Final answer:
The Atlantic Ocean is currently in an expansion phase of the supercontinent cycle, with its tectonic plates diverging at the Mid-Atlantic Ridge, marking a relatively young stage in the cycle.
Step-by-step explanation:
The present stage of the Atlantic Ocean in the supercontinent cycle is one of expansion or growth. Approximately 200 million years ago, the supercontinent Pangea began to fragment, leading to the formation and ongoing widening of the Atlantic Ocean. This process is driven by the divergent tectonic activity at the Mid-Atlantic Ridge, where the European and North American plates, as well as the South American and African plates, are gradually drifting apart.
Based on the observed rate of drift between Europe and North America, which is about 5 centimeters per year, we can infer that similar forces are at work along the entirety of the Mid-Atlantic Ridge, contributing to the continuous creation of new ocean floor. This geological activity forms part of the long-cycle pattern of supercontinent formation and breakup known as the supercontinent cycle. The Atlantic Ocean's current expansion phase is a relatively young stage in the cycle, expected to continue for many millions of years until eventually, tectonic forces may change and lead to a new phase of convergence.