**Evidence of the Zanclean megaflood in the eastern Mediterranean Basin**

“_Our findings provide evidence for a large amplitude drawdown in the Ionian Basin during the MSC, support the scenario of a Mediterranean-wide catastrophic flood at the end of the MSC, and suggest that the identified sedimentary body is the largest known megaflood deposit on Earth._”

Micallef, A., Camerlenghi, A., Garcia-Castellanos, D. et al. Evidence of the Zanclean megaflood in the eastern Mediterranean Basin. Sci Rep 8, 1078 (2018). https://doi.org/10.1038/s41598-018-19446-3.

#OpenAccess #OA #Article #DOI #Geology #Geomorphology #Geophysics #Sedimentology #Flood #Mediterranean #Academia #Academics @geology

Arctic Melt

Temperatures in the Arctic are rising faster than elsewhere, triggering more and more melting. Photographer Scott Portelli captured a melting ice shelf protruding into the ocean in this aerial image. Across the top of the frozen landscape, streams and rivers cut through the ice, leading to waterfalls that flood the nearby ocean with freshwater. This meltwater will do more than raise ocean levels; it changes temperature and salinity in these regions, disrupting the convection that keeps our planet healthy. (Image credit: S. Portelli/OPOTY; via Colossal)

9-month Geo position at Skidmore: earth materials, geophysical methods, intro. "Expertise in any of the following areas is desirable: #petrology, #mineralogy, #geophysics, tectonics, Earth history, and related fields." #geology

https://eodq.fa.us6.oraclecloud.com/hcmUI/CandidateExperience/en/sites/CX/job/2579

Reclaiming the Land

Lava floods human-made infrastructure on Iceland’s Reykjanes peninsula in this aerial image from photographer Ael Kermarec. Protecting roads and buildings from lava flows is a formidable challenge, but it’s one that researchers are tackling. But the larger and faster the lava flow, the harder infrastructure is to protect. Sometimes our best efforts are simply overwhelmed by nature’s power. (Image credit: A. Kermarec/WNPA; via Colossal)

Thawing Permafrost Primes Slumps

As permafrost thaws on Arctic hillsides and shorelines, the land often deforms in a unique fashion, known as a slump. Formally known as mega retrogressive thaw slumps, these areas superficially resemble a landslide. They’re also prone to repeat performances: as many as 90% of Canada’s Arctic slumps recur in the same place as previous slumps. Researchers used ground-penetrating radar and other tools to study the underground structure at slumps and found that several factors contribute to this repetitive cycle.

Seawater soaking into the foot of a hilly shore can destabilize the permafrost, creating a slump. That changes the nearby ground cover, exposing more permafrost to warming; their measurements showed this warming could extend tens of meters underground, priming the area for future slumps. Similarly, the mudslides and narrow ravines that form on an active slump also shift away ground cover and warm the underlying permafrost. Together, these factors suggest that once a slump forms, more slumps will occur as the underlying permafrost warms. (Image credit: M. Krautblatter; research credit: M. Krautblatter et al.; via Eos)

Geophones

https://lemmy.ca/post/41583006

Kinematic Evolution Of A Large Paraglacial Landslide In The Barry Arm Fjord Of Alaska
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https://doi.org/10.1029/2023JF007119 <-- shared paper
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https://doi.org/10.5066/P9EUCGJQ <-- shared technical article
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https://www.sciencebase.gov/catalogMaps/mapping/ows/5fff561ed34e592d8671ee85?service=wms&request=getcapabilities&version=1.3.0 <-- shared web mapping service
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#GIS #spatial #mapping #massmovement #landslide #engineeringgeology #remotesensing #sitespecific #LiDAR #iFSAR #paraglacial #kinematics #mapping #monitoring #spatialanalysis #spatiotemporal #fedscience #risk #hazard #glacier #retreat #climatechange #Alaska #BarryArm #fjord #hazardassessment #tsunami #wave #BarryGlacier #change #sensors #fieldwork #surveillance #melting #permafrost #Whittier #geophysics #geology #Alaska #geomorphometry #deglaciating
@USGS

European Geological Open Data (Map And Data) From The European Geological Data Infrastructure (EGDI)
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https://www.europe-geology.eu/data-tools/map-viewer/ <-- shared link to map viewer
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#geology #geosciences #earthsciences #data #spatialdata #criticalminerals #mining #geothermal #netzero #groundwater #carboncapture #ccs #GIS #spatial #mapping #opendata #webmapping #mapportal #Europe #EGDI #framework #GSEU #resources #naturalresources #opendata #water #naturalresources #geomorphology #bathymetry #geophysics #topobathy #remotesensing #earthobservation #waterresources

“Visions in Ice”

The glittering blue interior of an ice cave sparkles in this award-winning image by photographer Yasmin Namini. The cave is underneath Iceland’s Vatnajokull Glacier. Notice the deep scallops carved into the lower wall. This shape is common in melting and dissolution processes. It is unavoidable for flat surfaces exposed to a melting/dissolving flow. (Image credit: Y. Namini/WNPA; via Colossal)

For more insight into the tectonic background of today’s M7.7 #earthquake in Myanmar I’d recommend this blog post and the original article on extrusion tectonics. There is also a video hiding somewhere on YouTube that illustrates this experiment perfectly.
#myanmar #geology #geoscience #tectonics #geophysics
https://blogs.egu.eu/divisions/ts/2021/02/15/ts-must-read-tapponnier-et-al-1982-propagating-extrusion-tectonics-in-asia/

Through-hole circuit bliss: the Geonics EM61mk2

https://lemmy.ca/post/41295802

Slipping Ice Streams

The Northeast Greenland Ice Stream provides about 12% of the island’s annual ice discharge, and so far, models cannot accurately capture just how quickly the ice moves. Researchers deployed a fiber-optic cable into a borehole and set explosive charges on the ice to capture images of its interior through seismology. But in the process, they measured seismic events that didn’t correspond to the team’s charges.

