Spatial distribution of dolines as an indicator of recent deformations on the Velebit mountain range (Croatia)/La répartition spatiale des dolines comme indicateur de contraintes tectoniques. Montagne de Velebit (Croatie)

1999 ◽  
Vol 5 (2) ◽  
pp. 129-142 ◽  
Author(s):  
Sanja Faivre ◽  
Philippe Reiffsteck
Landslides ◽  
2021 ◽  
Author(s):  
Suman Panday ◽  
Jia-Jyun Dong

AbstractContinuous 5-day (August 4–9, 2019) torrential rainfall in the monsoon season triggered more than 90 landslides on northwest-southeast extended mountain range of Mon State, Myanmar. In this study, remote sensing images, DEM, and limited fieldworks were used to create the landslide inventory. The topography features of these landslides are analyzed via ArcGIS. The largest one occurred on 9 August 2019 and caused 75 deaths and 27 buildings were damaged. This landslide occurred on gentle topography (slope angle, 23°) with long run-out, in which the angle of reach was relatively low (10°). The volume was 111,878 m3 was mainly composed of weathered granite and red soil and the sliding depth was approximately 7.5 m. Topographic characteristics including the relative slope height, angle of reach, and slope angle of source area of 35 landslides with areas > 4000 m2 were analyzed. The spatial distribution characteristics and topographic features of the 35 landslides below are distinguished: (1) the concentration of most of landslides on southwest-facing slopes showing the heterogeneous spatial distribution of landslide; (2) an uncommon landslide distribution in which more than half of landslide originates from upper slope; (3) the range of the angle of the source area (17°–38°) compatible with the internal friction angle of soils in tropical regions (17°–33°); and (4) the tangent of the angle of reach is generally smaller than 0.5 (angle of reach < 27°) shows a relative high mobility and the relation between landslide mobility and the slope angle of the landslide source area is similar to the one of earthquake-triggered landslides, even though the triggering mechanism, landslide type, and landslide volume are dramatically different.


Author(s):  
Zhanbing Ren ◽  
Yifan Zuo ◽  
Yudan Ma ◽  
Mu Zhang ◽  
Lee Smith ◽  
...  

Purpose: The purpose of this study was to investigate the influence of natural environmental factors on the spatial distribution of marathon events in China, and to identify the suitable natural environmental factors for the marathon events. Methods: Geographic information system (GIS) spatial analysis tools were used to perform coupling analysis, e.g. overlap, neighborhood, intersection and buffer for terrain, climate, air quality, mountains and water resources with 342 marathon events held in China in 2018. Results: The results indicate that the spatial distribution of marathon events in China is negatively correlated with the elevation of the terrain (plain > hill > plateau > mountain > basin); climate (subtropical monsoon climate > temperate monsoon climate > temperate continental climate > tropical monsoon climate > plateau alpine climate), air quality (level 3 > level 2 > level 4 > level 1). Results indicate that buffer zones can protect water resources: there are 24 items in the buffer zone of river 0.5 km and lake 1 km, 131 items in the buffer zone of river 3 km and lake 5 km, 191 items in the buffer zone of river 5 km and lake 10 km, 298 items in the buffer zone of river 10 km and lake 20 km. Results indicate for mountain range buffer: 13 items in the 20 km buffer and 39 items in the 50 km buffer. Conclusions: Marathon events are more likely to be held on the third rung of China’s topography where a city has a typical landform (plains, basins, hills, or mountain) with good climate and air quality. Meanwhile a city with water and mountain resources for recreational events such as cross-country or obstacle course are essential. The contribution of this study is to systematically and intuitively reflect the influence of natural environment factors on the distribution of marathon events in China, and to provide evidence for the medium and long-term planning of marathon events in China, the selection of venues for different types of marathon events and how to attract participants.


