Geology
Mt. Philo is a well studied geological area, and is regularly visited by students at all levels. The Vermont Geological survey reports "The views of the Champlain Valley from the top of Mt Philo (elev. 968 ft) are exceptional. Much of the landscape has developed due to both erosion and deposition by glacial ice and meltwater. Vermont was heavily glaciated and once buried beneath ice. The glaciers carved away rock and ground it into finer grained sands and gravels, scoured valleys, and left behind rounded bedrock with grooves and striations. As the glaciers melted and retreated 12,000 years ago, ice dams and melting water formed lakes. Running water and melting ice deposited eroded material as deltas and moraines.
View south towards Snake Mtn.; hills are the upper plate of the Champlain Thrust.
Vermont was heavily glaciated and once buried beneath ice. The glaciers carved away rock and ground it into finer grained sands and gravels, scoured valleys, and left behind rounded bedrock with grooves and striations. As the glaciers melted and retreated 12,000 years ago, ice dams and melting water formed lakes. Running water and melting ice deposited eroded material as deltas and moraines. The materials deposited at the surface help explain the history and evolution of the landscape. As the glaciers retreated from Vermont, Mt. Philo was an island in an inland sea as evidenced by the marine sand deposits at its base. The State Fossil, the Charlotte Whale, is believed to have died in a shallow marsh of the Champlain Sea and been covered by fine clay sediment, providing more evidence for changes in climate and history of the Lake Champlain area. Yet all this activity is recent when compared with the 550 million year old bedrock of the Champlain Valley.
Wikipedia says "It sits atop the Champlain Thrust fault of Middle Ordivician age. It is made up of difficult to weather sedimentary rocks—the Cambrian Monkton Quartzites—that are thrust over younger Ordovician rocks of the Stony Point Formation. The rocks that hold up Mt. Philo were originally deposited during the Cambrian on a passive margin in a warm shallow marine shelf setting along the east coast of Laurentia (Proto North America). These rocks have subsequently been thrust west during the Taconic Orogeny (~450 Ma) and perhaps again during the Acadian Orogeny (~350 Ma).
The Cambrian and Ordovican sedimentary rocks of the Champlain Valley formed from sediment (sand, silt, carbonates and shells) deposited in shallow water along the continental margin in the Iapetus Ocean, a precursor to the Atlantic Ocean. The rock at the summit of Mt. Philo, also at Redstone Natural Area, is Monkton Quartzite. The oldest rocks are usually at the bottom of a deposit, but at Mt. Philo, the rocks at the summit are older than the rocks in the valley. The rocks moved up through the geologic section along faults.
Click to see a PDF of a Bedrock Geologic Map of Mt. Philo, Charlotte, VT
Wildlife
Birds and Hawk migration
Mt. Philo is famous for being along the migratory path of a wide variety of raptors. A large group of bird enthusiasts spend time on Mt. Philo in the spring and fall to observe these graceful creatures. Mt. Philo holds the state record for the largest number of migrating raptors seen in a single day, 3,688 seen on a single day. The peak of the hawkwatching season is the second and third week of September. Other highlights include:
30 bald eagles seen on 9/11/2010,
88 osprey on 9/16/1996,
3,522 broad wing hawks on 9/16/1993,
3,140 raptors seen on 9/10/2007.
Bryan Pfeiffer is a blogger, author, essayist, photographer, field guide and consulting biologist specializing in birds, butterflies and dragonflies. He writes:
Animals
Most Vermont native animals can be found on Mt. Philo. According to noted animal biologist, Laura Farrell bobcats and coyotes roam through the park on their daily rounds. Fisher cats are secretive, but have been regularly spotted. Red fox regularly have dens in easily accessible areas. Deer are plentiful on certain sections of Mt. Philo. Rabbits have had significantly increased numbers in the last 2 years, and our wild turkey population has also increased. Evidence of porcupines and raccoons are often found Pests include skunks and groundhogs, though neither is in great number. There are no poisonous animals or insects on Mt. Philo, and no bears. Red salamanders and mudpuppies are plentiful in the spring.
Birds and Hawk migration
Mt. Philo is famous for being along the migratory path of a wide variety of raptors. A large group of bird enthusiasts spend time on Mt. Philo in the spring and fall to observe these graceful creatures. Mt. Philo holds the state record for the largest number of migrating raptors seen in a single day, 3,688 seen on a single day. The peak of the hawkwatching season is the second and third week of September. Other highlights include:
30 bald eagles seen on 9/11/2010,
88 osprey on 9/16/1996,
3,522 broad wing hawks on 9/16/1993,
3,140 raptors seen on 9/10/2007.
Bryan Pfeiffer is a blogger, author, essayist, photographer, field guide and consulting biologist specializing in birds, butterflies and dragonflies. He writes:
"Get yourself to a mountaintop. The fall hawk migration is underway. Those first crisp, autumn winds are carrying waves of Broad-winged Hawks. They’re the abundant species now. But we’re also seeing Sharp-shinned Hawk, Cooper’s Hawk, Northern Harrier, American Kestrel, Bald Eagle, Osprey (pictured here) and a few others.
On clear days, as the sun warms air in the valleys, hawks in late morning and afternoon float skyward with rising thermals of autumn air. We call these circling masses of hawks “kettles;” they can number in the hundreds or thousands of birds. Once they rise to a sufficient elevation, the hawks break off and glide south. It’s a strategy to conserve energy for a long flight toward the tropics. So the hawk migration is, in part, solar-powered and wind-powered.
Mt. Philo in Charlotte and Putney Mountain are two of our best sites here in Vermont. In fact, after a moderate hawk flight on Mt. Philo on September 9, I had a bit of fun with my photo of hawkwatchers up there. What’s not right with this image?
Animals
Most Vermont native animals can be found on Mt. Philo. According to noted animal biologist, Laura Farrell bobcats and coyotes roam through the park on their daily rounds. Fisher cats are secretive, but have been regularly spotted. Red fox regularly have dens in easily accessible areas. Deer are plentiful on certain sections of Mt. Philo. Rabbits have had significantly increased numbers in the last 2 years, and our wild turkey population has also increased. Evidence of porcupines and raccoons are often found Pests include skunks and groundhogs, though neither is in great number. There are no poisonous animals or insects on Mt. Philo, and no bears. Red salamanders and mudpuppies are plentiful in the spring.