Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
‘Bottom-up’ bedrock river response to rock uplift: Unravelling the controls of landscape responses to transience.
Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
Vise andre og tillknytning
2010 (engelsk)Inngår i: British Society for Geomorphology Programme & Abstracts. London, England, Aug 2010., 2010Konferansepaper, Publicerat paper (Annet vitenskapelig)
Abstract [en]

Bedrock rivers set the boundary conditions for landscape evolution. Most recent bedrock river research has been in steady-state settings in which rock uplift is matched by landscape lowering driven by bedrock river incision and slope lowering, but more attention is now being paid to bedrock rivers is transient settings (where transience in the fluvial system is triggered by changes in the rate of rock uplift and/or by climatic oscillations).  Transient responses in bedrock rivers close to base-level are dominated by ‘bottom-up’ processes.  Those processes remain less well understood than the ‘top-down’ processes that are thought to be characteristic of steady state landscapes and are driven by discharges of water and sediment. Key issues in understanding rates of landscape-wide response to transience are (i) rates of knickpoint retreat to transmit a base-level fall signal through the drainage net, and (ii) rates of hillslope response once that base-level fall has passed the foot of a hillslope.  Terrestrial cosmogenic nuclide (TCN) data from a transient landscape in southern Spain point to the latter being the rate-limiting control (“fast rivers, slow hillslopes”).  In terms of the former, morphometric and TCN data from coastal rivers in Scotland confirm knickpoint retreat in response to glacio-isostatic rebound, whereas TCN data from higher up these rivers, above the reach affected by glacio-isostatic base-level fall, point to more diffusive bedrock channel incision, without knickpoint retreat.  Determining why diffusive incision is initiated at a particular locality in those settings is difficult but in at least one case the incision is probably ‘pinned’ on resistant lithologies.  A wider and more taxing issue is the relationship between ‘bottom-up’ and ‘top-down’ incisional processes and whether the former must precede, and can evolve into, the latter.

 

sted, utgiver, år, opplag, sider
2010.
Emneord [en]
bedrock channel, knickpoint, sediment supply, Scotland, cosmogenic nuclides
HSV kategori
Forskningsprogram
geografi med naturgeografisk inriktning
Identifikatorer
URN: urn:nbn:se:su:diva-54238OAI: oai:DiVA.org:su-54238DiVA, id: diva2:392410
Konferanse
British Society for Geomorphology
Tilgjengelig fra: 2011-01-26 Laget: 2011-01-26 Sist oppdatert: 2018-01-12

Open Access i DiVA

Fulltekst mangler i DiVA

Søk i DiVA

Av forfatter/redaktør
Jansen, John
Av organisasjonen

Søk utenfor DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric

urn-nbn
Totalt: 163 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf