was published online Friday in the journal Physical Review Letters .
`` Mechanical stress is increasingly recognized to be important for cancer , and clinicians are only just starting to account for this , '' said study author Morgan Delarue , a biophysicist at the French National Centre for Scientific Research .
`` Our results suggest that , when designing new therapies , we should also account for their effects on a tumor ’ @ @ @ @ @ @ @ live in a diverse , bustling neighborhood made up of connective tissue cells , immune cells , blood cells , collagen , enzymes and proteins .
This so-called microenvironment around the tumor plays a crucial role in the development and progression of cancer .
In addition to biochemical signals from the microenvironment , physical signals such as changes in tissue stiffness or pressure can drive tumor growth and metastasis .
Delarue and his colleagues work with tumor spheroids -- basically , balls of cancer cells grown in a culture medium that mimic real @ @ @ @ @ @ @ they demonstrated that compressing tumor spheroids inhibits their growth rate .
That ’ s because as a solid tumor grows within a limited space , it has to push harder against its surrounding environment , making it unable to grow or spread as quickly .
The current study explores the relationship between compressive stress and chemotherapy .
One of the biggest challenges in cancer therapy is drug resistance , where a given chemotherapy or other medication no longer works for a patient , even in cases where it once did .
Increased drug @ @ @ @ @ @ @ options , leaving patients vulnerable to disease recurrence and death .
`` Our question was , would mechanical stress lower the efficacy of a given chemotherapeutic by decreasing the amount of target cells ? ''
said Delarue .
Chemotherapy specifically targets cells that are growing and dividing , so he wondered what the effects of growth-inhibiting compression would be on such a drug .
The researchers attempted to find the answer by compressing tumor spheroids made of pancreatic cancer cells and adding gemcitabine , a chemotherapy medication .
The spheroids were embedded and @ @ @ @ @ @ @ way to introduce growth-induced pressure .
While the unconfined spheroids decreased in size by roughly 30 % to 40 % when treated with gemcitabine , their confined counterparts shrank by only 10 % .
Delarue and his colleagues came up with two possible explanations for this result .
One is that compressive stress triggers a series of chemical signals inside the cell that inhibits the drug directly .
The other hypothesis involves a more indirect route , where compression of the tumor leads to a decrease in tumor growth rate , which in @ @ @ @ @ @ @ When these assumptions were incorporated into a mathematical model , the second mechanism correctly predicted the experimental data .
This result suggests a novel mechanical form of drug resistance may arise from compressive stress .
Cancer cells sense pressure and release signals to stop tumor growth , and the lack of growing cells leave chemotherapy with nothing to target .
Delarue suggests a possible strategy to overcome chemotherapy resistance would be to give patients a drug that reduces compressive stress in order to trigger cancer cells to grow and divide again .
He @ @ @ @ @ @ @ , but if tumor growth is carefully timed and controlled , it could allow chemotherapy to eradicate the tumor once and for all .
`` This is a very interesting study showing in vitro that mechanical compression of cancer cells can cause resistance to chemotherapy , '' said Triantafyllos Stylianopoulos , a biophysicist at the University of Cyprus who was not involved in the research .
`` Tumor microenvironment targeting with the aim to alleviate mechanical forces in tumors is promising , and this study nicely supports this concept , providing another argument @ @ @ @ @ @ @ , putting the idea of drugs that reduce stress on tumors into practice has proved less straightforward .
Animal studies in which chemotherapy was combined with hyaluronidase , an enzyme that alleviates compressive forces in the tumor microenvironment , looked promising .
But in 2019 , a clinical trial in human patients with metastatic pancreatic cancer failed to demonstrate an improvement in overall survival , and Halozyme Therapeutics halted drug development as a result .
Stylianopoulos believes that in order to be effective , mechano-therapeutic drugs must address both the tumor 's mechanical @ @ @ @ @ @ @ a drug originally used to treat hypertension , has shown some promise in these areas .
John D. Martin , head of research at nanotechnology company NanoCarrier , agreed that the results support the incorporation of mechanical stress as a factor when developing new therapies for cancer .
Martin and his colleagues recently published a study on dexamethasone , a drug with anti-inflammatory properties , showing that it reduces tissue stiffness and solid stress in the tumor microenvironment .
