Chris White · @Ceedave
151 followers · 275 posts · Server sciencemastodon.com
Interesting #boulders in a roughly stacked #seawall
The southern part of the spit separating #Plymouth Harbor from Plymouth Bay has a seawall along the outer shore, above Plymouth #LongBeach. Without knowing where they came from, interpreting the boulders is sketchy. BUT nice coarse crystals in intrusions into #felsic rocks, including big #quartz chunks (top right photo) and blades of #biotite (bottom right).
#Massachusetts #igneous #geology #intrusion #pegmatite #NewEngland #dike #rock #beach
#boulders #seawall #plymouth #longbeach #felsic #quartz #biotite #massachusetts #igneous #geology #intrusion #pegmatite #newengland #dike #rock #beach
Chris White · @Ceedave
151 followers · 275 posts · Server sciencemastodon.comInteresting #boulders in a roughly stacked #seawall
The southern part of the spit separating #Plymouth #Harbor from Plymouth Bay has a seawall along the outer shore, above Plymouth #LongBeach. Without knowing where they came from, interpretation is sketchy. But nice coarse crystals in intrusions into #felsic rocks, including big #quartz chunks (top left photo) and blades of #biotite (bottom left). #Massachusetts #igneous #geology #intrusion #pegmatite #granite #NewEngland #dike #rock #beach
#boulders #seawall #plymouth #harbor #longbeach #felsic #quartz #biotite #massachusetts #igneous #geology #intrusion #pegmatite #granite #newengland #dike #rock #beach
Chris White · @Ceedave
151 followers · 276 posts · Server sciencemastodon.comApple Maps image of area, my #photos #Fujifilm #xe2 #Massachusetts #NewEngland #beach #igneous #geology #granite #intrusive #rock
#photos #fujifilm #xe2 #massachusetts #newengland #beach #igneous #geology #granite #intrusive #rock
Chris White · @Ceedave
150 followers · 271 posts · Server sciencemastodon.com
Above and upon #igneous #dikes
The feature sure looked like a #dike on #satellite view, and a ground check confirmed it. Probably a late #Triassic or early #Jurassic intrusion into #Proterozoic Dedham #Granite, as #Pangea rifted. At Black Rock #Beach, #Hingham, #Massachusetts, #NewEngland #geology USA.
Satellite view from #AppleMaps, #photo by me.
#igneous #dikes #dike #satellite #triassic #jurassic #proterozoic #granite #pangea #beach #hingham #massachusetts #newengland #geology #applemaps #photo
BrownsBay · @brownsbay
135 followers · 256 posts · Server pnw.zone
Rock on the beach at Barnum Point, Camano Island, WA. Looks like a granodiorite peppered with xenoliths. Igneous petrologists chime in. Likely weathered out of the till that caps the bluffs or a dropstone from floating ice on marine water incursion during the Everson interstade. Source rock provenance not known. Ref. Geologic map of the Juniper Beach 7.5-minute quadrangle, WDGER Geologic Map GM70. #geology #igneous #xenolith #iceage #glaciation #intrusive #PNW #washingtonstate #CamanoIsland
#geology #igneous #xenolith #iceage #glaciation #intrusive #pnw #washingtonstate #camanoisland
Chris White · @Ceedave
108 followers · 134 posts · Server sciencemastodon.com
Sort of #selfPortrait in #QuincyGranite
The spectral form, like Jesus looming out of a piece of toast, is me, taking a #photo of a circa 1.5 meter polished granite sphere in the #MountWollastonCemetery in #Quincy. The largest visible #crystals (#feldspar and #amphibole) are about 1 centimeter across.
#Fujifilm #XH1 23mm f/1.4 @ f/2 and 1/1100 s
#igneous #stone #cemetery #Massachusetts #NewEngland #monument #sphere #reflectionselfie #reflection #geology #geoscience #quarry
#selfportrait #quincygranite #photo #mountwollastoncemetery #quincy #Crystals #feldspar #amphibole #fujifilm #xh1 #igneous #stone #cemetery #massachusetts #newengland #monument #sphere #reflectionselfie #reflection #geology #geoscience #quarry
Chris White · @Ceedave
108 followers · 134 posts · Server sciencemastodon.comSort of #selfPortrait in #QuincyGranite
The spectral form, like Jesus looming out of a piece of toast, is me, taking a #photo of a circa 1.5 meter polished granite sphere in the #MountWollastonCemetery in #Quincy. The largest visible #crystals (#feldspar and #amphibole) are about 1 centimeter across.
