Caves and speleogenesis at Blomstrandsøya, Kongsfjord, W. Spitsbergen

Abstract

Blomstrandsøya, at Kongsfjord (78 57'N), Spitsbergen, is within the high arctic, a completely permafrozen zone. The bedrock consists of Paleozoic marbles and has yielded a surprising amount of karst features. Early phases of hydrothermal, possibly Caledonian, speleogenesis and subsequent Devonian karstification with redbed deposits is well documented. 62 active seacaves, and more than 30 relict karst caves were found in the coastal cliffs and in escarpment faces around the island. All caves have very limited extent; they are either quite short, like most of the active sea caves, or they are soon choked by frozen sediments and ground ice after a few meters. The deepest penetration was some 34 m into the surface cliff. Many of the relict caves are scalloped and display welldefined paragenetic wall and ceiling half-tubes, implying that they are indeed conduits, leading further into the rock mass, beyond their present permafrozen terminations. Most of the speleogenetic volume of the relict caves is ascribed to sub-glacial conditions during stadials, when the site was covered beneath thick ice sheets. In many cases, the present caves were formed by reactivation of pre-existing paleokarst voids. Due to the present intense gelifraction and erosion in the littoral zone, and the relatively constant sea level during the past 9.5 kyr, most of the volume of the sea caves can be explained by processes acting during the Holocene. Keywords SPELEOLOGY IN THE HIGH ARCTICAlthough there is a prolific literature on speleogenesis in alpine settings, relatively little is published on cave descriptions or speleogenetic studies in high arctic, permafrozen areas e

Chemical denudation rates and carbon dioxide drawdown in an ice‐free polar karst catchment: Londonelva, Svalbard

“…Palaeokarst caves were observed in section in the southwest cliffs of Blomstrandöya, and there are more than 60 sea caves along its 10 km shoreline (Lauritzen, 1998). Most of the relict caves in the coastal cliffs originated from subglacial processes (Lauritzen, 2006). In the south of Blomstrandöya marbles were extracted between 1910 and 1920 and the little mining town of London arose, giving the catchment its name.…”

Palygorskite in caves and karsts: a review

“…Rečnik (2013) described palygorskite as a few centimeters large cloth-like assemblies in fissures of silica-rich intraclastic dolosparite in the Idrija mercury mine (Slovenia). Lauritzen (2006) mentioned palygorskite from Western Spitsbergen in G18 Dobbeltgrotta (Paleozoic marbles) in small veins. Cílek (2012, pers.…”

The use of ground penetrating radar (GPR) in the investigation of historical quarry abandonment in Svalbard

“…Furthermore, deglaciation of Kongsfjorden is reported since the Late Weichselian (e.g. Lehman and Forman 1992, Lauritzen 2006, Ingólfsson and Landvik 2013) and is linked to sea level change and tectonic uplift, which still affect the region.…”

“…Since its discovery in 1906, Blomstrand has been shown to indeed consist mainly of medium- to high-grade metamorphic Caledonian marbles as well as pelitic schists and gneisses (for example Thiedig and Manby 1992; Lauritzen 2006). These authors describe the Caledonian rocks as striking north-south and having been subjected to two synmetamorphic, co-linear phases of isoclinal folding as well as refolding by post-metamorphic crenulation to kink-folds, which are often associated with west-directed thrust faulting and imbrication.…”