This cache exists with permission of the Massachusetts Department of Conservation and Recreation (DCR). In accordance with DCR rules, please stay on existing trails and tread lightly. Alteration of landscape or vegetation through blazing or bushwhacking may lead to the deactivation of this cache. Thank you!
Mount Greylock is the tallest mountain in Massachusetts, measuring 3,491 ft (1,064 m) above sea level. Between 600 to 450 million years ago, the older phyllite and schist metamorphic rock formations of the Taconic Range to the west are believed to have been thrust up and folded over on top of the younger limestone and marble sedimentary rock of the Hoosac Valley to the east, forming this mountain group.
Metamorphic rock
common to the west of Mount Greylock |
Sedimentary & metamorphized sedimentary rock
common to the east of Mount Greylock |
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| Phyllite |
Schist |
Limestone |
Marble |
At one time, Mount Greylock was perhaps 20,000 feet in height; however, it has been reduced to its present size by eons of constant erosion. About 18,000 years ago during the Pleistocene Epoch, the entire Berkshire region was covered by a kilometer-thick sheet of ice. As this sheet of ice melted and receded, a valley glacier (example to the left) formed to the northwest of the Mount Greylock peak.
This valley glacier, which provided drainage for the ice fields, was constrained by the tall mountain peaks on three sides. Because there was only one exit for the ice melt (and associated erosion material), a cirque was formed.
A cirque is an amphitheater-like valley: three of its sides have steep slopes and one side is open. The cupped section is generally steep, with cliff-like slopes down which waterfalls may form. The cirque on Mount Greylock is known as "The Hopper" and is the southernmost such glacial feature in New England. Below you can see The Hopper cirque, with its opening on the west, surrounded by the inverted-C shape of Mounts Prospect, Williams, Fitch, Greylock, and the Stony Ledge:
© OpenStreetMap contributors
Among the many small streams trickling down the sides of the amphitheater into the valley, the Hopper has two main waterfalls. Money Brook Falls is in the northern section of the Hopper cirque, which can be approached from the Money Brook Trail. The southern section has the March Cataract Falls, which is where you are standing. The two waterfalls eventually join to create the Hopper Brook in the valley. It should be noted that March Cataract Falls is considered a seasonal waterfall, and can reduce to a trickle during the summer dry months. However, it does not take much rainwater to get the 30′ falls going.
To log this EarthCache, please include the following information in a message to me (DO NOT post the answers in your log):
- The ID and title of this geocache (GC5966W: The Hopper Cirque)
- Of what type of rock is the cirque wall behind March Cataract Falls primarily composed—phyllite, schist, limestone, or marble?
- Based on the rock type from question two above, does this indicate that Mount Greylock is more geologically similar to the Taconic Range to the west or the Hoosac Range to the east?
- The stream below the falls marks the southern border of The Hopper cirque. The stream flows fairly straight at this location. Using your GPS, determine what direction (to the nearest 5°) the stream flows away from the falls.
- OPTIONAL: Please post a photo of you at March Cataract Falls with your log. It would be great to see how the waterfall flow changes with the seasons.
Mount Greylock State Reservation is open year-round from sunrise until dusk for day-use recreation. Overnight camping and accommodations are permitted only at the Mount Greylock Campground, the five designated backpacker shelter areas, and on the summit at Bascom Lodge, May-October. The auto road to the summit is open from late-May through November 1. Please respect all posted rules, regulations and speed limits. More info at http://www.mass.gov/eea/agencies/dcr/massparks/region-west/mount-greylock-state-reservation-operating-hours-and-se.html
Sources:
- Burns, Deborah E. and Stevens, Lauren R., Most Excellent Majesty: A History of Mount Greylock, Pittsfield: Berkshire Natural Resources Council, Inc., 1998. Print.
- Parsons, Greg and Watson, Kate B., New England Waterfalls: A Guide to More Than 400 Cascades and Waterfalls, Woodstock: Countryman Press, 2010. Print.
- "Mount Greylock State Reservation," MassParks, Executive Office of Energy and Environmental Affairs, Department of Conservation and Recreation. Web. July 19, 2014.
- "Natural History of the Berkshires," Williams College. Web. July 19, 2014.