#Fujifilm #XH1 23mm f/1.4 @ f/2 and 1/1100 s
#igneous #stone #cemetery #Massachusetts #NewEngland #monument #sphere #reflectionselfie #reflection
#selfportrait #quincygranite #photo #mountwollastoncemetery #quincy #Crystals #feldspar #amphibole #fujifilm #xh1 #igneous #stone #cemetery #massachusetts #newengland #monument #sphere #reflectionselfie #reflection
Chris White · @Ceedave
106 followers · 128 posts · Server sciencemastodon.com
Now the more #riebeckite facies of the #Paleozoic #Quincy #Granite
The Quincy granite was a prized architectural stone, most famously used in the #BunkerHill Monument in #Boston #Massachusetts. Current dating suggests it was intruded into #Avalonia before it glommed onto #Laurentia as #Laurasia and #Pangea were assembled. Today’s #photo set comes from a walk around the eponymous Bunker Hill Quarry. I’ll post more about the history later. Captions!
#Fujifilm #XH1 #igneous #intrusive #NewEngland
#riebeckite #Paleozoic #quincy #granite #bunkerhill #boston #massachusetts #avalonia #laurentia #laurasia #pangea #photo #fujifilm #xh1 #igneous #intrusive #newengland
Chris White · @Ceedave
106 followers · 128 posts · Server sciencemastodon.comNow the more #riebeckite facies of the #Paleozoic #Quincy #Granite
The Quincy granite was a prized architectural stone, most famously used in the #Bunker#Hill Monument in #Boston #Massachusetts. Current dating suggests it was intruded into #Avalonia before it glommed onto #Laurentia as #Laurasia and #Pangea were assembled. Today’s #photo set comes from a walk around the eponymous Bunker Hill Quarry. I’ll post more about the history later. Captions!
#Fujifilm #XH1 #igneous #intrusive #NewEngland
#riebeckite #Paleozoic #quincy #granite #bunker #boston #massachusetts #avalonia #laurentia #laurasia #pangea #photo #fujifilm #xh1 #igneous #intrusive #newengland
Chris White · @Ceedave
103 followers · 119 posts · Server sciencemastodon.com
Quincy or #BlueHills #Porphyry #Granite
An alkaline, nonorogenic granite intruded into #Avalonia in the #Silurian / #Ordovician as it cruised from peri-#Gondwana to #Laurentia, before assembling #Pangea in the #Acadian #Orogeny (#Devonian). It’s coarse, with the #phenocrysts of amphiboles(?) (possibly riebeckite?)…I’m no petrologist. From@the Eaton’s Pond conservation area@at the #Braintree #Quincy border. My photos.
#geology #igneous #Massachusetts #Boston #NewEngland #Fujifilm #photo
#bluehills #porphyry #granite #avalonia #silurian #Ordovician #gondwana #laurentia #pangea #acadian #orogeny #devonian #phenocrysts #braintree #quincy #geology #igneous #massachusetts #boston #newengland #fujifilm #photo
Ralph Brooker · @RalphBrooker
110 followers · 1484 posts · Server mstdn.socialICYI Many areas of charred #Bordeaux forest floor (summer wildfires of 2022) are still not just smouldering but bursting into campfire size fires. If I understood the reporting correctly the substratum is #igneous rock. (#Francetele #infos)
#infos #francetele #igneous #bordeaux
Chris White · @Ceedave
97 followers · 110 posts · Server sciencemastodon.com
@vickyveritas I confess I’m not sure what ignimbrite really means, in terms of mineralogy or deposition. But I have a photo of a possible #lapilli tuff in the #Blackstone Group in #RhodeIsland (that I’ve posted before, it’s associated with mafic pillows but appears felsic).
#igneous #ignimbrite #fujifilm #XH1 27mm f/2.8 f/8 1/125 s ISO 800
#lapilli #blackstone #rhodeisland #igneous #ignimbrite #fujifilm #xh1
Tim Demko · @rock_jockey
852 followers · 2062 posts · Server sciencemastodon.com@seelix “Pebble” is a defined grain size classification on the Wentworth scale for sediments
https://www.jstor.org/stable/30063207#metadata_info_tab_contents
As a sedimentologist, I’m intrigued by the brand name, but I think “Fruity Phenocrysts” sounds fun, and “Fruity Porphyroblasts” sounds even funner.
