備註請放最後面 違者新聞文章刪除 1.媒體來源: 外媒 NewScientist 2.記者署名: James Woodford 詹姆斯‧伍德福德 3.完整新聞標題: Earth’s geographic poles wander more than we had thought 地球地理極點的移動幅度比之前想像更劇烈 4.完整新聞內文: Earth’s geographic poles wander more than we had thought 地球地理極點的移動幅度比之前想像更劇烈 A phenomenon known as true polar wander, different to the movement of the magnetic poles, may be more common and more dramatic than previously known True colour satellite image of the Earth The Earth’s geographic poles – the points where the imaginary axis of the planet’s rotation is located – may be far less immutable than previously known, with a new study finding that ancient sea-level changes provide a clue to their movement. Earth has two main pairs of poles: its magnetic poles, resulting from its magnetic field, and its geographic poles based on its rotation. The magnetic poles are constantly in movement and are often hundreds of kilometres away from the geographic north and south poles. They can even flip altogether. 一種被稱為真極漂移的現象，不同於磁極的移動，可能比之前所知的更為普遍和顯著。 作者：詹姆斯‧伍德福德 2026年10月1日 一項新的研究發現，地球的地理極點（即地球自轉軸所在的假想點）可能遠沒有之前人們 所認為的那麼固定不變，古代海平面變化為了解其運動提供了線索。 地球有兩對主要的極：由磁場產生的磁極和基於自轉產生的地理極。磁極不斷移動，通常 與地理南北極相距數百公里，甚至會完全翻轉。 The geographic poles are much more stable. But they can move a little, through a phenomenon called true polar wander. This is driven by the way plate tectonics and mantle convection slowly redistribute mass in Earth’s mantle and affect the planet’s spin. When the spin of the planet is thrown out of whack, the solid outer layers of the globe begin to movein order to help Earth find a new stable spin equilibrium. This has the effect of moving the geographic poles. “The crust and the mantle effectively slip over the core during a true polar-wander event,” says Mathew Domeier at the University of Oslo in Norway. However, until now much of the evidence for true polar-wandering events has come from ancient magnetic data locked inside rocks that formed millions of years ago, and this evidence has yielded confusing and conflicting results about the frequency and scale of the events. So, Domeier and his team took a different approach. They analysed the geological record of sea-level change looking for distinctive signals that might be expected during a true polar-wander event. 地理極點相對穩定得多。但它們也會發生輕微移動，這種現象稱為真極移。真極移是由板 塊構造和地函對流緩慢地重新分配地球地函中的物質，並影響地球自轉而所造成的。 當地球自轉軸被打亂時，地球的固體外層就會開始移動， 以幫助地球找到新的穩定自轉 平衡。這會導致地理極點的移動。 「在真正的極移事件中，地殼和地函會有效地滑過地核。」 挪威奧斯陸大學的馬修·多梅爾說。 然而，到目前為止，關於真正的極移事件的大部分證據都來自數百萬年前形成的岩石中保 存的古代磁性數據，而這些證據對於極移事件的頻率和規模得出了令人困惑和相互矛盾的 結果。 因此，多梅爾和他的團隊採取了不同的方法。他們分析了海平面變化的地質記錄，尋找在 真正的極移事件中可能出現的獨特訊號。 Because of the way ocean water can more quickly adjust to the centrifugal potential changes than the rocky sea floor, true polar-wander events are expected to leave a telltale pattern. Sea level will rise in one half of the northern hemisphere and fall in the other half, and it will also rise in one half of the southern hemisphere and fall in the other half. The northern and southern hemisphere signals are reversed, however, so if it is the western side of the northern hemisphere that experiences sea-level rise, it will be the eastern side of the southern hemisphere that does so, too, creating a beach ball-like global pattern. “This is a very strange pattern that is not caused by other Earth processes, ” he says. On the time scales we experience, the events would be unnoticeable. But over longer periods of geological time, a wandering pole changes the distribution of land and sea. 