Jökull - 01.12.2003, Blaðsíða 41

The 1783–1785 Laki-Grímsvötn eruptions
APPENDIX
The appendix contains English translations (by the senior author) of original text in the contemporary accounts containing
information on seismicity (Table A), explosive activity (Table B), lava flows (Table C), and sense of directions in the Fire
districts (Table D). The Index number links to citation numbers in the text. The first number in the Source column refers
to the numbered citations listed below and the latter indicates the page number in the original source for each quotation: 1.
Steingrímsson, 1783a; 2. Steingrímsson and Ólafsson, 1783; 3. Steingrímsson, 1783b; 4. Steingrímsson, 1788; 5. Eiríksson,
1783b; 6. Björnsson, 1783; 7. Thorarinsson, 1783; 8. Pálsson, 1783; 9. Hólm, 1784; 10. Stephensen, 1785; 11. Pálsson,
1794; 12. Stephensen, 1783; 13. Pétursson, 1783; 14. Thorsteinsson, 1783. Full reference to the original sources is given
in the bibliography in the back. Note that the term Vesturgjá is a synonym for Útnorðursgjá and similarily Austurgjá is a
synonym for Landnorðursgjá.
Table A: Seismic activity
Date Index Source Quotation
19 April–29
May
A1 5, p. 274 In mid-May I [Jón Eiríksson at Ljótarstaðir in Skaftártunga] felt some earthquakes, during nights especially. I kept this to
myself and did not hear any others speak of it until Ascension Day when some earthquakes were felt in the upper part of
Skaftártunga. From then on earthquakes increased (in frequency and intensity) so people slept in tents out on open fields.
Early June A2 13, p. 455 ...but the farm Ásar in Skaftártunga almost collapsed from the intensive earthquakes, which were associated with this
eruption.
1 June A3 2, p. 58 This day was the beginning of our afflictions, when strong earthquakes were felt, not only here in Síða, Landbrot, Meðal-
land and Álftaver, but also in Mýrdalur in the west and Öræfi in the east. These earthquakes increased in frequency and
intensity) the following week and were mostly felt in the mornings and the evenings.
9 June A4 4, p. 9 The night before strong earthquakes and tremors were felt.
9–11 June A5 5, p. 274 The earthquakes increased steadily during the first four days of the eruption. [until 11 June]
10 June A6 2, p. 58 ...earthquakes continued to be felt... [i.e., in the Síða district]
11 June A7 2, p. 59 All that day and the following night strong earthquakes were felt.
13 June A8 4, p. 9 ...cracking and thuds were heard behind the mountains in the northwest followed by earthquakes [i.e., associated with
activity at Útnorðursgjá]
14 June A9 2, p. 60 The lava emerged out from the Skaftá River gorge and along Árfjall mountain with such a murmur that the earth trembled
and vibrated along with continuous sparks of fire and claps of thunder, so few people rested or slept that night.
15 June A10 4, p. 11 All that day and the following night earthquakes were felt.
16 June A11 4, p. 12 The din [tremor?] and the cracking, the fires and the stench along with the earthquakes north of the mountains bordering
Síða was so frenzied, that no one was sure whether this settlement was safe.
18 June A12 4, p. 13 ...again the lava surged out of the western fissure, filling up the Skaftá River gorge which was both deep and wide, and
accompanied by intense earthquakes, tremors and frequent thunder claps. ...This day and night the thunderclaps were so
extensive that everything trembled and vibrated and earthquakes caused cracking noise from every house timber.
19 June A13 2, p. 62 Weather was calm, but earthquakes were frequent and hard.
23–26 June A14 2, p. 63 ...lava emerged from the Skaftá River gorge at steady rate accompanied by earthquakes and thunder and lightning were
observed all around.
30 June A15 4, p. 19 ...calm weather, thunderclaps and earthquakes along with a boiling noise from the fissure.
14 July A16 4, p. 21 ...for the fourth and last time a lava surge emerged out from Vesturgjá along with boiling, creaking and cracking noises and
such a din that everything appeared to be going out of control, [din = tremor?].
17 July A17 4, p. 22 What was left of the livestock crowded together out of their dismay or ran around shrieking in their own sound and some
dropped dead where they stood. [old Icelandic accounts show that when animals gathered in groups, it is indicative of
seismic activity]
18 July A18 4, p. 22 The din [tremor?] was so frenzied that I [Jón Steingrímsson] thought everything would be demolished.
20 July A19 4, p. 22 ...continuous earthquakes.
1–3 Aug. A20 4, p. 26 ...the same boiling was continuously heard from this gjá along with earthquakes, thunder, lightning and continuous out-
pouring of lava [gjá = Landnorðursgjá].
23–31 Aug. A21 4, p. 28 ...the eruption proceeded in similar fashion, except intensive earthquakes were felt and claps were heard from Austurgjá.
26 Sept. A22 4, p. 29 ...intensive tremors or rather earthquakes were felt again, especially in the eastern part of Síða and in Fljótshverfi, which
was followed by increasing activity and lava effusion to the north of the mountains...
24 Oct. A23 4, p. 30 This day earthquakes started again and strong stench was smelled from east-northeast...
Nov. A24 4, p. 31 ...occasional weak earthquakes were felt in Síða.
24 Nov. A25 4, p. 31 A strong earthquake was felt in Meðalland, but its intensity was much less here at the foot of the scarp.
Jan.–Feb.
1784
A26 4, p. 32 After a long period of freezing and heavy winds that lasted through January, strong earthquakes were felt again, though dif-
ferent than previous ones. Some moved the earth slightly up and down, others travelled like oceanic waves from northwest
to southeast. The frozen ground cracked with sound of thumps and claps.
14–25 Aug.
1784
A27 4, p. 35 In the summer 1784, 14 and 15 August weak earthquakes were felt here in Síða, which were related to activity at the
north-northeastern fissure, and the last one occurred on the 25 August. After that such activity [i.e., earthquakes] was not
perceived until it recurred in the Rangárvallasýsla and Árnessýsla were it ruined many farmhouses.
JÖKULL No. 53, 2003 39