French River: Ice Age Outburst
The sculpted bedrock landscape of the French River area of Georgian Bay, Ontario has attracted attention for many years. The suite of sculpted “s-forms” have been described individually in many locations and attributed to glacial erosion because they were closely associated with glaciated bedrock.
However, the beautifully preserved Georgian Bay sites showed that these forms are analogous to erosional forms created by flow separations in fast moving water and are elements making up an integrated landscape (P. S. G. Kor, J. Shaw, D. R. Sharpe, 1991. Erosion of bedrock by subglacial meltwater, Georgian Bay, Ontario: a regional view. Canadian Journal of Earth Sciences, 1991, 28(4): 623-642).The role of the glacier is now seen to be as a confining medium generating extremely high velocity pressurised floods rather than a primary agent of erosion. Geodoxa has captured UAV (drone) imagery of the French River Delta providing unprecedented perspectives on the suite of landforms. The role of secondary flows is illustrated by animated overlays of the vortices associated with a range of landforms. The posting demonstrates the potential of interpretive videos of geomorphic processes.
Cantley in Quebec: Ice Age Outburst
Towards the end of the ice age melt water from glaciers played a major role in shaping our land. During the last decades, glaciologists were able to recognize the traces of these subglacial water floods. This video will help to appreciate how vortex are carving the sculpted forms (s-forms) on the bedrock under the continental ice sheet.
THE OUTBURSTS OF THE ICE AGE
Just a teaser of a futur documentary; Towards the end of the ice age melt water from glaciers played a more important role than we believed. These waters have been the cause of many disasters at the regional level on several continents. During the last decades, glaciologists were able to recognize the traces of these floods. In the '80s, some Canadian earth scientists launched a new controversy that still persists today. According to their view the immense drumlins fields were formed by the gigantic outbursts of subglacial water. These disasters would have been almost continental in scope. For the antagonists our knowledge of glaciology does not hold such accumulation and emergence of waters from the base of the Laurentide Ice Sheet.
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THE PARADOX OF ANCIENT LANDSCAPES
This is the first of a series of documentaries on an important paradox of geology and geomorphology. After 10
years of research on the field and along with the many publications, we explain an intriguing aspect of the previous eras of our planet. Geologists and geomorphologists wonder why we don’t find too many real landscapes like the one we find today. Finding a relief is common in Paleozoic and Mesozoic time. But finding a landscape sculpted by differential erosion and weathering is no something too common. We travel around the world to film all these places and there is at least another 10 years to come to be able to cover the subject properly. We have many more earth scientists to meet on the field, the ones that know well the local geology. For now we don’t attempt to give an explanation. You will notice that the first part is accessible while the second part is more like a teaser as an invitation for earth scientists to step in. So we apologize for using technical terminology like “carbonate ramp” concepts that we will explain later.
Stromatolites of Salda Lake (Salda Gölü), Turkey
Filmed in February 2007, this short documentary presented a wonder of geology and biology: These living stromatolites grow in this highly alkaline Salda Lake. Turkey is famous for its amazing lakes which have very special chemistry from geothermal activities. The country rocks are ophiolites from the Yeşilova Ultramafic Complexe. These pieces of ancient ocean crusts were uplifted by tectonic forces and later altered by geothermal activities and surface water. Rocks like ophiolites are rich in magnesium plus combine by the other surrounding rocks like limestone and dolomites had produce a fresh water lake rich in MgCO3. Cyanobacterias and diatoms build their mounds, the so call stromatolites, by precipitating a hydromagnesite clay. Life is so incredible to store chemical energy. But in the mean time so fragile.
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LES DÉBÂCLES DE L’ÈRE GLACIÈRE
Vers la fin de l'époque glacière l'eau de fonte des glaciers a joué un rôle plus important que l'on ne croyait. Ces eaux auraient été la cause de plusieurs catastrophes à l'échelle régionale sur plusieurs continents. Depuis ces dernières décennies, les glaciologues reconnaissent l'existence de ces catastrophes. Dans les années 80, des géologues canadiens lancent une controverse qui persiste encore aujourd'hui, à savoir que les immenses champs de drumlins se sont formés par des débâcles des eaux sous glacières. Ces catastrophes seraient d'envergure presque continentales. Le seul obstacle d'une telle théorie est de démontrer comment de telles quantités d'eau auraient pu émerger de la base du glacier Laurentien.
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