Jökull - 01.12.1986, Page 46

Fig. 4. Ketilsstadir: section at KE/
SUPPL. showing the tephra of the
— 1357 eruption filling a peat cutting.
- Mynd 4. Snið. KE/SUPPL. í mýri
við Ketilsstaði. Það sýnir forna mó-
gröf sem fylltist af gjósku í Kötlugosi
um 1357.
Fig. 5. The stratigraphy of section BRl at Ketilsstad-
ir (1979). — Mynd 5. Snið BR I í mýri við Ketilsstaði
(1979). Jarðvegur og gjóskulög.
(Katla —1357) also sealed a midden at Fell containing
an abundance of fish bones (Thórarinsson, 1972;
Einarsson, 1975,21; Einarsson etal., 1980,4).
TEPHROCHRONOLOGICAL RECORD
The Mýrdalur district lies at the margin of the
Eastern Volcanic Zone in southern Iceland. It has
repeatedly been affected by tephra fall from the sub-
glacial volcano Katla, below the icecap óf Mýrdals-
jökull some 20km to the north, and less frequently by
tephra from more distant sources. The tephra forms
distinct layers within the soil, which are well exposed
in drainage ditches such as those found at the Ketils-
stadir bog (fig. 4). The more or less continuous layers
can be easily followed within the bog and conveni-
ently used as stratigraphic markers; the age of several
tephra layers is known, providing dated isochrones.
Such dated horizons are, however, restricted to the
last 1100 years, although earlier layers occur at the
base of the exposed succession.
The tephra layers in the Ketilsstadir bog were
identified by comparison with other recently studied
soil sections in this area (Larsen, 1978; Einarsson et
al., 1980). The stratigraphy is shown in figure 5. Black

U*
vi

m
ATT
TEPHRA 5 mm
TEPHRA 5 mm
SAMPLED
IHEKLA 1597]
KATLA 15BCj
TEPHRA 4 mm
TEPHRA 3 mm
TEPHRA 10mm
CÖÁRSÉ ( PUMÍCES TÖ 5mm).
BLACK (N1) TEPHRA [KATLA
-1357] 140 mm
.....KE 1/1
..KE 1/2; 2/1; 3/1; 4/1
Kfj
•OLIVE GREY (5yr 3/2)..........
TEPHRA 10mm [HEKLA 1341]
TEPHRA 3mm
MODERATE ÐROWN (5yr 3-4/4)
FIBROUS PEAT WITH SOME TRACE
OF LENTICULAR BEDDING
260mm
GREYISH BLACK (N2) TEPHRA 42.5 mm
GRÉYISH BLACK (N2) TEPHRÁ ÍÖmm....
ÖLÍVÉ BRÖWN (5y 4|2) TEPHRÁ......
[LANDAM ASHl 25mm
BLÁCK TÉPHRÁ 15mm
BLACK TEPHRA 20-30rr
S i'
d±
V)
(’n
^ ■
53
¥7
i n
lilu
MODERATE BROWN (5yr 3|4)
FIBROUS PEAT* 300 mm
GREYISH BLACK (N 2) TEPHRA 40 rt
GREYISH BROWN (5yr 3|2)
FIBROUS PEAT 180 mm
DARK OLIVE GREY (5yr2/2) TEPHRA
70-80 mm
BLACK TEPHRA 60mm
TEPHRA 10mm
( Basa of ditch)..........._.KE 1115
.ke/suppl.
...KE/1 3; Br 1113; Br 1 /12
Br 1/13; KE1/6; 2/3; 3/3; 4|3
Br 1/14
.Br 1/15; KE 1/4
. KE 1/7
44