Instead, the researchers identified the signals as small, cascading icequakes that were undetectable from the surface. The quakes were signs of ice locally sticking and slipping — a failure mode that current models don’t capture. Moreover, the team was able to isolate each event to distinct layers of the ice, all of which corresponded to ice strata affected by volcanic ash (note the dark streak in the ice core image above). Whenever a volcanic eruption spread ash on the ice, it created a weaker layer. Even after hundreds more meters of ice have formed atop these weaker layers, the ice still breaks first in those layers, which may account for the ice stream’s higher-than-predicted flow. (Image credit: L. Warzecha/LWimages; research credit: A. Fichtner et al.; via Eos)

Salt Affects Particle Spreading

Microplastics are proliferating in our oceans (and everywhere else). This video takes a look at how salt and salinity gradients could affect the way plastics move. The researchers begin with a liquid bath sandwiched between a bed of magnets and electrodes. Using Lorentz forcing, they create an essentially 2D flow field that is ordered or chaotic, depending on the magnets’ configuration. Although it’s driven very differently, the flow field resembles the way the upper layer of the ocean moves and mixes.

The researchers then introduce colloids (particles that act as an analog for microplastics) and a bit of salt. Depending on the salinity gradient in the bath, the colloids can be attracted to one another or repelled. As the team shows, the resulting spread of colloids depends strongly on these salinity conditions, suggesting that microplastics, too, could see stronger dispersion or trapping depending on salinity changes. (Video and image credit: M. Alipour et al.)

Don't @ me

https://lemmy.ca/post/40417023

Daily report

Here are today's most popular trending hashtags on our website ️:

#cosmos, #science, #wonder, #space, #linuxgaming, #gaming, #geophysics, #ubuntu, #steam, #astrophotography, #unix

Stay tuned!

Flooding the Mediterranean

Nearly 6 million years ago, the Mediterranean was cut off from the ocean and evaporated faster than rivers could replenish it. This created a salty desert that persisted until about 5.3 million years ago. One hypothesis — the Zanclean megaflood — suggests that the Mediterranean refilled rapidly through an erosion channel near the Strait of Gilbraltar. A new study bolsters the concept by identifying geological features near Sicily consistent with the megaflood.

The team point to a grouping of over 300 ridges near the Sicily Sill, once a land bridge dividing the eastern and western Mediterranean and now underwater. The ridges are layered in debris but aren’t streamlined, suggesting they were rapidly deposited by turbulent waters, and date to the period of the proposed flooding. For more on the Zanclean Flood, check out this older post. (Image credit: R. Klavins; research credit: A. Micallif et al.; via Gizmodo)

[First results from #DORN on the #Moon] The recovery of samples of #regolith and lunar rocks, coupled with the analysis of #surface gases by the #DORN instrument, has enabled the scientists involved in the #ChangE6 mission to identify the occurrence of two volcanic episodes on the far side of the Moon, 4.2 and 2.8 billion years ago. For the record, the samples brought back by the #Apollo and #Luna missions from the visible side of our satellite attest to a single volcanic event, dating back more than 3 billion years.

Further analyses are underway, which will “refine previous observations made by remote sensing, which have shown that the far side of the Moon is different, in terms of #geophysics (differences in crustal thickness, for example) and the chemical and mineralogical composition of the rocks, from that of the visible side”, explains Pierre-Yves Meslin, astronomer at IRAP.

Info+ : https://www.polytechnique-insights.com/tribunes/espace/la-face-cachee-de-la-lune-les-premiers-echantillons-arrivent-sur-terre/

Grfin Tools—User Guide And Methods For Modeling Landslide Runout And Debris-Flow Growth And Inundation
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https://pubs.usgs.gov/publication/tm14A3 <-- shared USGS publication
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https://code.usgs.gov/grfintools/grfintools <-- shared USGS software release
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H/T Jonathan Perkins USGS
[ another open source resource for everyone from the USGS ~smile~ ]
#GIS #spatial #mapping #opensource #openlibrary #Grfin #software #package #regional #debrisflow #engineeringgeology #geology #inundation #spatialanalysis #spatiotemporal #geophysics #geophysical #massmovement #landslide #lahar #volcano #rock #avalanche #model #modeling #statistical #geostatistics #water #hydrology #downstream #elevation #remotesensing #DEM #flow #runout #risk #hazard #tools #slope #erosion #drainage #network #channel #channelisation #userguide
@USGS

Perhaps now more important than ever: The AGU Bridge Program! Deadline is March 18, but there are helpful office hours for student applicants today Feb 21 & Mar 12.

https://www.agu.org/learn-and-develop/learn/travel-research-grants/agu-bridge-program

Danish seismologist and geophysicist Inge Lehmann died #OTD in 1993.

She is best known for her discovery in 1936 of the solid inner core that exists within the molten outer core of the Earth. The seismic discontinuity in the speed of seismic waves at depths between 190 and 250 km is named the Lehmann discontinuity after her. Lehmann is considered to be a pioneer among women and scientists in seismology research.

https://en.wikipedia.org/wiki/Inge_Lehmann