Reykjafjordur moraines

 

1975 field map of the Reykjafjordur moraines near the Kirkjubol hot springs.  I labelled the outer (northern) moraines O1 and the inner (southern) moraines O2 -- but things might be rather more complicated.......

In the valley of Reykjafjordur, on the eastern flank of Drangajokull in NW Iceland, there are two groups of recessional or readvance terminal moraines.  The older moraines (numbered in the O sequence) are Late Glacial or Neoglacial in age (several thousand years old) and the younger ones all date from the surges or readvances in the Little Ice Age -- within the past 300 years.

These satellite images are useful in seeing the relationships:

The satellite image showing the valley floor where the O1 and O2 moraines are in close proximity.  ......

Annotated image showing what appear to be two morainic loops in close proximity.  In 1975 we labelled these O1 (outer) and O2 (inner).  We also called them the first and second Kirkjubol stages.  The outer one might be the equivalent of the Jokulgardur moraine in Kaldalon, and the inner one might be the equivalent of the Kegsir moraine, which appears itself to be a double moraine in Kaldalon.  Further fieldwork and dating is required to sort out what has been going on here............

Having just discovered my field notes from 1975, here is some extra information.  The inner and outer moraines both apopear to consist of double ridges, with ice contact slopes on their up-valley faces.  So FOUR ice edge positions might actually be represented.  Between the O1 and O2 moraines there is a peaty depression with small lakes.  The outer moraine has a continuation as a lateral moraine of coarse boulders on the rock bench above.  The material from which the main complex of mounds and ridges is built is made of unsorted diamicton containing abundant rounded boulders and cobbles derived from overriden (and possibly bulldozed) outwash deposits from earlier phases of ice wastage.  On the northern edge of the O1 moraine there is a substantial channel which appears to have been used by a meltwater stream flowing along the ice front.  On the southern edge of the O2 moraine therev are tyerrace remnants of varved silts at least 3m thick -- demonstrating the existence of a substantial lake on the up-valley (proximal) flank of the moraine during ice wastage.

This satellite image shows the bend in the valley, with the prominent end moraine ridge projecting from the western valley side out towards the river.

The same image, annotated to show the M1 stage moraine (c 1850) and the associated dry outwash fan.