What are we looking at here? This is what I think at the moment. [I am still doing some research into the totally unfamiliar geology of the Canadian Atlantic Maritime Provinces, so this is all a learning process for me]. I believe these photographs show a typical example of the type of rock from which the multi-coloured and patterned pebbles on the beach are derived (see the earlier post Pebbles at Saints Rest Beach).
A free-standing large boulder sits in the beach sand and gravel close to the outcropping bedrock of the headland to the west of Saints Rest Beach. It is very different in all regards to that solid bedrock. It stands separately, over a metre high and diameter above the beach surface. It is a composite rock with rough, sharp pieces of a range of rock types that vary widely in size, shape, and composition. These ill-assorted rocks are contained within, and inter-bedded with, much finer red sediments and clays, in a seemingly random way.
I believe the boulder to be, geologically speaking, relatively recent material from the last Ice Age. I know from looking at geological maps of the area that glacial moraine covers vast areas of bedrock in this region. In The Stonehammer Geopark website article entitled A Billion Years of Stories it says
The Neogene or Quaternary geological history of the area is recorded as late-glacial and postglacial sediments from the Last Glacial Maximum about 20,000 years ago to the present. Moraines, glacial outwash deposits, striated bedrock, glacial till, and raised shorelines are all seen in the park (Stonehammer Geopark). In the Irving Nature Park one of the best regional records of the last ice age is seen at Saints Rest Beach where a tidewater glacier left glacial outwash interfingering with marine clays….
I am wondering if the boulder I photographed shows these glacial outwash materials with interspersed layers of marine deposits; or possibly the soft red clays are part of the glacial outwash as well…but I could be wrong and welcome comments from the more knowledgeable in these matters.
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