`` This work provides evidence of an additional rationale for using solid stress-alleviating therapies @ @ @ @ @ @ @ with chemotherapy , '' said Martin , who was also not involved with the study .
`` Solid stress-alleviating therapies combined with chemoradiation are already advancing in clinical trials , and these findings support this course . ''

Researchers found that confined tumors are more resistant to drug treatments.
Meeri Kim, Contributor
(Inside Science) -- Scientists have long known that the biochemical environment around living cells can encourage or suppress their growth. More recently, researchers have begun recognizing that mechanical cues such as pushing or stretching may be equally important.
Now, researchers have found that cancer cells that are compressed by other tissue may not respond as well to chemotherapy drugs. Their in vitro experiments on model tumors point to a possible strategy for treatment that alleviates compressive stress experienced by cancer cells, which may then boost the effects of chemotherapy. The study was published online Friday in the journal Physical Review Letters.
"Mechanical stress is increasingly recognized to be important for cancer, and clinicians are only just starting to account for this," said study author Morgan Delarue, a biophysicist at the French National Centre for Scientific Research. "Our results suggest that, when designing new therapies, we should also account for their effects on a tumor’s mechanical environment."
Cancer cells live in a diverse, bustling neighborhood made up of connective tissue cells, immune cells, blood cells, collagen, enzymes and proteins. This so-called microenvironment around the tumor plays a crucial role in the development and progression of cancer. In addition to biochemical signals from the microenvironment, physical signals such as changes in tissue stiffness or pressure can drive tumor growth and metastasis.
Delarue and his colleagues work with tumor spheroids -- basically, balls of cancer cells grown in a culture medium that mimic real tumors in the lab. Previously, they demonstrated that compressing tumor spheroids inhibits their growth rate. That’s because as a solid tumor grows within a limited space, it has to push harder against its surrounding environment, making it unable to grow or spread as quickly.
The current study explores the relationship between compressive stress and chemotherapy. One of the biggest challenges in cancer therapy is drug resistance, where a given chemotherapy or other medication no longer works for a patient, even in cases where it once did. Increased drug resistance means the loss of viable treatment options, leaving patients vulnerable to disease recurrence and death.
"Our question was, would mechanical stress lower the efficacy of a given chemotherapeutic by decreasing the amount of target cells?" said Delarue. Chemotherapy specifically targets cells that are growing and dividing, so he wondered what the effects of growth-inhibiting compression would be on such a drug.
The researchers attempted to find the answer by compressing tumor spheroids made of pancreatic cancer cells and adding gemcitabine, a chemotherapy medication. The spheroids were embedded and confined within a polymer solid as a way to introduce growth-induced pressure. While the unconfined spheroids decreased in size by roughly 30% to 40% when treated with gemcitabine, their confined counterparts shrank by only 10%.
Delarue and his colleagues came up with two possible explanations for this result. One is that compressive stress triggers a series of chemical signals inside the cell that inhibits the drug directly. The other hypothesis involves a more indirect route, where compression of the tumor leads to a decrease in tumor growth rate, which in turn would make chemotherapy less effective.
When these assumptions were incorporated into a mathematical model, the second mechanism correctly predicted the experimental data. This result suggests a novel mechanical form of drug resistance may arise from compressive stress. Cancer cells sense pressure and release signals to stop tumor growth, and the lack of growing cells leave chemotherapy with nothing to target.
Delarue suggests a possible strategy to overcome chemotherapy resistance would be to give patients a drug that reduces compressive stress in order to trigger cancer cells to grow and divide again. He acknowledges the counterintuitive nature of this method, but if tumor growth is carefully timed and controlled, it could allow chemotherapy to eradicate the tumor once and for all.
"This is a very interesting study showing in vitro that mechanical compression of cancer cells can cause resistance to chemotherapy," said Triantafyllos Stylianopoulos, a biophysicist at the University of Cyprus who was not involved in the research. "Tumor microenvironment targeting with the aim to alleviate mechanical forces in tumors is promising, and this study nicely supports this concept, providing another argument in favor of it."
