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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Articles avec #excursions et voyages catégorie

Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

Back to Cap Blanc Nez, lets talk to the chalk layer of the Cenomanian, called the "blue chalk."

It 's in this layer of chalk that the tunnel under the Strait of Dover was drilled to a depth between 40 meters and over 100 meters below the seabed.
 

Geological profile of the land in which was dug the Channel Tunnel - according Image Channel Tunnel geological profile / Order Keane.

Geological profile of the land in which was dug the Channel Tunnel - according Image Channel Tunnel geological profile / Order Keane.

This strait called Strait of Dover or pas de Calais for our French friends, marks the boundary between the North Sea and the English Channel, and separates orunited, depending on your point of view, the continental Europe to Great -Britain.

The chalk cliffs that dresses the coast on both sides of the strait remind us that it is opened and closed several times during its history ... at a time when Britain was reachable on foot.

Above, Network of paleovalleys during the last glaciation, 25,000 to 20,000 years ago - down, the River Channel to the same period - Doc. The Channel River during the Last Glacial Maximum (20 -25à-ka), alleging Toucanne (2007), modified Elhers and Gibbard (2004)
Above, Network of paleovalleys during the last glaciation, 25,000 to 20,000 years ago - down, the River Channel to the same period - Doc. The Channel River during the Last Glacial Maximum (20 -25à-ka), alleging Toucanne (2007), modified Elhers and Gibbard (2004)

Above, Network of paleovalleys during the last glaciation, 25,000 to 20,000 years ago - down, the River Channel to the same period - Doc. The Channel River during the Last Glacial Maximum (20 -25à-ka), alleging Toucanne (2007), modified Elhers and Gibbard (2004)

The paleo-river Channel flowed there. Its history is complex and controlled by tectonics and the extension of the Pleistocene glaciers.

Previously, the Western Channel has functioned as a Pliocene gulf, with a mouthpiece / shoreline evolving according to changes in the level of the sea.

The establishment of vast ice sheets, several kilometers thick, in the middle Pliocene gave him his greatest importance ... in this maximum configuration, the Channel river harvested the waters of contemporary rivers : Orne, Seine, Somme, Thames, Rhine, Meuse , Weser Ems, Elbe and the meltwater from the British, Scandinavian and Alpine (via the Rhine) ice caps. The size of its watershed is then estimated at 1.2 million square kilometers.

Glacial Lake Elsterian 450,000 years ago - left, Doc. Gupta et al. - Right, doc. Cohen, Gibbard and Busschers, 2005. - a click for enlargeGlacial Lake Elsterian 450,000 years ago - left, Doc. Gupta et al. - Right, doc. Cohen, Gibbard and Busschers, 2005. - a click for enlarge

Glacial Lake Elsterian 450,000 years ago - left, Doc. Gupta et al. - Right, doc. Cohen, Gibbard and Busschers, 2005. - a click for enlarge

During the Pleistocene, a glacial dam prevented the flow of the Thames and the Rhine / Meuse in the North Sea, and formed a glacial lake northeast of the Weald-Artois anticline; south-west of it, a lower paleo-valley linked the current Great Britain to the continent.

Two gigantic outbursts will cut this connection. The first occurs about 425,000 years ago, and the water cascading in force, more than a million cubic meters per second, will dig and expand the Strait of Dover and flood the lowlands, leaving diamond shaped islands, found during explorations with sonar in the Channel today.

The second flood, more important than the first, occurs there are about 225,000 years; it will bisect the remaining thin peninsula.

A study of 2007conclue that the English Channel was created by erosion of the land bridge linking the Weald in the UK and the Boulonnais in France. More resistant portions of chalk left on both sides the white cliffs of Dover and the Cap Blanc Nez.

 

Location of the anticline Weald - Artois - Doc. Wikipedia

Location of the anticline Weald - Artois - Doc. Wikipedia

The chalk cliffs of Blanc Nez and of the White cliffs of Dover.- a clic to enlargeThe chalk cliffs of Blanc Nez and of the White cliffs of Dover.- a clic to enlarge

The chalk cliffs of Blanc Nez and of the White cliffs of Dover.- a clic to enlarge

Unless this is a phenomenon of rifting, a sudden collapse between two faults, which is the cause of the invasion of the paleo-valley by waters, the cliffs of Dover and Cap Blanc Nez marking the edges of the fracture.

The River Channel should again see the day when the next ice age ... in "another life"!

 

The permanent erosion of the cliffs on both sides of the Channel set back ever ... amending the foot of these, and also the route of the roads that dominate.

Two examples:
- The Blanc Nez, where a bunker broke, leaving concrete remnants on the beach,
- Or on the cliffs of Dover, where in 2011, an area the size of a football field has collapsed, leaving a very white scar and a chalk delta bordering the Channel.

This makes these places ...dangerous, but interesting for researchers of fossil ... that are renewed at the foot of debris by this destructive natural action.

