scholarly journals Glacifluviálně-glacilakustrinní sekvence u Vidnavy na severním okraji Žulovské pahorkatiny

2020 ◽  
Vol 27 (1-2) ◽  
Author(s):  
Martin Hanáček ◽  
Katarína Adameková
Keyword(s):  
Ice Sheet ◽  
Laminated Sediments ◽  
Large Lake ◽  
Mine Site ◽  
Lower Channel ◽  
Vertical Transition ◽  
Outwash Plain ◽  
Facies Associations ◽  
Kaolin Mine ◽  
Sandy Sediments

Glaciofluvial and glaciolacustrine sediments were discovered in a small sandpit situated 800 m SE from Vindava (the Polský kopec Site). Sediments fill two channels located in superposition. Three facies associations (FA) were distinguished in this sedimentary section. The base of the lower channel is formed by gravel lag overlain by gravel-sandy sediments of 3-D dunes and a side bar (FA1). The upper channel infill begins also by basal lag and grades to a fining-upwards sequence from sand to silt (FA2). The sequence is formed from the base up by sediments of small 3-D dunes, A-type ripples, B-type ripples, C-type ripples, and horizontally laminated sediments. The sequence reveals a vertical transition from glaciofluvial (sand) to glaciolacustrine (silt) sedimentation. The sedimentary section is terminated by flat glaciofluvial bedforms (FA3) deposited under upper plane bed conditions. These bedforms arose after the restoration of glaciofluvial conditions. The base of the glaciolacustrine sequence is located at an altitude of ~ 275 m as well as the Old Kaolin Mine Site (850 m SW from the Polský kopec Site) where very similar sediments have been already described. The sediments of both localities represent a proglacial outwash plain in front of the retreating ice sheet (FA1 consists of ~ 23% of erratic rocks), where a relatively large lake, or a system of smaller lakes evolved at the same time. 

scholarly journals Characteristics and origin of a Saalian glaciolacustrine to glaciofluvial succession in the Hümmling region, NW Germany

1997 ◽  
Vol 47 (1) ◽  
pp. 129-144
Author(s):  
Jacques Schwan ◽  
Cornells Kasse
Keyword(s):  
Ice Sheet ◽  
Gradual Change ◽  
Nw Germany ◽  
Northwest Germany ◽  
Outwash Plain

Abstract. In the lowlands of northwest Germany, glaciofluvial plateaus (German: Geestplatten), and pushmoraines built up by the Saalian ice sheet are surrounded by flat and low-lying country. In the study area in the Hümmling, the Geestplatte consists o f mainly sandy meltwater deposits with a capping of groundmoraine or till residue. This outwash plain was built up during the Main Drenthe Advance of the Saalian glaciation and subsequently overridden by the expanding ice sheet. The meltwater deposits form coarsening- upward sequences exposed in three sandpits in the study area. From base to top in the exposures, three waterlaid fades are distinguished: a basal glaciolacustrine fades, a transitional fades and an upper glaciofluvial fades. Unless erosion has interfered, the upward change from one fades to the next is markedly gradational. The paper gives arguments for the distal-lake origin of the basal fades. It supposedly formed as the fill of drainless depressions in the distant foreland of the ice-sheet margin. By this process, the terrain was levelled and prepared for a gradual change from glaciolacustrine to glaciofluvial depositional regime.

Some aspects of late Pleistocene-Holocene drainage of the River Thames in the eastern part of the London Basin

1975 ◽  
Vol 279 (1288) ◽  
pp. 269-277 ◽  
Keyword(s):  
Late Pleistocene ◽  
Ice Sheet ◽  
Drainage System ◽  
Early Holocene ◽  
Large Lake ◽  
Thames Estuary ◽  
River Thames ◽  
Relationship Of ◽  
The Relationship ◽  
Tectonic Pattern

Since 1967 the area of the Thames Estuary has been extensively surveyed using reflexion seismic techniques. The interpretation of these records coupled with the logs and samples from some 140 boreholes has led to the reconstruction of the Late Pleistocene/Early Holocene palaeodrainage pattern of the River Thames. The relationship of this drainage system to the tectonic pattern would indicate that there has been Late Pleistocene re-emphasis of the existing dominant structures. Also a large NW—SE trending monocline would appear to be still a positive area within this subsiding sector of SE England. Some evidence for the existence of a Late Pleistocene ice-sheet is presented. That this might well have dammed the existing drainage systems creating a large lake (Lake Tamesis) is a possibility that requires further investigation.

