Glaciofluvial Formation Research Articles

Middle Pleistocene glaciation, alluvial fan development and sea-level changes in the Bay of Kotor, Montenegro

Abstract A coarse-grained alluvial fan at Lipci in the Bay of Kotor, western Montenegro, was deposited in the Middle Pleistocene by a high-energy, steep gradient proglacial stream draining an outlet glacier on the Orjen massif. The fan apex is currently about 50 m above sea-level, but the majority ( c. 60%) of this landform now lies offshore. Field mapping, sedimentological analysis and uranium-series dating were combined with a marine bathymetric survey and seismic profiling to explore the morphology and history of the entire fan complex. The Lipci fan was deposited on the margin of a large polje downstream of moraines that formed during the Middle Pleistocene (Marine Isotope Stage 12). The sea-level may have been more than 120 m lower than present during the glacial stages of the Middle Pleistocene. The sediments on the terrestrial portion of the fan are strongly cemented by secondary calcite and the oldest uranium-series ages show that the fan was deposited before 320 ka. These ages are consistent with a larger uranium-series dataset ( n =39) from other glacial and glacio-fluvial formations surrounding Mount Orjen. Seismic profiling of the submerged portion of the fan in the Bay of Kotor shows well-preserved palaeochannels with inset terraces. The Lipci fan is unusual because even its distal segments are well preserved after exposure to multiple post-Marine Isotope Stage 12 regression–transgression cycles. This is probably due to the strong cementation of the fan sediments and its sheltered location in the Bay of Kotor.

The glaciofluvial formation of Viinivaara as a water supply source for the city of Oulu in Northern Finland

The glaciofluvial formation of Viinivaara as a water supply source for the city of Oulu in Northern Finland

Groundwater resources at risk in the glaciofluvial formation of Jokkavaara in Rovaniemi area, Northern Finland

The best groundwater resources in Finland are generally situated in glaciofluvial formations with thick sand and gravel deposits. The glaciofluvial formation of Jokkavaara, in northern Finland near the town of Rovaniemi, is important for both its groundwater reserves and its sand and gravel resources. The groundwater and mineral resources of Jokkavaara was studied to define their quantity and quality, and to develop a land-use plan which would help civil servants of the municipality to make the decisions necessary for exploiting sand and gravel. The land-use plan shows the areas where exploiting mineral resources is not allowed or recommended because of the risks of contamination of groundwater, or because of injurious effects on the environment caused by noise and dust from gravel pits, or by spoilt landscape. The size of Jokkavaara is 5 km2, and its mineral resources are about 53 million cubic metres. The sand and gravel deposits are at the most, 50 m thick. Risks of contamination by fallout are small, due to the thick sand and gravel deposits above groundwater level. Exploiting mineral resources have no effect on groundwater quality either. By the land-use plan and legislation, good groundwater can also be protected in the future. Legislation limits the exploitation of mineral resources especially in groundwater areas.

Geosynthetic containment beneath Stockholm-Arlanda Airport

Arlanda International Airport in Stockholm, Sweden, is in the process of constructing a new, third runway. Through extensive siting studies and economic evaluation, the alignment of this runway and the associated taxiway has been located over an esker, a ridge-like glacio-fluvial formation common in Sweden. This esker is an aquifer and constitutes a water supply for the airport as well as a back-up water supply for more than 250,000 residents of the area. The use of approximately 100 tonnes (110 tons) of deicing products per runway each year, and the periodic use of solvents to remove rubber deposits from the pavement have resulted in the need for a protection system for this valuable water resource. As a result, design of a lining system was commissioned to minimize the impact of these constituents on the groundwater. Based on the preliminary design, select portions of the new runway and taxiway are to be lined with a geomembrane. Sensitive and critical areas will include the use of a geosynthetic clay liner (GCL) beneath the geomembrane to form a composite liner, and/or a geotextile above the geomembrane as a protective cushion. The geomembrane lined area totals approximately 330,000 m 2 (3,550,000 ft 2), making the project one of the largest installations of this nature in northern Europe.

The Importance of Glaciofluvial Features within Michigan's Port Huron Moraine

Abstract Evidence based on topographic quadrangles, aerial photographs, soils maps, and extensive fieldwork indicates that the Inner and Outer Port Huron moraines in the northwestern part of Michigan's Southern Peninsula represent a mega-assemblage of related glaciofluvial formations marking successive marginally stagnant glacial termini. Surficial sediments consist of ice-contact stratified drift and proglacial sand and gravel. Diamictons are very limited in extent and usually occur in the form of flow till. Uppermost sediments within the intervening Mancelona Plain show a transition from coarse, poorly sorted proximal deposits dominated by longitudinal bars to distal, fine-textured, well-sorted braided-stream deposits displaying sandy bedforms. Paleocurrent indicators show that meltwater streams first flowed directly away from the ice margin and then turned 90 degrees to the right (southwest) to flow parallel to the sandur's trend. Based on these data, we propose that what were previously mapped as the ...

