研究者らは、南極の下にある異常な重力の穴が、数百万年にわたる地球深部の岩石のゆっくりとした動きによって形成されたことを明らかにした。この異常は5000万～3000万年前に強まり、大陸の気候変動と一致していた。この発見は、地球内部が海面や氷床などの地表条件に与える影響についての洞察を提供する。
地球表面では重力がわずかに変動し、最も注目すべき異常の一つが南極の下にあり、そこで重力は予想よりも弱い。Scientific Reportsに掲載された研究によると、この「重力の穴」は地表遠く下部の岩石密度の徐々な変化によって生じ、数千万年にわたって発生した。
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Bright pink granite boulders on Antarctica's Hudson Mountains have unveiled a massive buried granite body beneath Pine Island Glacier. The structure measures nearly 100 km wide and 7 km thick. Researchers linked the rocks, dated to 175 million years ago, to this subglacial feature using gravity surveys.
Scientists using deep-diving Argo floats have pinpointed the reason behind Antarctica's dramatic sea ice contraction starting in 2016. The decline stems from a violent release of pent-up heat from ocean depths, triggered by shifting winds and salinity changes. This discovery highlights the ocean's key role in sea ice variability.
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New data from the European Space Agency's Swarm satellites reveal that the South Atlantic Anomaly, a weak spot in Earth's magnetic field, has grown by nearly half the size of continental Europe since 2014. A region southwest of Africa is weakening even faster in recent years. This expansion highlights unusual activity in Earth's molten outer core.
Scientists have detected traces of iron-60 in Antarctic ice up to 80,000 years old, showing that the solar system is moving through material from an ancient stellar explosion. The findings come from a study published in Physical Review Letters and point to the Local Interstellar Cloud as the source of the radioactive isotope.
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In 2023, Hektoria Glacier on Antarctica's Eastern Peninsula retreated eight kilometers in just two months, marking the fastest such event recorded. Nearly half of the glacier broke apart due to its position over a flat underwater bedrock. The discovery, detailed in a new study, highlights vulnerabilities in other Antarctic ice features.
New research has resolved a long-standing debate, confirming that the Silverpit Crater beneath the North Sea resulted from an asteroid strike about 43 to 46 million years ago. The impact generated a tsunami over 100 meters high. Led by Dr. Uisdean Nicholson of Heriot-Watt University, the study used seismic imaging and shocked minerals to provide definitive evidence.
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A major Atlantic Ocean current system that regulates global climate has been slowing down for nearly 20 years. New research provides direct evidence of the decline across a wide area of the North Atlantic.