geological

the brutal ESA image that summarizes the geological violence of Mars in a single photo

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The noticeable changes in the mars landscape They are very slow. It is estimated that they may take up to millions of years to occur, as it is considered a fairly static planet in that regard. However, scientists from the European Space Agency (ESA) have detected a change that occurred much more quickly. So much so that humans of the same generation have been conscious. From Viking to Mars Express. The High Resolution Stereoscopic Camera (HRSC) The Mars Express has taken some images that have caught the attention of the ESA scientists in charge of analyzing them. In them you can see a large area covered in ashes. These ashes already appeared in other photos taken by NASA’s Viking orbiters in 1976. However, there were much fewer of them then. It is surprising how much they have proliferated in just 50 years. volcanic origin. The origin of these ashes is quite clear. The volcanic material is known to be rich in ‘mafic’ minerals, which form at high temperatures. Olivine and pyroxene are two good examples. These minerals have a dark appearance, very similar to the ashes that appear in the photos. Therefore, it must have a volcanic origin. In addition, Mars is characterized by having great volcanic activity and by hosting the largest volcano in the Solar System: Olympic Mons. All clues lead to the volcanic origin. The wind spread or uncovered them. What is not so clear is how so many ashes have appeared in such a short time. ESA researchers believe it must be because of the wind. It may be that the Martian winds moved them, spreading them over a wider space, or that they uncovered them. Perhaps they were already there, but the wind moved the ocher dust characteristic of the surface of Mars that would be covering them. Comparison of Viking (left) and Mars Express (right) images A crater among the ashes. Something curious about the photo is that in it you can see many signs of the changes that the Martian surface has experienced over time. On the one hand, we see the aforementioned ashes. And, on the other, the 15 kilometer wide crater that appears in the photo between them. This is surrounded by a striking ring of apparently lighter material, known as an ‘ejector blanket’. It is a structure that is formed from the material thrown by the impact that formed the crater itself. In the photo you can also see some wavy lines inside the crater that mark where the icy material known to be under Mars has been spreading. Changes and more changes. This photograph, which in turn is located in an impact basin called Utopia Planitia, is the living image of how the Martian surface has been modified by impacts, volcanoes and ice that tries to escape between the cracks. Now, at least, we know that not all of these changes are as slow as we thought. Some occur in the blink of a spatial eye. Images | THAT In Xataka | In 2011, a collector bought a meteorite in Morocco. It has turned out to be direct evidence of thermal water on Mars

Most complete geological map reveals billions of years of impacts and volcanism

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We have been talking for years not about landing, but about colonize Mars (above all, Elon Musk), but with Artemis II making history and the Orion ship just splashed down After the first manned mission to the Moon in more than 50 years, the old moon has returned to the forefront. Four astronauts have just photograph it up close and leave us with our mouths open. But the Moon is much more than a satellite full of craters: each of those craters tells a story of billions of years. At this moment when our satellite has hit us again, we rescue geological cartography most complete overview ever published. It is the unified geological map of the moonprepared in 2020 by the United States Geological Survey combining data from the lunar reconnaissance orbiter missions (LRO) from NASA and Kaguya from the Japanese Space Agency. The good thing is that although you can see a general sample, you can also download it to have a greater level of detail, since it is at a scale of 1:5,000,000 and derived from six digitized geological maps. Visually, this world map draws attention both for the number of craters and for the shades chosen to color it. The choice of color is not casual or ornamental, but rather each color represents a type of terrain with a specific age and origin. So, at a glance you know whether you’re looking at an ancient lava plain, a recent crater, or the original crust from 4 billion years ago. Without the colors, everything would be a gray mass of craters impossible to distinguish. The moon is full of secrets and this map provides information in abundance to discover them. The unified geographic map of the moon Fragment of the unified geological map of the Moon, scale 1:5M. Via: USGS The moon has five geological eras: Pre-Nectarian, Nectaric, Imbrian, Eratosthenic and Copernican, which range from 4,000 million years ago to today. How to differentiate them on the map? Because they go from purple and orange for the oldest to green and pink for the youngest. All that is seen is the fossilized record of its turbulent youth because it has been “geologically dead” for almost 3,000 million years, but it had a turbulent past as evidenced by its orography. The moon offers a striking visual dichotomy between the highlands (in reddish tones and saturated with craters) and the seas, which are the large dark spots. Of course, they don’t have any water. They are actually basaltic lava plains that filled huge impact basins about 3,000-4,000 million years ago. It is, in short, what we see from Earth. The clear, cratered areas constitute the original crust and are much older. The most characteristic thing about the Moon to the naked eye are the craters, which are something like scars that witness the passage of time: the more softened, diffuse and even buried it appears on the map, the older it is. On the contrary, the sharper, brighter and surrounded by bright rays, the younger. “Lightning bolts” are bursts of dust and rock launched after impact and can extend for many kilometers. There is two especially spectacular craters on the map: Tycho and Copernicuswhose rays cross hundreds of kilometers and are geologically very recent. The part of the Moon that we never see from Earth and that arouses so much curiosity in us (there is a project to install a radio telescope there) is its hidden side: there are almost no blue spots there. And while the visible side is rich in lava plains, the hidden side is a highland fortress, much more rugged and with a significantly thicker crust. Map At its south pole is the basin South Pole-Aitkenthe largest known impact scar in the entire Solar System, with 2,500 km in diameter and 8 km deep. Precisely that area where there are shadow craters science hopes to find water frost. This geological imbalance between both sides suggests that the Moon is asymmetric inside, a mystery that is also on the table of the scientific community. In Xataka | The Earth’s seabed has always been a mystery: an amazing 3D map reveals it in unprecedented detail In Xataka | Astronomers have stitched together 10,000 images from the Webb telescope to make the largest map of the universe. Something doesn’t fit Cover | USGS, NASA

