Jökull - 01.12.1977, Page 65

TABLE 1 - TAFLA 1
Gravity connection Hannover—Reykjavík—Akureyri 1976.
Tenging þyngdarmœlistöðva Hannover—Reykjavik—Aknreyri 1976.
No. Instrum. Observer Station No. Date Time (UT) Readiirg Manufac. scale Tidal corr. Corrected mgal-value
1 79 Drewes Hannover 21629A 31.7. 5.02 4555.648 4723.165 —0.037 4723.128
2 79 Drewes Reykjavík 21941L 31.7. 17.47 5519.455 5723.621 —0.058 5723.563
3 79 Drewes Akureyri 60932 31.7. 20.46 5586.979 5793.701 —0.095 5793.606
4 85 Lehrke Hannover 21629A 31.7. 5.02 4661.090 4826.626 —0.037 4826.589
5 85 Lehrke Reykjavik 21941L 31.7. 17.28 5626.248 5827.665 —0.054 5827.611
6 85 Lehrke Akureyri 60932 31.7. 20.32 5693.856 5897.765 —0.093 5897.672
7 79 Drewes Akureyri 60932 18.8. 13.35 5586.964 5793.686 —0.042 5793.644
8 79 Drewes Reykjavík 21941L 18.8. 16.28 5519.478 5723.645 —0.065 5723.590
9 85 Lehrke Akureyri 60932 18.8. 13.22 5693.915 5897.826 —0.040 5897.786
10 85 Lehrke Reykjavik 21941L 18.8. 16.14 5626.332 5827.752 —0.062 5827.690
11 79 Drewes Reykjavík 21941L 21.8. 4.14 5519.522 5723.691 —0.067 5723.624
12 79 Drewes Keflavík 21941K 21.8. 6.39 5515.731 5719.756 —0.030 5719.726
13 79 Drewes Hannover 21629A 21.8. 17.22 4555.787 4723.310 —0.086 4723.224
14 85 Lehrke Reykjavík 21941L 21.8. 4.07 5626.390 5827.812 —0.067 5827.745
15 85 Lehrke Keflavik 21941K 21.8. 6.28 5622.559 5823.840 —0.033 5823.807
16 85 Lehrke Hannover 21629A 21.8. 17.22 4661.263 4826.805 —0.086 4826.719
for the gravity observations in the main
profile
LCR 79: Y7n = 1.00055 ± 0.00007
LCR 85: Y85 = 0.99988 ± 0.00010
LCR D 14: Y]4 = 1.00031 ± 0.00009.
Tidal reductions liave been calculated using
the Cartwright-Tayler development and region-
al tidal parameters lor the main waves. These
values were derived from the observations,
carried out 1975 in the temporary earth tide
station Laugaskóli, near the main profile (Torge
and Wenzel 1976). The amplitude factors 8 and
the phase lags k for the rnain rnoon tides 01
and M2 are:
JÖKULL 27. ÁR 63
8(01) =1.12 ±0.02, k(01) = 0°.7 ± 0°.8
8(M2) = 1.27 ± 0.01, k(M2) = 2°.2 ± 0°.6.
From separate adjustments for the single in-
struments, the weight differences between the
different gravity meters have been estimated
and introduced into the final adjustment:
mo(79): m0(85): m0(14) = 9 /ttgal: 11 Mgal:
24 /xgal,
resulting in P79: P85: P14 =1:1: 0.2.
The smaller weight for LCR D 14 might be
due to the anomalous drift caused by the fact,
that this instrument is ratlier new, while the
other gravity meters are more than 10 years old.