https://www.youtube.com/watch?v=-v_RLRT9930
https://www.youtube.com/watch?v=3aLyn_kiMg8
https://www.youtube.com/watch?v=NwT1e8R4hz0
https://www.youtube.com/watch?v=FN6QX43QB4g
https://www.youtube.com/watch?v=A1J4FHDW0-c
https://www.theguardian.com/world/video/2013/aug/23/louisiana-sinkhole-swallows-trees-video
https://www.youtube.com/watch?v=YAMrRZlb3X0
Physical Weathering: ice expanding, wind, rain, frost, thawing, farming, construction, waves
chemical weathering: acid rain, oxidation, temperature/heat/pressure/fire, salt wedging (salt expands in cracks in rocks and cracks them)