Geoscience Crossword

3. Determining the relative order of past events or objects
4. Waves of energy that travel through the Earth's layers
7. An absences of oxygen
10. Branch of science studying earthquakes
14. Dating rocks using the relative proportions of particular radioactive isotopes
15. The presence of oxygen
19. Branch of science studying the magnetism in rocks
20. Process that help build up the Earth

1. Meteor that survives its passage through the Earth's atmosphere and hits the ground
2. Representation on a map of the natural and artificial features of an area
5. Different forms of the same element that have a different number of nuetrons
6. A living factor
8. The true age of a rock or fossil
9. Movement in a fluid where hotter and less dense matter rises and colder and less dense matter sinks
11. A non-living factor
12. Time taken for the isotope to decrease into half its original value
13. Forms the nuclear mass of a continent or the central basin of an ocean
16. Close relationship of two factors that cause them to impact how each other change
17. process by which rock is broken down, such as erosion and weathering
18. Process where the nucleus of an unstable atom loses energy by emitting radiation