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Fig. 8 X-radiographs showing facies I-IV in basin L2, core A (cf. Fig. 7). Alternating organic-rich (dark) and minerogenic (light) layers show high contrast in laminated units B and D.

Figure 8 X-radiographs showing facies I-IV in basin L2, core A (cf. Fig. 7). Alternating organic-rich (dark) and minerogenic (light) layers show high contrast in laminated units B and D.

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Fig. 1. Map of north Troms showing the location of the three investigated subareas on Vanna and in Lyngen (cf. Fig. 2) and isobases for the Mair (Younger Dryas) shoreline (continuous and dashed lines; after Marthinussen 1960; Andersen 1968) and the Tapes transgression maximum shoreline (dotted lines; Meller 1967). Isobases for the Main shoreline refer to shore features formed near high-tide level (ca. 1.5 m a. mean s.1.) whereas those for the Tapes shoreline refer to the contemporaneous mean sea level (Moller 1989). The isobases should nevertheless be considered approximate (+1-—2m) at this scale; in Lyngen the plotted Tapes isobase is slightly too low (see text).
Fig. 1. Map of north Troms showing the location of the three investigated subareas on Vanna and in Lyngen (cf. Fig. 2) and isobases for the Mair (Younger Dryas) shoreline (continuous and dashed lines; after Marthinussen 1960; Andersen 1968) and the Tapes transgression maximum shoreline (dotted lines; Meller 1967). Isobases for the Main shoreline refer to shore features formed near high-tide level (ca. 1.5 m a. mean s.1.) whereas those for the Tapes shoreline refer to the contemporaneous mean sea level (Moller 1989). The isobases should nevertheless be considered approximate (+1-—2m) at this scale; in Lyngen the plotted Tapes isobase is slightly too low (see text).
Fig. 2. Maps showing topography, basin location, distinct raised shorelines and other features in the investigated areas: (A) Lenangsbotn—Jegervatn area, Lyn- gen, showing basins L2—LS5 which are situated on hummocky marginal moraine, and coring stations (crosses) in basin L1 (Lake Jegervatn); (B) Skipsfjorddal, Vanna, showing basins S1—S4 and radiocarbon-dated palaeosol site (x) in sand dune/blowout area (vertical shading); (C) Vannareid, Vanna, showing basin V1 (Lake Litlevatn). Bog shown by horizontal shading. Altitude in metres.
Fig. 2. Maps showing topography, basin location, distinct raised shorelines and other features in the investigated areas: (A) Lenangsbotn—Jegervatn area, Lyn- gen, showing basins L2—LS5 which are situated on hummocky marginal moraine, and coring stations (crosses) in basin L1 (Lake Jegervatn); (B) Skipsfjorddal, Vanna, showing basins S1—S4 and radiocarbon-dated palaeosol site (x) in sand dune/blowout area (vertical shading); (C) Vannareid, Vanna, showing basin V1 (Lake Litlevatn). Bog shown by horizontal shading. Altitude in metres.
Fig. 3. Views of the investigated areas at Lyngen and Vanna: (A) Lyngen alps viewed towards the southeast, showing ice-covered Lake Jegervatn (basin L1) and adjacent Late Weichselian local moraines; (B) basin LS at Lenangsbotn, Lyngen, showing morainic substrate with partial peat cover (foreground); (C) Skipsfjorddal showing the position of basin SI and palaeosol locality ‘x’ in raised beach/dune area. The Main (M) and Tapes (T) shorelines are indicated by arrows.
Fig. 3. Views of the investigated areas at Lyngen and Vanna: (A) Lyngen alps viewed towards the southeast, showing ice-covered Lake Jegervatn (basin L1) and adjacent Late Weichselian local moraines; (B) basin LS at Lenangsbotn, Lyngen, showing morainic substrate with partial peat cover (foreground); (C) Skipsfjorddal showing the position of basin SI and palaeosol locality ‘x’ in raised beach/dune area. The Main (M) and Tapes (T) shorelines are indicated by arrows.
Table 1, Radiocarbon dates from (a) raised basin sediment cores and (b) a palaeosol from Skipsfjorddal, and their relationship to former sea level. Sample depth (‘Unit/depth’) in basins is given relative to lake level. Lab. ref. suffixes ‘A’ and ‘B’ refer to dated NaOH-soluble and insoluble fractions, respectively. Calibrated ages are according to Stuiver & Reimer (1986). ‘Max’ and ‘Mean’ sea level refer to estimated spring high-tide level and mean sea-level, respectively.
Table 1, Radiocarbon dates from (a) raised basin sediment cores and (b) a palaeosol from Skipsfjorddal, and their relationship to former sea level. Sample depth (‘Unit/depth’) in basins is given relative to lake level. Lab. ref. suffixes ‘A’ and ‘B’ refer to dated NaOH-soluble and insoluble fractions, respectively. Calibrated ages are according to Stuiver & Reimer (1986). ‘Max’ and ‘Mean’ sea level refer to estimated spring high-tide level and mean sea-level, respectively.
Fig. 4. Summary diagram of the stratigraphy of lake basin cores showing sediment thickness, facies types, position of isolation and ingression contacts, radiocarbon datings and basin threshold elevations.
Fig. 4. Summary diagram of the stratigraphy of lake basin cores showing sediment thickness, facies types, position of isolation and ingression contacts, radiocarbon datings and basin threshold elevations.
