Deeper earthquake focal points result in higher magnitude earthquakes

Introduction: The depth-focal points of earthquakes can determine the likelihood of how light or strong, in terms of magnitude, an earthquake is likely to be. This may be a factor in determining where or how critical-infrastructure buildings, such as hospitals or prisons, can be better built to withstand stronger earthquakes, should they lie on or near deeper-earthquake starting focal points. Objectives: The primary objective of this project is to see if there is a correlation between earthquake depth and intensity of earthquakes in both Northern and Southern California, using a sample data of earthquakes from the last 20 years. With the same data available, our secondary objective will be to compare the number and intensities of earthquakes for Northern and Southern California. Methods: Upon obtaining the dataset of earthquakes from the Incorporated Research Institutions for Seismology (IRIS), we will query earthquakes greater than 4.0, and within the last 20 years. IRIS provides a map visual of the area of interest for data to be downloaded. In this case, we will zoom into the western United States. OpenRefine (v. 3.5) will be used to filter only earthquakes in Northern California and Southern California, by applying a text facet to the data. Descriptive analysis will be displayed using Tableau to see if there are any correlations, as well as to make comparisons between Northern and Southern California. Results: As a result of plotting the data, we can see that there is a statistically slight positive relationship between earthquake depth and magnitude. The majority of the smaller earthquakes seem to suggest that they have a more-shallow focal point as compared to the larger earthquakes, which have a deeper focal point. Conclusions: Critical infrastructure, as well as general housing, should be avoided in areas where deeper earthquakes are likely to occur, as these most likely will result in stronger, more-intense earthquakes.