Unique Fragment From Earth’s Formation Returns After Billions Of Years In Cold Storage

In a paper to be published today in the journal Science Advances, lead author Karen Meech of the University of Hawai`i’s Institute for Astronomy and her colleagues conclude that C/2014 S3 (PANSTARRS) formed in the inner Solar System at the same time as the Earth itself, but was ejected at a very early stage.

object

Their observations indicate that it is an ancient rocky body, rather than a contemporary asteroid that strayed out. As such, it is one of the potential building blocks of the rocky planets, such as the Earth, that was expelled from the inner Solar System and preserved in the deep freeze of the Oort Cloud for billions of years.

Karen Meech explains the unexpected observation: “We already knew of many asteroids, but they have all been baked by billions of years near the Sun. This one is the first uncooked asteroid we could observe: it has been preserved in the best freezer there is.”

C/2014 S3 (PANSTARRS) was originally identified by the Pan-STARRS1 telescope as a weakly active comet a little over twice as far from the Sun as the Earth. Its current long orbital period (around 860 years) suggests that its source is in the Oort Cloud, and it was nudged comparatively recently into an orbit that brings it closer to the Sun.

The team immediately noticed that C/2014 S3 (PANSTARRS) was unusual, as it does not have the characteristic tail that most long-period comets have when they approach so close to the Sun. As a result, it has been dubbed a Manx comet, after the [tailless cat]. Within weeks of its discovery, the team obtained spectra of the very faint object with ESO’s Very Large Telescope in Chile.

Careful study of the light reflected by C/2014 S3 (PANSTARRS) indicates that it is typical of asteroids known as S-type, which are usually found in the inner asteroid main belt. It does not look like a typical comet, which are believed to form in the outer Solar System and are icy, rather than rocky. It appears that the material has undergone very little processing, indicating that it has been deep frozen for a very long time. The very weak comet-like activity associated with C/2014 S3 (PANSTARRS), which is consistent with the sublimation of water ice, is about a million times lower than active long-period comets at a similar distance from the Sun.

The authors conclude that this object is probably made of fresh inner Solar System material that has been stored in the Oort Cloud and is now making its way back into the inner Solar System.

A number of theoretical models are able to reproduce much of the structure we see in the Solar System. An important difference between these models is what they predict about the objects that make up the Oort Cloud. Different models predict significantly different ratios of icy to rocky objects. This first discovery of a rocky object from the Oort Cloud is therefore an important test of the different predictions of the models. The authors estimate that observations of 50-100 of these Manx comets are needed to distinguish between the current models, opening up another rich vein in the study of the origins of the Solar System.

Co-author Olivier Hainaut (ESO, Garching, Germany), concludes: “We’ve found the first rocky comet, and we are looking for others. Depending how many we find, we will know whether the giant planets danced across the Solar System when they were young, or if they grew up quietly without moving much.”

* The Oort cloud is a huge region surrounding the Sun like a giant, thick soap bubble. It is estimated that it contains trillions of tiny icy bodies. Occasionally, one of these bodies gets nudged and falls into the inner Solar System, where the heat of the sun turns it into a comet. These icy bodies are thought to have been ejected from the region of the giant planets as these were forming, in the early days of the Solar System.

This research was presented in a paper entitled “Inner Solar System Material Discovered in the Oort Cloud,” by Karen Meech et al., in the journal Science Advances.

The team is composed of Karen J. Meech (Institute for Astronomy, University of Hawai`i, USA), Bin Yang (ESO, Santiago, Chile), Jan Kleyna (Institute for Astronomy, University of Hawai`i, USA), Olivier R. Hainaut (ESO, Garching, Germany), Svetlana Berdyugina (Institute for Astronomy, University of Hawai’i, USA; Kiepenheuer Institut für Sonnenphysik, Freiburg, Germany), Jacqueline V. Keane (Institute for Astronomy, University of Hawai`i, USA), Marco Micheli (ESA, Frascati, Italy), Alessandro Morbidelli (Laboratoire Lagrange/Observatoire de la Côte d’Azur/CNRS/Université Nice Sophia Antipolis, France) and Richard J. Wainscoat (Institute for Astronomy, University of Hawai`i, USA).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky.”

