Final answer:
Global transgressions and regressions refer to the rise and fall of sea levels over geological time. there is no precise number for these events as they are influenced by various factors and are continuous processes. stratigraphic records are used to study and interpret these changes.
Step-by-step explanation:
When discussing global transgressions and regressions, we are referring to the geological processes that involve the rise and fall of sea levels over time. Unfortunately, there is no definitive answer to the exact number of major global transgressions and regressions that have occurred throughout Earth's history as these processes are dynamic and can be influenced by a variety of complex factors such as tectonics, climate change, and glaciation cycles.Evidence of these transgressions and regressions can be observed in the stratigraphic record, where shifts in depositional environments are preserved in the rock layers.
By studying these stratigraphic columns, geologists can interpret historical sea-level changes and understand the impacts they have had on Earth's history.It's important to recognize that the study of transgressions and regressions is a continuous process, with researchers constantly refining our understanding of past sea-level events as new evidence emerges.