However, putting the idea of drugs that reduce stress on tumors into practice has proved less straightforward. Animal studies in which chemotherapy was combined with hyaluronidase, an enzyme that alleviates compressive forces in the tumor microenvironment, looked promising. But in 2019, a clinical trial in human patients with metastatic pancreatic cancer failed to demonstrate an improvement in overall survival, and Halozyme Therapeutics halted drug development as a result.
Stylianopoulos believes that in order to be effective, mechano-therapeutic drugs must address both the tumor's mechanical properties and its microenvironment. Losartan, a drug originally used to treat hypertension, has shown some promise in these areas.
John D. Martin, head of research at nanotechnology company NanoCarrier, agreed that the results support the incorporation of mechanical stress as a factor when developing new therapies for cancer. Martin and his colleagues recently published a study on dexamethasone, a drug with anti-inflammatory properties, showing that it reduces tissue stiffness and solid stress in the tumor microenvironment.
"This work provides evidence of an additional rationale for using solid stress-alleviating therapies such as losartan and dexamethasone in combination with chemotherapy," said Martin, who was also not involved with the study. "Solid stress-alleviating therapies combined with chemoradiation are already advancing in clinical trials, and these findings support this course."


insidescience--2020-09-25--Severe Marine Heat Waves Linked to Human-Caused Warming

Unusually hot zones in the ocean will last longer and occur more often in the coming century .
( Inside Science ) -- Marine heat waves can wreak havoc on fisheries , coral reefs , kelp forests and other vital ocean ecosystems .
In a new paper in the journal Science , climate scientists revealed strong evidence that future marine heat waves will intensify and occur much more frequently as a direct result of anthropogenic climate change .
The scientists , led by postdoctoral researcher Charlotte Laufkötter at the University of Bern in Switzerland , focused on seven well-documented marine @ @ @ @ @ @ @ For each hot spell , they calculated the relative probabilities that a similar event could have occurred with and without human influence .
They found that human activities such as greenhouse gas emissions made the heat waves much more likely to occur .
“ For several of these heat waves we got a human contribution of 100 % , meaning that they could not have occurred without anthropogenic global warming , ” said Laufkötter .
These included the infamous “ Blob ” that lingered off the coast of the Pacific Northwest from 2013 @ @ @ @ @ @ @ along with mass sea life starvation , as well as the intense Southwest Atlantic heat wave in 2017 .
In addition to calculating the relative probabilities , the scientists predicted how much more common such heat waves would be under different future emission scenarios .
Even if an ambitious effort limited total warming to about 1.5-2 degrees Celsius above preindustrial levels , Blob-like heat waves that normally occur once every 100,000 years would come about every decade .
And at 2-3 C of warming , heat waves would happen every decade or even @ @ @ @ @ @ @ ocean might exist in perpetual heat wave conditions , they found .
“ It scares me , to be honest , ” said Laufkötter .
According to her , the ocean ’ s reaction to these heat waves may be the most accurate preview available for what global warming will look like .

Unusually hot zones in the ocean will last longer and occur more often in the coming century.
Christian Fogerty, Contributor
(Inside Science) -- Marine heat waves can wreak havoc on fisheries, coral reefs, kelp forests and other vital ocean ecosystems. In a new paper in the journal Science, climate scientists revealed strong evidence that future marine heat waves will intensify and occur much more frequently as a direct result of anthropogenic climate change.
The scientists, led by postdoctoral researcher Charlotte Laufkötter at the University of Bern in Switzerland, focused on seven well-documented marine heat waves from the past decade. For each hot spell, they calculated the relative probabilities that a similar event could have occurred with and without human influence. They found that human activities such as greenhouse gas emissions made the heat waves much more likely to occur.
“For several of these heat waves we got a human contribution of 100%, meaning that they could not have occurred without anthropogenic global warming,” said Laufkötter. These included the infamous “Blob” that lingered off the coast of the Pacific Northwest from 2013 to 2016 and caused record-setting warm winters along with mass sea life starvation, as well as the intense Southwest Atlantic heat wave in 2017.
In addition to calculating the relative probabilities, the scientists predicted how much more common such heat waves would be under different future emission scenarios. Even if an ambitious effort limited total warming to about 1.5-2 degrees Celsius above preindustrial levels, Blob-like heat waves that normally occur once every 100,000 years would come about every decade. And at 2-3 C of warming, heat waves would happen every decade or even every year. Vast stretches of the ocean might exist in perpetual heat wave conditions, they found.