#geology #sediments #geoscience #EarthScience #igneous #metamorphic @geoscience
#geology #sediments #geoscience #igneous #Metamorphic #earthscience
Chris White · @Ceedave
87 followers · 87 posts · Server sciencemastodon.com
We walked around #Cohasset, #Massachusetts #USA in the unusually warm (50 F, 10 C) “winter” weather here in #NewEngland. This is an (absurdly) prosperous #coastal community just south of #Boston. The walk included lovely views across coves and marshes (including #invasive Phragmites australis and #peat under #native #Spartina), as well as nice exposures of the > 600 Ma #Dedham #granite, the #pluton coring most of the #Avalon terrane in this area.
#photo #igneous #Proterozoic #geology #saltMarsh
#cohasset #massachusetts #usa #newengland #Coastal #boston #invasive #peat #native #spartina #dedham #granite #Pluton #avalon #photo #igneous #proterozoic #geology #saltmarsh
Jerry D. Harris 🦕👣 · @dinogami
226 followers · 543 posts · Server sauropods.win
Agathla Peak, a volcanic neck in the Navajo Volcanic Field (along with its more famous cousin, Shiprock), located north of Kayenta, Arizona and just south of Monument Valley. Agathla is composed of volcanic breccia cut by several dikes. It's about 25–30 million years old. #geology #geoscience #volcano #igneous #arizona #naturalhistory #navajo
#geology #geoscience #volcano #igneous #arizona #naturalhistory #navajo
GregCocks · @GregCocks
89 followers · 98 posts · Server techhub.social
The Eye Of The Sahara - A Geological Mystery Staring Into Space
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https://www.iflscience.com/the-eye-of-the-sahara-a-geological-mystery-staring-into-space-67179 <-- shared article
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https://doi.org/10.1016/j.jafrearsci.2014.04.006 <-- shared paper
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https://doi.org/10.1007/s12517-021-08734-4 <-- shared paper
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#GIS #spatial #mapping #remotesensing #satellite #Landsat #imagery #gischat #EyeOfTheSahara #vulcanism #intrusion #geology #Africa #RichatStructure #research #mauritania #structuralgeology #anticline #folding #sedimentary #igneous #formation #megabreccia #geologicalheritagesites
#gis #spatial #mapping #remotesensing #satellite #landsat #imagery #gischat #eyeofthesahara #vulcanism #intrusion #geology #africa #richatstructure #research #Mauritania #structuralgeology #anticline #folding #sedimentary #igneous #formation #megabreccia #geologicalheritagesites
Chris White · @Ceedave
63 followers · 63 posts · Server sciencemastodon.com
Proterozoic Mattapan Volcanics (Zm)
These felsic rocks are exposed on the south of the Boston Basin, and lay between the Dedham Granite and the Roxbury Conglomerate. They correlate to the Lynn Volcanics in Middlesex Fells and elsewhere north of Boston. The Roxbury (PzZr) mapped on Hough’s Neck (east of “Quincy”, map) is at least partly Mattapan, as seen at Rock Island (lower photos), which was quarried for “trap rock” ~ 1910. See captions for more.
#volcanics #igneous #geology #Boston #Quincy
#volcanics #igneous #geology #boston #quincy
Chris White · @Ceedave
63 followers · 63 posts · Server sciencemastodon.comProterozoic Mattapan Volcanics (Zm)
These felsic rocks are exposed on the south of the Boston Basin, and lay between the Dedham Granite and the Roxbury Conglomerate. They correlate to the Lynn Volcanics in Middlesex Fells and elsewhere north of Boston. The Roxbury (PzZr) mapped on Hough’s Neck (east of “Quincy”, map) is at least partly Mattapan, as seen at Rock Island (lower photos), which was quarried for “trap rock” ~ 1910. See captions for more.
#volcanics #igneous #geology #Boston #Quincy
#volcanics #igneous #geology #boston #quincy
Tim Holt-Wilson · @timholtwilson
233 followers · 91 posts · Server mastodon.green
Looking like some sort of lithified black pudding, a polished, porphyritic rhyolite or ignimbrite pebble from ploughsoil at Finningham (Suffolk, UK) is most likely an erratic from the Ordovician of North Wales, arrived via an early Pleistocene river.
#Suffolk #igneous #geology
Chris White · @Ceedave
60 followers · 50 posts · Server sciencemastodon.com
@BrianPierce Just looking at the orientation of Maiden Cliff in Camden Hills State Park, it appears to face too much to the west. The bedrock map shows (hard!) Devonian intrusive rock at that location (“D1”) on the map crop below, so I suspect that is resistance to erosion rather than glacial plucking…just guessing!
#geoscience #geology #bedrock #map #Maine #NewEngland #igneous
#geoscience #geology #bedrock #map #maine #newengland #igneous