The cycle of instability: stress release and fissure flow as controls on gully head retreat

2001 ◽  
Vol 15 (1) ◽  
pp. 3-12 ◽  
Author(s):  
A. J. C. Collison
Keyword(s):  
2021 ◽  
Vol 111 ◽  
pp. 102673
Author(s):  
Liangbi Li ◽  
Jingxi Zhang ◽  
Yiwen Zhang ◽  
Deqin Zhu ◽  
Zhengquan Wan ◽  
...  

2019 ◽  
Vol 7 (4) ◽  
pp. 929-947 ◽  
Author(s):  
Michele Delchiaro ◽  
Marta Della Seta ◽  
Salvatore Martino ◽  
Maryam Dehbozorgi ◽  
Reza Nozaem

Abstract. The Seymareh landslide, detached ∼10 ka from the northeastern flank of the Kabir-kuh fold (Zagros Mts., Iran), is recognized worldwide as the largest rock slope failure (44 Gm3) ever recorded on the exposed Earth surface. Detailed studies have been performed that have described the landslide mechanism and different scenarios have been proposed for explaining the induced landscape changes. The purpose of this study is to provide still missing time constraints on the evolution of the Seymareh River valley, before and after the emplacement of the Seymareh landslide, to highlight the role of geomorphic processes both as predisposing factors and as response to the landslide debris emplacement. We used optically stimulated luminescence (OSL) to date lacustrine and fluvial terrace sediments, whose plano-altimetric distribution has been correlated to the detectable knickpoints along the Seymareh River longitudinal profile, allowing the reconstruction of the evolutionary model of the fluvial valley. We infer that the knickpoint migration along the main river and the erosion wave propagation upstream through the whole drainage network caused the stress release and the ultimate failure of the rock mass involved in the landslide. We estimated that the stress release activated a mass rock creep (MRC) process with gravity-driven deformation processes occurring over an elapsed time-to-failure value on the order of 102 kyr. We estimated also that the Seymareh damming lake persisted for ∼3500 years before starting to empty ∼6.6 ka due to lake overflow. A sedimentation rate of 10 mm yr−1 was estimated for the lacustrine deposits, which increased up to 17 mm yr−1 during the early stage of lake emptying due to the increased sediment yield from the lake tributaries. We calculated an erosion rate of 1.8 cm yr−1 since the initiation of dam breaching by the Seymareh River, which propagated through the drainage system up to the landslide source area. The evolutionary model of the Seymareh River valley can provide the necessary constraints for future stress–strain numerical modeling of the landslide slope to reproduce the MRC and demonstrate the possible role of seismic triggering in prematurely terminating the creep-controlled time-to-failure pathway for such an extremely large case study.


2021 ◽  
pp. 100799
Author(s):  
Hao Luo ◽  
Bo Wang ◽  
Jiahuang Jian ◽  
Fangdong Wu ◽  
Li Peng ◽  
...  

CATENA ◽  
2021 ◽  
Vol 207 ◽  
pp. 105674
Author(s):  
Rui Wang ◽  
Peng Li ◽  
Zhanbin Li ◽  
Kunxia Yu ◽  
Jianchun Han ◽  
...  

2021 ◽  
Vol 16 (05) ◽  
pp. 42-45
Author(s):  
Ulrike Balke-Holzberger
Keyword(s):  

SummaryDie Faszien-Stress-Realease-Arbeit (FSR-Arbeit) basiert auf den drei Säulen: Körperübungen, neurogenes Zittern und Körperachtsamkeitsübungen.


Marine Drugs ◽  
2018 ◽  
Vol 16 (7) ◽  
pp. 237 ◽  
Author(s):  
Ana Seca ◽  
Diana Pinto

Hypertension and obesity are two significant factors that contribute to the onset and exacerbation of a cascade of mechanisms including activation of the sympathetic and renin-angiotensin systems, oxidative stress, release of inflammatory mediators, increase of adipogenesis and thus promotion of systemic dysfunction that leads to clinical manifestations of cardiovascular diseases. Seaweeds, in addition to their use as food, are now unanimously acknowledged as an invaluable source of new natural products that may hold noteworthy leads for future drug discovery and development, including in the prevention and/or treatment of the cardiovascular risk factors. Several compounds including peptides, phlorotannins, polysaccharides, carotenoids, and sterols, isolated from brown, red and green macroalgae exhibit significant anti-hypertensive and anti-obesity properties. This review will provide a comprehensive overview of the recent advances on bioactive pure compounds isolated from different seaweed sources focusing on their potential use as drugs to treat or prevent hypertension and obesity. On the other hand, although it is obvious that macroalgae represent promising sources of antihypertensive and anti-obesity compounds, it is also clear that further efforts are required to fully understand their cellular mechanisms of action, to establish structure-inhibition relationships and mainly to evaluate them in pre-clinical and clinical trials.


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