Sedimentäre Ablagerungsräume

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Systeme Schelf / Schelfmeere Ozeane / Tiefsee Different delta types controlled by wave and tidal energy Fig. 3.31.

1 Sedimentäre Ablagerungsräume Alluviale Systeme Seen Wüsten Glaziale Systeme Deltas/ Ästuare Skinner & Porter 1989 Deltas und Ästuare Küsten karb.-evap. Systeme Schelf / Schelfmeere Ozeane / Tiefsee Different delta types controlled by wave and tidal energy Fig b Different types of large marine deltas controlled by waves and tidal currents (LE, ME, HE: low, medium, and high energy conditions, respectively) as well as sediment input (Hi, MI: high or medium input). Einsele 2000

2 fluvial-dominated bird-foot delta the example of the Mississippi Delta/ New Orleans Press & Siever 2001 Coarsening Upward Leeder 1999

3 Reading 1996 Leeder 1999

4 Reading 1996 Classification of modern deltas by Orton & Reading (1993) Beispiel: Nil-Delta Delta - Ebene Delta - Front Pro - Delta Einsele 2000

5 wave-dominated deltas tide-dominated deltas Einsele 2000

6 Einsele 2000 Ästuare - Trichterform - Brackwasser-Verhältnisse (je nach Zirkulationsmuster) - Sediment-Input fluviatil und marin - fluviatile Prozesse - marine Prozesse (Tiden- und Wellenenergie) -... Reading 1996

Typ A: well-stratified salt wedge estuaries river dominated, tidal and wave mixing processes are permanently

interface gradual salinity gradient from bed to surface water Leeder 1999 Typ C: well-mixed strong tidal

vertically mixed -type of Einsele, 2000) Typ D: theoretical endmember lateral and vertical homogeneity of

7 Typ A: well-stratified salt wedge estuaries river dominated, tidal and wave mixing processes are permanently or temporarily at a minimum Typ B: partially stratified tidal turbulence has destroyed upper salt wedge interface gradual salinity gradient from bed to surface water Leeder 1999 Typ C: well-mixed strong tidal currents completely destroy the salt wedge to fresh-water interface no more vertical salinity gradients ( vertically mixed -type of Einsele, 2000) Typ D: theoretical endmember lateral and vertical homogeneity of salinity Mischung Unterschiedliche Mischung Flusswasser Meerwasser aufgrund unterschiedllicher Zirkulationsmuster Einsele 2000

8 Reading 1996 a Reading 1996

9 10 km Beispiel: Deutsche Bucht Reading 1996 Rand- Meere Einsele 2000

10 Beispiel: Schwarzes Meer Einsele 2000

11 Küsten / Schelf Reading 1996 Schelfgebiete

12 Küsten Reading 1996 Jacobshagen et al Ausgleichsküsten Bahlburg & Breitkreuz 1998

13 Ausgleichsküsten Bahlburg & Breitkreuz 1998 Einsele 2000

14 Einsele 2000 Einsele 2000

15 storm-dominated shallow-marine environments Einsele 2000 Einsele 2000

16 HCS hummocky cross stratification ( Beulenschichtung ) Graham 1988 (in Tucker, Ed.) Reading 1996

17 Reading 1996 Reading 1996

18 Coast to offshore trends Leeder 1999 Gezeiten A Press & Siever 2001 Schwerpunkt B Springtide und Nipptide

19 Walker 1992 Siliciclastic tidal flats ( Wattenmeer ) Walker 1992

20 Einsele 2000 Postkarte (

21 tidal bundles Reading 1996 slack water = Stillwasser Reading 1996

22 Leeder 1999 b barrier islands Coe 2003 c

23 Einsele 2000 Coastal morphology vs. wave and tidal energy Leeder 1999

24 Ozean/Tiefsee Topographisches Profil des Ozeanbodens im Atlantik von Neu-England bis Gibraltar Press & Siever 2001 Tiefenbereiche Jacobshagen et al. 2000

CCD Carbonate shells dissolve in deep water below CCD (low T, high P), whereas

Silica shells may accumulate in purely siliceous oozes which are later transformed

2000 Einsele 2000 pycnocline: transitional layer between shallow upper water layer

25 CCD Carbonate shells dissolve in deep water below CCD (low T, high P), whereas silica shells and/or reddishbrown clay minerals are (relatively) concentrated. Silica shells may accumulate in purely siliceous oozes which are later transformed to cherts (diagenesis). + variations in time! Jacobshagen et al Einsele 2000 pycnocline: transitional layer between shallow upper water layer and deep water ; it may frequently also act as a thermocline and/or chemocline/halocline ( salinity) Einsele 2000

26 Bahlburg & Breitkreuz 1998 Strömungen / Wasserzirkulation Degens 1989

27 Material-/ Nährstoffzufuhr Leeder 19

28 Sediment distribution and deposition in deep sea environments Einsele 2000 Bahlburg & Breitkreuz 2012

Tenerife Gran Canaria Leeder 19 Submarine

29 Tenerife Gran Canaria Leeder 19 Submarine Canyons max. Tiefe (NN): ~3000 Relief im Canyon: >2500 Canyon-Breite am ~ 10 k vertical exaggeration ~8 Press & Siever 2001 Echo-sounding profile of the Congo submarine canyon off Zaire, African west coast

30 Leeder 19 Example: Amazon fan Leeder 1999

31 Leeder 1999 Einsele 2000

32 Einsele 2000 Leeder 1999

33 Trübeströme Allen 1997

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