Across
- 3. a supercontinent that existed during the late Paleozoic and early Mesozoic eras.
- 4. a subsea chasm extending along the crest of a mid-ocean ridge, locus of the magma upwellings that accompany seafloor spreading.
- 6. theory of global tectonics in which the lithosphere is divided into a number of crustal plates, each of which moves on the plastic asthenosphere more or less independently to collide with, slide under, or move past adjacent plates.
- 11. magnetic polarization acquired by the minerals in a rock at the time the rock was deposited or solidified.
- 12. a line on an isotope ratio diagram denoting a suite of rock or mineral samples all formed at the same time. The slope of the line is related to the age of the rock or mineral suite
- 14. is the portion of motion of a tectonic plate that can be accounted for by its subduction. Plate motion is partly driven by the weight of cold, dense plates sinking into the mantle at trenches.
- 15. a linear feature that exists between two tectonic plates that are moving away from each other.
Down
- 1. a process in which new ocean floor is created as molten material from the earth's mantle rises in margins between plates or ridges and spreads out.
- 2. a strike-slip fault that offsets a mid-ocean ridge in opposing directions on either side of an axis of seafloor spreading.
- 5. A change in the Earth's magnetic field resulting in the magnetic north being aligned with the geographic south, and the magnetic south being aligned with the geographic north.
- 7. a major geologic discontinuity or suture marking the juncture of lithospheric plates that have been joined by plate tectonics.
- 8. the process by which collision of the earth's crustal plates results in one plate's being drawn down or overridden by another, localized along the juncture of two plates.
- 9. the lateral movement of continents resulting from the motion of crustal plates.
- 10. an instrument for measuring the intensity of a magnetic field, especially the earth's magnetic field.
- 13. the long and narrow upper edge, angle, or crest of something, as a hill, wave, or vault.