 

Cap Blanc Nez - ripped blockhouse at the top of the cliff of Petit Blanc Nez and remains on the beach - photo Bernard Duyck 2015

Cap Blanc Nez - ripped blockhouse at the top of the cliff of Petit Blanc Nez and remains on the beach - photo Bernard Duyck 2015

Dover cliffs - the cliff-fall happened between Langdon Cliffs and South Foreland Lighthouse - photo John Mc Lellan / the Daily Mail 2012

Dover cliffs - the cliff-fall happened between Langdon Cliffs and South Foreland Lighthouse - photo John Mc Lellan / the Daily Mail 2012

Sources :

- Geologie info- Un aperçu de la géologie du Boulonnais – par André Holbecq - link

- Le GR du littoral, de Bray-Dunes à Berck – par Pierre Leflon – link

- Falaises de craie - link

- Falaises de craie - le Cap Blanc Nez - link

- Geology of Dorset: The Cretaceous rocks - link

- Daily Mail - The crumbling cliffs of Dover: Now France is even further away as thousands of tons of chalk crash into sea after frost and drought - link

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

Few kilometers and about 50 million years separate the Cap Blanc Nez and Cap Gris Nez; we pass from the Cretaceous at the Blanc Nez  to the Jurassic at Gris Nez.

The Plage de La Sirène / Mermaid Beach, near Cape Gris Nez, is a real "museum of plicative tectonics". One can discover a beautiful anticline, whose important flexure layers is related to Alpine folding. The dip of the layers is increasing as they approach the foreshore (to the north) to reach a subvertical position.

An anticline is a fold of a geological layer convex, dome-shaped; the latest layer is outside the fold.

We are in the presence of clay and limestone marl black from the Kimmeridgian, the "clays of Châtillon" and portlandiens sandstones, the "Grès de la Crèche", yellower (Tithonian)

 

Cap Gris Nez - the Mermaid Beach - photo © 2015 Bernard Duyck

Cap Gris Nez - the Mermaid Beach - photo © 2015 Bernard Duyck

 Cap Gris Nez on the Mermaid beach - tne anticline - photo © 2015 Bernard Duyck

Cap Gris Nez on the Mermaid beach - tne anticline - photo © 2015 Bernard Duyck

The anticline of Cap Gris Nez, the different layer - the green Star marks a break, highlighted on the right picture - a click to enlarge - photo © Bernard Duyck 2015The anticline of Cap Gris Nez, the different layer - the green Star marks a break, highlighted on the right picture - a click to enlarge - photo © Bernard Duyck 2015

The anticline of Cap Gris Nez, the different layer - the green Star marks a break, highlighted on the right picture - a click to enlarge - photo © Bernard Duyck 2015

Kimméridgien (-152 / -157 Ma) and Tithonian (-145 / -152 Ma) in the Upper Jurassic

Kimméridgien (-152 / -157 Ma) and Tithonian (-145 / -152 Ma) in the Upper Jurassic

The Banc of the killer whales / Banc des Epaulards mark the existence of an eroded anticline  cut flush to one of its sides.

Tectonics is complicated here: as stated André Holbecq, we find that there is not a single fold, but folds intersected by faults.

Cap Gris Nez / the Mermaid Beach: Banc of killer whales, an eroded anticline - photo Patrick De Wever

Cap Gris Nez / the Mermaid Beach: Banc of killer whales, an eroded anticline - photo Patrick De Wever

Cap Gris Nez / the Mermaid Beach: Banc of killer whales, from the level of the beach - Photo © 2015 Bernard Duyck

Cap Gris Nez / the Mermaid Beach: Banc of killer whales, from the level of the beach - Photo © 2015 Bernard Duyck

Cap Gris Nez / the Mermaid Beach: subvertical dip rocks - photo © 2015 Bernard Duyck

Cap Gris Nez / the Mermaid Beach: subvertical dip rocks - photo © 2015 Bernard Duyck

The cliffs of Gris Nez, and those of "Cran aux oeufs"  / Egg's cran, further south, represent the only example in Europe of cliff with a marl bedrock of Kimmeridgian, covered with sand and sandstone lenses. These egg-shaped blocks come from the landslide rubble of sandstone of the "Grès de la Crèche", which are barefoot in the sand formation.

 

Cap Gris Nez - "Egg" of sandstone, fell on the beach - Photo © 2015 Bernard Duyck

Cap Gris Nez - "Egg" of sandstone, fell on the beach - Photo © 2015 Bernard Duyck

 Cap Gris Nez - hummocky sandstones- photo © 2015 Bernard Duyck

Cap Gris Nez - hummocky sandstones- photo © 2015 Bernard Duyck

 Cap Gris Nez - hummocky sandstones- photo © 2015 Bernard Duyck

Cap Gris Nez - hummocky sandstones- photo © 2015 Bernard Duyck

Sources :

- Geologie info- Un aperçu de la géologie du Boulonnais – par André Holbecq - link

- Le GR du littoral, de Bray-Dunes à Berck – par Pierre Leflon – link

- Planet Terre ens-lyon - Un musée des mini-plis dans le Jurassique supérieur du cap Gris-Nez, Pas de Calais  / Pierre Thomas - link 

- Structure et évolution des falaises gréseuses et argileuses du cap Gris-Nez (Boulonnais, France) – Pierre Guillaume - link

- Parc Naturel  Régional des Caps et Marais d’Opale – Biodiversité en Caps et Marais d’Opale – link

- Etude morphologique des falaises du Cap Gris Nez – JF Vangilve  / Univ. De Lille Géographie physique - link

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

The  L.A.V.E. meeting of 13 and 14 June was intended, in addition to our reunion and film and slide shows, excursions in the area of ​​the Two Caps, Blanc Nez and Gris Nez, located in Boulonnais regio.

