Reconstructing cold climate paleoenvironments from micromorphological analysis of relict slope deposits (Serra da Estrela, Central Portugal)

Extensive slope deposits are described from Black Mountain, Canberra, with particular reference to a profile exposed in an excavation at 590 m on the lower eastern slopes of the mountain. Buried organomineral soil materials near the base of the slope deposits contain fragments of carbonized wood with an average age of 27,800 (+2500, - 1900) years B.P. This age is not significantly different from the mean age of 26,790 � 810 years B.P. for carbonized wood in slope deposits near Lake George, and is close to the mean age of 31,500 � 1000 years B.P. for slope deposits above 1000 m in the Snowy Mountains. A method for comparing the results of carbon-14 determinations is described. The Snowy Mountains deposits indicated a periglacial climate with mean annual temperatures at least 8-10�C lower than at present. On the basis of their similar appearance and age, it is suggested that the Black Mountain deposits were also formed under cold-climate conditions. If this were so, the synchronous slope deposits near Lake George (and river terraces and slope deposits in an upland tributary of the Shoalhaven River) must also have developed during a colder climate. The climatic and associated soil conditions considered necessary for the formation of periglacial deposits at Black Mountain are discussed. Estimates of the lowering in temperature (compared with present-day temperature) which would have been involved vary from a crude estimate of about 14�C (annual) with relatively high precipitations and prolonged snow cover, to a more conservative estimate of 9�C (winter), 11�C (summer), and 10�C (annual) if the winter precipitations and snow cover were light. Even under the latter conditions, tree cover would have been minimal or absent from the tableland environment.

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Late Pleistocence dynamics in central Pennsylvania (USA) – new findings on periglacial slope deposits, pedology and chronology

10.5194/egusphere-egu2020-5929 ◽

2020 ◽

Author(s):

Florian Hirsch ◽

Thomas Raab ◽

Patrick Drohan ◽

Alexander Bonhage

Keyword(s):

Late Quaternary ◽

Soil Formation ◽

General Term ◽

Plant Litter ◽

Cold Climate ◽

Central Pennsylvania ◽

New Findings ◽

The Us ◽

Slope Deposits ◽

Slope Direction

<p>Pleistocene dynamics are usually associated with the formation of characteristic landforms such as moraines, dunes, or kettle holes. However, cold climate processes can also shape the landscape but not result in such prominent relief features. This is especially true for slope deposits that have been formed in periglacial regions through geli-solifluction and/or cryoturbation. &#160;While the terms used to refer to such slope deposits may differ with the disciplines of soil science and/or geomorphology, such features are often still recognized by practicing scientists. In the US, geli-solifluction and/or cryoturbation features are subsumed with a very general term &#8216;colluvium&#8217; whereas in Europe a more sophisticated number of terms is used separating sediments which formed under cold climate processes from sediments which formed due to anthropogenic induced soil erosion. Our study focuses on the stratigraphy of late Quaternary deposits and the soil formation in the northern Appalachians. The study area wasn&#8217;t glaciated during the Wisconsin glaciation; hence no MIS 5 or younger glacial deposits are reported.</p><p>To advance a common terminology between geoscientist, we examined pedons representative of Holocene and periglacial dynamics that reflect the strong role that solifluction played in pre and MIS 5landscape dynamics. Especially on foot slopes and toe slopes pedon stratigraphy is characterized by a several meter-thick par-autochthonous deposits that are rich in clasts. Clasts in deposits are aligned with the slope direction and are imbricated; on back slopes par-autochthonous deposits are also present but more shallow. Stratigraphy and OSL chronology strongly suggests that during the late Pleistocene several phases of morphodynamics shaped the landscape via solifluction followed by an eolian input of silt to the soils/sediments. Geochemistry reflects the multi-layer character of the soil profiles showing clear differences between the bedrock and deposits above. Elevated values of manganese in the surface soil indicate the importance of plant litter biocylcing during the Holocene. Hence on a landscape scale, the distribution of soils and the pedogenesis is strongly related to the par-autochthonous character of the substrate rather than the bedrock.</p>

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Conceptualizing a mountain hydrogeologic system by using an integrated groundwater assessment (Serra da Estrela, Central Portugal): a review

Geosciences Journal ◽

10.1007/s12303-013-0019-x ◽

2013 ◽

Vol 17 (3) ◽

pp. 371-386 ◽

Cited By ~ 12

Author(s):

Jorge Espinha Marques ◽

José M. Marques ◽

Helder I. Chaminé ◽

Paula M. Carreira ◽

Paulo E. Fonseca ◽

...