BREAKING NEWS: A Dramatic Galactic Explosion Arrived at Earth in 2012

A dramatic explosion occurred from a galaxy known as PKS B1424-418. Light from this blast began arriving at Earth in 2012. On Dec. 4, 2012, the IceCube Neutrino Observatory at the South Pole detected an event known as Big Bird – a neutrino gamma ray blazer with an energy exceeding 2 quadrillion electron volts (PeV). Now, an international team of astronomers, led by Matthias Kadler, professor for astrophysics at the University of Würzburg, has published their results in the scientific journal Nature Physics.

dec 2012 blazer hits milky way and earth

Starting in the summer of 2012, NASA’s Fermi satellite witnessed a dramatic brightening of PKS B1424-418, an active galaxy classified as a gamma-ray blazar. An active galaxy is an otherwise typical galaxy with a compact and unusually bright core. The excess luminosity of the central region is produced by matter falling toward a supermassive black hole weighing millions of times the mass of our Sun. As it approaches the black hole, some of the material becomes channeled into particle jets moving outward in opposite directions at nearly the speed of light. In blazars one of these jets happens to point almost directly toward Earth.

During the year-long outburst, PKS B1424-418 shone between 15 and 30 times brighter in gamma rays than its average before the eruption. The blazar is located within the Big Bird source region, but then so are many other active galaxies detected by Fermi.

milky-way-solar-system

The scientists searching for the neutrino source then turned to data from a long-term observing program named TANAMI. Since 2007, TANAMI has routinely monitored nearly 100 active galaxies in the southern sky, including many flaring sources detected by Fermi. Three radio observations between 2011 and 2013 cover the period of the Fermi outburst. They reveal that the core of the galaxy’s jet had been brightening by about four times. No other galaxy observed by TANAMI over the life of the program has exhibited such a dramatic change.

“Within their jets, blazars are capable of accelerating protons to relativistic energies. Interactions of these protons with light in the central regions of the blazar can create pions. When these pions decay, both gamma rays and neutrinos are produced,” explains Karl Mannheim, a coauthor of the study and astronomy professor in Würzburg, Germany. “We combed through the field where Big Bird must have originated looking for astrophysical objects capable of producing high-energy particles and light,” adds coauthor Felicia Kraub from the University of Erlangen-Nürnberg in Germany.

tanami_sky_world10

In published report, the team suggests the PKS B1424-418 outburst and Big Bird are linked, calculating only a 5-percent probability the two events occurred by chance alone. Using data from Fermi, NASA’s Swift and WISE satellites, the LBA and other facilities, the researchers determined how the energy of the eruption was distributed across the electromagnetic spectrum and showed that it was sufficiently powerful to produce a neutrino at PeV energies.

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JUST IN: Scientists Beginning to Identify Signs That Galactic Cycles are Analogous with Sun-Earth’s Circumvolution

A Description of Extraterrestrial Galactic Obedience and Disobedience evolving within a tangled yet symmetrical display of what to some would appear to be as though disjointed and without direction. HOWEVER, when a person as myself, having watched closely for over 16 years and having intimately documented and published my research of the Sun-Earth connection, I found myself in a most optimized position to systematize newly disclosed research.

equation-1998

Equation:
Sunspots → Solar Flares (charged particles) → Magnetic Field Shift → Shifting Ocean and Jet Stream Currents → Extreme Weather and Human Disruption (mitch battros 1998).

Such findings include new discoveries of the inner-workings of our galaxy ‘Milky Way’ and its interaction with or solar system and of course our home planet Earth. Near mind-blowing insights into the mechanics of celestial events such as supernovas, gamma ray burst, pulsars, galactic cosmic rays, and closer to home – solar flares and coronal mass ejections.

milky-way-solar-system

New Equation:
Increase Charged Particles and Decreased Magnetic Field → Increase Outer Core Convection → Increase of Mantle Plumes → Increase in Earthquake and Volcanoes → Cools Mantle and Outer Core → Return of Outer Core Convection (Mitch Battros – July 2012).

