TY - JOUR

T1 - Organic debris and allochthonous coal in Quaternary landforms within a periglacial setting (Longyearbyen Mining District, Norway)

T2 - A multi-disciplinary study (coal geology-geomorphology-sedimentology)

AU - Dill, Harald G.

AU - Jolanta, Kus

AU - Andrei, Buzatu

AU - Sorin-Ionut, Balaban

AU - Stephan, Kaufhold

AU - Borrego, Angeles G.

N1 - Funding Information: Ground studies, including sampling a total of 20 study sites with big-pack samples, supported by satellite images (source of satellite images: Google Maps) and topographic data from the Norwegian Polar Institute (Norsk Polarinstitutt) formed the basis of the geological/sedimentological and geomorphological studies and provided the samples for the coal-petrographic and –petrophysical investigations (Table 1). The sedimentary composition of the samples was examined firstly under binocular and subsequently under the petrographic microscope for their mineral assemblage. These examinations were supplemented by XRD (= X-ray diffraction) the patterns of which were recorded using a PANalytical X'Pert PRO MPD Θ-Θ diffractometer (Co-Kα radiation generated at 40 kV and 40 mA) from 1° to 75° 2Θ with a step size of 0.03° 2Θ. The laser-based CAMSIZER technique is the method chosen for grain size and morphology measurements. Thermo analytical investigations were performed by a Netzsch 409 PC thermobalance equipped with a DSC/TG sample holder linked to a Balzers Thermostar quadrupole mass spectrometer (MS). About 100 mg of powdered material previously equilibrated at 53% r.H. is heated from 25 to 1000 °C with a heating rate of 10 K/min. Powdered samples were analyzed using a XRF (X-ray fluorescence) PANalytical Axios device and a PW2400 spectrometer. Samples were prepared by mixing with a flux material and melting into glass beads which were analyzed by wavelength dispersive X-ray fluorescence spectrometry (WD-XRF). To determine the loss on ignition (LOI) 1 g of sample material was heated to 1030 °C for 10 min.

PY - 2021/1/1

Y1 - 2021/1/1

N2 - High volatile bituminous coal C and B is currently exploited at Spitsbergen-Svalbard, Norway. Several coal seams formed during the Palaeocene, of which some were reworked by mass wasting (MW), (glacial)-fluvial (GF) and coastal-marine wave-dominated (WM) processes under periglacial conditions during the Quaternary. This supergene alteration resulted in different landforms and deposit bearing four different types of depositional environments in Svalbard: (1) Invisible floral and faunal remains, (2) visible floral remains, (3) drift wood, (4) coal placers s. The subaerial slow- and fast-moving MW was accompanied by chemical weathering giving rise to jarosite coatings indicative of acidic meteoric solutions, whereas the remaining subaquatic processes operated under neutral to slightly alkaline conditions. Fast-moving MW and WM are productive processes, whereas GF ones are destructive with regard to coal accumulation. The most efficient tools to study the origin of the OM-bearing coarse-grained deposits are the morphology and orientation of bioclasts while the LER/HER (= low exothermic / high exothermic reaction) ratio is used for finer-grained OM-bearing sediments. The maceral analysis revealed that the landforms accounted for by GF and WM were emplaced as a result of geogenic and anthropogenic processes and aged younger than 1900 CE, while MW is Quaternary and true geogenic. Driftwood is cast in the role of a marker for coal-bearing (fluvial-) marine environments different in age and rank of coalification. With this in mind it is an excellent tool to drawn the boundary in paralic settings between the marine and fluvial impact. In conclusion, coal fragments are markers for short-term, periodical and fast landform-building processes, whereas siliciclasts from the host and bedrock are markers for long-term and episodical geomorphological and sedimentological supergene alteration.

AB - High volatile bituminous coal C and B is currently exploited at Spitsbergen-Svalbard, Norway. Several coal seams formed during the Palaeocene, of which some were reworked by mass wasting (MW), (glacial)-fluvial (GF) and coastal-marine wave-dominated (WM) processes under periglacial conditions during the Quaternary. This supergene alteration resulted in different landforms and deposit bearing four different types of depositional environments in Svalbard: (1) Invisible floral and faunal remains, (2) visible floral remains, (3) drift wood, (4) coal placers s. The subaerial slow- and fast-moving MW was accompanied by chemical weathering giving rise to jarosite coatings indicative of acidic meteoric solutions, whereas the remaining subaquatic processes operated under neutral to slightly alkaline conditions. Fast-moving MW and WM are productive processes, whereas GF ones are destructive with regard to coal accumulation. The most efficient tools to study the origin of the OM-bearing coarse-grained deposits are the morphology and orientation of bioclasts while the LER/HER (= low exothermic / high exothermic reaction) ratio is used for finer-grained OM-bearing sediments. The maceral analysis revealed that the landforms accounted for by GF and WM were emplaced as a result of geogenic and anthropogenic processes and aged younger than 1900 CE, while MW is Quaternary and true geogenic. Driftwood is cast in the role of a marker for coal-bearing (fluvial-) marine environments different in age and rank of coalification. With this in mind it is an excellent tool to drawn the boundary in paralic settings between the marine and fluvial impact. In conclusion, coal fragments are markers for short-term, periodical and fast landform-building processes, whereas siliciclasts from the host and bedrock are markers for long-term and episodical geomorphological and sedimentological supergene alteration.

KW - Coastal zone

KW - High volatile bituminous coal C/B

KW - Periglacial

KW - Quaternary reworking

KW - Spitsbergen-Svalbard

UR - http://www.scopus.com/inward/record.url?scp=85099500082&partnerID=8YFLogxK

U2 - 10.1016/j.coal.2020.103625

DO - 10.1016/j.coal.2020.103625

M3 - Article

AN - SCOPUS:85099500082

VL - 233

JO - International Journal of Coal Geology

JF - International Journal of Coal Geology

SN - 0166-5162

M1 - 103625

ER -