Brought to you by BioInnovation Institute & Science Prize for Innovation | |
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| | First Release | Accepted papers posted online prior to journal publication |
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| RESEARCH ARTICLE | Ice sheet–free West Antarctica during peak early Oligocene glaciation | BY J. P. KLAGES, C.-D. HILLENBRAND, ET AL. | 4 JUL 2024 | One of Earth’s most fundamental climate shifts – the greenhouse-icehouse transition 34 Ma ago – initiated Antarctic ice-sheet build-up, influencing global climate until today. However, the extent of the ice sheet during the Early Oligocene Glacial Maximum (~33.7–33.2 Ma) that immediately followed this transition, a critical knowledge gap for assessing feedbacks between permanently glaciated areas and early Cenozoic global climate reorganization, is uncertain. Here, we present shallow-marine drilling data constraining earliest Oligocene environmental conditions on West Antarctica’s Pacific margin – a key region for understanding Antarctic ice sheet-evolution. These data indicate a cool-temperate environment, with mild ocean and air temperatures preventing West Antarctic Ice Sheet formation. Climate-ice sheet modeling corroborates a highly asymmetric Antarctic ice sheet, thereby revealing its differential regional response to past and future climatic change. | |
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RESEARCH ARTICLE | Slow rupture in a fluid-rich fault zone initiated the 2024 Mw 7.5 Noto earthquake | BY ZHANGFENG MA, HONGYU ZENG, ET AL. | 4 JUL 2024 | The 2024 moment magnitude (Mw ) 7.5 Noto Peninsula (Japan) earthquake caused devastation to communities and was generated by a complex rupture process. Using space geodetic and seismic observations, we show that the event deformed the peninsula with a peak uplift reaching 5 m at the west coast. Shallow slip exceeded 10 m on an offshore fault. Peak stress drop was greater than 10 MPa. This devastating event began with a slow rupture propagation lasting 15-20 s near its hypocenter, where seismic swarms had surged since 2020 due to lower-crust fluid supply. The slow start was accompanied by intense high-frequency seismic radiation. These observations suggest a distinct coseismic slip mode reflecting high heterogeneity in fault properties within a fluid-rich fault zone. | |
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| | | Brought to you by BioInnovation Institute & Science Prize for Innovation | |
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