New findings released yesterday described a large supernova event occurred in a galaxy near our own Milky Way named M74. The exploding star was 200 times larger than our Sun. The sudden blast hurled material outward from the star at a speed of 10,000 kilometers a second. That’s equivalent to 36 million kilometers an hour or 22.4 million miles an hour.

The massive explosion was one of the closest to Earth in recent years, visible as a point of light in the night sky starting July 24, 2013, said Robert Kehoe, SMU physics professor, who leads SMU’s astrophysics team.

supernovam74

“There are so many characteristics we can derive from the early data,” said astrophysicist Govinda Dhungana of Southern Methodist University. “This was a big massive star, burning tremendous fuel. When it finally reached a point its core couldn’t support the gravitational pull inward, suddenly it collapsed and then exploded.”

fatblackhole-m

The star’s original mass was about 15 times that of our Sun, Dhungana said. Its temperature was a hot 12,000 Kelvin (approximately 22,000 degrees Fahrenheit) on the tenth day after the explosion, steadily cooling until it reached 4,500 Kelvin after 50 days. The Sun’s surface is 5,800 Kelvin, while the Earth’s core is estimated to be about 6,000 Kelvin.

The new measurements are published online here in the May 2016 issue of The Astrophysical Journal, “Extensive spectroscopy and photometry of the Type IIP Supernova 2013j.”

 

Possible Extragalactic Source Of High-Energy Neutrinos

Nearly 10 billion years ago in a galaxy known as PKS B1424-418, a dramatic explosion occurred. Light from this blast began arriving at Earth in 2012. Now, an international team of astronomers, led by Prof. Matthias Kadler, professor for astrophysics at the university of Würzburg, and including other scientists from the new research cluster for astronomy and astroparticle physics at the universities of Würzburg and Erlangen-Nürnberg, have shown that a record-breaking neutrino seen around the same time likely was born in the same event. The results are published in Nature Physics.

Neutrinos are the fastest, lightest, most unsociable and least understood fundamental particles, and scientists are just now capable of detecting high-energy ones arriving from deep space. The present work provides the first plausible association between a single extragalactic object and one of these cosmic neutrinos.

blazar

Although neutrinos far outnumber all the atoms in the universe, they rarely interact with matter, which makes detecting them quite a challenge. But this same property lets neutrinos make a fast exit from places where light cannot easily escape such as the core of a collapsing star and zip across the universe almost completely unimpeded. Neutrinos can provide information about processes and environments that simply aren’t available through a study of light alone.

Recently, the IceCube Neutrino Observatory at the South Pole found first evidence for a flux of extraterrestrial neutrinos, which was named the Physics World breakthrough of the year 2013. To date, the science team of IceCube Neutrino has announced about a hundred very high-energy neutrinos and nicknamed the most extreme events after characters on the children’s TV series “Sesame Street.” On Dec. 4, 2012, IceCube detected an event known as Big Bird, a neutrino with an energy exceeding 2 quadrillion electron volts (PeV). To put that in perspective, it’s more than a million million times greater than the energy of a dental X-ray packed into a single particle thought to possess less than a millionth the mass of an electron. Big Bird was the highest-energy neutrino ever detected at the time and still ranks second.

Where did it come from? The best IceCube position only narrowed the source to a patch of the southern sky about 32 degrees across, equivalent to the apparent size of 64 full moons. “It’s like a crime scene investigation,” says lead author Matthias Kadler, a professor of astrophysics at the University of Würzburg in Germany, “The case involves an explosion, a suspect, and various pieces of circumstantial evidence.”

Starting in the summer of 2012, NASA’s Fermi satellite witnessed a dramatic brightening of PKS B1424-418, an active galaxy classified as a gamma-ray blazar. An active galaxy is an otherwise typical galaxy with a compact and unusually bright core. The excess luminosity of the central region is produced by matter falling toward a supermassive black hole weighing millions of times the mass of our sun. As it approaches the black hole, some of the material becomes channeled into particle jets moving outward in opposite directions at nearly the speed of light. In blazars one of these jets happens to point almost directly toward Earth.

