Happening unseenLandscape
Kettle holes: ponds and hollows left by melting glacial ice
When: All year
Some round ponds and deep hollows in eastern Massachusetts mark spots where a block of ice, stranded and buried as the last glacier retreated, slowly melted away.
Why this time of year
Some kettle hollows are shallow enough to dry out every summer, and those are the ones that turn into vernal pools when winter and spring refill them.
How to notice it
- On your next walk, look for a small pond or a deep bowl-shaped hollow with a rounded rim.
- Stand at the rim and picture the hole filled by a single buried block of ice instead of air or water.
- Check nearby low spots too; a kettle hollow too shallow for a permanent pond can hold a spring vernal pool instead.
Try this with kids: Can you find the roundest pond or hollow on your next walk?
a kettle hole is a dent left where a buried block of glacier ice melted
Safety
- Never walk out on a frozen pond unless an adult has confirmed the ice is safe.
- Steep kettle rims can be slick with leaves; keep kids beside you at the edge.
Sources
- nps.govkettles form when a stagnant ice block detaches from the glacier, is buried in sediment, and slowly melts to leave a pit that often fills with water as a pond or lake
- nps.govkettle holes mark sites of ice blocks left by the retreating Laurentide ice sheet and buried by outwash; deeper depressions intersect the water table and hold ponds
- massaudubon.orgvernal pools across Massachusetts occur in kettle holes among other settings, tying the landform to eastern MA specifically