“It scares me, to be honest,” said Laufkötter. According to her, the ocean’s reaction to these heat waves may be the most accurate preview available for what global warming will look like.


insidescience--2020-10-09--Around 800 Years Ago, Yellowstone's Old Faithful Stopped Erupting

New findings suggest the famous geyser went dormant during a period of severe droughts -- a condition that could recur in a warming world .
( Inside Science ) -- One of the most famously reliable geysers in the world may have taken more than a century off duty during medieval times , new research finds .
Scientists recently recovered mineralized tree pieces dating from around A.D. 1230-1360 from the mound of Old Faithful geyser in Yellowstone National Park , suggesting the geyser stopped erupting long enough for the trees to grow .
`` Old Faithful is likely thousands of @ @ @ @ @ @ @ , a research hydrologist with the U.S. Geological Survey , who is an author on the new paper .
`` We found root crowns high up on the mound , and that means that when the trees grew the Old Faithful mound had about the same structure as it has today . ''
Old Faithful draws throngs of visitors each year who count on it to routinely put on a spectacular , water-spewing show .
The geyser ’ s reputation for reliability goes back at least 150 years , when members of an @ @ @ @ @ @ @ Washburn and Montana politician and businessman Nathaniel Langford first dubbed it Old Faithful .
The geologist Ferdinand Hayden , who led a subsequent scientific expedition in 1871 , wrote of Old Faithful : `` It has been called the Guardian of the Valley .
It is so regular in its operations and they occur so frequently that it has afforded unusual facilities for observation . ''
Yet many of Old Faithful ’ s visitors may not realize the precise balance of heat and water required to keep the geyser regularly ejecting a fountain @ @ @ @ @ @ @ intricate underground plumbing .
`` The way I try to explain it is that if you have a lot of water compared to the amount of heat , you end up with a hot spring .
And if you have a lot of heat compared to water , you end up with a fumarole , which is a hissing steam vent .
In the middle , you have this delicate balance between the amount of heat and the amount of water , and the geyser will only erupt when it gets the required @ @ @ @ @ @ @ said Susan Kieffer , a geologist who started studying Old Faithful in the 1970s and was one of a group of researchers who in 1991 lowered a camera into the geyser ’ s vent to see what was going on .
When Old Faithful went dormant hundreds of years ago , it was probably the water part of the equation that was thrown out of whack .
The geyser stopped erupting toward the end of the so-called Medieval Climate Anomaly , a time when many locations around the world experienced prolonged periods of @ @ @ @ @ @ @ ’ s the time when we have things like grapes growing in Northern England and a loss of sea ice that allowed people to discover Greenland , '' said Cathy Whitlock , a paleoclimatologist at Montana State University in Bozeman .
`` We know in Yellowstone it was both warmer and drier .
The upper tree line was higher up the slopes and there is evidence of more fires during that period . ''
Stream flows were also lower , she added .
Extreme droughts in the region lasted for decades .
Hurwitz @ @ @ @ @ @ @ the mineralized tree remains they recovered from Old Faithful with a record of stream flow in the Yellowstone area reconstructed from tree-ring data .
They found that the ages of the trees coincided with a series of severe droughts .
Researchers have also found that earthquake-caused changes in the ground can alter geysers ’ eruption intervals ( and are likely one of the main reasons that Old Faithful now erupts on average every 94 minutes , compared to intervals of around 60-65 minutes in the 1950s . )
However , Hurwitz and his @ @ @ @ @ @ @ activity around the time of Old Faithful ’ s dormant period , so the researchers concluded the dry climate probably caused the hiatus .
These days , the Yellowstone region is again experiencing droughts , this time most likely linked to human-caused global warming .
In 2008 , Hurwitz and his colleagues published a paper showing that years with lower precipitation at the end of the 20th century and beginning of the 21st century had likely added a minute or two to Old Faithful ’ s eruption cycle .
It ’ s possible @ @ @ @ @ @ @ the climate continues to dry .
The new research `` ties the behavior of Old Faithful to climate projections which should be of great interest to the Park managers , '' said Kieffer in an email .
