I strongly recommend discovering this earthcache at low tide only to avoid having to tresspass onto private property.
The tide tables are available here. tide tables
You should start your hike to the arch at the provided Depart/Start waypoint.
The following map shows the geology of the Dalhousie area.
About 12,000 years ago, northern New Brunswick was completely covered by ice during the last glacial maximum. As a result, most glacial deposits in the area are assumed to be Late Wisconsinan in age.The Last Glacial Maximum (LGM) refers to a period in the Earth's climate history when ice sheets were at their maximum extension, between 26,500 and 19,000 years ago, marking the peak of the last glacial period. During this time, vast ice sheets covered much of North America, northern Europe and Asia. These ice sheets profoundly impacted Earth's climate, causing drought, desertification, and a dramatic drop in sea levels.
The Sea Arch located here is a natural geological formation where a rock arch forms, with an opening underneath. Most natural arches form as a narrow ridge, walled by cliffs, become narrower from erosion, with a softer rock stratum under the cliff-forming stratum gradually eroding out until the rock shelters thus formed meet underneath the ridge, thus forming the arch. Natural arches commonly form where cliffs are subject to erosion from the sea, rivers or weathering (subaerial processes); the processes "find" weaknesses in rocks and work on them, making them larger until they break through.
Sea arches are formed when a land promontory is comprised of rock that varies in permeability. The more permeable sections of rock are more porous, and the action of the sea erodes these to a greater extent. Initially, caves form on either side of the promontory and gradually grow deeper until they coalesce to form an arch. A sea arch will continue to be eroded by waves, growing wider until it collapses
The choice between bridge and arch is somewhat arbitrary. The Natural Arch and Bridge Society identifies a bridge as a subtype of arch that is primarily water-formed. By contrast, the Dictionary of Geological Terms defines a natural bridge as a "natural arch that spans a valley of erosion."
The following schematic demonstrates how the Bon Ami Sea Arch may have formed.
To log this cache, e-mail the owner the answers to the following questions
-
How many other arches are there in the area?
-
What natural process causes a geological formation such as a cave to become an arch?
-
When standing in front of the arch, which direction are you looking towards ?
-
It would be appreciated but not required if the finders could post of picture of themselves and or there group close the GZ.
Thank you and I hope you enjoyed the geology lesson and the location.