Fjord in Namibia

Fjords are long, deep, and narrow glacially carved estuaries that were occupied by outlet glaciers. They play a dramatic role in ice-sheet stability (i.e., drainage and ablation), are sensitive to climate change during icehouse periods, and act as important sediment sinks (Syvitski et al., 1987; Bennett, 2003; Kessler et al., 2008; Briner et al., 2009; Moon et al., 2018)

(A) Digital elevation model of Kaokoland (northwestern Namibia) highlighting glacial valleys (white dashed lines). Circle labeled “B & C” represents geographic position of panels B and C. (B) U-shaped Gomatum valley. Note subvertical valley walls at background above modern alluvial fans, and Karoo Supergroup outliers. Valley is ∼2 km wide. (C) Topographic transect of U-shaped Gomatum valley, showing position of sedimentary and Etendeka Volcanics successions. (D) Longitudinal profile of Hoarusib valley and its interfluve (dashed line), and Karoo and Etendeka outliers. Note bedrock structures (Goscombe and Gray, 2008). v.e.—vertical exaggeration. Background topography is from SRTM3 (USGS 2006), Shuttle Radar Topographic Mission, 3 Arc Second scene SRTM_n47w053_n54w074, Filled Finished B 2.0, Global Land Cover Facility, University of Maryland, College Park, Maryland, February 2000) available at https://www2.jpl.nasa.gov/srtm/. Map was generated using GlobalMapper® GIS software.

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Net soos die water in ‘n magtige rivier wat hul walle oorstroom, bome ontwortel en selfs groot brue wegspoel, so is dit met ys en gletsers, wat alle mag gebruik en voortstroom met die geweldadigheid saamneem wat in hul pad is.  Namibië en die area wat getoon word is nie ‘n klein area nie.     Namibië en die woestyn was nog altyd bekorend vir baie mense – selfs die wild kon nie weggaan nie, al was dit droog en moes daar ver afstande gestap word vir bietjie water.

Daar is ‘n lewe in die woestyn vandag.

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Gaan na die mier ….

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Brandberg in Namibia

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Started in Swakopmund. Traveling along the coast past Terracebaai, Mowebaai, the Huarusibriver, Rockypoint, the Khumibriver, Cape Fria, Angra Fria up to the Kunene River mouth.

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Om te oorleef – lewe in die Namibwoestyn.

Namib: Surviving the Sand Sea is an independently produced natural history documentary about the adaptations of Namib Desert flora and fauna by Oliver Halsey

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Namibwoestyn – the Ocean of Sand (very old desert)

Photo:

The Kaokoland region of northwestern Namibia is characterized by a prominent bimodal topography where staircase-like plateaus (at ∼500 m, ∼1000 m, and ∼1500 m) separated by NNW-SSE–oriented escarpments are deeply dissected by a network of valleys in which modern rivers flow (Fig. 1A). These valleys are 1–5 km in width and 80–130 km in length and have steep, subvertical flanks defining U-shaped cross-profiles (Figs. 1B and Fig. 1C) whose depths range between 400 and 1200 m; interfluves occur up to 1.7 km above the thalweg of the Kunene Valley (Fig. 1A). These valleys are carved within hard Archean to Proterozoic lithologies of the Pan-African and Congo craton basement (Goscombe and Gray, 2008).

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The valley floors display abundant hard-bed glacial erosion features such as striae, scratches, grooves, and crescentic gouges (Fig. 2A) superimposed on whalebacks and roches moutonnées (see also Martin, 1953, 1981; Martin and Schalk, 1959). Scratches and striations are also developed on subvertical walls that flank the U-shaped valleys as well as on the subvertical westernmost (Purros; Fig. 1) escarpment, indicating westward and northward paleo-ice flows, respectively (Fig. 1A).

These valleys ubiquitously preserve remnants of partly eroded glaciogenic sediments of the Dwyka Group, forming the base of the Karoo Supergroup (Figs. 1B, 1C, and 2), whose age in the (restored) neighboring Paraná Basin of Brazil and Aranos and Karasburg Basins of Namibia is bracketed between ca. 299 Ma and ca. 296 Ma (Griffis et al., 2021). These glaciogenic sediments consist here of boulder beds (Fig. 2B) encompassing numerous exotic, faceted, and/or striated clasts and discontinuous ridges, patches, and lenses of poorly sorted conglomerates commonly affected by syn-sedimentary ductile deformation (Figs. 1D and Fig. 2C), interpreted as ice-contact morainal banks or ridges that experienced glaciotectonic folding (Dowdeswell et al., 2015). Importantly, glaciogenic sediments encompassing numerous and large (1–3 m) glacial erratics are plastered to the sides of these U-shaped valleys and along the escarpment, in association with scratched and striated valley walls (Figs. 2D and Fig. 2E). Glaciogenic deposits occur consistently at a height of 100 m above the valley bottom, which are interpreted as marginal moraines.

Fjords are glacially carved estuaries that profoundly influence ice-sheet stability by draining and ablating ice. Although abundant on modern high-latitude continental shelves, fjord-network morphologies have never been identified in Earth’s pre-Cenozoic glacial epochs, hindering our ability to constrain ancient ice-sheet dynamics.

It was showed that U-shaped valleys in northwestern Namibia cut during the late Paleozoic ice age (LPIA, ca. 300 Ma), Earth’s penultimate icehouse, represent intact fjord-network morphologies. This preserved glacial morphology and its sedimentary fill permit a reconstruction of paleo-ice thicknesses, glacial dynamics, and resulting glacio-isostatic adjustment. Glaciation in this region was initially characterized by an acme phase, which saw an extensive ice sheet (1.7 km thick) covering the region, followed by a waning phase characterized by 100-m-thick, topographically constrained outlet glaciers that shrank, leading to glacial demise. Our findings demonstrate that both a large ice sheet and highland glaciers existed over northwestern Namibia at different times during the LPIA. The fjords likely played a pivotal role in glacier dynamics and climate regulation, serving as hotspots for organic carbon sequestration. Aside from the present-day arid climate, northwestern Namibia exhibits a geomorphology virtually unchanged since the LPIA, permitting unique insight into this icehouse.

https://pubs.geoscienceworld.org/gsa/geology/article/49/12/1521/607263/Fjord-network-in-Namibia-A-snapshot-into-the

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4×4 Riverbed Driving in the Ugab River and Hiking the Olive Trail in the Namib Naukluft Park in late March 2017. Managed finding a way after the rain in the Ugab Riverbed with the beast from Savanna Car hire (V8 Landcruiser bushcamper) The magnificent Olive trail in the Namib Naukluft Park is 10km long and takes about 4-6 hours, depending on fitness and foto stops.

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Swakopmund day trip through the Moon valley to Goanikontes – Oasis.   The bed of the Swakop River

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The area around Sossusvlei is some of the most visually appealing places on earth.  The Dead vlei, or valley, is quite pretty, and it’s not hard to see why it is one of the most desirable destinations on earth. It was used in some movies, and is the most popular tourist destinations of Namibia.

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Tsauchab river coming down through the Sesriem Canyon on its way to Sossusvlei in the red sand dunes of the Namib Desert.

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Excellent video material Namibia

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2013

Taken in Kaokoland, Namibia where we were driving in desert, rocky, sand, water and extreme 4×4 conditions.

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Read also

Paleofjords of Namibia 

Duitsers van Namibië

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