`` It is a careful piece of work that looks intriguing and important . ''
A paper detailing the new findings was published online yesterday in the journal Geophysical Research Letters .

New findings suggest the famous geyser went dormant during a period of severe droughts -- a condition that could recur in a warming world.
Catherine Meyers, Editor
(Inside Science) -- One of the most famously reliable geysers in the world may have taken more than a century off duty during medieval times, new research finds. Scientists recently recovered mineralized tree pieces dating from around A.D. 1230-1360 from the mound of Old Faithful geyser in Yellowstone National Park, suggesting the geyser stopped erupting long enough for the trees to grow.
"Old Faithful is likely thousands of years old," said Shaul Hurwitz, a research hydrologist with the U.S. Geological Survey, who is an author on the new paper. "We found root crowns high up on the mound, and that means that when the trees grew the Old Faithful mound had about the same structure as it has today."
Image Old Faithful currently erupts on average every 94 minutes. Media credits Shaul Hurwitz/USGS
Old Faithful draws throngs of visitors each year who count on it to routinely put on a spectacular, water-spewing show. The geyser’s reputation for reliability goes back at least 150 years, when members of an expedition led by Surveyor-General of Montana Henry Washburn and Montana politician and businessman Nathaniel Langford first dubbed it Old Faithful. The geologist Ferdinand Hayden, who led a subsequent scientific expedition in 1871, wrote of Old Faithful: "It has been called the Guardian of the Valley. It is so regular in its operations and they occur so frequently that it has afforded unusual facilities for observation."
Yet many of Old Faithful’s visitors may not realize the precise balance of heat and water required to keep the geyser regularly ejecting a fountain of hot water and steam from its intricate underground plumbing.
"The way I try to explain it is that if you have a lot of water compared to the amount of heat, you end up with a hot spring. And if you have a lot of heat compared to water, you end up with a fumarole, which is a hissing steam vent. In the middle, you have this delicate balance between the amount of heat and the amount of water, and the geyser will only erupt when it gets the required amount of each of those," said Susan Kieffer, a geologist who started studying Old Faithful in the 1970s and was one of a group of researchers who in 1991 lowered a camera into the geyser’s vent to see what was going on.
When Old Faithful went dormant hundreds of years ago, it was probably the water part of the equation that was thrown out of whack. The geyser stopped erupting toward the end of the so-called Medieval Climate Anomaly, a time when many locations around the world experienced prolonged periods of warm, dry weather.
"It’s the time when we have things like grapes growing in Northern England and a loss of sea ice that allowed people to discover Greenland," said Cathy Whitlock, a paleoclimatologist at Montana State University in Bozeman. "We know in Yellowstone it was both warmer and drier. The upper tree line was higher up the slopes and there is evidence of more fires during that period." Stream flows were also lower, she added. Extreme droughts in the region lasted for decades.
Image One of the wood samples found on Old Faithful. Media credits USGS
Hurwitz and his colleagues compared the ages of the mineralized tree remains they recovered from Old Faithful with a record of stream flow in the Yellowstone area reconstructed from tree-ring data. They found that the ages of the trees coincided with a series of severe droughts.
Researchers have also found that earthquake-caused changes in the ground can alter geysers’ eruption intervals (and are likely one of the main reasons that Old Faithful now erupts on average every 94 minutes, compared to intervals of around 60-65 minutes in the 1950s.) However, Hurwitz and his colleagues found no evidence of significant earthquake activity around the time of Old Faithful’s dormant period, so the researchers concluded the dry climate probably caused the hiatus.
These days, the Yellowstone region is again experiencing droughts, this time most likely linked to human-caused global warming. In 2008, Hurwitz and his colleagues published a paper showing that years with lower precipitation at the end of the 20th century and beginning of the 21st century had likely added a minute or two to Old Faithful’s eruption cycle. It’s possible the geyser could shut down completely if the climate continues to dry.
The new research "ties the behavior of Old Faithful to climate projections which should be of great interest to the Park managers," said Kieffer in an email. "It is a careful piece of work that looks intriguing and important."
A paper detailing the new findings was published online yesterday in the journal Geophysical Research Letters.


insidescience--2020-10-16--Meter-long Crystals May Grow in Just a Few Days

Meter-long Crystals May Grow in Just a Few Days Research suggests crystals form in cooling magma at an astonishingly rapid rate .
