 Dispersion of the Gondwana continents  Closing of Tethys Ocean  Pacific System: rimmed by subduction zones East Pacific Rise moving towards the Americas Western Pacific island arcs Major tectonic systems

I. Fragmentation of the Gondwana super-continent  Creation of new Oceans Atlantic Indian circum-Antarctic formation of passive margins  Closing of Tethys Ocean: complex Mediterranean – Middle East interactions major continental collisions in central Asia Australian-SE Asian collisions Major tectonic systems operating during the past 200 My

# Ma Middle Eocene Drake Passage Indian Pacific connection

# Ma Early Oligocene Drake Passage Indian Pacific connection

#6, 20.5 Ma Early Miocene Drake Passage Indian Pacific connection

Drake Passage Indian Pacific connection

Formation of Circum-Antarctic Current >> isolation of Antarctica >> formation of ice sheet circum-Antarctic Current

Formation of North Atlantic Deep water (thermo-haline convection system)

Formation of continental passive margins continental shelf

continental passive margins thinned continental crust Sedimentation on subsiding continental shelf oceanic crust

I. Fragmentation of the Gondwana super-continent  Creation of new Oceans Atlantic Indian circum-Antarctic formation of passive margins  Closing of Tethys Ocean: complex Mediterranean – Middle East interactions major continental collisions in central Asia Australian-SE Asian collisions Major tectonic systems operating during the past 200 My

Complex intra-continental Mediterranean-central Asian “plate boundary” Indonesian (Sunda- Banda) island arc Earthquake depth 0-33 km

Topography for previous slide: note complex topography of Mediterranean- central Asian “plate boundary”.

India moving northwards

Himalayan evolution

Indention of India into Asia The named dashed and dotted lines represent boundaries between terranes successively accreted to Asia. The accretion increases in age to the north: Indus Tsangbo, 40 Ma Banggong,160 Ma Jinsha, 200 Ma Kunlun, 255 Ma Tienshan, late Paleozoic The indentation has moved these sutures northwards The dotted areas show the regions of shearing that accomodated the northward indentation of India

Tibetan plateau models

Region of theTibetan Plateau Ignore white rectangle. The blue line shows the approximate location of the section shown in the third slide after this one.

A recently published geological cross section See the section line (blue line) on the map shown in the third preceding slide. From Yin, A. and T.M. Harrison, 2000, Geologic Evolution of the Himalayan-Tibetan Orogen, Ann. Rev. Earth Planet. Sci., v.28,

Central Asian active tectonics

II. Pacific System  East Pacific Rise (EPR) moving towards the Americas and away from Asia  Hot spot tracks  Rimmed by subduction zones Western Pacific Subducting old oceanic lithosphere Formation of back-arc basins and island arcs Eastern Pacific Subducting young oceanic lithosphere Andean type mountain building Collision and accretion of exotic terranes Collision of EPR with North America Major tectonic systems operating during the past 200 My

East Pacific Rise

II. Pacific System  East Pacific Rise (EPR) moving towards the Americas and away from Asia  Hot spot tracks  Rimmed by subduction zones Western Pacific Subducting old oceanic lithosphere Formation of back-arc basins and island arcs Eastern Pacific Subducting young oceanic lithosphere Andean type mountain building Collision and accretion of exotic terranes Collision of EPR with North America Major tectonic systems operating during the past 200 My

Northwestern Pacific Subduction zones: seismicity Izu-Bonin- Marianas island arc Aleutian Island arc Ryukyu island arc Kurile- Kamchatka island arc N. Honshu subduction zone Earthquake depth 0-33 km

Northwestern Pacific Subduction zones: bathymetry

New Zealand New Britain Island arc Vanuatu island arc Tonga island arc Kermadec island arc Southwestern Pacific Subduction zones: seismicity Earthquake depth 0-33 km

Southwestern Pacific Subduction zones: bathymetry

II. Pacific System  East Pacific Rise (EPR) moving towards the Americas and away from Asia  Hot spot tracks  Rimmed by subduction zones Western Pacific Subducting old oceanic lithosphere Formation of back-arc basins and island arcs Eastern Pacific Subducting young oceanic lithosphere Andean type mountain building Collision and accretion of exotic terranes Collision of EPR with North America Major tectonic systems operating during the past 200 My