評論
打印
Throughout history, people have viewed springs as mystical.
縱觀歷史，人們都認為泉水是神秘的。
From the warm pools of Roman Bath, whence sheets of lead inscribed with prayers have been recovered,
從羅馬浴場溫暖的水池（刻有祈禱文的鉛片在那里被發現）
to the gassy waters beneath the Oracle of Delphi that are thought to have stimulated the visions experienced by Apollo's sacred priestesses,
到德爾斐神諭下面的氣體（被認為促使了阿波羅的神圣女祭司所經歷的幻象）
these sites have been sought out for purposes of divination.
尋找這些地點的目的都是為了占卜。
With a modern twist, this is still happening, for Jason Ricketts of the University of Texas at El Paso thinks
隨著現代科技的發展，這種情況仍在發生，厄爾巴索德克薩斯大學的詹森·里基茨認為
the remnants of ancient springs can be used to help monitor climates of the past by dating when warm and cold periods occurred.
古代泉水的遺跡可以用來幫助監測過去的氣候，方法是確定溫暖期和寒冷期的年代。
Dr Rickett's starting point is his assumption that, as ice ages end and the world warms up,
里基茨博士的出發點是他的一個假設—隨著冰河時代的結束，世界變暖，
underground water flows will increase simultaneously all around the planet.
地球各地的地下水流量將同時增加。
Moreover, as water travels through the ground it dissolves and picks up minerals, particularly calcium carbonate.
此外，當水穿過地面時，它會溶解并吸收礦物質，尤其是碳酸鈣。
When it subsequently bubbles to the surface, it deposits these minerals as a type of limestone called travertine,
當它隨后冒泡在地表時，它將這些礦物質沉積為一種叫做石灰華的石灰石，
which has bands in it that reveal by their thickness approximately how long the water which created them was flowing.
石灰華中存在條帶，可以通過它們的厚度顯示出創造它們的水大約流動了多長時間。
The age of a band can be determined by analysis of the radioactive isotopes within it, particularly those of uranium and its decay products.
條帶的年齡可以通過分析其中的放射性同位素來確定，尤其是鈾及其衰變產物。
Dr Rickett therefore predicted that the thicknesses of bands of travertine of the same age from all around the world would be correlated,
因此，里基茨博士預測世界各地年代相同的石灰華條帶的厚度是相關的，
and that those thicknesses would decrease and increase with the coming and going of ice ages.
并且這些厚度會隨著冰河時代的到來和結束而減少或增加。
To test this idea he and his colleagues searched the scientific literature for all the previous studies of travertine they could find.
為了驗證這一觀點，他和他的同事們查閱了所有他們能找到的關于石灰華的科學文獻。
By doing so, as they report in the Journal of Quaternary Science,
正如他們在《Journal of Quaternary Science》中的報告所述，
they discovered the ages of 1,649 deposits of the rock, scattered across every continent except Antarctica.
這么做讓他們發現1649年的巖石沉積物，這些沉積物分布在除南極洲以外的所有大陸上。
To his delight, when Dr Rickett plotted these ages against the thickness of the bands reported,
令他高興的是，當里基茨博士將這些年代與所報告中的條帶厚度進行對比時，
he found that those thicknesses did indeed rise and fall in step.
他發現這些厚度確實是同步上升和下降的。
To his further delight, the dates he deduced for warm and cold periods matched those from the existing way of dating them,
令他更高興的是，他推斷出的溫暖期和寒冷期的年代與用現有年代計算方式所得結果吻合，
which measures the ratio of isotopes of oxygen in fossil teeth—for this ratio is temperature dependent.
通過現有方式測算出了牙齒化石中氧同位素的比例—因為這個比值與溫度有關。
That different dating methods have arrived at the same conclusion in this way
不同的年代測定方法以這種方式得出了相同的結論
is a useful confirmation that palaeoclimatologists' dates for events in the past few hundred thousand years are correct.
這有力地證實了古氣候學家對過去幾十萬年事件的年代測定是正確的。
譯文由可可原創，僅供學習交流使用，未經許可請勿轉載。