The Importance of Glaciofluvial Features within Michigan's Port Huron Moraine

AbstractEvidence based on topographic quadrangles, aerial photographs, soils maps, and extensive fieldwork indicates that the Inner and Outer Port Huron moraines in the northwestern part of Michigan's Southern Peninsula represent a mega‐assemblage of related glaciofluvial formations marking successive marginally stagnant glacial termini. Surficial sediments consist of ice‐contact stratified drift and proglacial sand and gravel. Diamictons are very limited in extent and usually occur in the form of flow till. Uppermost sediments within the intervening Mancelona Plain show a transition from coarse, poorly sorted proximal deposits dominated by longitudinal bars to distal, fine‐textured, well‐sorted braided‐stream deposits displaying sandy bedforms. Paleocurrent indicators show that meltwater streams first flowed directly away from the ice margin and then turned 90 degrees to the right (southwest) to flow parallel to the sandur's trend. Based on these data, we propose that what were previously mapped as the Inner and Outer Port Huron moraines are actually the collapsed upstream portions of the Mancelona and Outer Port Huron outwash aprons, respectively. Although till is present in the subsurface, well‐log data and exposures reveal that waterlain deposits predominate in the upper 50 m of the stratigraphic column. The large volumes of superglacial fluvial drift and apparent absence of well‐integrated subglacial drainage features are consistent with a glacier exhibiting a frozen‐bed margin. Small disintegration ridges associated with major heads of outwash probably record the transition to warmer conditions with final deglaciation. Such relationships agree with recent interpretations of glacial dynamics in the northern Midwest and provide insights into glacial and sedimentological processes associated with a conspicuous and chronologically important moraine centrally located along the southern margin of the Laurentide Ice Sheet.

Former southwesterly ice flows in the Abitibi–Timiskaming region: implications for the configuration of the Late Wisconsinan ice sheet: Discussion

In a recent paper by Veilette published in the Canadian Journal of Earth Sciences, the large interlobate formation in the Abitibi-Timiskaming region was called a moraine; this confuses me and might mislead other readers, too. Now I have seen some parts of this formation, and I would like to make a comment on the use of the term in this context. After the 12th INQUA Congress in Ottawa, Canada, I had an opportunity to participate on the well-organized and interesting postcongress excursion C-10 (Ottawa-KuujjuarapikMontrkal) (INQUA Excursion Guide Book C-10, INQUA 1987). During that trip our excellent guides, Dr. Jean Veillette and Dr. Jean-Serge Vincent, showed us many details of the Hamcana Lake McConnell interlobate formation. They provided an interesting interpretation of the genesis of these huge gravel and sand concentrations, which are several kilometres wide, extend over a distance of some 800 km, and rise above the surrounding landscape (see Veillette). We fully agreed that we were able to find in this vast formation sections with glaciofluvial deltas, with esker characteristics, with kettle holes, and with glaciofluvial meltwater channels on some surfaces. In many cases we saw stratification typical of glaciofluvial deltas formed in glacially dammed lakes: for example, in the Lake McConnell moraine at Opimika Narrows and in the Hamcana interlobate moraine at Val-d'Or. They have exactly the same characteristics as, for example, the Vesivehmaa sandur delta of the Salpausselka icemarginal formation, southern Finland (see Fogelberg 1970; Atlas of Finland 1986, folio 122). In the Harricana interlobate formation a series of esker deltas was noted close to the position of the retreating ice front. Our guides could show us good evidence that the Hudson Bay and Labrador ice sheets during Late Wisconsinan time met in this interlobate zone and that these deposits were laid down by meltwaters collected in a zone of weakness between these two ice lobes that was characterized by crevasses and depressions. My question is, why call a totally glaciofluvial formation a moraine? (see Veillette). It causes confusion. We have no size limits for eskers. They can be small or very high and wide and flat, elongated formations deposited by glacial meltwaters in subor interglacial tunnels or in open crevasses facing towards the ice edge, or a group of consecutively occumng deltas deposited in open water (glacial lake or sea) at the ice margin. Eskers can be formed in an interlobate zone, as reported from Finland (Hheenkangas Pohjankangas and Pudasjarvi Taivalkoski esker complexes, etc.; see Punkari 1980; Atlas of Finland 1986, folio 122). We could call these interlobate formations esker complexes or just large interlobate eskers. The only reason Veillette called the Hamcana Lake McConnell formation an interlobate was that one of the referees wanted to change his term Hamcana Lake McConnell glaciofluvial interlobate complex to ( J . Veillette, personal communication, 1987). I hope there is not a new trend to rename glaciofluvial formations moraines. Moraines are distinctly different, glaciogenic landforms. When thinking of process and genesis of landforms, we have to clearly separate glaciogenic and glaciofluvial landforms.