During the year-long outburst, PKS B1424-418 shone between 15 and 30 times brighter in gamma rays than its average before the eruption. The blazar is located within the Big Bird source region, but then so are many other active galaxies detected by Fermi.

The scientists searching for the neutrino source then turned to data from a long-term observing program named TANAMI. Since 2007, TANAMI has routinely monitored nearly 100 active galaxies in the southern sky, including many flaring sources detected by Fermi. Three radio observations between 2011 and 2013 cover the period of the Fermi outburst. They reveal that the core of the galaxy’s jet had been brightening by about four times. No other galaxy observed by TANAMI over the life of the program has exhibited such a dramatic change.

“Within their jets, blazars are capable of accelerating protons to relativistic energies. Interactions of these protons with light in the central regions of the blazar can create pions. When these pions decay, both gamma rays and neutrinos are produced,” explains Karl Mannheim, a coauthor of the study and astronomy professor in Würzburg, Germany. “We combed through the field where Big Bird must have originated looking for astrophysical objects capable of producing high-energy particles and light,” adds coauthor Felicia Krauß, a doctoral student at the University of Erlangen-Nürnberg in Germany. “There was a moment of wonder and awe when we realized that the most dramatic outburst we had ever seen in a blazar happened in just the right place at just the right time.”

In a paper published Monday, April 18, in Nature Physics, the team suggests the PKS B1424-418 outburst and Big Bird are linked, calculating only a 5-percent probability the two events occurred by chance alone. Using data from Fermi, NASA’s Swift and WISE satellites, the LBA and other facilities, the researchers determined how the energy of the eruption was distributed across the electromagnetic spectrum and showed that it was sufficiently powerful to produce a neutrino at PeV energies.

“Taking into account all of the observations, the blazar seems to have had means, motive and opportunity to fire off the Big Bird neutrino, which makes it our prime suspect,” explains Matthias Kadler.

Francis Halzen, the principal investigator of IceCube at the University of Wisconsin-Madison, and not involved in this study, thinks the result is an exciting hint of things to come. “IceCube is about to send out real-time alerts when it records a neutrino that can be localized to an area a little more than half a degree across, or slightly larger than the apparent size of a full moon,” he concludes. “We’re slowly opening a neutrino window onto the cosmos.”

But this study also demonstrates the vital importance of classical astronomical observations in an era when new detection methods like neutrino observatories and gravitational-wave detectors open new but unknown skies.

Geochemical Detectives Use Lab Mimicry To Look Back In Time

New work from a research team led by Carnegie’s Anat Shahar contains some unexpected findings about iron chemistry under high-pressure conditions, such as those likely found in the Earth’s core, where iron predominates and creates our planet’s life-shielding magnetic field. Their results, published in Science, could shed light on Earth’s early days when the core was formed through a process called differentiation–when the denser materials, like iron, sunk inward toward the center, creating the layered composition the planet has today.

earth

Earth formed from accreted matter surrounding the young Sun. Over time, the iron in this early planetary material moved inward, separating from the surrounding silicate. This process created the planet’s iron core and silicate upper mantle. But much about this how this differentiation process occurred is still poorly understood, due to the technological impossibility of taking samples from the Earth’s core to see which compounds exist there.

Seismic data show that in addition to iron, there are “lighter” elements present in the core, but which elements and in what concentrations they exist has been a matter of great debate. This is because as the iron moved inward toward the core, it interacted with various lighter elements to form different alloyed compounds, which were then carried along with the iron into the planet’s depths.

Which elements iron bonded with during this time would have been determined by the surrounding conditions, including pressure and temperature. As a result, working backward and determining which iron alloy compounds were created during differentiation could tell scientists about the conditions on early Earth and about the planet’s geochemical evolution.

The team–including Carnegie’s Jinfu Shu and Yuming Xiao–decided to investigate this subject by researching how pressures mimicking the Earth’s core would affect the composition of iron isotopes in various alloys of iron and light elements. Isotopes are versions of an element where the number of neutrons differs from the number of protons. (Each element contains a unique number of protons.)