2017 ◽  
Vol 145 (12) ◽  
pp. 5123-5140 ◽  
Author(s):  
Mengwen Wu ◽  
Chun-Chieh Wu ◽  
Tzu-Hsiung Yen ◽  
Yali Luo

This study investigates the statistical characteristics of extreme hourly precipitation over Taiwan during 2003–12 that exceeds the 5-, 10-, and 20-yr return values and 100 mm h−1. All the extreme precipitation records are classified into four types according to the synoptic situations under which they occur: tropical cyclones (TCs), fronts, weak-synoptic forcing, and vortex/shear line types. The TC type accounts for over three-quarters of the total records, while the front type and weak-synoptic forcing type are comparable (9%–13%). Extreme hourly precipitation is mostly caused by mei-yu fronts during May–mid-June and by TCs during July–October. The TC type tends to have a long duration time (>12 h) with a symmetrical evolution of hourly rainfall intensity, while the front type and weak-synoptic forcing type mainly occur over a short period (<6 h) with a slightly asymmetrical evolution pattern. The TC type is further divided into seven subtypes according to the location of the TC center relative to the island. When the TC center is over the island or near the coastline (distance <100 km), the spatial distribution of subtypes I–IV is largely determined by the interaction between the TC circulation and topography when a TC center is over the northwest, south, east, or northeast portion of Taiwan, respectively. When the TC center is far away (distance >100 km) from the island, the strength of the environmental southwesterly or northeasterly winds and the impingement of TC circulation on the east side of the Central Mountain Range are also key factors determining the spatial distribution of subtypes V–VII.


2020 ◽  
Author(s):  
Taylan Sançar

&lt;p&gt;The Eastern Turkish High Plateau (ETHP) presents one of the most critical areas of Turkish-Iranian Plateau, where active slip rates and kinematics of the faults have been used in models that aim to describe the overall deformation characteristics (such as; the beginning of the collision and convergence velocity) of the Arabian-Eurasian collision. However, lack of the spatial distribution of horizontal slip and rock uplift rates of the Bitlis-Za&amp;#287;ros Mountain Range (BZMR) prevent our understandings about active deformation of Turkish-Iranian Plateau. Mt. Mu&amp;#351;g&amp;#252;neyi that constitute the NW part of BZMR and southern margin of the ETHP is critically important because conflicting viewpoints related to the active tectonics of both the ETHP, Turkish-Iranian Plateau and Arabian-Eurasian collision zone currently being adopted in research into it. In this study, I extracted spatial distribution of the fault geometry in the Mt. Mu&amp;#351;g&amp;#252;neyi and river networks from DEM, satellite images and aerial photo in order to understand faulting mechanism and measure their cumulative offsets, respectively. Geomorphic indexes (mountain-front sinuosity, valley &amp;#64258;oor width to valley height ratio, transverse topographic symmetry factor, asymmetry factor, hypsometric curve and integral) and drainage pattern analysis (channel concavity, integral analyses and knick point analyses) have been used to isolate the tectonic activity of the region. The results of this study reveal that although dozens of dextral faults accommodate the strain in the region, the 260 km length dextral Kavakba&amp;#351;&amp;#305; Fault is the most important structure in the NW part of BZMR and it takes 60% of overall deformation. Previous studies suggest that 3&amp;#8211;4.5 Ma is needed to account for the measured 9 km cumulative offset in this region, however, I measured c.a. 24 km cumulative horizontal offset on Kavakba&amp;#351;&amp;#305; Fault that indicates c.a. 12 Ma needed to account for the offset. Morphometric studies point out sustaining significant uplift within the Mt. Mu&amp;#351;g&amp;#252;neyi and signify the uplift rate is larger than horizontal slip rate moreover my results contradict the idea that change in the nature of the collision zone 5 &amp;#177; 2 Ma ago. &amp;#160;Furthermore, I propose that NW part of BZMR is extremely important to understand when the modern configuration of the boundary faults of the Anatolian Scholle did form? Considering similarities between the Kavakba&amp;#351;&amp;#305; and the Naz&amp;#305;miye fault, which located at c.a. 70 km south of the North Anatolian Fault Zone in the Anatolian Scholle, in terms of their ages, orientations, slip senses and cumulative offset, I suggest that they belonged to the earlier dextral deformation zone along the southern margin of the collision that sinistrally offset by the East Anatolian Fault Zone (EAFZ) about 33&amp;#177;3 km. This offset estimate dived by calculated long-term slip rate of the EAFZ and Na-alkali basaltic activity in the Plio-Pleistocene that emplaced at the eastern part of the Anatolian Scholle yields that age of the EAFZ is 6 Ma. This study supported by T&amp;#220;B&amp;#304;TAK Project No:115Y684.&lt;/p&gt;


