The part and counterpart of a clam geode. The mouth of the clam is pointed down and there is a wedge of cemented sandstone at the bottom; the upper 2/3 of the clam is infilled with incredible amber colored dogtooth spar calcite, about 6-8 mm thick.

The part and counterpart of a clam geode. The mouth of the clam is pointed down and there is a wedge of cemented sandstone at the bottom; the upper 2/3 of the clam is infilled with incredible amber colored dogtooth spar calcite, about 6-8 mm thick.

The part and counterpart of a clam geode. The mouth of the clam is pointed down and there is a wedge of cemented sandstone at the bottom; the upper 2/3 of the clam is infilled with incredible amber colored dogtooth spar calcite, about 6-8 mm thick.

#fossilfriday After 20 years, I finally found clam geodes in the Purisima Formation in Santa Cruz, CA! These are ~5 myo Clinocardium (cockle) shells that were incompletely filled in by sediment after death. Groundwater rich in dissolved calcium carbonate then precipitated calcite crystals.

Photograph of a pale brown rock surface with a human hand for scale, showing a roughly circular textured pattern in the sandstone surface which is thought to be the feeding trace of a polychaete worm.

Amazing trace fossil - Zoophycos - from the mid-Miocene sediments of the Tabernas basin, Almeria. First time to have seen this, in many years of field visits - spotted by eagle-eyed 3rd year @oxuniearthsci.bsky.social students. ⚒️

Rocks and sand. NASA/JPL-Caltech/ASU/Kevin M. Gill

More of this really interesting rock that’s been the focus of study for the Mars Perseverance Rover for a few sols. This was taken on Sol 1803 using MastCam-Z.

flic.kr/p/2s2LGDc

A coarse-grained, almost phaneritic, rock on Mars. And sand. NASA/JPL-Caltech/ASU/MSSS/Kevin M. Gill

I'm loving the texture of rocks that are being studied by the Perseverance Rover lately. Can't wait for the expert opinion! This image was taken a few hours ago tosol (Sol 1801) using MastCam-Z.

flic.kr/p/2s2fuPu

How Geoscientists Think and Learn - Eos Geoscientists have a select set of skills that help them make sense of the complicated and chaotic Earth system.

Two key features of geoscientists’ temporal thinking stand out: "They take a long view of time, and they expect low-frequency, high-impact events. Geoscientists have internalized the vastness of the age of the Earth and the relative brevity of human history."

eos.org/features/how...

New paper out on the results of the TMARS project led by Myriam Lemelin and students: mapping, mineralogy and geochemistry of reactive gossans in permafrost, a #Mars analogue in the Canadian #Arctic. @richleveille.bsky.social @usherbrooke.bsky.social

www.sciencedirect.com/science/arti...

A large specimen of pink rubellite columnar crystals in radiating clusters along central points or lines, in fine grained lepidolite. It sits on the bottom shelf in a display case with a small label to the lower right. At the Natural History Museum in London.

Pink rubellite, usually a variety of elbaite (a tourmaline), in pale purple lepidolite (a mica) looking like a bunch of sea creatures. #MineralMonday #GeoscienceBluesky ⚒️🧪

T.S. Thursday:
2.8 Ga Granodiorite from the Beartooth Mtns, MT in crossed polars and cathodoluminescence. In CL the red zone between microcline and plagioclase is a fine-grained myrmekite (plagioclase and quartz intergrowths). Contributed by Darrell Henry.
#thinsectionthursday

Close-up of a textured surface showing concentric circular patterns with fine ridges and grooves in grayscale.

HiRISE 4K: Weird Crater Features

In a Context Camera image of this area, the crater floor has hollows and a high density of pits.

Full cutout on Flickr: https://flic.kr/p/2rYiTR6
NASA/JPL-Caltech/University of Arizona
#Mars #NASA #science

3D image shows a part of an eroded impact crater with incised gullies on the wall and folded terrain at the bottom of the slope. The scene is less than 5 km, or 3 miles, across.

HiRISE 3D: A Crater in Utopia Planitia

This 3D image shows us the eastern part of an old impact crater with incised gullies and a deformed floor. The entire crater is about 10 km across.

www.uahirise.org/anaglyph/ESP_037646_2290...
NASA/JPL-Caltech/University of Arizona

HiPOD: Knobs in East Candor Chasma

This features an interesting area of possible deformation of lacustrine sediment. This observation was requested to support geologic mapping. Candor Chasma is one of the largest canyons that make up Valles Marineris.

https://uahirise.org/hipod/ESP_076713_1730

A cut fact of a basaltic pillow with the quenched pillow rind on the left (swiss army knife for scale).

A transmitted light photo of a thin section spanning the pillow rind on the left to the pillow interior. Gas bubbles show as round white patches within the pillow interior. Horizontal field of view 3.5 cm

Hand sample and thin section of a pillow rind and interior from Palaeogene lavas of eastern Baffin island. The solidifying melt continued to exsolve gas bubbles, trapped in the pillow interior by the rind.

#ThinsectionThursday #BaffinIsland #Basalt #Geology

And through the looking glass; here is a lake on an island in a lake on an island. Lake Taal caldera and volcanic island (with crater lake) on Luzon, Philippines.🌋⚒️🧪

Image cutout shows a long and curvy ridge that is separated in section on the floor of a large canyon on the surface of Mars.

HiPOD: A Sinuous Ridge in Mareotis Fossae

The sinuous ridge is approximately 10 meters wide and several kilometers long. The floor surrounding this ridge has been eroding laterally, forming pits and circular features.

