向南美出發 Day 17
Credit: Earth Magazine.org
Easter Island is a volcanic island located a few hundred kilometers east of the planet’s fastest oceanic spreading center. Credit: both: K. Cantner, AGI.
Hot Line or Hot Spot?
Easter Island, which at 164 square kilometers is slightly smaller than the District of Columbia, is an amalgamation of three volcanoes that erupted between about 780,000 and 110,000 years ago. The island lies near the western end of a 2,500-kilometer-long chain of underwater volcanoes called the Easter Seamount Chain that resembles the classic Hawaiian hot spot track, which is thought to have formed as the Pacific Plate slowly drifted across a persistent upwelling of hot material from deep within the mantle. Yet, unlike the Hawaiian Islands, whose ages steadily rise with increasing distance from the active volcanoes, the Easter Seamount Chain has no clear age progression, with very young volcanoes spanning more than 500 kilometers of its length.
Easter Island is just a few hundred kilometers east of the southern East Pacific Rise spreading center, so it sits on young oceanic crust that’s just 2 million to 4 million years old. But the island’s volcanoes are younger still, so the island couldn’t have formed simply from mid-ocean ridge volcanism. Researchers have proposed many alternative hypotheses to explain the seamount chain, including that it’s a manifestation of a new plate boundary; that it sits atop a “leaky” transform fault; or that the chain, from Easter Island to Sala y Gómez Island 400 kilometers to the east, results from volcanism from a long, thin mantle “hot line” instead of a typical hot spot.
YOUTUBER:
訪問復活節島旅遊指南(德島帕斯誇 - 拉帕努伊)
下了飛機見到屋主接機,她帶我們行一次市區,介紹不同的設施給我們。
之後,我們就在市中心食飯行逛。這裡的溫度舒爽,非常清閒。但這地的物價很貴,有香港中環的指數。因為這裡環海,但受冷流和地形影響,所以很少魚獲。這邊以牧場為主,有馬、牛。
DAY 1 21/7 HONG KONG/DALLAS (US)
DAY 2 22/7 DALLAS (US)/LIMA(PERU)/CUSCO(LIMA)
DAY 3 23/7 Cusco/Peru
DAY 4 24/7 Cusco/Moray, Salinas de Maras/Peru
DAY 5 25/7 Machu Picchu/Peru
DAY 6 26/7 Rainbow mountain
DAY 7 27/7 Cusco/Peru-->Puno/Peru
DAY 8 28/7 Puno/Peru
DAY 9 29/7 Puno/PeruàLa Paz/Bolivia
DAY 10 30/7 La Paz/Bolivia
DAY 11 31/7 Uyuni/Bolivia
DAY 12 01/8 Uyuni/Bolivia
DAY 13 02/8 Uyuni/Bolivia
DAY 14 03/8 Uyuni/BoliviaàPedro de Atacama/Chile
DAY 15 04/8 Pedro de Atacama -> Santiago/Chile
DAY 16 05/8 Santiago-->Easter Island/Chile
DAY 17 06/8 Easter Island/Chile
DAY 18 07/8 Easter Island/Chile
DAY 19 08/8 Easter Island/Chile
DAY 20 09/8 Easter IslandàSantiago/Chile
DAY 21 10/8 Santiago
DAY 22 11/8 SANTIAGO (CHILE)
DAY 2312/8 DALLAS (US)
DAY 2413/8 HONG KONG
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