These excursions organized by Sylvie and Daniel Chereau and Pierre Leflon, have been documented and commented by André Holbecq our mineralogist.



From left to right, Grand Blanc Nez with the Obelisk of Dover Patrol, the Cran d'Escalles and Petit Blanc Nez - photo © 2015 Bernard Duyck

 

The start of the tour, with behind the parking, the trench of Cran d'Escalles and the cliff ofPetit Blanc Nez, in the background, the Cap Gris Nez, seen from the summit of Grand Blanc Nez - photo © 2015 Bernard Duyck

The start of the tour, with behind the parking, the trench of Cran d'Escalles and the cliff ofPetit Blanc Nez, in the background, the Cap Gris Nez, seen from the summit of Grand Blanc Nez - photo © 2015 Bernard Duyck

From left to right, Grand Blanc Nez with the Obelisk of Dover Patrol, the Cran d'Escalles and Petit Blanc Nez - photo © 2015 Bernard Duyck

From left to right, Grand Blanc Nez with the Obelisk of Dover Patrol, the Cran d'Escalles and Petit Blanc Nez - photo © 2015 Bernard Duyck

The start of the walk is the car park of Cran d'Escalles: it is a depression of the ground for access to the sea, bleeding into the white chalk of the cliff, called "Cran" in the Boulonnais, and " valleuse "in Normandy.

 The Cran d'Escalles in 1910 - Postcard Delcampe archives

The Cran d'Escalles in 1910 - Postcard Delcampe archives

 Geological map of northern France -  Cenomanian chalk and marl, in green bronze & Jurassic formations, in gray - Doc. BRGM

Geological map of northern France - Cenomanian chalk and marl, in green bronze & Jurassic formations, in gray - Doc. BRGM

 Petit Blanc Nez - Sample taking at the foot of the cliff - photo © 2015 Bernard Duyck

Petit Blanc Nez - Sample taking at the foot of the cliff - photo © 2015 Bernard Duyck

The Cenomanian in the geological time scale / in Cretaceous.

The Cenomanian in the geological time scale / in Cretaceous.

Chalks exposed on the cliff of the Petit Blanc Nez and the blocks pile up to his belonging to the Lower Cenomanian, subdivision of the Cretaceous.

This land is rich in fossils of marine animals that lived there about 100 million years ... sponges, arthropods, brachiopods, molluscs including various cephalopods (ammonites) and echinoderms. With luck it can find traces of the shark, ichthyosaur and pterodactyl.

 

 What may contain chalk? - Doc. Craies- crihan.fr

What may contain chalk? - Doc. Craies- crihan.fr

Petit Blanc Nez - fossils of spongy / Plocoscyphia - photo © 2015 Bernard Duyck

Petit Blanc Nez - fossils of spongy / Plocoscyphia - photo © 2015 Bernard Duyck

Petit Blanc Nez - imprint of mollusk - photo © 2015 Bernard Duyck

Petit Blanc Nez - imprint of mollusk - photo © 2015 Bernard Duyck

Petit Blanc Nez - fossille of spongy / Plocoscyphia meandrina / identification by André Holbecq - photo © 2015 Bernard Duyck

Petit Blanc Nez - fossille of spongy / Plocoscyphia meandrina / identification by André Holbecq - photo © 2015 Bernard Duyck

 Petit Blanc Nez - mollusk footprint and pyrite - photo © 2015 Bernard Duyck

Petit Blanc Nez - mollusk footprint and pyrite - photo © 2015 Bernard Duyck

The chalk also contains flint, very hard siliceous rock composed of chalcedony and opal of variable color who form kidneys.

In the roller benches, there are nodules of pyrite, an iron disulfide containing various impurities. Free, the pyrite samples are difficult to keep, and break down into iron oxide and sulfate (his name, pyrite, is attributed to Dioscorides making the first mention in the year 50, Pyros meaning fire in Greek ... because hit by a flint, it produces sparks capable of igniting tinder)

Petit Blanc Nez - left, flint sample - right, pyrite nodules - photo © 2015 Bernard Duyck

Petit Blanc Nez - left, flint sample - right, pyrite nodules - photo © 2015 Bernard Duyck

In the cracks, very hard water can deposit calcite crystals.

Petit Blanc Nez - calcite - photo © 2015 Bernard Duyck

Petit Blanc Nez - calcite - photo © 2015 Bernard Duyck

To follow : The Cap Gris Nez

 

Sources :

- Geologie info- Un aperçu de la géologie du Boulonnais – par André Holbecq - link

- Le GR du littoral, de Bray-Dunes à Berck – par Pierre Leflon – link

- Falaises de craie - link

- Falaises de craie - le Cap Blanc Nez - link

- De Belemniet - Cap Blanc-Nez aan de Kanaalkust in Frankrijk - link

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

The volcanic landscapes of Oregon and the Cascades range are characterized by specific structures including holes that drain the lakes.

