550 Earth sciences
551 Geology, hydrology, meteorology
552 Petrology
553 Economic geology
554-559 Earth sciences by specific continents, countries, localities in modern world; extraterrestrial worlds
560 Paleontology
561 Paleobotany; fossil microorganisms
562 Fossil invertebrates
563 Miscellaneous fossil marine and seashore invertebrates
564 Fossil Mollusca and Molluscoidea
565 Fossil Arthropoda
566 Fossil Chordata
567 Fossil cold-blooded vertebrates
568 Fossil Aves (birds)
569 Fossil Mammalia