But magma surfacing along the rift zone is not alone in building this island. Under Iceland is a hot spot on the earth’s core, creating an abnormal upwelling of magma from mantle plumes onto the surface of the earth. Eruptions of this magma have created a vast system of volcanoes and fissures. The island first appeared above the ocean surface about 16 to 18 million years ago. By one source there are about 30 volcanic systems containing about 130 active and extinct volcanic mountains, most of them composite volcanoes which are usually part of a chain and spread in vast areas.
In addition to the volcanic mountains, the landscape is shaped by successive lava flows in various states of erosion and subsequent plant growth. One of the things that amazed me the most was this difference in textures, with lumpy lava flows from the last century abutting deep bodies of water (fjords carved by glacier retreat) abutting land suitable for livestock after millions of years of erosion. The once solid black basalt of volcanoes is now seen as black sand and pebbles on many of the beaches. I have tried to incorporate examples of lava flows and different states of erosion in my photos. My image of Landmannalauger (5th image), with a path leading to multicolored rhyolite mountains (rocks formed from lava with a greater concentration of silica) is one of my favorites. Lava flows mark the foreground, leading to a vast plain of sand from the continual weathering of the volcanic mountains in the background.
And then there are the glaciers. The glaciers and ice caps of Iceland cover 11.1% of the land area of the country but have a much greater impact on the shaping of its landscape. Many Icelandic ice caps and glaciers lie above volcanoes. When volcanic activity occurs under the glacier, the resulting meltwater can lead to a sudden glacial lake outburst flood, known in Icelandic as jökulhlaup. Vast areas, called outwash plains, are uninhabitable because of potential flooding. Jökulhlaups are also caused by accumulation of meltwater due to geothermal activity underneath the glacier. Roads and bridges in the paths of this meltwater are frequently destroyed. The visit into Thorsmork Valley towards Gigjokull was an experience requiring fording of streams and raging rivers of glacial snow melt, past glacial eratic boulders and over a glacial outwash plain. The day was overcast at first, then dark with rain that adds such mystery to the images included (2nd image, plus 10th, and some scattered below).
I hope you enjoy this gallery of volcanoes, glaciers, lava flows, fjords, icelandic horses, and waterfalls — even the northern lights made a showing.