The Earth turned on its great geological engine billions of years earlier than we estimate. We know it from a microscopic crystal

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For a long time, textbooks They have painted the primitive Earth like a ball of infernal and static magma, being a “lid” of inert rock where life or complex geological movement was impossible. Specifically, it was thought that the plate tectonicsthe engine that shapes the continents and recycles our planet’s nutrients, had taken much longer to start. However, we were wrong. How he did it. Science, in a recent article, has just put on the table the definitive evidence that indicates that the Earth began to move much earlier than we believed: at least 3.3 billion years ago, and most likely, more than 4 billion ago. And the key is not in the gigantic mountains under our feet, but in small fragments of glass smaller than a grain of sand. And if we want to travel in geological time, you have to go to jack hillsin Western Australia, where the oldest known fragments of terrestrial rock are found. The protagonists of this story are zircon crystals, extremely resistant minerals that act as authentic geological hard drives. The interesting thing is that, when they form, they trap isotopes and tiny amounts of other elements inside that tell us exactly what the environment was like at the time of their crystallization. The results. According to detailed analysis that collects Natureand supported by key works such as those published in the prestigious magazine PNASthese S-type zircons hide unmistakable geochemical signatures. Specifically, they reveal that, instead of a static and dead Earth’s crust, subduction processes already existed. That is, the oceanic crust was already colliding and sinking under other plates, melting back into the Earth’s mantle. A double life. But researchers have not limited themselves to looking at a specific era, but have traced the proportions of trace elements such as uranium, niobium or scandium in different zircons from Australia, Greenland and South Africa. Here they observed that during the Eoarchean, the Earth did not have a single geological behavior. Instead, it had two tectonic regimes. The first of these, known as a ‘stagnant lid’ with areas of crust dominated by plumes of oceanic magma that simply pushed upwards. On the other hand, it also had the ‘moving lid’ zone, which were active zones where volcanic arcs were already forming and there was subduction, very similar to modern plate tectonics, recycling the Earth’s crust. But there is more. As if that were not enough, other published studies in Science and Geology have contributed even more pieces to the puzzle, such as the transform faults in the Pilbara Craton of Australia that show horizontal movements 3,000 million years ago, and even inclusions of fresh water in zircons from more than 4,000 million years ago, which suggests that there were already emerging continents interacting with the atmosphere and the water cycle. It changes everything. Knowing that plate tectonics started so early is not a mere geological whim, since tectonics is the Earth’s thermostat: it regulates the carbon cycle, releases fundamental gases into the atmosphere and creates the necessary environments for the chemical breeding ground. In this way, if more than 4,000 million years ago our planet was already recycling its crust, having primitive continents and fresh water, it means that the conditions for life to emerge occurred much earlier than what science books dictated. Once again, the Earth shows us that, from its most remote beginnings, it has always been a living world. Images | Javier Miranda In Xataka | There are scientists deliberately causing earthquakes in the Alps and they have a good reason for it