More: https://uahirise.org/hipod/ESP_088990_2150
#Mars #NASA #science

Arviat, Nunavut, chosen as main campus site for Canada's 1st Inuit university | CBC News Arviat, a small Nunavut community located along the western shore of Hudson Bay, will be the home of the first Inuit-led university in Canada's Arctic, CBC News has learned.

www.cbc.ca/news/politic...

Image cutout shows a pedestal crater on the surface of Mars. The ejecta blanket from the original impact is still visible around the crater, because it was more resistant to erosion than the surrounding terrain.

A closeup of the impact crater. The crater rim is very eroded and there are numerous large boulders around the crater.

HiPOD: About a Pedestal Crater

The objective of this observation is to examine a pedestal crater here in Deuteronilus Mensae. A pedestal crater is when the ejecta from an impact settles and is more erosion-resistant than the surrounding terrain.

https://uahirise.org/hipod/ESP_076643_2260
#Mars

HiPOD: Possible Chloride-Rich Terrain

Most suspected chloride deposits in the Eridania Basin are high-albedo and found in flattish areas. Around the eastern rim of the basin, some of these chlorides are distinctively low-albedo, and found in channels.

https://uahirise.org/hipod/ESP_076638_1505

HiPOD: Ridges in Arabia

The objective of this observation is to determine the nature of narrow ridges. They may be from faults produced during old impacts. If so, recent research suggests they may be related to clay deposits.

https://uahirise.org/hipod/ESP_076616_2085
#Mars #NASA #science

Schematic summary of the eruptive history of Kolumbo Volcano.

🚨Check out our new IODP paper on Kolumbo Volcano in Greece. Despite being one of Europe's most dangerous volcanoes not much is known about its eruptive history. The paper led by @abigaillily.bsky.social adds important insight into the Kolumbo-Santorini system
pubs.geoscienceworld.org/gsa/geology/...

Fractured glassy breccia meets bubbly microcrystalline basalt in a hyaloclastite from Iceland (or is it Greenland, I can never remember...).

#thinsectionthursday #geology #science #minerals #rocks #microscope #microscopy

Thin Section Thursday!
Julian schist: Mica schist in XPL from the Julian Schist at Julian, California USA. Contributed by Paolo Sanchez.
You can contribute too! Send image(s) and short caption to akoziol1 (at) udayton dot edu. #thinsectionthursday

3D image shows a long, light-toned inverted channel extending from the upper left of the picture down past the center. There is an impact crater that likely formed after the channel that still connects both sections. The scene is less than 5 km, or 3 miles, across.

HiRISE 3D: An Inverted Channel in Flammarion Crater

This image shows a spectacular inverted channel and marginal deposits in Flammarion Crater in Arabia Terra. Is it an exhumed channel belt deposit?

www.uahirise.org/anaglyph/ESP_090330_2065...

#Mars #NASA #science

Can you guess what the editorial on the latest volume of @wearetektonika.bsky.social is about from the cover I designed for it? 🤖✨

(Yes, It's about AI in science - what is acceptable...and what maybe isn't)

Read it for free at tektonika.online/index.php/ho...

#SciArt #EarthScience #DOAJ

1/2 *Call for Abstracts*! GAC-MAC 2026 will be held in St. John’s, NL. Consider submitting an abstract to SS22: Exploring the Magmatic Framework of Continental Large Igneous Provinces and their Ni-Cu-PGE Prospectivity.

2/2 This Special Session celebrates the contributions of W.R.A. (Bob) Baragar in the fields of igneous petrology and geochemistry. Co-convened with @bodriscollearth.bsky.social and @thejow.bsky.social on behalf of the #MackenzieLIP project team.

Pyrope and minor kyanite in matrix of phengite and palisade-textured quartz from Dora Maira. Section is slightly above standard thickness.

Pyrope and minor kyanite in matrix of phengite and palisade-textured quartz from the Dora Maira massif, N. Italy. Section is slightly above standard thickness.
#thinsectionthursday

#thinsectionthursday

An image of a rock thin section viewed under the microscope in cross polarised light. The sample is dominated by large olivine and clinopyroxene crystals which are exhibiting bright second order interference colours. They are set in a much finer groundmass which contains abundant plagioclase crystals, recognisable through their first order grey interference colours and long, thin crystal shapes. Large vesicles are scattered through the sample, appearing rounded and black.

Olivine and clinopyroxene phenocrysts in a plagioclase-rich groundmass - Vesicular basalt lava flow, Azores

#thinsectionthursday #geology #science #minerals #rocks #microscope #microscopy

HiPOD: Faulting Mars

This region of Xanthe Terra has mostly been contracted due to thrust faulting, but this local region shows evidence of extensional faulting, also called normal faulting.

https://uahirise.org/hipod/ESP_045497_1800
NASA/JPL-Caltech/University of Arizona
#Mars #science #NASA

Image cutout shows large exposures of bright-toned bedrock in several areas on the wall of a basin the Melas Chasma on Mars.

Enhanced color cutout shows a closeup of the exposed, light-toned bedrock. Some of the scene has dark terrain, and there are numerous boulders throughout the image.

HiPOD: Valleys and Inverted Channels

This observation features a series of interstratified valleys and inverted channels at the western end of the southwestern basin in Melas Chasma. Melas is part of the largest canyon system on Mars, Valles Marineris.

https://uahirise.org/hipod/ESP_076621_1710