The First Results of Tephrochronological Study of Late Pleistocene–Holocene Volcanic Eruptions in the Zhom–Bolok River Valley (Eastern Sayan)

2019 ◽  
Vol 486 (1) ◽  
pp. 503-506 ◽  
Author(s):  
A. A. Shchetnikov ◽  
E. V. Bezrukova ◽  
E. V. Kerber ◽  
O. Yu. Belozerova ◽  
M. I. Kuzmin ◽  
...  
2003 ◽  
pp. 55-75 ◽  
Author(s):  
Ann Forsten ◽  
Vesna Dimitrijevic

A review of the fossil horses of the genus Equus from the central Balkans, a mountainous area comprising Serbia and Montenegro, is presented in this paper. The time period covered by the finds is from the late Early to and including the Late Pleistocene, but the record is not complete: the dated finds are Late Pleistocene in age, while Early and Middle Pleistocene are poorly represented. The horses found resemble those from neighbouring countries from the same time period, probably showing the importance of river valleys as migration routes. The Morava River valley runs in a roughly south-to-north direction, connecting, via the Danube and Tisa River valleys the Hungarian Pannonian Plain in the north with northern Greece in the south, via the Vardar River valley in Macedonia. In Pleistocene, large mammals, including horses, probably used this route for dispersal.


2021 ◽  
Author(s):  
James Christie ◽  
Georgina Bennett ◽  
Jacob Hirschberg ◽  
Jenni Barclay ◽  
Richard Herd

<p>Explosive volcanic eruptions are among the most significant natural disturbances to landscapes on Earth. The widespread and rapid influx of pyroclastic sediment, together with subsequent changes to topography and vegetation cover, drives markedly heightened runoff responses to rainfall and increased downstream water and sediment fluxes; principally by way of hazardous lahars. The nature and probability of lahar occurrence under given rainfall conditions evolves as the landscape responds and subsequently recovers following the disturbance. The relationship between varying sediment supply, rainfall patterns, vegetation cover and lahar activity is complex, and impedes forecasting efforts made in the interest of hazard and land use management. Thus, developing an improved understanding of how these systems evolve in response to volcanic eruptions is of high importance.</p><p>Here we present SedCas_Volcano[MOU1] , a conceptual sediment cascade model, designed to simulate the first-order trends, such as magnitude-frequency distributions or seasonal patterns, in lahar activity and sediment transport. We use the Belham River Valley, Montserrat, as a case study. This small (~15km<sup>2</sup>) catchment has been repeatedly disturbed by five phases of volcanic activity at the Soufrière Hills Volcano since 1995. The multi-phase nature of this eruption, together with the varying nature and magnitude of disturbances throughout the eruption, has driven a complex disturbance-recovery cycle, which is further compounded by inter-annual climatic variations (e.g. ENSO). Lahars have occurred frequently in response to rainfall in the Belham River Valley, and their occurrence has evolved through the repeated disturbance-recovery cycle. This activity has resulted in significant net valley floor aggradation and widening, consequent burial and destruction of buildings and infrastructure, as well as coastal aggradation of up to ~250m. Within SedCas_Volcano, we account for evolving sediment supply, vegetation cover and rainfall, to simulate the lahar activity and channel change observed in the Belham River Valley since January 2001. Following this, we test the model under different hypothetical eruptive scenarios. [MOU2] Our goal is to assess the efficacy of such models for reproducing patterns of lahar activity and geomorphic change in river systems that are repeatedly disturbed by volcanic activity.</p>


2015 ◽  
Vol 56 (9) ◽  
pp. 1256-1272 ◽  
Author(s):  
E.V. Deev ◽  
I.D. Zolnikov ◽  
E.Yu. Lobova

2015 ◽  
Vol 529 ◽  
pp. 499-510 ◽  
Author(s):  
Tao Liu ◽  
Chun Chang Huang ◽  
Jiangli Pang ◽  
Xiaochun Zha ◽  
Yali Zhou ◽  
...  

2020 ◽  
Author(s):  
Pascal Hedelt ◽  
MariLiza Koukouli ◽  
Isabelle Taylor ◽  
Dimitris Balis ◽  
Don Grainger ◽  
...  

