codi
Across
- 4. the branch of geophysics concerned with the magnetism in rocks that was induced by the earth's magnetic field at the time of their formation.
- 5. the formation of new areas of oceanic crust, which occurs through the upwelling of magma at midocean ridges and its subsequent outward movement on either side.
- 6. a theory in geology: the lithosphere of the earth is divided into a small number of plates which float on and travel independently over the mantle and much of the earth's seismic activity occurs at the boundaries of these plates.
- 9. an extensional boundary) is a linear feature that exists between two tectonic plates that are moving away from each other.
- 11. a strike-slip fault that offsets a mid-ocean ridge in opposing directions on either side of an axis of seafloor spreading.
- 13. the gradual movement of the continents across the earth's surface through geological time.
- 14. the portion of motion of a tectonic plate that can be accounted for by its subduction.
- 15. an instrument used for measuring magnetic forces, especially the earth's magnetism.
Down
- 1. a large elongated depression with steep walls formed by the downward displacement of a block of the earth's surface between nearly parallel faults or fault systems.
- 2. an actively deforming region where two (or more) tectonic plates or fragments of the lithosphere move toward one another and collide.
- 3. the sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate.
- 7. supercontinent that existed during the late Paleozoic and early Mesozoic eras.
- 8. a line on a diagram or map connecting points relating to the same time or equal times.
- 10. Changes in direction or orientation of the magnetic field of the Earth that have occurred from time to time.
- 12. a proposed mechanism for plate motion in plate tectonics.