Very down-to-earth Vasquez rocks portray the surface of alien planets for the media

Deborah Painter (USA) They have become associated with stark alien or other-dimensional landscapes since the 1960s, when the popular American television programme Star Trek used them as dramatic backdrops in two episodes, “Arena” and “Friday’s Child”. Prior to that, the Vasquez Rocks of Agua Dulce in California were a favoured location for American Western programmes, such as Branded, Cheyenne, Zorro and The Adventures of Champion, as well as motion pictures like One Million BC (1940) and Apache (1954), when rocky areas with hiding places, wide overlooks and an overall arid, rugged look were needed. More recent films and television programmes tend to exploit their odd appearance (Star Trek IV: The Voyage Home (1986), Army of Darkness (1993) and John Carter (2012)). Some films with no fantasy elements also use the rocks as a backdrop, one example being the family “road” comedy, Little Miss Sunshine, released in 2006. Fig. 1. The much-photographed side of the Vasquez Rocks pinnacle and main film staging area. (Photo: Michael Ramsey.) In fact, the Vasquez Rocks now have the distinction of being an overexposed outdoor location simply because of their proximity to the big city of Los Angeles’ filmmaking industry, hence their presence in scores of films, television programmes and music videos. Only about 64.5km from Los Angeles, the Vasquez Rocks are off State Highway 14, between Acton and Santa Clarita in California, USA and can be seen from Highway 14. The signs will direct the motorist to the exit that leads to the Vasquez Rocks … Read More

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Triassic salt in the High Atlas of Morocco

Chellai El Hassane (Morocco), Ghanmi Mohamed (Tunisia) and Doblaas Miguel (Spain) The Triassic terrestrial deposits at the northern edge of the High Atlas near Marrakech are mainly represented by thick sequences of massively layered, red sandstone. These are topped by a formation of silt and pink-brown clay containing large deposits of evaporites consisting mainly of rock salt and gypsum. The silt and clay formations form domed structures characterised by intruded gypsum and irregular (disharmonic) folds capped by fine sandstone beds, as well as by small, isolated anticlines only a few metres in scale. The direction of folding shows no relationship to that of the major tectonic folding that gave rise to the Atlas Mountains. In contrast, the folding is closely linked to the deposition of rock salt and gypsum in the High Atlas near Marrakech during the Late Triassic. The same phenomenon is observed in the passive margins of the Atlantic of western Morocco. Lithostratigraphy These Triassic formations are the most prominent features of the landscape, with thicknesses that can reach up to 400m. They consist essentially of two formations: F5 (the Oukaïmeden sandstone) and F6 (the Superiors Silts), which correspond to the uppermost part of the Triassic, as defined in the Ourika valley by Biron (1982). The first formation consists of thick (400m) beds of detrital sandstones with fine to medium-sized, diamond-shaped sedimentary bodies, interbedded with layers (a few centimetres to several metres thick) composed of red clay as well as red and brown silts. These are overlain by … Read More

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Can the end-Permian mass extinction be attributed to a single, catastrophic event?

Robert Broughton (UK) The end Permian mass extinction occurred 251mya and marked the end of the Palaeozoic era. The loss of life is currently estimated to consist of 95% of the marine fauna and around 70 to 77% of the known terrestrial fauna (where the fossil record is inevitably less complete). This article will provide an overview of the many events and processes that played a part and a discussion whether they can all be attributed to a single, root cause. Reef evidence At this time, the landmass was united into the single, super-continent of Pangea, surrounded by warm shallow seas with abundant reef systems. This extensive reef fauna supported a variety of suspension feeders (for example, crinoids, rugose and tabulate corals, and so on), which were the most heavily hit by the extinction event, with all the known corals dying out. Modern scleractinian corals only appeared in the Triassic and there is a considerable gap in the coral fossil record at this time. Other reef inhabitants, such as the last phillipsid trilobites also became extinct. All these creatures were sessile or relatively immobile inhabitants of the reefs that occupied a relatively narrow zone on the continental shelf. This habitat must have been destroyed almost globally by a number of factors, but importantly, the single shelf margin around Pangea meant there was no other shallow reef environment for the fauna to migrate to. Fig. 1. Reef evidence. Tectonic activity The single continent of Pangea was always doomed to split apart. … Read More

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