One of them, aptly named Lost Lake, is located off Highway 20, close to the winter sports resort of Hoodoo, in the forest of Willamette. (NB: different lakes are in the United States the name of Lost Lake)

 

Lost Lake hole - Oregon - photo from Video Bend Bulletin

Lost Lake hole - Oregon - photo from Video Bend Bulletin

Every winter, the lake fills fed by meltwater and small rivers, before emptying slowly into a hole to dry, before giving way to a meadow. Everything is about balance between supply and drainage: it fills when intake exceeds drainage, and vice versa.

It is not known if the waters flowing into the hole are transported to an exit point, or if they seep into porous medium under the surface, to go recharging the great water table that feeds the springs located on each side of the Cascades .

This hole is there forever, according to the spokesman of the Willamette National Forest ... it's actually the skylight of a lava tunnel.

Near Hoodoo, various volcanic formations could be responsible for one of these lava flows channeled:

- Hodoo Butte, a cinder cone that covers the western edge of Hayrick Butte.

- Hayrick Butte is a tuya, or a subglacial volcano, adjacent to the first named. It is characterized by a flat summit plateau, triangular of 800 meter maximum length, and near vertical walls of 210 meters.

 

Hoodoo Butte, after a forest fire in September - photo Rvannatta

Hoodoo Butte, after a forest fire in September - photo Rvannatta

Hayrick Butte, a fine example of tuya / Oregon - photo Jsayre64

Hayrick Butte, a fine example of tuya / Oregon - photo Jsayre64

Several kilometers west of Lost lake, similar drainage holes exist at Fish Lake, at the junction of Highway 20 and Highway 126.

The Fish Lake also knows her seasonal cycles. It is located between two volcanoes: Mount McLoughlin north and Brown Mountain to the south.

Brown Mountain - Pacific Crest Trail - photo Michael McCullough / Flickr

Brown Mountain - Pacific Crest Trail - photo Michael McCullough / Flickr

 The Mount McLoughlin, from Willow Lake / Oregon - photo Little Mountain5

The Mount McLoughlin, from Willow Lake / Oregon - photo Little Mountain5

Brown Mountain is responsible of flows of basalto-andesitic lava, 2,000 years old, around the southern shore of Fish Lake.

The Mount McLoughlin is a cone with steep walls built on top of a shield volcano. The volcano appears there are less than 700 000 years. Three steps characterize its eruptive activity. The first is characterized by an explosive period that forms a volcanic cone whose remarkable heights approaching 900 meters. The presence of an ancestral shield inder the cone could explain this anomaly. During the second stage, around 200 000 years BP, of andesitic lava flows are emitted from the top of the cone and bury it. The third stage is characterized by viscous andesitic emissions from near the summit, as evidenced by the old eruptive vents of North and South Squaw Tip on the western side, and most fluid lava from the base of the volcano, mainly south . The most recent lava flows are dated between 25 and 30 thousand years; they are contemporary with the last glaciation.

 

Sources :

- Treehugger science - Oregon's Lost Lake is disappearing through a strange hole - link

- The Bulletin  - Lost Lake shrinking down a hole / Lava tube drains lake on Santiam Pass - link

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

Pass by Gullfoss and miss out Geysir, on our way back to the airport, would be unforgivable, even if the night falls ...

 

The Geysir geothermal field, in the Haukadalur valley, is a set with hot springs, geysers, a rhyolitic dome and a basaltic eroded volcanic cone, dated from the Pleistocene.
 

The Geysir geothermal field: geysers and hot springs

The Geysir geothermal field: geysers and hot springs

It houses the Icelandic geyser that gave its name to all others: the Icelandic verb gjósa indeed means "spring" ! The first historical mention of the site dates from 1294.


The Geysir geyser, on the eastern part of Laugarfjall dome, has experienced in historical times a turbulent history: in 1630, an earthquake causes his stop. Forty years later, its activity resumes ... so violently that it causes other earthquakes. It is reported that in 1845 the geyser reached a height of 170 meters.
Between 17 and 20 June 2000, an earthquake stimulates its activity, and Geysir reaches 122 meters in height, and its eruptions are eight times a day, before falling in 2003 to three per day and then become quite irregular .

 

The characteristic blue bubble of the Strokkur geyser - photo © 2015 Bernard Duyck

The characteristic blue bubble of the Strokkur geyser - photo © 2015 Bernard Duyck

Geyser Strokkur - gushing - photos © 2015 Bernard Duyck
Geyser Strokkur - gushing - photos © 2015 Bernard Duyck

Geyser Strokkur - gushing - photos © 2015 Bernard Duyck

The Strokkur geyser, neighbor, is still very active and steady, with an eruption every 5 to 10 minutes. Projections reach 15 to 20 meters.
It is mentioned since 1789, after an earthquake that created or released its duct. Its activity has fluctuated in the 19th century, before seeing his pipe clogged again in 1896. In 1963, the pipe was "cleaned" by the drill of Geysir Committee, and its eruption taken regularly, characterized by the formation of a big turquoise bubble that directly follows a crocus movement of the pool ; the pool, emptied by the eruption, then fills up quickly again.
For sequential view of the phenomenon in a better light, visit
Photovolcanica.
 

