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When dinosaurs roamed the Western Isles
Quite a challenge, I expect, to the local Free Presbyterians.
My friend Kim Johnson commented on the strange appearance of the footprints, Steve Drury (author of the blog of which this is just an annotated repost) referred me to Paige Depolo, senior author of the paper on which Steve’s post is based, and Paige replied as follows:
When it comes to the depositional environment, the tracks were formed in a low-energy lagoon and are generally preserved today as impressions into shaley limestone. Later, additional limestone layers were laid down at the site and in-filled the impressions. Those layers form the casts that we can still observe for some of the tracks today. In some cases at this site, the cast remains while the surrounding impression which it was originally infilling has been almost completely eroded. These rocks were deposited during the Middle Jurassic. Later, likely during the Paleogene, a sill was intruded immediately below the track bearing layer and the surrounding rocks were baked. The low-level contact metamorphism of the track-bearing layers definitely makes for some interesting looking exposures!
h/t Kim and Steve, and many thanks to Paige
Cuillin Hills, Isle of Skye, Scotland, UK (credit: Wikipedia)
The Isle of Skye off the northwest coast of Scotland is known largely as a prime tourist destination, such as Dunvegan Castle with a real clan chief (The MacLeod of MacLeod) and its Faerie Flag; Britain’s only truly challenging mountains of the Black Cuillin; and, of course, the romantic connection with the Young Pretender, Charles Edward Stuart and his escape, in drag, from the clutches of the Duke ‘Butcher’ Cumberland, hence the Skye Boat Song. Geologists know it best for its flood basalts with classic stepped topography and the exhumed guts of a massive central volcano (the Cuillin), relics of the Palaeocene-Eocene (62 to 54 Ma) North Atlantic Large Igneous Province. The spectacular Loch Coruisk, a glacial corrie drowned by the sea, exposes the deepest part of the main magma chamber. It is also the lair of Scotland’s lesser…
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