Because of this accounting difference, isotopes’ masses are not the same, which can sometimes cause small variations in how different isotopes of the same element are partitioned in, or are “picked up” by, either silicate or iron metal. Some isotopes are preferred by certain reactions, which results in an imbalance in the proportion of each isotope incorporated into the end products of these reactions–a process that can leave behind trace isotopic signatures in rocks. This phenomenon is called isotope fractionation and is crucial to the team’s research.

Before now, pressure was not considered a critical variable affecting isotope fractionation. But Shahar and her team’s research demonstrated that for iron, extreme pressure conditions do affect isotope fractionation.

More importantly, the team discovered that due to this high-pressure fractionation, reactions between iron and two of the light elements often considered likely to be present in the core–hydrogen and carbon–would have left behind an isotopic signature in the mantle silicate as they reacted with iron and sunk to the core. But this isotopic signature has not been found in samples of mantle rock, so scientists can exclude them from the list of potential light elements in the core.

Oxygen, on the other hand, would not have left an isotopic signature behind in the mantle, so it is still on the table. Likewise, other potential core light elements still need to be investigated, including silicon and sulfur.

“What does this mean? It means we are gaining a better understanding of our planet’s chemical and physical history,” Shahar explained. “Although Earth is our home, there is still so much about its interior that we don’t understand. But evidence that extreme pressures affect how isotopes partition, in ways that we can see traces of in rock samples, is a huge step forward in learning about our planet’s geochemical evolution.”

Cassini Explores A Methane Sea On Titan

Of the hundreds of moons in our solar system, Titan is the only one with a dense atmosphere and large liquid reservoirs on its surface, making it in some ways more like a terrestrial planet.

titan

Both Earth and Titan have nitrogen-dominated atmospheres — over 95 percent nitrogen in Titan’s case. However, unlike Earth, Titan has very little oxygen; the rest of the atmosphere is mostly methane and trace amounts of other gases, including ethane. And at the frigid temperatures found at Saturn’s great distance from the Sun, the methane and ethane can exist on the surface in liquid form.

For this reason, scientists had long speculated about the possible existence of hydrocarbon lakes and seas on Titan, and data from the NASA/ESA Cassini-Huygens mission does not disappoint. Since arriving in the Saturn system in 2004, the Cassini spacecraft has revealed that more than 620,000 square miles (1.6 million square kilometers) of Titan’s surface — almost two percent of the total — are covered in liquid.

There are three large seas, all located close to the moon’s north pole, surrounded by numerous of smaller lakes in the northern hemisphere. Just one large lake has been found in the southern hemisphere.

The exact composition of these liquid reservoirs remained elusive until 2014, when the Cassini radar instrument was first used to show that Ligeia Mare, the second largest sea on Titan and similar in size to Lake Huron and Lake Michigan combined, is methane-rich. A new study published in the Journal of Geophysical Research: Planets, which used the radar instrument in a different mode, independently confirms this result.

“Before Cassini, we expected to find that Ligeia Mare would be mostly made up of ethane, which is produced in abundance in the atmosphere when sunlight breaks methane molecules apart. Instead, this sea is predominantly made of pure methane,” said Alice Le Gall, a Cassini radar team associate at the French research laboratory LATMOS, Paris, and lead author of the new study.

The new study is based on data collected with Cassini’s radar instrument during flybys of Titan between 2007 and 2015.

A number of possible explanations could account for the sea’s methane composition, according to Le Gall. “Either Ligeia Mare is replenished by fresh methane rainfall, or something is removing ethane from it. It is possible that the ethane ends up in the undersea crust, or that it somehow flows into the adjacent sea, Kraken Mare, but that will require further investigation.”

In their research, the scientists combined several radar observations of heat given off by Ligeia Mare. They also used data from a 2013 experiment that bounced radio signals off Ligeia. The results of that experiment were presented in a 2014 paper led by radar team associate Marco Mastrogiuseppe at Cornell University, Ithaca, New York, who also contributed to the current study.

During the 2013 experiment, the radar instrument detected echoes from the seafloor and inferred the depth of Ligeia Mare along Cassini’s track over Ligeia Mare — the first-ever detection of the bottom of an extraterrestrial sea. The scientists were surprised to find depths in the sea as great as 525 feet (160 meters) at the deepest point along the radar track.

