Sedimentological characteristics of ice-wedge polygon terrain in Adventdalen (Svalbard). Environmental and climatic implications for the Late Holocene

Abstract

Abstract. Ice-wedges are widespread periglacial features in the landscape of Adventalen, Svalbard. The networks of ice-wedges have created areas with well-developed polygonal terrains in the lowest fluvial terraces in this valley. We have examined the sedimentological characteristics of the northern and southern banks of the Advent river for palaeoenvironmental purposes. The base of two sedimentary sections reported radiocarbon dates of 3.3 and 3.9 ka cal BP, respectively. The northern site is constituted by three very different lithostratigraphical units, which suggests that their formation should be related to different environmental and climate conditions. By contrast, the southern section shows a rather homogeneous composition, with no significant variations in grain size and organic matter content. In both cases the uppermost sediments are constituted by a thick aeolian deposit. According to our data, warmer climate conditions may have prevailed during the Mid Holocene until 3.3 ka cal BP with widespread peat formation in the valley bottom. Subsequently, a period with alternating soil formation and aeolian sedimentation took place from 3 to 2.5 ka cal BP, probably due to increasing climatic severity. During the last millennium a long-term cooling trend has favoured aeolian deposition in the lowest Adventalen valley.

Holocene permafrost history and cryostratigraphy in the High‐Arctic Adventdalen Valley, central Svalbard

“…4), which corresponds with the onset of ice-wedge formation in Adventdalen (Jeppesen 2001). Further to the east of site L2, up to 3.6 ka BP old peat within loess deposits is reported (Jeppesen 2001), Oliva et al (2014) even found up to 3.9 ka BP old peat in a loess exposure near site A2a. This indicates that the maximum age of loess accumulation increases upvalley.…”

“…[Colour figure can be viewed at www.boreas.dk] tal trends such as palaeo-wind, -snow and -moisture regime, as considered in e.g. Oliva et al (2014).…”

Late Quaternary sedimentation and permafrost development in a Svalbard fjord‐valley, Norwegian high Arctic

“…C) yielded an age of ca 2·9 ka as a minimum age for permafrost there (Jeppesen, ). Dating results from two other sites in that area have indicated that the aeolian deposits of FA VII began to accumulate between 3·3 ka and 3·9 ka (Oliva et al ., ). Cable et al .…”

“…The syngenetic assemblage of cryofacies CF2, CF6, CF8 and CF9 (Table ) formed in the deposits of FA VII, where the upward growth of permafrost followed the accumulation of aeolian sediment (Bryant, ; Oliva et al ., ). These cryofacies developed as segregated ice at the top of permafrost (Cheng, ; Mackay, ), as observed also in terraces at the flanks of Adventdalen and other valleys in central Spitsbergen (Vtyurin, ; Härtel, ).…”

Procesos Geomorfológicos Y Formas Del Relieve en Dos Cuencas Lacustres De La Península Byers (Isla Livingston, Antártida Marítima): Implicaciones Paleoambientales

“…A diferencia del Ártico donde son abundantes (ej. : FORTIER y ALLARD, 2004;Oliva et al, 2014), estas geoformas no están tan profusamente representadas en los enclaves libres de hielo de la Antártida RAFFI y STENNI, 2011;LÓPEZ-MARTÍNEZ et al, 2012). Los suelos ordenados adquieren mayor desarrollo en los ambientes húmedos de las playas levantadas altas que en las bajas.…”