The two basins of Bleší - photo © 2015 Bernard Duyck

The two basins of Bleší - photo © 2015 Bernard Duyck

Blesi, the "flame", is formed by two communicating basins, a first hot and of blue color, the second, with cold water, is opalescent due to the silica in suspension, and less soluble in cold water ... everything is here question of temperature .
 

Bleší - details on the two basins - photos © 2015 Bernard Duyck
Bleší - details on the two basins - photos © 2015 Bernard Duyck

Bleší - details on the two basins - photos © 2015 Bernard Duyck

Fata, Konugshver, Little and Little Strokkur Geysir are active sources in the same sector.
 

The Geysir geothermal field - Fata, hot springs - photo © 2015 Bernard Duyck

The Geysir geothermal field - Fata, hot springs - photo © 2015 Bernard Duyck

The Geysir geothermal field - Konugshver - photo © 2015 Bernard Duyck

The Geysir geothermal field - Konugshver - photo © 2015 Bernard Duyck

A  last look at Geyser Strokkur, whose column appears unite with lower and lower cloud ceilings  - photo © 2015 Bernard Duyck

A last look at Geyser Strokkur, whose column appears unite with lower and lower cloud ceilings - photo © 2015 Bernard Duyck

These photos at twilight atmosphere shall close our Icelandic chronic.

 

Sources :

Global Volcanism Program -  Geysir

Photovolcanica – Strokkur geyser 

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

On the south coast of Iceland, under the Myrdalsjökull and between Vik and Skógafoss, one of Sandar home to a strange wreck in this setting.

The wreck of the Sólheimasandur - photo © Bernard Duyck 2015

The wreck of the Sólheimasandur - photo © Bernard Duyck 2015

On november 24, 1973, a Douglas Super DC-3, also known as Dakota, of the US Navy, had to make an emergency landing on the black sand beach of Sólheimasandur, in bad weather and short of fuel. The crew fortunately survived, but the aircraft was abandoned there. Over forty years of bad weather damaged the unit. Its wings and tail are reported missing, and his body riddled with holes is partially filled with black sand driven by the wind.
Local says that a local farmer discovered during a visit to the wreck that the pilots had switched to the empty tank ... while a second was full. This discovery allowed him to have quality fuel for his tractor and all his farm for a year.The tail of the DC-3 was sold to a couple running a hotel on the theme of this aircraft.

Photos of the DC-3 - photo © Bernard Duyck 2015
Photos of the DC-3 - photo © Bernard Duyck 2015

Photos of the DC-3 - photo © Bernard Duyck 2015

On the left, the DC-3 in its form of 1972 - photo Airteam

On the left, the DC-3 in its form of 1972 - photo Airteam

Other wings on the sandur : whooper swans. - Photo © 2015 Bernard Duyck

Other wings on the sandur : whooper swans. - Photo © 2015 Bernard Duyck

The way to go there :

Between Vik and Skógafoss, after the big rock of Péturseyjarvegur, count two small streams and turn toward the sea side through a passage lined with a cattle grid ... not recommended for single cars, the paved road, marked by small wood bollards, will lead you to the wreck located to 4 good  kilometers.

What you aerate and enjoy the texture of the Sandur !


In geological terms, a sandur (sandar plural) is a piedmont plain formed by glacial silt carried down and deposited by glacial meltwater. Usually broader than long, the sandar are common in Iceland, where geothermal activity under the ice thickness increases the action of meltwater on training of the sediment, when it is not the jökulhlaups (debacle of ice), the consequences of a subglacial eruption that mobilize large amounts of materials.

Péturseyjarvegur on the Sólheimasandur - photo © Bernard Duyck 2015

Péturseyjarvegur on the Sólheimasandur - photo © Bernard Duyck 2015

Skógafoss is an impressive waterfall, which sees cascading the waters of the Skoga river from a height of 62 meters; its width is about 25 meters.

According to the legend, the Viking Þrasi Þórólfsson placed a chest behind the waterfall. A child found the treasure several years later, but could only prevail a handful before the chest disappears. The handle is now preserved in the museum of Skógar.

Skógafoss, under the rainfall - photo © Bernard Duyck 2015

Skógafoss, under the rainfall - photo © Bernard Duyck 2015

Near the fall, many small Icelandic horses can be admired.
The Icelandic is a small saddle horse, probably a direct descendant of the horses brought by the Vikings during the colonization of Iceland. It has not been crossbred from the 900s, the importation of horses from that time still prohibited on the island.

Its natural selection gave it a high resistance to climate, a good sense of direction and a recognized frugality. In addition to its various dresses, it is characterized by its five gaits: in addition to the walk, trot and gallop, normal gaits of the horse, he practices amble and tölt, an four times broken amble, which allows him to always keep a foot on the ground, and allows the forehand to get up and be more free.

The Icelandic horse is content with a grass  yellowed  by the long snow cover - photo © 2015 Bernard Duyck

The Icelandic horse is content with a grass yellowed by the long snow cover - photo © 2015 Bernard Duyck

Icelandic horses - photos © 2015 Bernard Duyck
Icelandic horses - photos © 2015 Bernard Duyck

Icelandic horses - photos © 2015 Bernard Duyck

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

On the road to Jökulsarlon, we meet the Hvannadalshnjúkur - 2119 meters, the highest point of Iceland and of Öræfajökull glacier/volcano, located on the rim of the caldera of a volcano sheltered under the Vatnajökull ice cap, in Icelandic " the glacier of lakes. "

Vatnajökull, with an area of ​​8.300km², covers 8% of the area of ​​Iceland and hides four active volcanoes, the Öræfajökull south, the Kverkfjöll to the north, the Grímsvötn and the Bárðarbunga, northwest.

