JUNE 02/2018 - SHETLAND ISLAND

Hello Geo folks,

Today the Capstone crew was in Shetland Island, studying the Shetland ophiolite. An ophiolite is a part of an oceanic crust that has been thrusted onto the continental crust, through a process called obduction. Shetland ophiolite was formed during the Ordovician period (480 million years ago) when the Iapetus ocean closed.


The team drove to Unst where the ophiolite is well exposed. As the team approached the outcrop, a herd of ponies, came running, hoping to be fed with snacks.




          A  beautiful moment of human-animal
           interaction.

The friendly ponies followed the team around as the team was trying to identify the ophiolite from the surrounding rocks and, according to Michael Rego, they were helping in identifying
the ophiolite (jokes folks). It wasn’t long before Ivano identified the boundary between dunite and harzburgite rocks which signifies the Mohorovicic discontinuity.
                                               From left; Michael, Thea, Lindsay,Caroline
                                               and Holly creating the word 'MOHO'
                                                   Photo credit: Charly Bank

No words could explain the excitement of these geonerds touching, hammering and observing the rocks that once lay several kilometers beneath the ocean, away from the reach of humans, and which carry so much information regarding the interior of the earth.


                                                      The sheeted dyke complex

The team also made a stop on trail 5 and at the beach where the sheeted dyke complex is exposed. Sheeted dyke complex represents the series of magma intrusions that fill the gap created when the sea floor was spreading.

                                           from Left; Zicky, Charly and Ivano standing on
                                           top of a sheeted dyke complex.

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