Fig. 10. Litho- and diatom stratigraphy in adjacent cores (5 m apart) in basin L4, Lyngen. The suggested stratigraphic correlation, based on lithology and diato assemblages, indicates a major hiatus in core A and a slumped unit (C) in core B. The radiocarbon date provides a minimum age for basin isolation. This small, 40 x 60m diameter, 3.2m deep, morainic basin lies ca. 3m above the Tapes shoreline. Two 5.1 m long cores (A and B, Fig. 10), taken 5m apart, show considerable differences (aberrant I-III/I-IV-II facies se- quence), suggesting disturbance by slumping. The isola- Units A and B (marine facies I) — >0.75 m bioturbated, silty fine sand containing many pebbles, cobbles and shells, including Mya truncata in life position, capped by a thin, possibly uncomfortable, layer of plant detritus. The marine diatom flora can be divided into two assem- blage zones (1 and 2) dominated by marine species, with
Fig. 10. Litho- and diatom stratigraphy in adjacent cores (5 m apart) in basin L4, Lyngen. The suggested stratigraphic correlation, based on lithology and diato assemblages, indicates a major hiatus in core A and a slumped unit (C) in core B. The radiocarbon date provides a minimum age for basin isolation. This small, 40 x 60m diameter, 3.2m deep, morainic basin lies ca. 3m above the Tapes shoreline. Two 5.1 m long cores (A and B, Fig. 10), taken 5m apart, show considerable differences (aberrant I-III/I-IV-II facies se- quence), suggesting disturbance by slumping. The isola- Units A and B (marine facies I) — >0.75 m bioturbated, silty fine sand containing many pebbles, cobbles and shells, including Mya truncata in life position, capped by a thin, possibly uncomfortable, layer of plant detritus. The marine diatom flora can be divided into two assem- blage zones (1 and 2) dominated by marine species, with
Fig. 11. Lithostratigraphy and diatom summary diagram for basin L5, Lyngen, showing the position of the isolation contact. Legend in Fig. 12.
Fig. 11. Lithostratigraphy and diatom summary diagram for basin L5, Lyngen, showing the position of the isolation contact. Legend in Fig. 12.
Fig. 12. Diatom diagram for the upper part of the stratigraphy in basin LS (cf. Fig. 11).
Fig. 12. Diatom diagram for the upper part of the stratigraphy in basin LS (cf. Fig. 11).
Fig. 13. Litho- and diatom stratigraphy of basin S1, Skipsforddal, Vanna, showing the position of the isolation contact
Fig. 13. Litho- and diatom stratigraphy of basin S1, Skipsforddal, Vanna, showing the position of the isolation contact
Fig. 14. Lithostratigraphy and diatom summary diagram for basin V1 (Lake Litlevatn), Vannareid, Vanna. The favoured interpretation of the sequence places the isolation contact at the base of unit B and correlates units C and D with a Younger Dryas lacustrine phase. An alternative interpretation suggesting ingres- sion (shaded dashed triangle) and renewed isolation (open dashed triangle), seems less likely (see text). Diatom sampling interval and legend is given in Fig. 15. Unit B (transitional facies II) — 0.17 m finding-upward unit of mainly finely laminated silty gyttja/plant detritus
Fig. 14. Lithostratigraphy and diatom summary diagram for basin V1 (Lake Litlevatn), Vannareid, Vanna. The favoured interpretation of the sequence places the isolation contact at the base of unit B and correlates units C and D with a Younger Dryas lacustrine phase. An alternative interpretation suggesting ingres- sion (shaded dashed triangle) and renewed isolation (open dashed triangle), seems less likely (see text). Diatom sampling interval and legend is given in Fig. 15. Unit B (transitional facies II) — 0.17 m finding-upward unit of mainly finely laminated silty gyttja/plant detritus
Fig. 15. Diatom diagram for basin V1 (Lake Litlevatn), Vannareid, Vanna (cf. Fig. 14).
Fig. 15. Diatom diagram for basin V1 (Lake Litlevatn), Vannareid, Vanna (cf. Fig. 14).
Fig. 16. X-radiographs from basin V1, Vannareid, showing well-laminated sedi- ments (facies II and V) in the transition zone between marine (unit A) and lacustrine (unit E) sediments. Laminated unit D (right-hand radiograph) is particularly distinct. The apparent density difference between the two images is not directly comparable since different exposure times were used.
Fig. 16. X-radiographs from basin V1, Vannareid, showing well-laminated sedi- ments (facies II and V) in the transition zone between marine (unit A) and lacustrine (unit E) sediments. Laminated unit D (right-hand radiograph) is particularly distinct. The apparent density difference between the two images is not directly comparable since different exposure times were used.
Fig. 17. Shoreline-displacement curves for Lyngen (Lenangsbotn—Jagervatn) and Vanna (Vannareid—Skipsfjorddal), based on dated isolation contacts in lake basin sediment cores, and other data. The curve refers to high-tide level (threshold isolation level). Dashed and continuous parts of the curve indicate relative degree of uncertainty; dotted parts are interpolated or based on regional data. Question marks beside data points for basins V1 and LI denote gyttja dates that appear to be too old.
Fig. 17. Shoreline-displacement curves for Lyngen (Lenangsbotn—Jagervatn) and Vanna (Vannareid—Skipsfjorddal), based on dated isolation contacts in lake basin sediment cores, and other data. The curve refers to high-tide level (threshold isolation level). Dashed and continuous parts of the curve indicate relative degree of uncertainty; dotted parts are interpolated or based on regional data. Question marks beside data points for basins V1 and LI denote gyttja dates that appear to be too old.
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GeologyPaleontologyMarine transgression
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