 

Öræfajökull, and its highest point, Hvannadalshnjúkur - photo © 2015 Bernard Duyck

Öræfajökull, and its highest point, Hvannadalshnjúkur - photo © 2015 Bernard Duyck

The Öræfajökull is a stratovolcano, with a basaltic to rhyolitic dominant, truncated by a summit caldera of 4 km x 5, occupied by the glacier of the same name (686 km² and volume 370km³) served by outlet glaciers, the Skaftafellsjokull and the Fjallsjökull.

Built mainly during the Pleistocene and the interglacial periods, his recent activity is dominated by a few summit explosions and flank effusions. From June to October 1362, an explosive eruption of VEI 5 ​​devastated the area, leaving it its name, which means "Wasteland, or abandoned land" ... it is the largest eruption since the settlement of Iceland. In 1727-28, an eruption of VEI 4 marked the caldera and the western flank.

 

Two outlet glaciers (outlet glaciers) of Öræfajökull : the Skaftafellsjokull and Fjallsjökull, to the left ofthe road - photo © 2015 Bernard Duyck

Two outlet glaciers (outlet glaciers) of Öræfajökull : the Skaftafellsjokull and Fjallsjökull, to the left ofthe road - photo © 2015 Bernard Duyck

Another outlet glacier of the Vatnajökull, the Breiðamerkurjökull ends with a glacial lagoon, known as Jökulsárlón, appeared around 1934 to 1935.

The ice tongue began to decline with the rising of temperatures, causing a calving process of  variable sized icebergs and increasing the size of the lagoon, which passed from 7.9 km² in 1975 to 18 km² today.



 

Breiðamerkurjökull declining between 1903 and 1980 - doc.Geodetic Danish Inst. & USAF

Breiðamerkurjökull declining between 1903 and 1980 - doc.Geodetic Danish Inst. & USAF

 Jökulsárlón - general view of the lagoon - photo © 2015 Bernard Duyck

Jökulsárlón - general view of the lagoon - photo © 2015 Bernard Duyck

Jökulsárlón - photo © 2015 Bernard Duyck

Jökulsárlón - photo © 2015 Bernard Duyck

Ice blocks are all different, very white, furrowed with black marks, or with a particular blue color ... for the oldest. An opening of the lagoon to the ocean lets the icebergs go out with the tides.
 

Jökulsárlón and his blue ice - photo © 2015 Bernard Duyck

Jökulsárlón and his blue ice - photo © 2015 Bernard Duyck

Jökulsárlón: the ice in all its forms - photo © Bernard Duyck 2015Jökulsárlón: the ice in all its forms - photo © Bernard Duyck 2015
Jökulsárlón: the ice in all its forms - photo © Bernard Duyck 2015

Jökulsárlón: the ice in all its forms - photo © Bernard Duyck 2015

Many seabirds, arctic terns, gulls, eider ducks, great skuas, gannets, puffins, nest nearby and are fishing in the lagoon.
 

Jökulsárlón - Couples of eider (Somateria mollissima) in formation - photo © 2015 Bernard Duyck

Jökulsárlón - Couples of eider (Somateria mollissima) in formation - photo © 2015 Bernard Duyck

The action of the tides and the accelerated retreat of the glacier suggest the birth of a deep fjord.

 

To Jökulsárlón, the name of the island is not usurped ... Iceland, the land of ice. - Photo © 2015 Bernard Duyck

To Jökulsárlón, the name of the island is not usurped ... Iceland, the land of ice. - Photo © 2015 Bernard Duyck

A last look to the Jökulsárlón lagoon - photo © 2015 Bernard Duyck

A last look to the Jökulsárlón lagoon - photo © 2015 Bernard Duyck

Jökulsárlón has been part of several films: two James Bond: "Dangerously yours" and "Die Another Day," a Batman, "Batman Begins" and served as Siberian decor in "Tomb Raider".

Photos of the film "Die another day" / 007.Photos of the film "Die another day" / 007.

Photos of the film "Die another day" / 007.

Sources :

- Global Volcanism Program - Oraefajökull

-    "                  "                  - Grimsvotn - Bardarbunga - Kverkfjoll

- Oreonstate Univ. - Oraefajökull

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages
 Fjaðrárgljúfur: a canyon in the palagonite. - Photo © 2015 Bernard Duyck

Fjaðrárgljúfur: a canyon in the palagonite. - Photo © 2015 Bernard Duyck

Two interesting sites in the Katla Geopark: Fjaðrárgljúfur and Kirkjugólf

Fjaðrárgljúfur canyon was formed 9,000 years ago at the end of the Ice Age. The withdrawal of an upstream glacier gave birth to a glacial lake, due to the presence of a rock bolt predominantly of palagonite dating from 2 Ma; its level rose until the water overcomes it and starts his erosion work... a winding canyon, along about 2 km, and deep in places of one hundred meters, was dug by the river Fjaðrá in rocks and palagonite (*).