<p>Precise knowledge of the location and height of the volcanic sulfur dioxide (SO<sub>2</sub>) plume is essential for accurate determination of SO<sub>2</sub> emitted by volcanic eruptions. So far, UV based SO<sub>2</sub> plume height retrieval algorithms are very time-consuming and therefore not suitable for near-real-time applications like aviation control. We have therefore developed the Full-Physics Inverse Learning Machine (FP_ILM) algorithm for extremely fast and accurate retrieval of volcanic SO<sub>2</sub> layer heights based on the UV satellite instruments Sentinel-5 Precursor/TROPOMI and MetOp/GOME-2.</p><p>In this presentation, we will present the FP-ILM algorithm and show results of the 2019 Raikoke eruption; a strong volcanic eruption which has emitted a huge ash cloud accompanied by more than 1300 DU of SO<sub>2</sub>, which could be detected  even two months after the end of eruptive event. We will also present first results of the recent Taal volcanic eruption on 13 January 2020 in Indonesia, which has injected a huge ash and SO<sub>2</sub> plume into the upper atmosphere, with plume heights of up to 20km. </p><p>The algorithm is developed in the framework of ESA's  "Sentinel-5p+ Innovation: SO<sub>2</sub> Layer Height project" (S5P+I: SO2 LH),  dedicated to the generation of an SO<sub>2</sub> LH product and its extensive verification with collocated ground- and space-born measurements.</p><p>The high-resolution UV spectrometer GOME-2 aboard the three EPS MetOp-A, -B, and –C satellites perform global daily atmospheric trace-gas measurements with a spatial resolution of  40x40km<sup>2</sup> at an overpass time of 8:30h local time. The UV spectrometer TROPOMI aboard the ESA Sentinel-5P satellite provides a much higher spatial resolution of currently 5.6x3.6km<sup>2</sup> per ground pixel, at an overpass time of 13:30h. In the future, also UV instruments aboard the Sentinel-4 (geostationary) and Sentinel-5 will complement the satellite-based global monitoring of atmospheric trace gases.</p>


2020 ◽  
Author(s):  
Ekaterina Matlakhova ◽  
Andrei Panin ◽  
Vadim Ukraintsev

<p>The Moksha River valley was studied in its lower part between the Tsna River confluence and the mouth of the Moksha River. Wide floodplain and two levels of terraces are presented on the studied part of the valley. The height of the floodplain is from 1 to 6 m, of the first terrace – about 9-11 m, of the second terrace – 18-22 m. The width of the valley in this area is about 14-16 km, but sometimes it can reach 20-22 km and more. The width of the floodplain is about 12-14 km.</p><p>The Moksha River is a meandering channel. Large and small (modern-size) meandering palaeochannels spread widely on the floodplain surface. These palaeochannels were the main objects of our study. Small palaeochannels have the same parameters as the modern river channel: their width is about 100-150 m, wavelength is between 300-400 and 600-700 m. For the large palaeochannels (macromeanders) the mean parameters are the following: width is about 250-300 m, wavelength is about 1500-2000 m. These large palaeochannels are the signs of high flood activity epoch(s).</p><p>In our study we used a number of field and laboratory methods. Twelve boreholes in large and small palaeochannels were made during fieldwork in August-September 2019. Organic material from studied palaeochennels was sampled to make radiocarbon (AMS) dating to find the time of palaeochannels’ formation and infilling. Also we made the reconstructions of paleo-discharges of the Moksha River based on paleochannels’ parameters.</p><p>We studied both large and small palaeochannels to reconstruct palaeohydrology and history of the Moksha River valley development in Late Pleistocene. Large palaeochannels correspond to the time of high river runoff. The oldest ones of small palaeochannels were studied to know the time of lowering of the river runoff. Presumably, large palaeochannels were formed at the end of Late Glacial (after LGM) when river runoff was much higher than the modern one. This period of extremely high runoff was previously distinguished in many river valleys of East European Plain, where formation of large paleochannels is usually associated with Late Glacial (the end of MIS 2). Lowering of runoff on the central part of the East European Plain is usually associated with the beginning of the Holocene.</p><p>This study is supported by Russian Science Foundation (Project № 19-17-00215).</p>


2004 ◽  
Vol 41 (7) ◽  
pp. 881-895 ◽  
Author(s):  
Brent C Ward ◽  
Bruce Thomson

Sediments in lower Chehalis valley span middle Wisconsin (Olympia nonglacial interval) to Holocene time. Sediments are divided into six units with chronological control provided by 14 new radiocarbon ages. Fluvial gravel spans the transition from the late Olympia nonglacial interval to the early Fraser Glaciation. Glaciolacustrine sedimentation represents the first definitive glacial activity in the valley and indicates that Vashon ice in the Fraser Lowland blocked the mouth of the Chehalis valley at ca. 18–17 ka BP. Ice then flowed down the Chehalis valley. The Chehalis valley deglaciated while ice persisted in the Fraser Lowland, forming another lake. After this lake drained, terraces and fans formed. This style of glaciation–deglaciation is typical of many watersheds peripheral to the Fraser Lowland in that local valley ice was slightly out of phase with ice in the lowland. This resulted in glacial lakes forming during both advance and retreat phases. However, in contrast to watersheds in the northwestern Fraser Lowland, no definitive evidence of a Coquitlam ice advance was found within the Chehalis valley. Although glaciers in the area were likely active and advancing, data from the Chehalis valley indicates that they were not as extensive as previously thought. Since ice source areas in the northeastern Fraser Lowland are in the leeward area of the Coast Mountains, it is suggested that lower precipitation resulted in limited glacier activity there during the Coquitlam Stade.


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