Accesso libero

Outcrops of Columnar Andesite Shaped by Periglacial Processes – Jersak Hills, King George Island, Antarctica

Piotr Migoń

Piotr Migoń

Institute of Geography and Regional Development, University of WrocławWrocław, Poland
Profilo Orcid
Cerca questo autore su
Sciendo|Google Scholar
Migoń, Piotr
 e 
Mateusz C. Strzelecki

Mateusz C. Strzelecki

  • Institute of Geography and Regional Development, University of WrocławWrocław, Poland
  • Alfred Jahn Cold Regions Research Centre, Institute of Geography and Regional Development, University of WrocławWrocław, Poland
Profilo Orcid
Cerca questo autore su
Sciendo|Google Scholar
Strzelecki, Mateusz C.
  
11 nov 2024
Outcrops of Columnar Andesite Shaped by Periglacial Processes – Jersak Hills, King George Island, Antarctica's Cover Image
INFORMAZIONI SU QUESTO ARTICOLO
Articolo precedente
Articolo Successivo
Cita
Scarica la copertina
Pubblicato online: 11 nov 2024
Pagine: 5 - 16
Ricevuto: 23 gen 2024
DOI: https://doi.org/10.14746/quageo-2024-0031
Parole chiave
© 2024 Piotr Migoń et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.

Fig. 1.

Geomorphological sketch of the Jersak Hills and the position of study area in King George Island (map courtesy of Kacper Jancewicz). Letter codes A to F indicate distinctive parts of the study area and are referred to in text. Yellow circles and numbers 1 to 9 indicate localities where rock strength tests using Schmidt hammer were performed
Geomorphological sketch of the Jersak Hills and the position of study area in King George Island (map courtesy of Kacper Jancewicz). Letter codes A to F indicate distinctive parts of the study area and are referred to in text. Yellow circles and numbers 1 to 9 indicate localities where rock strength tests using Schmidt hammer were performed

Fig. 2.

Panoramic views of the Jersak Hills. A – from north-west, with the Admiralty Bay in the background; B – from north-east, with the valley of Ornithologists Creek in the foreground. Letters A to D1 indicate different parts of the study area, labelled on Fig. 1.
Panoramic views of the Jersak Hills. A – from north-west, with the Admiralty Bay in the background; B – from north-east, with the valley of Ornithologists Creek in the foreground. Letters A to D1 indicate different parts of the study area, labelled on Fig. 1.

Fig. 3.

Different arrangements of columnar jointing in andesites of the Jersak Hills. A – narrowly-spaced vertical joints, with additional master joints spaced 1–3 m apart (cliffs are 12 m high); B – inclined columns dipping into the slope; C – inclined columns concordant with the slope (Schmidt hammer for scale); D – transition from vertical (right) to inclined columns (left); F – flat-lying columns exposed in a high cliff; F – vertical zones of hydrothermal alteration (marked by arrows).
Different arrangements of columnar jointing in andesites of the Jersak Hills. A – narrowly-spaced vertical joints, with additional master joints spaced 1–3 m apart (cliffs are 12 m high); B – inclined columns dipping into the slope; C – inclined columns concordant with the slope (Schmidt hammer for scale); D – transition from vertical (right) to inclined columns (left); F – flat-lying columns exposed in a high cliff; F – vertical zones of hydrothermal alteration (marked by arrows).

Fig. 4.

Unlike andesites, typified by distinct columnar jointing, basalts are subject to spheroidal weathering and rounded boulders are produced. A – rounded low bedrock outcrop; B – abundant rounded boulders around an outcrop.
Unlike andesites, typified by distinct columnar jointing, basalts are subject to spheroidal weathering and rounded boulders are produced. A – rounded low bedrock outcrop; B – abundant rounded boulders around an outcrop.

Fig. 5.

Intact strength of andesites of the Jersak Hills measured by Schmidt hammer. Statistics of readings at each site on the left, results of statistically significant differences between the sites using Kruskal-Wallis test on the right.
Intact strength of andesites of the Jersak Hills measured by Schmidt hammer. Statistics of readings at each site on the left, results of statistically significant differences between the sites using Kruskal-Wallis test on the right.

Fig. 6.

Scree and talus slopes in the Jersak Hills. A – high scree slopes under rock cliffs more than 20 m high, with fall as the dominant supply. Lobate toes of solifluction lobes are highlighted by the upper limit of a snow patch; B – less inclined scree supplied mainly by sliding debris from inclined outcrops; C – debris pile from a rock-slope collapse (outlined by dashed yellow line); D – debris mantle derived from in situ rock disintegration (Schmidt hammer for scale).
Scree and talus slopes in the Jersak Hills. A – high scree slopes under rock cliffs more than 20 m high, with fall as the dominant supply. Lobate toes of solifluction lobes are highlighted by the upper limit of a snow patch; B – less inclined scree supplied mainly by sliding debris from inclined outcrops; C – debris pile from a rock-slope collapse (outlined by dashed yellow line); D – debris mantle derived from in situ rock disintegration (Schmidt hammer for scale).

Fig. 7.

Solifluction mantles and effects of combined frost sorting, surface and subsurface wash. A – general view of the hillslope sediment transfer system, from bedrock outcrops to the valley floor; B – open-work texture of a stone stripe (in the middle of the photograph); C – convergence of stripes (highlighted by arrows) in a topographic low; D – deflection of stripes to the right, around a bedrock outcrop located in the lower slope.
Solifluction mantles and effects of combined frost sorting, surface and subsurface wash. A – general view of the hillslope sediment transfer system, from bedrock outcrops to the valley floor; B – open-work texture of a stone stripe (in the middle of the photograph); C – convergence of stripes (highlighted by arrows) in a topographic low; D – deflection of stripes to the right, around a bedrock outcrop located in the lower slope.

Fig. 8.

Hillslope sediment transfer system of the Jersak Hills
Hillslope sediment transfer system of the Jersak Hills
Lingua:
Inglese
Frequenza di pubblicazione:
4 volte all'anno
Argomenti della rivista:
Geoscienze, Geografia
Feed RSS della rivista