(*): The palagonite is a mixture of minerals produced by the alteration, in interaction with water, of the glassy volcanic materials. Color, usually yellowish to brownish, can vary from green to gray. Clays and zeolites are the key components of palagonite.

 

Fjaðrárgljúfur Canyon - photo © 2015 Bernard Duyck

Fjaðrárgljúfur Canyon - photo © 2015 Bernard Duyck

Fjaðrárgljúfur canyon views from the level of the river Fjaðrá - photo © 2015 Bernard Duyck
Fjaðrárgljúfur canyon views from the level of the river Fjaðrá - photo © 2015 Bernard Duyck

Fjaðrárgljúfur canyon views from the level of the river Fjaðrá - photo © 2015 Bernard Duyck

The village of Kirkjubaejarklaustur, close to the previous site, is best known for the "Fire Sermon", Eldmessu, delivered on July 20, 1783 by the Pastor Jón Steingrímsson, supposed to have stopped the lava spills of the fissure eruption of Laki, and spared village. A modern church was built in 1974 in memory of the pastor.

On the left, the Rev. Jon Steingrimsson - photo of the film "Cloudkill 1783" - right, the new church of Kirkjubaejarklaustur, built in 1974 - photo klaustur.isOn the left, the Rev. Jon Steingrimsson - photo of the film "Cloudkill 1783" - right, the new church of Kirkjubaejarklaustur, built in 1974 - photo klaustur.is

On the left, the Rev. Jon Steingrimsson - photo of the film "Cloudkill 1783" - right, the new church of Kirkjubaejarklaustur, built in 1974 - photo klaustur.is

Near the village, in a marshy pasture, Kirkjugólf, a poygonal arrangement of 80 m², considered by the Vikings as "the paving of a church" is in facts the top of basaltic organs, eroded by glaciers and sea when they were on the south coast of Iceland, there are several thousands of years.
 

Kirkjugólf: the basalt columns in their environment - photo © 2015 Bernard Duyck

Kirkjugólf: the basalt columns in their environment - photo © 2015 Bernard Duyck

Kirkjugólf: part of unobstructed pavement discovered the verticality of the organ - photo © 2015 Bernard Duyck

Kirkjugólf: part of unobstructed pavement discovered the verticality of the organ - photo © 2015 Bernard Duyck

 Kirkjugólf: Retail - different kinds of polygons - photo © 2015 Bernard Duyck

Kirkjugólf: Retail - different kinds of polygons - photo © 2015 Bernard Duyck

To get there, you pass the Hildishaugur, "the hill of Hildir."

In the Landnáma, the book of Colonization, a medieval Icelandic manuscript, it is said that the Irish hermits lived in Kirkjubær before the Scandinavian settlement of Iceland. According to tradition, on the territory inhabited by Christians, pagans were considered unwelcome. Hildir Eynsteinsson of Meðalland, a pagan, tried to get through. When he stepped on the field, he fell dead and was buried in the hill that bears his name, a stack of rock blocks.

 

Hildishaugur and its explanatory panel - photo © 2015 Bernard Duyck
Hildishaugur and its explanatory panel - photo © 2015 Bernard Duyck

Hildishaugur and its explanatory panel - photo © 2015 Bernard Duyck

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

In the early morning, sunrise on the glacier Mýrdalsjökull lets hope a beautiful clear weather that will allow a good observation of the eclipse.

Our base is ideally located between the foot of the glacier and Vik, to the Grand Guesthouse Garðakot ... a place to stay that I recommend.

This small farm built in 1931 and enlarged in 1961, was inhabited by unmarried brothers Óskar and Guðjón Þorsteinsson. In 2012, it was completely renovated by the friendly owners, Eva and Vigfús, into a welcoming guest house.



The Grand Guesthouse Garðakot, our "base camp" - photo © 2015 Bernard Duyck

 Garðakot - sunrise over Mýrdalsjökull - photo © 2015 Bernard Duyck

Garðakot - sunrise over Mýrdalsjökull - photo © 2015 Bernard Duyck

The Grand Guesthouse Garðakot, our "base camp" - photo © 2015 Bernard Duyck
The Grand Guesthouse Garðakot, our "base camp" - photo © 2015 Bernard Duyck

The Grand Guesthouse Garðakot, our "base camp" - photo © 2015 Bernard Duyck

Mýrdalsjökull, the "Glacier of the Marsh's Valley", is the fourth largest glacier in the country; it measures 596 km². Its highest point is the icy dome Góðabunga, which overlooks the valley of Thórsmörk, mentioned in the eruption of April 2010. The ice caps of Mýrdalsjökull and its neighbor to the west, Eyjafjallajökull, are in effect separated by a band of one to two kilometers, the Fimmvörðuháls pass.

Mýrdalsjökull - photo Sat. Landsat OLi 09/20/2014

Mýrdalsjökull - photo Sat. Landsat OLi 09/20/2014

Mýrdalsjökull, its caldera, his outlet glaciers and its neighbor, Eyjafjallajökull - Doc. IES

Mýrdalsjökull, its caldera, his outlet glaciers and its neighbor, Eyjafjallajökull - Doc. IES

On calm appearance in the soft morning light, the glacier has several volcanic edifices, including the fearsome Katla volcano. The latter has a caldera of about 110 km², covered with a layer of ice of 400 meters thick. Its eruptions follow one another at a rate of one every 40-80 years. His last confirmed eruption date from 1918 .

