Some pictures from our 2009 trip to Gibraltar - with "A Field Guide to the Geology of Gibraltar" by E P F Rose and M S Rosenbaum in my hand - not a comprehensive review of the local geology, just a look at the areas we visited
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| The "Pillars of Hercules" - the Atlas Mountains and the Rock of Gibraltar | Walking up Engineer Road - large areas concreted over for fire breaks |
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| Most of the Rock is the Jurassic Gibraltar Limestone Formation - here with blue pimpernel for scale; there is a rich profusion of plants on the Upper Rock | Caves on the Mediterranean Steps - there are numerous natural caves in the limestone - solution cavities, "sea caves" at former sea levels and man made tunnels (mainly by Royal Engineers) |
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| Looking north across the former water catchments, with Catalan Bay just apparent on the right, and the coast line going into Spain. Scree breccia evident above Catalan Bay | At top of steps - O'Hara's Battery - dip of bedding evident. The Main Ridge is overturned limestone, probably caused when the collision of the African and Eurasian plates pushed the Alboran microplate upwards and westwards |
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| Walking down from O'Hara's Battery - rocks along the road side | Just below St Michael's Cave - the tour bus driver's "Fossil bones" |
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| View across to the "Europa Pass" - now home to the Glen Rocky Distillery | North Face seen from Spain - scree breccia evident right of centre; (Quaternary) isthmus sands providing a base for the airfield |
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| Little Bay - outfall from the water desalination plant - folding in rocks to right of waterfall - looking north eastwards | Zoomed in to the rocks on the far (south) side of Little Bay - couldn't get near it to have a proper look |
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| Northern entrance to the Keightley Way Tunnel (General Keightley was the Governor for the first couple of years I lived in Gib) | Southern end of the Tunnel - eastern side wall |
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| Windmill Hill cliffs, seen from Europa Point (looking north) - folding evident behind the mosque | Further west from the previous photo - change in direction of bedding. This section of Gibraltar "right way up". Windmill Hill and Europa Flats are evidence of previous sea levels - wave cut platforms probably raised by tectonic uplift. |
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| North Face - coloration on rock face | Northern entrance to William's Way - when we lived in Gib, this was the only way to get through to Catalan Bay |
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| Southern entrance to William's Way - the tunnel curves round through the rock - currently it is closed to the public | This southern entrance to William's Way is cut through the youngest Mesozoic rocks on Gibraltar, the Catalan Bay Shale Formation - which underlies the overturned Gibraltar Limestone |
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| Catalan sands - windblown desert deposits above Caleta Palace Hotel | More sedimentary structures in the Catalan sands |
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| Looking across the Straits of Gibraltar - waves coming into the Mediterranean from the Atlantic | Interesting rock features just above Jew's Gate - pencil for scale - 15 cm |
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| Layered infill - coarsening downwards | Queen's Road - Bob's hand for scale |
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| Stromatolites and peloids - Queen's Road | Evidence of engineering work to make the roads - blasting in the rocks |
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| Some rocks had quartz veins within them - this had a layer of quartz on the surface | This was an exciting little exposure- quartz crystals like white and demerara sugar :-) |