Tektonik und Vulkanismus

Transkript

1 Tektonik und Vulkanismus Endogene Dynamik der Planeten Ernst Hauber Institut für Planetenforschung Ringvorlesung HGF Allianz «Planetenentwicklung und Leben» , TU Berlin

2 Überblick Tektonische Regimes Krustenbildung Tektonische Elemente (Störungen) Gräben, Rifts, Dikes, Aufschiebungen Plattentektonik Vulkanismus an Plattengrenzen Hotspots Eruptionsprodukte Vulkantypen, Oberflächenformen Stagnant-lid regime («one plate planets») Tektonische und vulkanische Entwicklung der Planeten Merkur und Mond Mars Venus E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009

3 Differentiation planetarer Körper E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009

4 Krustentypen from Head, in: New Solar System (????)

5 Bildung einer primären (anorthositischen) Kruste

6 Sekundäre Kruste (Vulkanismus) from Schmincke (2000)

7 Plattentektonik from Schmincke (2000)

8 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Tektonische Störungen courtesy Richard Schultz

9 Glossaries for Structural Geology and Tectonics Peacock, D.C.P. et al. (2000) Glossary of normal faults. Journal of Structural Geology, 22, McClay, K.R. (1992) Glossary of thrust tectonics terms. In: McClay, K.R. (Ed.), Thrust Tectonics. Chapman and Hall, London, pp Biddle. K.T. and Christie-Blick, N. (1985) Glossary strike-slip deformation, basin formation, and sedimentation. In: Biddle. K.T. and Christie-Blick, N. (Eds.), Strike-slip Deformation, Basin Formation, and Sedimentation, Spec. Publ. 37, Soc. Of Economic Mineralogists, pp in deutsch: Meier, D. (1993) Abschiebungen, Enke, Stuttgart.

10 Einfache Gräben (simple grabens) Häufigstes strukturgeologisches Element auf Planetenoberflächen Einfache Oberflächengeometrie 2 parallele, zueinander einfallende Abschiebungen Graben Horst block diagrams from Press & Siever (1985)

11 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Normal faults: Terminology from: Peacock, D.C.P. et al. (2000) Glossary of normal faults. Journal of Structural Geology, 22,

12 "Simple" Grabens on the Moon Apollo AS Apollo AS

13 GoogleEarth GoogleEarth HRSC HRSC Grabens on Earth and Mars E. E. Hauber: Hauber: Vulkanismus Vulkanismus und und Tektonik, Tektonik, Ringvorlesung Ringvorlesung HGF-Allianz HGF-Allianz Planetenentwicklung Planetenentwicklung und und Leben, Leben, TU TU Berlin, Berlin, 23. April 2009

14 Devils Lane Graben Devils Devils Lane Graben Graben

15 Simple Grabens: Previous Models faulting at bimaterial interface (e.g., brittle over quasiplastic rheology) faulted upper layer separated by sills or detachment zones from undeformed substrate graben wedge falling into spaceaccomodation tensile crack in substrate graben faults nucleated by dike dilation at depth from: Schultz et al., in: The Geology of Mars, Cambridge Univ. Press (2007)

16 The new "hourglass" model of planetary simple grabens B B from: Schultz et al., in: The Geology of Mars, Cambridge Univ. Press (2007)

17 from Soliva and Schultz, Tectonics (2008)

18 An elongated tectonic depression associated with which the entire lithosphere has been modified in extension Olsen and Morgan [1996] A discrete topographic depression bounded by a pair of composite border faults, flanked by uplifted topography, and terminated along-trike by topographically high transfer-fault zones and/or volcanics that crosscut the basin Ebinger and Hayward [1996], cited by Schultz [2000] The classical model: The East African Rift System (e.g., Kenya Rift) What is a continental rift segment? E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009

19 Simple Graben Continental Rift MOHO minor structural depression no significant extension lithosphere asthenosphere major structural depression Verschiedene Stile der Extensionstektonik Highly Extended Terrane MOHO extension localized by rifting, commonly asymmetric lithosphere asthenosphere broad zone of extension MOHO extension not localized by welldefined structural depression lithosphere asthenosphere Passive Margin MOHO old continental mantle lithosphere lithosphere asthenosphere continental shelf and slope extended continental crust oceanic crust new continental mantle lithosphere modified from Olsen, Continental Rifts (1996) E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009

20 crust mantle crust mantle crust mantle Modes of Continental Extensional Tectonics Straining region lithosphere asthenosphere lithosphere asthenosphere lithosphere asthenosphere 100 km km km km a narrow rift mode concentrated lithospheric extension narrow regions (~ km wide) of intense normal faulting single basins, normally displaying alternating polarities, arranged en echelon and linked by transfer or accommodation zones b wide rift mode distributed extension (~1000 km wide) large number of separated basins (= Highly Extended Terranes) c core complex mode high-grade metamorphic rocks exposed at the surface exhumed by low-angle normal faults, uplift and erosion modified from Corti et al., Earth Sci. Rev. (2003), after Buck, J. Geophys. Res. (1991) E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin

21 Comparison to terrestrial continental rift from Hauber & Kronberg, J. Geophys. Res. (2001)

22 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin Comparison to terrestrial rifts EARS Venus after McGill et al., Geophys. Res. Lett. (1981)

23 Magma chambers, dikes, and volcanoes from Gudmundsson & Philipp, SdW (2007)

24 Vulkanische Gänge (Dikes) Ship Rock (SW USA)

25 Surface deformation during dike inflation Growth of a pressure ridge immediately above the dike and development of dip slip movement along some of the innermost fissures to form inward facing scarp from Mastin and Pollard, J. Geophys. Res. (1988)