Eruptions are generally confined to the caldera, subglacial and result in meltwater outbursts, the "jökulhlaups", creating a sandur, the Myrdalssandur. In the 2000s, many earthquakes were recorded in the caldera.

The eruption of Katla in 1918 - Photo archive The eruption of Katla in 1918 - Photo archive

The eruption of Katla in 1918 - Photo archive

The volcanic system of the Mýrdalsjökull is associated with the crack of Eldgjá, stretching over almost 70 kilometers. It erupted in AD 934, and has produced voluminous lava flows, about 18 cubic kilometers, ranging up to the edge of the ocean. This lava field, the Alftavershraun, that we cross on the way to the east, is covered by shave foams.

The Alftavershraun : the lava field of the crack of Eldgjá - photo © Jean-Michel Mestdagh

The Alftavershraun : the lava field of the crack of Eldgjá - photo © Jean-Michel Mestdagh

The Racomitrium lanuginosum,  foam on the lava field of Eldgjá - photo Snari Baldersson

The Racomitrium lanuginosum, foam on the lava field of Eldgjá - photo Snari Baldersson

The lava fields of Eldgjá (purple) and Laki (gray) - http card: //lartisan.eklablog

The lava fields of Eldgjá (purple) and Laki (gray) - http card: //lartisan.eklablog

In a 4°article, Vik and its surroundings.

 

Sources :

- Global Volcanism Program - Katla

- Grand Guesthouse Garðakot - link

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Publié le par Bernard Duyck
Publié dans : #Excursions et voyages

Parallel to that of Grindavik, the geothermal field Krísuvík-Seltun shows volcanic activity, characterized by cracks, a group of craters aligned NE-SW and small shield volcanoes, intersecting the Reykjanes peninsula western of the Kleifarvatn lake.
 

The geothermal field Krísuvík-Seltun - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - photo © 2015 Bernard Duyck

The volcanic system Krísuvík produced several eruptions since the settlement of Iceland. A major eruption of crater Ogmundargigar in 1151 was accompanied by a lava flow that reached the ocean.
The last listed by GVP took place in the 14th century: in 1325 and 1340.

Drilling for the purpose of exploitation the geothermal energy has been done there in the 1990s, the temperature under the surface is 200°C. An unexpected explosion in 1999 led to abandon the project, and left a crater 30 meters in diameter.

In 2009, the Krísuvík area has risen by 3 cm.
In February 2011, a seismic swarm of magnitude 
max 3.7, between 1.1 km and 4.7 km underground, is likely related to magma movements marked this area. It did not lead to an eruption.

The site remains potentially dangerous: due to the vapor explosion risk, it is advisable to stay on boardwalks.

 

The geothermal field Krísuvík-Seltun - fumaroles and altered rocks - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - fumaroles and altered rocks - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - altered rock - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - altered rock - photo © 2015 Bernard Duyck

 The geothermal field Krísuvík-Seltun - bubbling mud puddle - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - bubbling mud puddle - photo © 2015 Bernard Duyck

Seismicity continues to mark the Krísuvík area with a swarm of earthquakes, all magnitude less than 3, on March 31, 2015.
 

Seismic swarm on the Krísuvík 31.03.2015 (yellow circles) - doc.IMO
Seismic swarm on the Krísuvík 31.03.2015 (yellow circles) - doc.IMO

Seismic swarm on the Krísuvík 31.03.2015 (yellow circles) - doc.IMO

Krísuvík and sulfur:

Arriving there, one is immediately bathed in a "sweet smell" of hydrogen sulfide ... here succeeds mud pots, bubbling water, noisy fumaroles, hydrothermally altered rocks with amazing colors, and sulfur deposits.

The German scientist Robert Bunsen visited the site in 1845 and based his research on the Solfatara, proposed the hypothesis of the formation of sulfuric acid in nature.

Sulfur there was operated from 1722 to 1728 and again in the 19th century.

 

 The geothermal field Krísuvík-Seltun - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - tone agreements between weathered, oxidized rocks and the leaden sky - photo © 2015 Bernard Duyck

The geothermal field Krísuvík-Seltun - tone agreements between weathered, oxidized rocks and the leaden sky - photo © 2015 Bernard Duyck

Near the geothermal fields, two explosion craters, maar type are occupied by lakes.
The Grænavatn, 350 m wide with a depth of over 46 meters, of emerald color, changing following the brightness.
The Gestsstaðavatn is a bit smaller.

They both date back more than 6,000 years.

A peculiarity of craters Krísuvík is the small fraction of magmatic material expelled, the number of gabbroic enclaves, and the small extent of the row of craters, just 500 meters ... this suggests an eruptive phase during which a quantity of  semi solidified magma was apparently mobilized during a seismic event.
 

The Grænavatn, an explosion crater - Icelandroadguide picture.

The Grænavatn, an explosion crater - Icelandroadguide picture.

Sources :

- Global Volcanism program - Krisuvik

- Geothermal iceland – Graenavatn explosion craters - link

- Krýsuvík - Seltún geothermal area – wondermondo

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