In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

The distribution of these events is the subject of the Mogi donut hypothesis. The mechanism of these events can be calculated using a "beach ball" diagram, and such mechanisms include the double-couple source. The frequency of these events is given by an equation setting that value equal to 10 to the power of a minus bM, which is a law partly named for Gutenberg and notably doesn't apply during "swarms" of these events. The VAN method attempts to predict these events by using low-level (*) electrical signals. One theory about these events proposes that they are caused by strain energy being spontaneously released; that idea was posited by Harry Fielding Reid and is called the elastic rebound hypothesis. Another common method of predicting them measures anomalies in the ratio of P-wave to S-wave velocity, and the MMS has largely replaced the scale previously used to measure these events, which is a log-base-10 scale. For 10 points, name these events whose severity is measured by the Richter scale.
History