Mastodawn

Pretty ugly on the landscape, but stunning when seen by shaded lidar. The projections at the periphery are slate waste tips.

Alexandra slate quarry, Moel Tryfan, north Wales.

#lidar #heritage #quarries

JanPV Apr 10

If you like your adits and industrial archaeology, here's a free, very visual write-up for you about the mile-long Penrhyn quarry drainage adit, built 1847-1849, possibly involving some Latter Day Saint drivers, though we failed to find definitive evidence so far.

https://drive.google.com/file/d/123Y8_sbTebF_sm_AcUcs4BqjjQcNxyeC/view?usp=sharing

#heritage #quarries #mines #slate #wales #cymru #industrialarchaeology #ia

Penrhyn_Drainage_Adit.pdf

Google Docs

JanPV Apr 6

Nice to go underground for a couple of hours to see my old 1862 friend, No. 2 hydraulic pump at a north Wales slate quarry. This kept levels 120 feet below this floor free of flooding and operated for a century with little maintenance. Its fuel was the original, free renewable: a head of water.

#ia #cymru #wales #engineering #mines #quarries #heritage

JanPV Mar 31

This afternoon's completion of documenting work I started back in 2022. This is 500m inside a mountain of alternating slate beds and grits. The dip of the slate beds is remarkably clear here. Time travel, back to 1847 when this drainage adit was started, and simultaneously 500 million years back to when this was all deep sea sediment.

#geology #rocks #cymru #wales #mines #quarries

JanPV Mar 31

The fascinating geological world of the 1.7km-long Penrhyn quarry drainage adit, driven 1847-49.

#geology #quarries #cymru #wales

Show thread

knizer Oct 30, 2025

#BostonWeekend 18x Sat SOMERVILLE ROCKS 11am 90 min walking tour of the Secret Quarries of #SomervilleMA - starts at Somerville Museum. $15+ https://www.somervillemuseum.org/calendar-events/ghosts-of-somerville-3-5btw9-4n7lx #Boston #SomervilleMuseum #geology #rocks #quarries #quarry #WalkingTour

Secret Quarries of Somerville — Somerville Museum

Visit the city’s oldest burial ground, where friendly ghosts will tell you about their lives in 18th century Somerville. Learn about our city’s past from those who lived it. Part of Somerstreets: Monster Mash Free and Open to th

Somerville Museum