( Inside Science ) -- When it comes to geologic events that happen fast , you might think of an earthquake or an erupting volcano .
But crystal growth can also happen at a surprisingly rapid pace , according to new research .
`` I have to admit , I never expected the rates to be as fast as they were , '' said Patrick Phelps , a doctoral student in geology at Rice University in Houston , @ @ @ @ @ @ @ this month in the journal Nature Communications showing that large crystals , more than a meter in length , could grow in a matter of days .
The researchers calculated the growth rate from smaller crystals , but meter-long crystals have been found in similar types of rock .
The project began years ago when Phelps was considering doctoral programs .
He fell into a conversation with geologist Cin-Ty Lee while visiting Rice University .
Lee posed a question to the young student : Have you ever thought much about how fast crystals @ @ @ @ @ @ @ big ones like what you might see in the pages of National Geographic magazine ?
`` In my head , I was thinking it must take 10,000 or 100,000 years , '' Phelps recalled .
And Lee said : What if it wasn ’ t that long at all ?
Phelps dove headfirst into research on igneous rocks called pegmatites , which are formed underground by cooling magma and have interlocking crystals that are occasionally very large .
He was able to get some samples from a mine in southern California .
He @ @ @ @ @ @ @ at the crystal .
The electrons get absorbed by defects in the crystal lattice , releasing visible light as they decay .
`` It ’ s really cool to see the colors change , '' said Phelps .
`` You go from this clear quartz to this weird orange and purple thing -- those colors are caused by defects . ''
The colorful map of the crystal then guided the researchers on where to look for trace elements .
They used another technique called laser ablation to understand the arrangement of the trace @ @ @ @ @ @ @ .
One intriguing finding : The crystal doesn ’ t grow at the same rate everywhere .
The middle seems to grow more slowly , and the researchers modeled an uptick at the edges , Phelps explained .
The current study focused on quartz crystals , which are abundant and important , but Phelps hopes to investigate other types of minerals in the future .
For example , understanding crystal growth could help researchers predict where to look for lithium , a mineral that is vital to modern life due to its use @ @ @

Research suggests crystals form in cooling magma at an astonishingly rapid rate.
Katharine Gammon, Contributor
(Inside Science) -- When it comes to geologic events that happen fast, you might think of an earthquake or an erupting volcano. But crystal growth can also happen at a surprisingly rapid pace, according to new research.
"I have to admit, I never expected the rates to be as fast as they were," said Patrick Phelps, a doctoral student in geology at Rice University in Houston, Texas. Phelps co-authored a paper published this month in the journal Nature Communications showing that large crystals, more than a meter in length, could grow in a matter of days. The researchers calculated the growth rate from smaller crystals, but meter-long crystals have been found in similar types of rock.
The project began years ago when Phelps was considering doctoral programs. He fell into a conversation with geologist Cin-Ty Lee while visiting Rice University. Lee posed a question to the young student: Have you ever thought much about how fast crystals grow? You know, the really big ones like what you might see in the pages of National Geographic magazine?
"In my head, I was thinking it must take 10,000 or 100,000 years," Phelps recalled. And Lee said: What if it wasn’t that long at all?
Phelps dove headfirst into research on igneous rocks called pegmatites, which are formed underground by cooling magma and have interlocking crystals that are occasionally very large. He was able to get some samples from a mine in southern California.
He used cathodoluminescence, which essentially shoots electrons at the crystal. The electrons get absorbed by defects in the crystal lattice, releasing visible light as they decay. "It’s really cool to see the colors change," said Phelps. "You go from this clear quartz to this weird orange and purple thing -- those colors are caused by defects."
The colorful map of the crystal then guided the researchers on where to look for trace elements. They used another technique called laser ablation to understand the arrangement of the trace elements, which revealed the growth rate. One intriguing finding: The crystal doesn’t grow at the same rate everywhere. The middle seems to grow more slowly, and the researchers modeled an uptick at the edges, Phelps explained.
The current study focused on quartz crystals, which are abundant and important, but Phelps hopes to investigate other types of minerals in the future. For example, understanding crystal growth could help researchers predict where to look for lithium, a mineral that is vital to modern life due to its use in batteries.