The Department of Geosciences September 2017 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.

On our first day we explored island topography and geomorphology along the southeast shore, including joint systems and structural control of topography, marine highstand deposits and a paleofjord that splits the island, seacliffs and glacial vs wave erosion, a massive diorite sill and intrusive relationships with preexisting metasedimentary rocks, and the 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 joint systems and relations to dike intrusion and topography; intrusive relationships and interactions between various generations of dikes and the enclosing diorite; and glacial features and sea level 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!

October 4, 2017