2 Massey University, Palmerston North, New Zealand ... has many volcanic geosites including the last historically erupted volcanoes in the Arabian Peninsula.
Cenozoic Magmatism in Central Europe 24th to 28th April 2013, Görlitz / Germany
Abstracts & Excursion Guides
Editors: Jörg Büchner VladislaV rapprich Olaf TieTz
Basalt 2013
Cenozoic Magmatism in Central Europe 24th to 28th April 2013, Görlitz / Germany Surface: Session 3c – Talks
The establishment of a volcanic geopark in the Kingdom of Saudi Arabia: Harrat Al Madinah Volcanic Geopark M. R. Moufti1 & K. Németh1, 2
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King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia Massey University, Palmerston North, New Zealand
Through the creation of a world network of natural parks with significant geological features, labeled UNESCO Geoparks, UNESCO promotes conservation of our geological heritage. Volcanic geoparks are increasingly popular projects worldwide and play a substantial role in geohazard education, including facilitating the dissemination of current research results on the volcanic processes that the ever increasing human society is faced with. Geosites, geomorphosites and geotops are the smallest “units” of intact geological features that are identifiable through their uniqueness or because they are graphic examples of specific volcanic phenomena or form a vital landscape representative of a specific volcanic processes. Here we identify significant volcanic features that bear not only regional, but global, volcanic value in a confined area that could be organized and promoted as the first volcanic geopark in the Kingdom of Saudi Arabia: the Harrat Al Madinah Volcanic Geopark. Harrat Al Madinah (“harrat” in Arabic means lava field) has many volcanic geosites including the last historically erupted volcanoes in the Arabian Peninsula. In addition, Harrat Al Madinah is located in a culturally significant place close to Al Madinah city (~ 1.5 million population), which is one of the holiest places to Muslims. The area is accessible through highways and in the near future by a train line linking Jeddah (the main port and air hub on the Red Sea coast) with Al Madinah. Overall, the proposed geopark would provide significant economic benefit to the city of Al Madinah. Pilgrims arrive from every corner of the globe, including countries where volcanic hazard is an everyday aspect of life (e.g. Indonesia); therefore, the proposed geopark would serve as a significant geoeducational hot spot. To begin with, a major geotop tentatively named as “The AD 1256 Al Madinah Historic Eruption Site” with distinct geosites/geomorphosites has been selected to demonstrate the diversity of volcanic phenomena associated with the intraplate volcanism of the Al Madinah Volcanic Field. Hawaiian to Strombolian type eruptions created lava spatter and scoria cones visible from major highways, allowing visitors to stop near the AD 1256 historic eruption site just 10 km SE of Al Madinah (Fig. 1). The 52 day-long eruption formed a ~2.25 km long NW-SE-aligned fissure, which emitted mainly alkali-olivine basalt (~0.5 km3) a’a lava flows (Camp at al. 1987) and formed fissure-aligned chain of lava spatter-dominated pyroclastic cones. At least seven vents have been identified, which made nested lava spatter and scoria cones. The central cones had more energetic explosive eruptive episodes that generated pyroclastic fall deposits, forming an ash-plain covering an area of about 10 km across. The vents are inferred to be hosted lava lakes. Lava lake outbreaks initiated crater wall collapses, as traced on circular fissures along the crater margins. The growth of the individual cones was repeatedly interrupted by lava flow outbreaks in the tip of the fissures by rafting away large pieces of the cones that were subsequently reheated, resulting in a nested and complex volcano morphology. This geotop is probably the best exposed and accessible site on Earth to show the diversity of volcanic features a fissure-eruption can produce. The recent increased seismic activity in 2009 in the region also justifies the establishment of an educational site that could play a significant role in the dissemination of scientific knowledge to the public, which could help the population better understand the potential outcome of any volcanic unrest the region may face.
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Basalt 2013
Cenozoic Magmatism in Central Europe 24th to 28th April 2013, Görlitz / Germany Surface: Session 3c – Talks
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Fig. 1. The historic eruption site of the Al Madinah AD 1256 eruption with proposed geosites.
References: • Camp V. E., Hooper P. R., Roobol M. J. & White D. L. (1987): The Madinah eruption, Saudi Arabia: magma mixing and simultaneous extrusion of three basaltic chemical types. – Bulletin of Volcanology, 49: 489–508.
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