Le Gall and her colleagues used the depth-sounding information to separate the contributions made to the sea’s observed temperature by the liquid sea and the seabed, which provided insights into their respective compositions.

“We found that the seabed of Ligeia Mare is likely covered by a sludge layer of organic-rich compounds,” adds Le Gall.

In the atmosphere of Titan, nitrogen and methane react to produce a wide variety of organic materials. Scientists believe the heaviest materials fall to the surface. Le Gall and colleagues think that when these compounds reach the sea, either by directly falling from the air, via rain or through Titan’s rivers, some are dissolved in the liquid methane. The insoluble compounds, such as nitriles and benzene, sink to the sea floor.

The study also found that the shoreline around Ligeia Mare may be porous and flooded with liquid hydrocarbons. The data span a period running from local winter to spring, and the scientists expected that — like the seaside on Earth — the surrounding solid terrains would warm more rapidly than the sea.

However, Cassini’s measurements did not show any significant difference between the sea’s temperature and that of the shore over this period. This suggests that the terrains surrounding the lakes and seas are wet with liquid hydrocarbons, which would make them warm up and cool down much like the sea itself.

“It’s a marvelous feat of exploration that we’re doing extraterrestrial oceanography on an alien moon,” said Steve Wall, deputy lead of the Cassini radar team at NASA’s Jet Propulsion Laboratory in Pasadena, California. “Titan just won’t stop surprising us.”

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the US and several European countries.

Rainwater May Play An Important Role In Process That Triggers Earthquakes

Rainwater may play an important role in the process that triggers earthquakes, according to new research.

alps

Researchers from the University of Southampton, GNS Science (New Zealand), the University of Otago, and GFZ Potsdam (Germany), identified the sources and fluxes of the geothermal fluids and mineral veins from the Southern Alps of New Zealand where the Pacific and Australian Plates collide along the Alpine Fault.

From careful chemical analyses, they discovered that fluids originating from the mantle, the layer below Earth’s crust, and fluids derived from rainwater, are channelled up the Alpine Fault.

By calculating how much fluid is flowing through the fault zone at depth, the researchers showed for the first time that enough rainwater is present to promote earthquake rupture on this major plate boundary fault.

Lead researcher Dr Catriona Menzies, from Ocean and Earth Science at the University of Southampton, said: “Large, continental-scale faults can cause catastrophic earthquakes, but the trigger mechanisms for major seismic events are not well known. Geologists have long suspected that deep groundwaters may be important for the initiation of earthquakes as these fluids can weaken the fault zones by increasing pressures or through chemical reactions.

“Fluids are important in controlling the evolution of faults between earthquake ruptures. Chemical reactions may alter the strength and permeability of rocks, and if enough fluid is present at sufficiently high pressures they may aid earthquake rupture by ‘pumping up’ the fault zone.”

The Alpine Fault is a major strike-slip fault, like the San Andreas, that fails in very large (Magnitude 8+) earthquakes around every 300 years. It last ruptured in 1717 AD and consequently it is under intense scientific scrutiny because it is a rare example of a major fault that is late in the strain-build up before rupture.

Dr Menzies said: “We show that the Alpine Fault acts as a barrier to lateral fluid flow from the high mountains of the Southern Alps towards the Tasman Sea in the west. However, the presence of mantle-derived fluids indicates that the fault also acts as a channel for fluids, from more than 35 km depth, to ascend to the surface.

“As well as mantle derived fluids, our calculations indicate that 0.02-0.05 per cent of surface rainfall reaches around six kilometres depth but this is enough to overwhelm contributions from the mantle and fluids generated during mountain-building by metamorphic reactions in hot rocks. This rainwater is then focused onto the fault, forced by the hydraulic head of the high mountains above and the sub-vertical fluid flow barrier of the Alpine Fault.”

Funding for this research, published in Earth and Planetary Science Letters, was provided by the Natural Environmental Research Council (NERC), Deutsche Forschungsgemeinschaft, and GNS Science (New Zealand).