Science Crossword

3. all the waters on the earth's surface, such as lakes and seas, and sometimes including water over the earth's surface, such as clouds.
5. the movement caused within a fluid
7. The theory that pieces of Earth’s lithosphere are in constant motion, driven by convection currents in the mantle.
8. A plate boundary where two plates move past eachother in opposite directions.
9. The hypothesis that the continents slowly move across Earth’s surface.
12. A deep valley that forms where two plates move apart.
14. A plate boundary where two plates move toward eachother.
16. A system for the detection for objects underwater and for measuring the waters depth by emmiting sound pulses and detecting or measuring their return of being reflected.
18. The process by which molten material adds new oceanic crust
19. Composed of a great variety of igneous, metamorphic, and sedimentary rocks.
20. An undersea mountain chain where new ocean floor is produced; a divergent plate boundary.

1. Earth’s innermost part
2. The preserved remains or traces of an organism that lived in the past.
4. a deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle.
6. the processes that build up the Earth's surface to deposit sediments and create new land forms.
10. A very hard granular crystalline igneous rock.
11. two tectonic plates that are moving away from each other
13. Rift valleys that have been stretched or
15. The name of the single landmass that began to break apart 200 million years ago and gave rise to today’s continent.
17. A dark fine grained volcanic rock