Even more retrospectively!
In between writing the first part, and starting this, we've pack up, sold up, and moved to France, so now I'm trying to pick up the threads some 6 months after Part 1, and 10 months after the trip!
Picking up where I left off in April, we carried on from the mirador at Morro Veloso to the Rio de Vega where we walked down the barranco to examine ring complex exposures (see previous trips) and then along the road above, stopping at miradors.
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| A pipit? |
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| The information board above Las Penitas dam |
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| A raven at the mirador |
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| Walking up onto the syenite tor above the mirador |
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| The syenite ridge |
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| Agricultural roundabout |
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| A reminder that Christmas is just around the corner! |
Ajui 15 December
This is a favourite day, when we walk up the barranco south of the little ex-fishing village to look at the island's ultramafic roots and seamount evidence.
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| Submarine lava cut by a dyke (bottom left) and zones of migmatisation |
There is submarine lava, with pillows, near the entrance to the barranco just south of the village.
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| Basalt, dykes and migmatite |
Migmatised ultramafic rock is cut by basalt dykes
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| Zebra rock - the distinctive migmatite texture found here |
I really want to know more about the texture and mineralogy of this migmatite - the leucosomes show preferential orientation(s) and have dark edges - depleted melanosome? Plus there are porphyroblasts (or are they restite phenocrysts?) Looking forward to having time to make a thin section of it for myself. Meanwhile I have to rely on information (Woodcock, 2007) that the leucocratic veins are made up of plagioclase feldspar with some smaller grains of clinopyroxene, a brown pleochroic amphibole and an opaque mineral. The finer grained melanosome is clinopyroxene, brown amphibole and opaques. The larger individual grains are cpx, "probably" restite phenocrysts.
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| Ajuy beach from the south |
When you get back from the barranco there's a fantastic view north up the beach to the cliff at the far end which is submarine seamount series with loads of dykes at the base, then that is planed off with submarine sands planar bedded on top.
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| Barranco de la Solapa |
Heading back inland and turning south in Pajara there's a stop by a road cut where the seamount series are exposed without the benefit of wave washing.
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| The col between Fayagua and Chilagua |
There are stunning views in all directions from this col, and from the hilltop viewpoint a short walk away.
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| Parking at the col - popular with tourists |
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| Below the viewpoint (top right) there are lots of dykes cutting across the hillside |
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| Ravens hoping for picnic crumbs |
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| A good place for a group photo at the end of the trip! |
After seeing most of the group members off the next day, I stayed on for a little longer as I wanted to check out some ideas for a project.
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