Jökull - 01.01.2017, Page 42

Holocene lavas in Bárðardalur, NE-Iceland
Figure 10. (a) Sr-Nd-isotopic variations of samples from the Bárðardalur region compared to volcanic prod-
ucts associated with Bárðarbunga and Askja. (b) Sr-Hf-isotopic variations of samples from the Bárðardalur
region compared to volcanic products associated with Bárðarbunga. (c) Nd-Hf-isotopic variations of samples
from the Bárðardalur region compared to volcanic products associated with Bárðarbunga. (d) 208Pb/204Pb
vs. 206Pb/204Pb isotopic variations of samples from the Bárðardalur region compared to volcanic products
associated with Bárðarbunga and Askja. – (a-d) Sr-Nd-Hf-Pb samsætu breytileiki hraunsýna úr Bárðardal í
samanburði við goseiningar tengdar Bárðarbungu og Öskju.
2008; Manning and Thirlwall, 2014). We noted ear-
lier that the major, minor and trace element chemistry
of Bárðarbunga basement rocks and the eruptive units
north of Vatnajökull defines a depleted endmember of
the Bárðarbunga volcanic system. Thus, the data pre-
sented in this study, along with previously published
data from the Veiðivötn region, provide a more exten-
sive view of the isotopic variability of the entire Bárð-
arbunga volcanic system. On the basis of the chem-
ical and isotopic data reported here, the Bárðarbunga
volcanic system, particularly its northern segment, is
regarded as being the most likely source for the lavas
of Bárðardalur valley.
Petrochemistry of the Northern Rift Zone: Future
prospects
In order to obtain better constraints on the total num-
ber of volcanic systems along the NRZ, their associ-
ation with each other and possible evolution of their
products with time, it is important to acquire data
from as many volcanic units as possible along the
JÖKULL No. 67, 2017 37