The Department of Earth & Environmental Sciences, September 2021 Fall Field Trip took us to Ironbound Island on the coast of Maine. We chartered a boat to take us 3 miles off shore from Bar Harbor to the island, where we stayed in a rustic cabin. From there we did all-day hikes, enjoying the gorgeous scenery and investigating the rocks, structures, and landforms that make up the island.
Our first day took us around the southeastern shore of the Island from Seal Cove to Shag Ledge, where we investigated the rocks, structure’s, and landforms that make up the Island. Topics included island topography and geomorphology, joint systems and structural control of topography, marine highstand deposits and a “paleoford”, cliffs and glacial vs wave erosion, diorite sills and intrusive relationships with preexisting metasedimentary rocks, structure and depositional environment of Bar Harbor Fm metasedimentary rocks.
On our second day we investigated the north and west shores of the island, focusing on land use history and historical changes, an intrusive shatter zone and its relation to the geology of adjacent islands; boulder beaches, beach ridges and beach accretion vs erosion; historic shoreline retreat, and invertebrate tide pool ecology.
Our third day we worked on focused investigations of shoreline outcrops at the southern tip of the island, exploring (a) joint systems and relations to dike intrusion and topography; (b) intrusive relationships and interactions, including order of intrusive events and relationship of dikes to topography, and (c) glacial features, glacial versus wave erosion, and lithologic and structural controls on landscape and shoreline evolution.
Great scenery and great geology combined with great weather to make this an especially memorable trip for all participants!
