The origin of sandstone boulder aprons along the escarpments of the Stołowe Mountains: are they all rockfall-derived? A new insight into an old problem using the CONEFALL 1.0 software

Abstract

Abstract.A characteristic feature of sandstone-capped escarpments in the Stołowe Mountains is the occurrence of extensive boulder mantles which extend from the rock face to the footslope over distances of 300-500 m. The hypothesis implying rockfall as the process of boulder release from the rock face and subsequent transport is tested by means of Conefall 1.0 software, designed to simulate run-out zones of rockfalls. The actual extent of boulder mantles is much larger than the simulated extent, which casts doubt on the applicability of rockfall scenario. Alternative hypotheses are briefly discussed and it is concluded that a similar morphological effect can be achieved by in situ caprock disintegration and sub-caprock slope lowering and retreat.

Understanding rockfalls along the national road G318 in China: from source area identification to hazard probability simulation

“…Besides, the rockfall trajectory path is determined by important input data, the reach angle (Wieczorek et al, 1998;Guzzetti et al, 2003;Jaboyedoff and Labiouse, 2003;Frattini et al, 2008;Matasci et al, 2015). The reach angle is also known as travel angle or travel distance angle (Copons et al, 2009;Duszyński et al, 2015), controlling rock fragments' probability and energy along the pathway. It is the arctangent of the line which connects the rockfall source area with the most distant boulder (Figure.4,Eq.3).…”

Evolution of sandstone mesas – following landform decay until death

“…Altitude reaches 919 m ASL on top of the Mount Szczeliniec Wielki mesa. The escarpments are covered by extensive mantles of sandstone boulders, extending hundreds of meters away from the cliff lines (Duszyński and Migoń, 2015, Duszyński et al, 2015). Among minor landforms of particular interest in the context of this study are two isolated boulder fields, located within the nearly level surfaces of the main plateau of the Stołowe Mountains (Pustelnik and Rogowa Kopa localities).…”

“…On the contrary, our understanding of processes responsible for long-term escarpment retreat has improved significantly in the recent years. New data and observations allowed one to suggest that escarpment retreat in the Stołowe Mountains is mainly the result of noncatastrophic in situ disintegration of sandstone cliffs (Duszyński and Migoń, 2015; Duszyński et al, 2015, 2016).…”

Boulder Fall Activity in the Jezero Crater, Mars

“…We used the empirical shadow angle method (Evans & Hungr, 1993; Lied, 1977) to analyze the runout distance of boulder falls on the delta deposits. Shadow angle is the angle between the horizontal line from the talus apex and the line that connects the talus slope apex with the most distant boulder fall (Duszyński et al, 2015). Please see Supporting Information S1 for details on the data and methods.…”