26 Schematic Model of graben evolution from Mastin and Pollard, J. Geophys. Res. (1988)

27 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Dikes can be large! lengths of hundreds of km

28 Examples of Giant Dike Swarms all figures from: Mantleplumes.org Radial patterns with lengths of several 100 km

29 Kontraktionserscheinungen Aufschiebungen (thrust faults) Wrinkle ridges Lobate scarps Fold-and-thrust belt

30 Wrinkle ridges Wrinkle ridges are a wide-spread surface feature on terrestrial planets: Mercury, Moon, Mars, Venus (and Earth!) Mercury Moon Mars from Head et al., Space Sci. Rev. (2007)

31 Lunae Planum, Mars from Mueller & Golombek, Ann. Rev. Earth Planet. Sci. (2004)

32 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Structural models proposed for planetary wrinkle ridges a) Buckle folds with nucleations of thrust faults (Watters, 1988) b) Simple thrust fault c) Conjugate thrust fault (Allemand & Thomas, 1992; Mangold et al., 1998) d) Fault-bend fold (Suppe, 1983; Suppe & Connors, 1992) e) Fault-propagation fold (Mercier et al., 1997) from Schultz, J. Geophys. Res. (2000)

33 Wrinkle ridges: which substrate? E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Lava (Lunar Mare-Basalts) but perhaps possible in sediments

34 E. E. Hauber: Hauber: Vulkanismus Vulkanismus und und Tektonik, Tektonik, Ringvorlesung Ringvorlesung HGF-Allianz HGF-Allianz Planetenentwicklung Planetenentwicklung und und Leben, Leben, TU TU Berlin, Berlin, April April Lobate Scarps: Amenthes Rupes from Watters and Robinson, J. Geophys. Res. (1999)

35 Schematic 3D-view of Contractional Features from Mueller & Golombek, Ann. Rev. Earth Planet. Sci. (2004)

36 from Perfit and Davidson, in: Encyclopedia of Volcanoes (2001)

37 Divergente Plattengrenzen

38 Mittelozeanische Rücken Mid-ocean ridges (MORB) from Press and Siever, Allgemeine Geologie (1995)

39 Transformstörung from Press and Siever, Allgemeine Geologie (1995)

40 Sea-floor ages are progressively older with distance from divergent boundary. If there were an impact crater record, the areal distribution of craters would not be random (as it is on Venus). map of sea floor ages E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009

41 Sea floor spreading: Alternierende Magnetisierung der Ozeanböden from Press and Siever, Allgemeine Geologie (1995)

42 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Symmetrische Magnetisierung from Press & Siever, Allg. Geologie (1995)

43 Konvergierende Plattengrenze

44 Hotspots A»hotspot«is not a synonym for a plume! Are hotsopts underlain by plumes? Evidence from, e.g., seismic tomography For plume sceptics see Iceland after Wolfe et al., Nature (1997), from Schmincke (2000)

45 Hotspot Vulkanismus modified from Press & Siever, Allgemeine Geologie (1995)

46 Inselketten after Dalrymple et al. (1973), from Schmincke (2000)

47 Hotspot trails after Crough (1983), from Schmincke (2000)

48 Age progression of island chains from Hamblin & Christiansen, Earth`s Dynamic Systems (1995)

49 after Hamblin & Christiansen (1995)

50 E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF-Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 from Press and Siever, Earth (1994)

51 Large Igneous Provinces (LIP) after Coffin & Eldholm (1994), modified from Schmincke (2000)

52 Flut- oder Trappbasalte («flood basalts») z.b. Deccan traps, Columbia River, Sibirien)

53 Eruptionsvolumina from Schmincke (2000)

54 Prozentuale Verteilung from Perfit and Davidson, in: Encyclopedia of Volcanoes (2001)

55 Tectonic environments and volcanism from Perfit & Davidson, in: Encyclopedia of Volcanoes (2000)

56 Styles of volcanic eruptions from Wilson & Head, Rev. Geophys. (1994)

57 from Sigurdsson, in: Encyclopedia of Volcanoes (2000)

58 stock Effusiv- und Intrusivgesteine volcano lava flow dike ash falls pyroclastics sill volcanic neck with radiating dikes from Press & Siever (1994)

59 from dkimages.com

60 Vulkanbauten im Größenvergleich from Press & Siever (1994)

61 Schildvulkane (shield volcanoes) häufigster extraterrestrischer Vulkantyp from Press and Siever, Allgemeine Geologie (1995)

62 Klassifikation magmatischer Gesteine from Schmincke (2000)

63 Vulkanische Ausgasung (outgassing) Basalt Rhyolith from Schmincke (2000)

64 Thermal evolution models of planets (e.g., Mars) from Spohn et al., Astron. Astrophys. (2001) E. Hauber: Planetare Strukturgeologie und Tektonik (V 24042; WS 07/08)

65 Density [kg m -3 ] Mercury (large iron core) Earth Venus E. Hauber: Vulkanismus und Tektonik, Ringvorlesung HGF- Allianz Planetenentwicklung und Leben, TU Berlin, 23. April 2009 Radiusdensity relation of terrestrial planets Io Moon Mars from Sohl & Schubert, Treatise on Geophysics (2007) Radius [km]

66 from Head, in: New Solar System

67 Thermal evolution of planets Early stage (heating) Later stage (cooling) from Solomon (1975)

68 One plate planets from Solomon (1975)

69 Predicted stresses on a despun planet Model based on changing oblateness of planet but does not agree with observations from Melosh, Icarus (1977)