Today we were on the beautiful island of #LaGomera this is an older #volcanic island with no activity for the last 2 million years with much of the rock exposure being Miocene 8-10 million years ago. The island is heavily eroded revealing columnar lava, dykes and felsic domes. Our first stop was the #RoquedeAgando a #trachyte dome that intruded around 5 million years ago (pic2). The rock is 220m high on the valley side and 100m high on the road side, and was an important religious site for the aboriginal peoples. Our next stop was to see #LaFortaleza (pic3) which is also a trachytic intrusion but with an unusual flat top, which may be to near surface ballooning, but the magma didn't break the surface. This site is also an important historically for the aboriginal because they took refuge there during the Spanish conquest. We then moved on to Valle Gran Rey where we took a boat tour to see the incredible cooling columns of #LosOrganos (pic 1 & 4-6). These columns are actually trachyte not basalt (as cooling columns commonly are) and are situated in an eroded trachyte dome. After lunch we stopped for a view over the Valle Gran Rey and could see horizontal Pliocene basalts resting uncomformably on dipping Miocene basalts (pic7). This was followed by Garonjay National Park which is also a #WorldHeritageSite on account of its subtropical laurel cloud forest (pic8). This was following by a former quarry which contains beautiful red tuff that has been baked solid by an overlying lava flow, and is also cut by basaltic dykes (pic9). This tuff is used as building stone throughout the island. Our final stop was a huge dyke that was about 5m across and contained cooling structures (pic10). (at La Gomera, Islas Canarias) https://www.instagram.com/p/B6GzMmLpxtI/?igshid=1txm263ueq5v4
