Jökull - 01.12.1987, Page 62

in greater details. Bedding type, thickness, contacts,
sedimentary structures, texture, deformational fea-
tures, fossiis, and vertical and lateral facies relations,
were used to define and interpret the stratigraphic units.
Subfossil molluscs were sampled for dating purposes
and used as an aid in the environmental interpretations.
The textural analysis of the sediments was done in the
field, with a laboratory check of selected samples. The
grain-size scale used is the Udden-Wentworth graded
scale (Blatt, Middleton and Murray 1972, p. 46). The
term “gravel", if not specified, includes granules, peb-
bles and cobbles. For documentation and interpretation
of the sedimentological data a modified version of the
lithologic code of Miall (1977) and Eyles et al. (1983) was
used (Table I). I omit the interpretative parenthized last
letter of the Eyles et al. (1983) code, except when de-
scribing regionally extensive lag concentration deposits
(G(l)). Chronostratigraphical terminology used is in
accordance with Mangerud and Berglund (1978).
STRATIGRAPHY AND FACIES
RELATION SHIPS
A profile section of the Melabakkar-Ásbakkar cliffs is
shown as Fig. 2. The base of the profile is the high tidal
stand. The lower contact of the sequence where observ-
ed is striated bedrock, bearing witness to a glacial epi-
sode when the glaciers extended beyond the present
coast, prior to the glacial events registered in the strata.
The age of this oldest glacial episode is not known. All
Contacts:
Erosional
Sharp, contormable
Graded
Loaded
Composite Litho- vertical Stratigraphic facies section unit Facies/ Facies association Log
Sp, Ss.Gs, G(1). B(l> Melagil gravels and Yíi ftTM sands Emergence All
Ss Ss-FI Fl Fu . y. y 4 Melabakkar silts and . • ~J sands Sublittoral B C E
Glaciomarine
Gu.Gp.Ggn, Gs, Ss, St.Sp Dmu, Dcu, Sp.Ss.Su, Gu.Dms y/ FI-SI Dms Sp.St.Ss, Gu.Ggn Ásgil gravels lce-marginal outwash E
Á A A J Melar diamicton Lodgement till ACD
Y/y//(/1 Landhólmi sands lce-marginal delta D
~z= * ^4 Látrar beds Glaciomarine C F D
Esker fan
Gu.Ggn, Ggr, Gp.Ss.Su, S|, FI.Dmu, Dms Dms, Dmu, Gu.Gs, Ggn, Ss.SI ^V A Ás beds Morainal bank F G
■ • (1 Ásbakkar diamicton (5 A Glaciomarine A B C E G H
-111 1 1 1 II Striated bedrock m F S G
Fig. 3. Lithologiclogsfromthecliffs. ForlocationsandcorrelationsseeFig. 2. Lithologiccode inTable I. Inserted
figure: A composite vertical section (not to scale) showing lithofacies, stratigraphy and facies interpretations.
3. mynd. Jarðlagasnið frá bökkunum. Staðsetning sniða Í2. mynd. Setlykill í töflu I. Innskotsmynd: samsett snið.
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