Antarctic Gravity Anomaly Intensifies Over 70 Million Years
Researchers have traced the Antarctic Geoid Low's evolution, revealing its persistence and intensification over 70 million years due to mantle dynamics.
Scientists have reconstructed the 70-million-year evolution of the Antarctic Geoid Low (AGL), Earth's most significant nonhydrostatic geoid depression, revealing its persistence and intensification over time. The AGL, a subtle gravity anomaly centered over the Ross Sea between Victoria Land and Marie Byrd Land, reflects variations in Earth's gravity field and influences sea-surface height.
The study, published in Scientific Reports, utilized mantle-convection modeling constrained by seismic-tomography-based density structures to trace the AGL's development. Findings indicate that the anomaly has existed for at least 70 million years, undergoing significant shifts in position and strength between approximately 50 and 30 million years ago.
Understanding the AGL's evolution offers insights into Earth's internal dynamics and their impact on surface phenomena, including sea-level variations and ice sheet stability. The research underscores the interconnectedness of deep Earth processes and surface environmental changes.