SW4338 : Gurnard's Head - Volcanic sheets and sediments

taken 4 years ago, near to Porthmeor, Cornwall, Great Britain

Gurnard's Head - Volcanic sheets and sediments
Gurnard's Head - Volcanic sheets and sediments
The 'massive' (meaning featureless) basic volcanics (basalts) can be seen to the top, lower right and lower left (hammer). Deep marine sediments of the Gramscatho basin can be seen surrounding the volcanic intrusion of which the hammer sits on. To the right of the hammer a disarticulated blob can be seen, it seems to have been left behind and ripped off the parent intrusion. This paints a scene of deep hot black basalt intruding the soft sediments. I think some small peperitic textures can be seen locally (not on this picture).

The sediments and volcanics can be told apart due to a couple of reasons.
The volcanics are a granular crystalline blue colour (altered due to their age and metamorphism, regional and thermal). The sediments have developed a local cleavage due to the presence of platy minerals (the flat minerals alight perpendicular to the principle stress direction).
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SW4338, 51 images   (more nearby )
  (find more nearby)
Date Taken
Saturday, 28 September, 2013   (more nearby)
Sunday, 29 September, 2013
Geographical Context
Geological interest 
Subject Location
OSGB36: geotagged! SW 4323 3859 [10m precision]
WGS84: 50:11.4917N 5:35.9277W
Camera Location
OSGB36: geotagged! SW 4322 3857
View Direction
North-northeast (about 22 degrees)
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