Resan till jordens inre. Athanasius Kircher(1665) Mundus Subterraneus Jules Verne (1864)

Storlek: px

Starta visningen från sidan:

Download "Resan till jordens inre. Athanasius Kircher(1665) Mundus Subterraneus Jules Verne (1864)"

Emil Gustafsson
för 7 år sedan
Visningar:

1 Resan till jordens inre Athanasius Kircher(1665) Mundus Subterraneus Jules Verne (1864)

2 Nuvarande schematisk bild av jordens inre

3 Temperatur i jordens inre

4 Tryck i jordens inre 400 Tryck och densitet profiler i jordens inre 14 Djupaste hav Industri Max. tryck i Jorden Diamancell Max. tryck i Jupiter Explosion av kärnvapen Solens kärna 0.1 GPa 3 GPa 364 GPa 550 GPa 2 TPa 100 TPa TPa Pressure (GPa) Density (g/cm3) 50 0 mantle outer core inner core Depth (km) 1 GPa = N / cm 2 järn 0 GPa järn 364 GPa

5 Studier av jordens inre med hjälp av seismiska vågor

6 Density, pressure and gravity within the Earth

8 Key questions of the Earth s deep interior rely on high pressure experiments

9 fältspat Silikater olivin kvarts pyroxen granat

10 hematit (Fe 2 O 3 ) pyrit (FeS 2 ) koksalt (NaCl) gips (CaSO 4. 2H 2 O)

i manteln Vad händer med strukturen av en silikat mineral när tryck

11 Subduktionszon (neddykningszon) - en långsmal zon i jordskorpan längs vilken två litosfäriska plattor kolliderar varvid den ena tvingas ned i manteln Vad händer med strukturen av en silikat mineral när tryck och temperatur ökar vid neddykning i subduktionszonen? gips (CaSO 4. 2H 2 O)

025 % of Earth s mass Chondrites contain 0.

12 Vatten i jordens inre Range of water concentrations in mantle-derived samples clinopyroxene Oceans cover 71% of surface Only % of Earth s mass Chondrites contain 0.10% H 2 O orthopyroxene garnet olivine ppm H 2 O Olivine, enstatite, diopside and garnet make up 95% of the upper mantle. They all contain water.

13 olivin Fasövergångar hos olivin

15 quartz Coesite inclusions in Pyrope. Size of Pyrope is about 10x7 mm Coesite inclusion in garnet of eclogite sample Coesite is a form of silicon dioxide that is formed when very high pressure (2 3 gigapascals) and moderately high temperature (700 C) are applied to quartz. Coesite was first created by in In 1960, coesite was found by Eugene Shoemaker to naturally occur in the Barringer Crater, which was evidence that the crater must have been formed by an impact. The presence of coesite in unmetamorphosed rocks may be evidence of a meteorite impact event or of an atomic bomb explosion. In metamorphic rocks, coesite commonly is one of the best mineral indicators of metamorphism at very high pressures (UHP, or ultrahigh-pressure metamorphism). Such UHP metamorphic rocks record subduction or continental collisions in which crustal rocks are carried to depths of 70 km or more. Coesite also has been identified in eclogite xenoliths from the mantle of the earth that were carried up by ascending magmas; kimberlite is the most common host of such xenoliths. The molecular structure of coesite consists of four silicon dioxide tetrahedra arranged in a ring. The rings are further arranged into a chain. This structure is metastable within the stability field of quartz: coesite will eventually decay back into quartz with a consequent volume increase, although the metamorphic reaction is very slow at the low temperatures of the Earth's surface.

16 Stishovite a high pressure polymorph of SiO 2 The structure is dense-packed. Unlike in quartz, where Si-O are arranged in a tetrahedral coordination, in stishovite each silicon atom has 6 oxygen neighbours (octahedral coordination) Tiny (< 1 mm) greyish-white, roundish aggregates of the high pressure mineral Stishovite on a matrix of Magadiite-Kenyaite-Coesite. Field of view 3 mm. The source of 'forming' the Stishovite was extreme heat by an meteorite impact near Bisbee, Arizona. The exact location and the year of impact is unknown.

17 Examples of some high pressure high temperature phase diagrams of minerals determined in laboratory Phase diagrams depict P-T ranges of stability of various crystallographic forms of minerals. Phase diagram of MgSiO 3 (At ambient conditions, MgSiO 3 represents mineral enstatite, belonging to the pyroxene group of silicates)

18 Examples of some high pressure high temperature phase diagrams of minerals determined in laboratory Phase relationships for SiO 2 (quartz at ambient conditions) Phase diagram of NaAlSi 3 O 8 (feldspar albite at ambient conditions)

19 Tryck = kraft / yta Diamantcell öppnar ett fönster till jordens inre

20 Prov i diamantcell

21 Laseruppvärmning av material i diamantcell

22 Laseruppvärmning av material i diamantcell iron at high pressure in diamond anvil cell Bilder på glödande provet 50 microner

23 Fasdiagram av kol Omvandling av grafit till diamant i diamantcell vid högt tryck och temperatur

24 Determination of crystal structure by x-ray diffraction Fig W. W. Norton By analyzing diffraction pattern, crystal structure of mineral can be determined

25 Synkrotron anläggningar används ofta för högtryckstudier. Synkrotron i Argonne, USA. Synkrotron i Grenoble, Frankrike.

27 Discovery of post-perovskite transition in MgSiO 3 - A new paradigm for core-mantle boundary Murakami et al., Science (2004) CMB 3500 Temperature (K) Orthorombicperovskite 7.5 MPa/K Post-Pv 500 error ~5 GPa Pressure (GPa) Hill top ~8 GPa ~250 km Valley bottom

28 D lager MgSiO 3 perovskite Post-perovskite Si Mg

29 Kristallstruktur av post-perovskit Si Mg

30 Perovskite The dominant mineral on the Earth Post-Perovskite Forms 150 km thick layer adjacent to the core

32 Framsteg i forskning om jordens inre Year-points mark the time and depths, for which corresponding experimentral pressure-temperature conditions were reached in the laboratory. Modern tomographic 3-D image of the Earth. Colors encode speesd of seismic waves; blue for faster-than average; red for slower-than average speeds. These variations are connected to changes in temperature and/or chemical composition.

Relevanta dokument

The Arctic boundary layer

The Arctic boundary layer Interactions with the surface, and clouds, as learned from observations (and some modeling) Michael Tjernström Department of Meteorology & the Bert Bolin Center for Climate Research,