Paleoecological Patterns of Reef Death and Possible Causes for the Carbonate Collapse at the End-Triassic Mass Extinction
Coral reefs are extraordinarily sensitive to environmental perturbations, and so the interactions of ancient reef organisms and their ecosystems provide important clues to understanding extinctions, as well as factors controlling reef growth and ecology. In this study, eastern Panthalassic reefs located in Nevada and Oregon (Norian, 217-204 mya), and the Yukon Territory, Canada (Rhaetian, 204-200 mya) were visited, and their paleoecology assessed using quadrate analyses and line intercept transects where applicable. These detailed results of reef paleoecology before the end-Triassic extinction provide valuable information regarding environmental conditions and stresses, which can be used to determine the factors controlling the collapse of these carbonate ecosystems. Today, reefs are undergoing major die-off, commonly attributed to elevated nutrients, ocean acidification, climate change, and other factors comparable to proposed conditions in the Late Triassic. The thorough understanding of analogous reef crises can provide valuable information pertinent to the current crisis with respect to the cause, severity, and extent of a forthcoming extinction.