Keyword(s):

Groundwater Assessment ◽

Central Portugal ◽

Serra Da Estrela

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Magmatic structures and kinematics emplacement of the Variscan granites from Central Portugal (Serra da Estrela and Castro Daire areas)

Journal of Structural Geology ◽

10.1016/j.jsg.2010.09.003 ◽

2010 ◽

Vol 32 (10) ◽

pp. 1450-1465 ◽

Cited By ~ 15

Author(s):

Helena Sant’Ovaia ◽

Philippe Olivier ◽

Narciso Ferreira ◽

Fernando Noronha ◽

Denis Leblanc

Keyword(s):

Central Portugal ◽

Variscan Granites ◽

Serra Da Estrela

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Recent research on the nature, origin and climatic relations of blocky and stratified slope deposits

Progress in Physical Geography Earth and Environment ◽

10.1191/0309133302pp352ra ◽

2002 ◽

Vol 26 (4) ◽

pp. 551-575 ◽

Cited By ~ 39

Author(s):

Henk van Steijn ◽

Jan Boelhouwers ◽

Stuart Harris ◽

Bernard Hétu

Keyword(s):

Extreme Events ◽

Debris Flows ◽

Cold Climate ◽

Climate Extreme ◽

Aeolian Transport ◽

New Developments ◽

Slope Deposits ◽

Mass Transfers ◽

Selection Of ◽

Process Material

A selection of subaerial slope processes is discussed together with the morphological and sedimentological traces that are left by the processes. Emphasis is on mass transfers related to (coarse) blocky slopes and to scree accumulations, either on steep or on gentle slopes. New developments in the interpretation of more or less clearly stratified slope deposits are discussed in the light of the findings of research focusing on present-day process-form (process-material) relationships. The question of the climatic (and, more specifically, the periglacial) significance of the different processes and their morpho-sedimentary expression is a returning theme in this paper. It is concluded that many deposits are formed by azonal processes, although their activity (in terms of magnitude-frequency combinations) is often relatively high under periglacial conditions. Some of the deposits point to (cold-climate) extreme events. This especially is the case for frost-coated clast flows, aeolian transport of large platy clasts, and to a lesser extent debris flows.

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The Natural and Cultural Heritage of the Serra de Estrela, Between UNESCO Geopark and Lithium Mining

Examining a New Paradigm of Heritage With Philosophy, Economy, and Education - Advances in Religious and Cultural Studies ◽

10.4018/978-1-7998-3636-0.ch015 ◽

2020 ◽

pp. 205-222

Author(s):

Giorgio Pirina ◽

Luca Onesti

Keyword(s):

Economic History ◽

Sustainable Tourism ◽

Mining Activities ◽

Mountain Area ◽

Natural Park ◽

Natural Parks ◽

History Of ◽

Central Portugal ◽

Development Plans ◽

Serra Da Estrela

With a review of the academic and journalistic literature, this chapter aims to further explore the shift toward a sustainable tourism in the context of UNESCO Natural Parks and Geoparks. Furthermore, the authors point out the persistence of a contradiction, that is, the presence of mining activities in the surrounding of above-mentioned UNESCO areas. After briefly reconstructing the socio-economic history of the mountain area of Serra da Estrela, located in the region of Beira Interior, in Central Portugal, the authors focus on the tension between two aspects: 1) the Post-Fordist model, concerning the transition to tourism development related to creation of UNESCO Natural Park and Geopark and 2) the reinforcement of lithium mining production and discovery of new deposits as an energetic and economic strategy for Portugal. In particular, the latter issue has given rise to various groups and movements of protest on a local basis. The claims of these groups suggest a radical paradigm shift in the development plans and in the conception of heritage in an ecological sense.

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