Spain turns in the opposite direction to the rest of Europe. Form part of a geological plan: closing the Mediterranean

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Spain and Portugal are dancing to a different rhythm than the rest of Europe. They are moving clockwise and the consequence is clear: a long-term closure of the Mediterranean that connects the Iberian Peninsula directly to North Africa. The convergence between continents is slow, a few millimeters a year (so we will continue needing the tunnel between Spain and Morocco), but one thing is clear: another Pangea is on the way. And the Iberian Peninsula and Morocco will be a unit. In short. Continental plates move. Some separate, others collide, and that continental drift has caused the emergence the Pangea Ultima theory. In 250 million years, there will only be one continent. There is a long way to go for that, but now, some researchers from the University of the Basque Country have analyzed geodetic data that allows them to affirm that the Iberian Peninsula is rotating clockwise. This east-west rotation is driven by the convergence between the Eurasian and African plates, and the conclusion is clear: both are moving between four and six millimeters closer each year. This information is not new, but the researchers’ discovery is to specify the processes that take place at the diffuse boundary of the two western Mediterranean plates. Thanks, Gibraltar. Although the boundaries of other plates are well defined, this does not occur in the Western Mediterranean. There, the processes are much grayer, and there is something called “Gibraltar Arch” which plays an interesting role in this tectonic dynamic. To the east of the strait, the crust absorbs the deformation caused by the collision between the Eurasian and African plates. This ‘Gibraltar Arc’ acts as a buffer, but it has a consequence: in the west of the strait there is a direct collision between the plates, while in the east it is absorbed by the Gibraltar Arc. This lack of buffering from the southwest is what causes the clockwise rotation. Rotational strain rate field. Positive values ​​correspond to clockwise rotation, while negative values ​​refer to counterclockwise rotation. Active and potentially active faults are marked with solid and dashed gray lines, respectively. Double analysis. The researchers combined two types of accuracy analyzes to obtain these results. On the one hand, those of satellite deformation through GNSS system (Global Navigation Satellite System). Analyzing the data, they measured surface displacements with millimeter precision, relying on both permanent and occasional GPS markers. On the other hand, they also analyzed information from recent earthquakes that allowed them to determine the tectonic “stresses” in the area. They are independent data sets, but by crossing them they were able to draw a series of ‘lines’ that have allowed them to better specify the boundary between the plates. So that? Well, to better understand which sectors are in direct collision between plates and which are still more protected by the Gibraltar Arc. And the neighbors? The problem is that, although they claim that it is a rapid tectonic movement, this is true in geological terms. For us it is invaluable, but it also comes into play that we only have satellite data since 1999 and detailed seismic data since the 1980s. Even so, if with such a short range of data we have reached that conclusion in the annual approach, it is because the phenomenon is not in a hurry, but it does not pause either. And the most interesting thing is that this only affects the Iberian Peninsula. It is not that we are going to separate from France, since we ‘drag’ the rest of the continent thanks to the effect of the Gibraltar Arc, but we are not turning in the same direction as other neighbors. Italy, for example, experiences a counterclockwise rotation that exerts pressure in the alpine zoneand in the anatolian plate (where most of Türkiye is), there is also this counterclockwise rotation. Hello, Morocco. While in Turkey the consequence may be more earthquakes or mountain formations, this current speed of between 4 and 6 millimeters will cause, at some point, the Iberian Peninsula and Morocco to unite. This continental collision would close the Mediterraneanbut there is a lot left for it. How much? About 100 million years. They estimate that for 20 million years we will continue at the same speed, but within about 50 million years, things will gain momentum, accelerating the process and turning the region into one of the most active volcanic and seismic areas on the planet. It’s… foolish to worry. present utility. Now, beyond curiosity, the most immediate implication that the researchers point out is a better identification of active faults or areas in which previously unidentified tectonic structures could exist. Asier Madarieta-Txurruka, one of those responsible for the investigation, explains This information indicates where to look for these structures and boundaries to determine what type of folds and faults there may be. Thus, we can anticipate the type of earthquake that there will be and its magnitude in areas such as the Western Pyrenees or the region of Cádiz and Seville in which we know that there are numerous places with significant deformationbut we do not have well identified the active tectonic structures that cause them. And, although there is still a long way to go before the Alps and a new mountain range are founded across the peninsula and all of North Africa to Arabia, knowing better what we have right under our feet is much more useful. In Xataka | We knew that Africa was going to split in half. What we didn’t know was that it would happen so quickly.

