Geology of the National Parks



This week, we feature four GeoClips, all created while Dr. Alley was on vacation at the Cape in the summer of 2005. These four "home movies" provide a bit of insight into the origins of the Cape, and the forces that are continuously at work changing our coasts, shorelines, and seas. Shooting and editing credits go to Dr. Alley's wife, Cindy.

As before, we hope you enjoy these, and find them to be useful complements to the readings, class notes, and slide shows of Unit 8.

The Can

Human impacts on the land are easy to see. We have changed the oceans greatly, but the water covers our tracks. In "The Can," Dr. Alley briefly reflects on some issues of the oceans, as he watches one of the less-beautiful pieces of the Cape Cod National Seashore.

The Marsh

Many of the ocean’s big fish, and other denizens of the deep, rely on salt marshes as nurseries and in other ways. But, we are losing salt marshes in many places, as sea-level rise forces the “outer beach” toward the shore, but humans don’t allow the inner side of the marsh to expand into our yards or parking lots. Obvious answers are not easily available, but Dr. Alley frames the question in this next short film clip as he paddles one of the family kayaks on the Nauset Marsh of the Cape Cod National Seashore.

The Feet

Waves move immense amounts of sand, primarily up and down the beach, but also with a little motion along the beach and eventually off into deep water. In "The Feet," Dr. Alley gets cold feet on Coast Guard Beach, Cape Cod National Seashore, to show you moving sand.

Meet Peat!

Cape Cod is a gift of the glaciers. The numerous kettle ponds left by the ice contribute to the biodiversity of the Cape, but are slowly filling in with sand, peat, and other things. Many of the ponds have already filled, and a walk along the rapidly eroding outer beach often reveals where the sea has cut into one of these filled ponds. In this next clip, Dr. Alley shows one such exposed, filled kettle pond, just below the old Coast Guard station in the Nauset region of the Cape Cod National Seashore.