Author(s):  
Jongmin Byun ◽  
Kyungrock Paik

Along the eastern margin of the Korean Peninsula, a coastal mountain range spanning over 800 km with summits above 1500 m faces the East Sea (or Sea of Japan), the back-arc sea behind the Japanese Islands. Two contrasting hypotheses exist regarding the tectonic history of this coastal mountain range: long-lasting and progressive uplifts from the Early Tertiary to the Late Quaternary, and a short and intensive uplift during the Early Miocene. However, to date, no consensus has been reached. Here, we studied the spatial distribution of knickzones to understand the formation period and development pattern of this coastal mountain range. We extracted the knickzones in a drainage basin from digital elevation models, and investigated whether or not they are transient knickzones induced by the development of the coastal mountain range. We found that all identified knickzones were stationary, which was verified by slope-area and chi-elevation analyses. This implies that sufficient time has passed for all transient knickzones relevant to the growth of the mountain range to migrate up to the catchment boundary and disappear. We then calculated the time spent for the migration of transient knickzones from the outlet to their stream heads to be at least 5.1 to 10.6 Myr. Therefore, our results suggest that the current form of the coastal mountain range had been built at least before 5.1 Myr ago and has reached a quasi-equilibrium state up to the present, thus invalidating the prevailing hypothesis of the long-lasting and progressive development until the Late Quaternary.


2021 ◽  
Vol 9 (12) ◽  
pp. 178-191
Author(s):  
Basavarajaiah D.M ◽  
◽  
Narasimhamurthy B. ◽  
Ganesh Prasad T.S ◽  
Jaya Naik ◽  
...  

The Western Ghats, also known as Sahyadri is a mountain range that covers an area of 140,000 square km parallel to the Western coast of the Indian Peninsula .It traverses the states of Kerala , Tamilnadu , Karnataka ,Goa ,Maharashtra, and Gujarat. It is a UNESCO world heritage site and is one of the eight hottest hot spots of biological diversity in the world. It covers 5000 species of flowering plants ,139 mammals species ,508 birds species, and 179 amphibian species ,many discovered species live in the Western Ghats . At least 325 globally threatened species occur in this region. The region glitches many anthropogenic intervention like illegal mining, the establishment of human settlement and deforestation etc. From a Historical view, the Western Ghats is the home for tribes > 50 types of tribes are living in the Western Ghats from the anecdotal period. The majority of the tribal are largely dependent on forests for their livelihood. After the implementation of the forest policy , the tribal livelihood status really worsened in the Western Ghats , they are unable to meet the daily requirement of recommended food intake >2500 Kcl. After post-independence (73years ) of India many development programs are implemented in the tribal area for improvement of livelihood status , but as of calendar date they are facing many problems like economic instability , lack of literacy , lower level of quality of life and not politically empowered . In this context , in the interest of policy implication at the tribal area , the present study was undertaken to study the socioeconomic status and spatial distribution of tribal in the Western Ghats. This study practically helps the policymakers , planners of the policy, and researcher scholars to extrapolate the tribal settlement through the geo-spacing tag of tribal , socio-economic level, Knowledge and attitude of Conservation of Western Ghats at the population level .


Author(s):  
R.J. Barrnett

This subject, is like observing the panorama of a mountain range, magnificent towering peaks, but it doesn't take much duration of observation to recognize that they are still in the process of formation. The mountains consist of approaches, materials and methods and the rocky substance of information has accumulated to such a degree that I find myself concentrating on the foothills in the foreground in order to keep up with the advance; the edifices behind form a wonderous, substantive background. It's a short history for such an accumulation and much of it has been moved by the members of the societies that make up this International Federation. My panel of speakers are here to provide what we hope is an interesting scientific fare, based on the fact that there is a continuum of biological organization from biochemical molecules through macromolecular assemblies and cellular membranes to the cell itself. Indeed, this fact explains the whole range of towering peaks that have emerged progressively during the past 25 years.


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