Talcott Basalt Pillows

Talcott Basalt Pillows, Meriden, Connecticut, August, 2023. Photograph by Ophelia W. Ravenia.

If you need pillows, Target seems a sensible enough place to find some. If you want to check out some truly special pillows, then the Target store in Meriden, Connecticut is the place to go. Not because of the shop, but because of what’s behind it. Behind Target is an entire wall of pillows– specifically, basalt pillows. Geologically, this region is notable for its traprock hills and their dramatic escarpments. This creates a varied landscape with gorgeous stone ledges.

Talcott Basalt Cliff Face. Meriden, Connecticut, August, 2023. Photograph by Ophelia W. Ravenia.

During the Mesozoic period, this region was volcanically active and covered by a deep lake. This created the perfect conditions for basalt pillows to form. Basalt pillows are a type of rock formation that occurs when magma meets a cool liquid– such as water or mud. As magma is expelled into the cool liquid, the exterior of the magma rapidly forms a crust. This creates rounded, bubble-like structures that cool into igneous rock. As magma continues to be expressed, additional pillows form.

This specific formation is known as the Talcott lava flow, and it is one of the oldest and largest lava flows in the southern Connecticut River valley. The cliff face behind Meriden’s Target is one of the best, if not the best, places to see basalt pillows in New England.

Along with being visually interesting in terms of its form, the basalt pillows have multiple mineral inclusions, including small crystals– notably quartz, amethyst, and calcite.

Examples of rocks and crystals from the Talcott Basalt Formation. Meriden, Connecticut, August, 2023. Photograph by Ophelia W. Ravenia.

Talcott Basalt Pillows Meriden, Connecticut, August, 2023. Photograph by Ophelia W. Ravenia.

Talcott Basalt Cliff Face. Meriden, Connecticut, August, 2023. Photograph by Ophelia W. Ravenia.

To visit the Talcott basalt pillows, head to 474 Chamberlain Highway, Meriden, Connecticut. The basalt pillows are on a cliff face directly behind Target. They can be observed from the parking lot and loading dock area. The base of the cliff face is partially conservation land, and you should check in with the store’s facilities manager before getting up close to the basalt pillows. Getting up close to the cliff face involves rocky, uneven terrain, so it may not be accessible for folks with mobility challenges.

 

Sources & Further Reading:

Further information on the geology of Meriden and the surrounding area is available here:

guidebookno4guidetothemesozoicredbedsofconnecticut1978pdf.pdf

https://www.meridenct.gov/file-repository/DownloadFile.aspx?FileID=159


Information on the geology of the Talcott basalt flow is available here:

https://www.mindat.org/loc-123540.html

https://scholars.unh.edu/cgi/viewcontent.cgi?article=1316&context=neigc_trips


Additional information on the formation of basalt pillows can be found here:

https://www.nps.gov/articles/000/pillow-basalts.htm


A short video of basalt pillow formation is available here:

https://uportland.mediaspace.kaltura.com/media/CEE1+-+Pillow+Basalt+Formation+%28topic+7+supplemental%29/0_vug4gj06



Vocabulary:

Escarpment- A long, steep slope, typically at the edge of a plateau or otherwise separating land of significantly different height.

Igneous- Rocks composed of cooled and hardened lava or magma.

Mesozoic Period- a geologic period spanning from circa 252 to circa 66 million years ago

Trap Rock- Basalt or any other dark, fine grained igneous rock.