Landform effect on rockfall and hazard mapping in Cappadocia (Turkey)

Abstract

The Cappadocia region has unique geomorphological features resulting from differential erosional processes which make it very attractive to tourists. Besides the fairy chimneys for which the area is best known, there are also impressive buttes and mesas. Buttes and mesas are formed in regions having flat-lying strata in which the uppermost levels are composed of well-cemented limestones and granular ignimbrites, whereas the lower parts and slopes consist of low-durability tuff and ignimbrites. This durability difference results in serious rockfall events. This study involves two-dimensional rockfall analyses in and near the Avanos, Zelve, and Ç avusini areas, where volcano-sedimentary units of Neogene age outcrop, to provide a rockfall hazard map in which areas of tourism activity are also considered.

Rockfall at the heritage site of the Tatlarin Underground City (Cappadocia, Turkey)

“…Engineering geological problems of the Cappadocia region were investigated by many researchers (Doyuran 1976;Topal and Doyuran 1997;Aydan et al 2007;Ulusay et al 2006;Tunusluoglu and Zorlu 2009;Tuncay 2009;Zorlu et al 2011). According to these studies, the major geological problems of Cappadocia include the possible failure of roofs of caves and rockfalls.…”

“…Other examples of cultural heritage in tuffs and ignimbrites include some of the Buddha statues in Japan (e.g., Heiwa-Kannon statue, Oguchi and Yuasa 2010), the Moai statue in the Easter Islands (Gioncada et al 2010), the Macusani rock art site in Peru (Hostnig 2008), the underground cities of Vardzia in Georgia (Tutberidze and Tsutsunava 2015;Margottini et al 2015) and Kandovan in Iran (Kaljahi and Birami 2015), and the rock-hewn churches of Lalibela in Ethiopia (Delmonaco et al 2005;Renzulli et al 2011). In Turkey, apart a few exceptions (Binal and Ercanoglu 2010;Topal et al 2007Topal et al , 2012, the majority of engineering geological studies on instabilities at the heritage sites are concentrated in Cappadocia (Doyuran 1976;Aydan et al 2007;Ulusay et al 2006;Tunusluoglu and Zorlu 2009;Tuncay 2009;Zorlu et al 2011;Kaşmer et al 2013).…”

“…Rockfalls in Cappadocia are favoured by the weakness of Miocene-Pliocene tuffs and by differential erosion due to the interbedding of lithological units with different durability (Zorlu et al 2011). High durability units, such as basalts or welded tuffs, protect the underlying weaker units (tuffs, ignimbrites), giving rise to tall, thin fairy chimneys and subvertical cliffs from which rockfalls can occur.…”

“…Rockfall hazard has been studied in Cappadocia (Ulusay et al 2006;Tunusluoglu and Zorlu 2009;Zorlu et al 2011) by using two-dimensional rockfall simulations, thus neglecting the convergence and divergence of trajectories and the lateral spreading of the blocks during propagation (Frattini et al 2012) with a possible under or overestimation of the hazard at the various localities.…”

Engineering Geology for Society and Territory - Volume 8

“…Engineering geological problems related to rock mass instabilities of historical heritages in Cappadocia have been investigated by many researchers (Doyuran 1976;Aydan and Ulusay 2003;Ulusay et al 2006;Tunusluoğlu and Zorlu 2009;Zorlu et al 2011). The Cappadocia Region mainly consists of Pre-Miocene basement rocks, Lower Miocene sedimentary rocks (red mudstone, sandstone, and conglomerates), Miocene volcanosedimentary unit (Ürgüp Formation) and volcanic rocks (ignimbrite, andesite and basalt) of Neogene-Quaternary period (Temel et al 1998) (Fig.…”