由於海水比岩石海底能更快適應離心勢的變化，真正的極移事件預計會離開這是一個明顯 的規律。北半球一半地區的海平面會上升，另一半地區會下降；南半球一半地區的海平面 也會上升，另一半地區會下降。 然而，南北半球的訊號是相反的，因此，如果北半球的西側經歷海平面上升，那麼南半球 的東側也會經歷海平面上升，形成類似沙灘球的全球模式。 「這是一種非常奇怪的模式，並非由地球上的其他過程引起，」他說。 在在我們所處的時間尺度上，這些事件幾乎難以察覺。但在較長的地質時期內，地磁極的 漂移會改變陸地和海洋的分佈。 For instance, from their analysis of ancient sea-level patterns, Domeier and his colleagues discovered that the geographic poles moved dramatically, over periods of around 10 million years, four times in the geological past: at 20, 90, 140 and 190 million years ago. “By the timescales of human experience, the movement may not seem fast,” says Domeier. “We cannot estimate the exact speed, but we can recognise events where the rate of polar motion exceeded about 0.6 degrees per million years.” He says this is faster than the rate at which most tectonic plates move – fast enough to potentially have an effect on climate systems. What’s more, we know that true polar wandering continues today, although maybe not at the rate seen during the four fast bursts in the geological past. 例如，多梅爾和他的同事透過分析古代海平面模式發現，地理極點在地質歷史上曾發生過 四次劇烈移動，每次移動週期約為 1000 萬年：分別發生在 2000 萬年前、9000 萬年前 、1.4 億年前和 1.9 億年前。 「以人類經驗的時間尺度來看，這種運動可能看起來並不快，」多梅爾說。 “我們無法 估算其確切速度，但我們可以識別出極移速度超過某個閾值的事件。”大約每百萬年變化 0.6攝氏度。 他表示，這比大多數構造板塊的移動速度還要快—快到足以對氣候系統產生影響。 此外，我們知道真正的極移現象至今仍在發生，儘管其速度可能不如地質歷史上四次快速 極移爆發期間的速度那麼快。 “[It] is measurable by satellites at a rate of about 10 cm per year, but most people are unaware of this. So these events are totally unrecognisable according to our everyday experience,” says Domeier. Sabin Zahirovic at the University of Sydney says very few people are aware that Earth’s 2800-km-thick outer shell of the crust and mantle are in motion with respect to Earth’s spin axis. The study demonstrates that clues in the coastline change provide an independent fingerprint of true polar wander. “This is a very exciting development that helps us link very deep Earth processes to changes in long-term climate and sea level on the planet,” says Zahirovic. 「衛星可以測量到這種變化，速度約為每年10厘米，但大多數人對此並不知情。因此，根 據我們的日常經驗，這些事件是完全無法識別的，」多梅爾說。 雪梨大學的薩賓·扎希羅維奇說非常很少人意識到，地球厚達 2800 公里的地殼和地函外 殼相對於地球自轉軸處於運動狀態。 該研究表明，海岸線變化中的線索可以獨立地反映出真正的極移現象。 扎希羅維奇說：“這是一個非常令人興奮的進展，它有助於我們將地球深處的地質過程與 地球長期氣候和海平面的變化聯繫起來。” 期刊參考文獻： 科學 DOI：10.1126/science.aec8423 https://www.science.org/doi/10.1126/science.aec8423 5.完整新聞連結 (或短網址)不可用YAHOO、LINE、MSN等轉載媒體: https://reurl.cc/eQA8WM 6.備註: 原來恐龍時代的超級地幔柱，早就因為不明機制整整翻轉過四次啦？ https://i.urusai.cc/O1zFX.jpg https://youtu.be/aorjk2g3tqs?si=lGTJmjPG0sHaKB7g&t=1140 -- https://www.youtube.com/watch?v=m-QXmqX7k8Q 劉德華 悟 電影【新少林寺】主題曲 https://youtu.be/dLRLWy7bKS4 作曲：趙欽 作詞：劉德華 《金剛總持祈請文》 編曲：Adam Lee．飾墜．陳德建 蔣巴桑波 (第七世噶瑪巴確扎嘉措之根本上師) 著 監製：陳德建．李安修 不要把金王冠織入鳥巢中 招惹微風與獵槍是不明智的 依常斷見所立宗 能壞慧命因緣法 精勤十善一夜盡 縱生天人多闡提 --

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