Spent the morning herding cats at Malaga Airport but by lunchtime we had 20 people and their luggage in six cars and headed west to a lunch stop at Arroyo de la Miel services on the AP7. This also served as the first geology stop as there is coarsely crystalline marble exposed in the cutting at the back.
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| Coarsely crystalline marble at Arroyo del Miel - part of the "Alboran Block" |
On westward to San Pedro de Alcantara, then up the A 397 to Ronda, taking in a couple of stops on the way.
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| Road cut in peridotite at Km 34 on the A397 |
At km 34 we were on peridotite, vegetated by pine trees and saw plenty in situ. A second rock type, stretched, flattened, and with foliation and augen that showed refolding comes from under the peridotite sheet. There were also breccias: what Tom called a magmatitic breccia, with blobs of quartz and lithic clasts; some black granular patches on faces could be chromite or spinel, a mass of small crystals.
Loose bits of carbonate are probably quarried.
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| Stuart with a metagranite cobble from the roadside |
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| Metagranite with post-kinematic augen |
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| Intricately strained and folded metabreccia |
The breccia pebbles look waterworn. ? Transport, ? Reworking. One had post kinematic garnets.
This is an odd road: it was upgraded in the 1970s to serve the burgeoning tourist industry on the Costa del Sol, providing an easy route up to Ronda from the coast for the tourist excursions. It climbs steadily up through the Sierra Bermeja but doesn't go through any towns or villages! I checked an old (1966) map of Spain and the, then, C (minor) road is marked as a "slow road: tight curves and steep slopes only permit a reduced speed". I love this old map - it dates from a family holiday in Spain in that year and has so many roads marked with the red crosses that Michelin used to denote a "road in a bad state".
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| View NW from Km 24.5 towards the peridotite/limestone junction - where the pine trees stop! |
We stopped again at Km 24.5 where there is a view of the northern contact of the S Bermeja peridotite with a grey rock, limestone, to the north. This is the Dorsale Limestone of the Serrania de Ronda. Its steep contact with the peridotite is indicated by the straight junction at surface.
The junction itself is by km 20: we visited this later in the week but following early starts that morning it seemed a good idea to push on into Ronda and get checked in to our hotel!
Hotel Don Javier is right in the centre, but easy enough to find as it is just off the main street, across the Puente Nuevo. Unloading (and loading up/unloading on the following days) needed some good organisation as the unloading area was the taxi rank by the bull ring, reached by going through a "no entry" sign and only 10 minutes allowed on each occasion. Then the hotel concierge had to nip down to open the underground garage, where he very kindly parked and unparked the cars for us! Probably a good thing as it was a very tight fit :(
On this first evening we identified a convenient bar, which no one but us seemed to be using, just across the alley from the hotel, and took that over on the next five evenings for our "debrief" sessions. The big G and T's they poured certainly hit the spot with some of the group!
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