scholarly journals Ice-crevasse sedimentation in the eastern part of the Głubczyce Plateau (S Poland) during the final stage of the Drenthian Glaciation

2020 ◽  
Vol 12 (1) ◽  
pp. 726-736
Author(s):  
Tomasz Salamon
Keyword(s):  
Final Stage ◽  
Ice Sheet ◽  
Structural Features ◽  
Glacial Sediments ◽  
Marginal Part ◽  
Southern Side ◽  
Sedimentary Succession ◽  
Sandy Sediments ◽  
Glacial Tills ◽  
Later Phase

AbstractGlacial sediments in the eastern part of the Głubczyce Plateau, at the Krowiarki site, were studied. Two units were distinguished within the sedimentary succession. The lower unit is composed of mainly sandy sediments with diamicton interbeds, the upper unit of very fine silt and clay sediments that exhibit rhythmic lamination in parts. Based on the textural and structural features of deposits, local deformations and palaeoflow directions, it was found that the sediments had been deposited within an ice crevasse, which was initially open and functioned as an ablation flow artery. The sediments were deposited in the form of a small fan dominated by sheetflows. Glacial tills were also redeposited on its surface. In a later phase, the crevasse was blocked. As a result, it was filled with water, leading to the development of a crevasse lake in which low-energy deposition dominated. The crevasse style of deposition indicates that, in the final stage of glaciation, the marginal part of the ice sheet was in a stagnant phase. This conclusion applies to the part located on the southern side of the watershed of the eastern Głubczyce Plateau. The probable reason for the stagnation of the ice sheet was the distinct loss of ice supply above the local topography barrier due to the decreasing thickness of the ice sheet in the studied area.

scholarly journals GLACIFLUVIÁLNÍ VÝPLAVOVÁ PLOŠINA U KOLNOVIC A JEJÍ SROVNÁNÍ S TERMINOGLACIÁLNÍMI KUŽELY MEZI SOKOLSKÝM HŘBETEM A ZLATOHORSKOU VRCHOVINOU U JESENÍKU

2012 ◽  
Vol 19 (1-2) ◽  
Author(s):  
Martin Hanáček
Keyword(s):  
Short Distance ◽  
Ice Sheet ◽  
Point Of View ◽  
Outwash Plain ◽  
Marginal Lobe

Glaciofluvial sediments at Kolnovice originated on an outwash plain running along the ice sheet front. Its material is variable from petrographical and provenance point of view, as it was deposited from various parts of a wide ice sheet front. This contrasts with petrologically monotonous deposits of terminoglacial fans in this area (Písečná and Javorná sites), which originate from one marginal lobe of the ice sheet. In addition, the material in terminoglacial fans comes from the direct surroundings of the sites having been transported only a short distance.

ANALISIS KESTABILAN LERENG DINDING AKHIR DI PIT BARATLAUT PADA PENAMBANGAN BATUBARA DI PT. PUTERA BARA MITRA , KECAMATAN MENTEWE, KALIMANTAN SELATAN

KURVATEK ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 21-34
Author(s):  
Untung Wahyudi ◽  
Excelsior T P ◽  
Luthfi Wahyudi
Keyword(s):  
Slope Stability ◽  
Mining Operation ◽  
Subsurface Water ◽  
Mining System ◽  
Mine Site ◽  
Analysis And Design ◽  
The Stability ◽  
End Wall ◽  
Wall Slope ◽  
Mining Slope

PT. Putera Bara Mitra used open mining system for mining operation, Yet the completion of study on the end wall slope stability that  undertaken by geotechnical PT. Putera Bara Mitra in Northwest Pit and the occured a failure in the low wall on the 1st June 2012 led to the need for analysis and design the overall slope at the mine site. To analyze and design the overall slope, used value of the recommended minimum safety. The value was based on company for single slope SF ≥ 1.2 and SF ≥ 1.3 for overall slope. The calculation used Bichop method with the help of software slide v 5.0. Geometry improvements was done at the low slopes that originally single wall with a 30 m bench height and a slope 70° with SF = 0.781, into 4 levels with SF = 1.305. The analysis explained the factors that affect the stability of the low wall included the mining slope geometry, unfavorable drainase system, material stockpiles and seismicity factors. It was necessary to do prevention efforts to maintain the stability of the slope included the redesign to slope geometry, handling surface and subsurface water in a way to control slopes draining groundwater, vegetation stabilization using and monitoring slope using Total Station with Prism and Crackmeter to determine the movement of cracks visible on the surface. 

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