the science behind a geological risk that repeats itself every 1,200 years

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Although the tsunamis seem like effects that are reserved for the Japanese coasts, the reality is that Spain He also has many ballots to suffer an event of this magnitude on our coasts. Cádiz is one of the locations with the highest risk of suffering a tsunami in Spain, and the authorities wanted to verify that the emergency and response systems they work in case this type of event occurs at any time. In order to verify this, the authorities carried out a drill in mid-November in which the ES-Alert systemseveral schools and all emergency services. And given this great display, the question is mandatory: what are the chances of a tsunami occurring in Cádiz? Cádiz is at the center of this simulation because it is the area with the greatest danger from tsunamis in the country, due to the history behind it and the seismicity of the Azores-Gibraltar area. For this reason, the Junta de Andalucía has prepared a Emergency Plan for the Risk of Tsunami (PEMA) and has chosen Cádiz for the largest tsunami simulation carried out in Spain. Because. In the past, geological records indicate that at least five large tsunamis have occurred in the Gulf of Cádiz in the last 7,000 years. All of these associated with megaearthquakes at the plate boundary between Africa and Eurasia. Added to this is the historical reference: the tsunami linked to the Lisbon earthquake of November 1, 1755which completely flooded Cádiz and part of the Andalusian coast with waves of several meters in a matter of dozens of minutes. The paleoseismology works of the CSIC and several universities place the recurrence interval of these events between 1,200 and 1,500 yearslong enough to be socially forgotten, but too short to be ignored in risk planning. This places the southwest of the peninsula as one of the most exposed areas in Europe to tsunamis, despite the fact that the “perceived risk” on the street has historically been very low. And this is precisely something that has been analyzed in the layers of sand and marine remains left inland and that gives us information about what happened thousands of years ago. Although logically always with a time frame that is approximate. Why now. The fact of doing the simulation in this month of November may make us think that scientists have found evidence that a large tsunami is coming to Cádiz, but nothing could be further from the truth. What is happening in this case is that a risk that has been known for a long time and for which, until now, hardly anything had been tested on a large scale, is being taken more seriously. That is why this scientific evidence that tells us about the real risk that exists in this case on the coast of Cádiz has been transferred to the regulations. In 2015, the Basic Planning Guideline for Civil Protection against the Risk of Tsunamiwhich recognizes the Gulf of Cádiz as a critical area where the expected wave height exceeds 0.5 meters. A framework that is not limited to pretty maps, but defines decision guidelines according to magnitude and location of earthquakes, chains of command, warning protocols and response time objectives, with the National Geographic Institute, AEMET and the future SINAM network as input sensors. What has been simulated. In this case, Cádiz has simulated an earthquake with an approximate magnitude of 7.5-7.6 to the southwest of Cape San Vicente, very similar to the one in Lisbon in 1755 and which generates a tsunami that points directly to the western Andalusian coast. In this scenario, the propagation models estimate between 45 and 60 minutes from the activation of the alert until the arrival of the first wave from Cádiz, which in practice is the clock with which Civil Protection works. The objective of the exercise was to virtually save as many people as possible in that one-hour window: horizontal evacuation to non-flood areas, vertical evacuation to high floors, beach and port rescues, protection of cultural assets and management of damaged buildings were tested. On paper, all this already existed in manuals and maps; What was missing was to see how a real city behaves when a tsunami warning sounds in the middle of a work morning.​ Images | Matt Paul Catalano In Xataka | There are scientists deliberately causing earthquakes in the Alps and they have a good reason for it

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