夏玛尔的七色土：彩虹不只天上有

The impressive "Seven Colored Earths of Chamarel" is named for the strange natural colors of a fairly small area （roughly 7500 square meters） covered in sand dunes2） made of clay minerals that formed from basaltic3） lava in South Western Mauritius， an island in the Indian Ocean. The seven different colors are red， yellow， green， blue， violet4）， purple and brown， and they are capable of forming truly remarkable patterns. This is due to the fact that the different colors， being comprised of different clay minerals， naturally settle into layers， or bands， each of a different color， with different colors being more or less distinct as light hits them from different angles at different times of the day.

在印度洋中坐落着一个名为毛里求斯的岛国，其西南部有一块很小的地区（约7500平方米），这里布满了由玄武质岩浆形成的粘土矿物所构成的一座座沙丘。这些沙丘自身的颜色非常奇特，景色非凡，“夏玛尔的七色土”便由此得名。这七种不同的颜色分别为红色、黄色、绿色、蓝色、紫罗兰色、紫色和棕色，它们可以组成无比壮观的图案。这是因为这些不同的颜色（由不同的粘土矿物所组成）天然地分层或呈带状分布，彼此颜色各异，而且在一天之中的不同时段，当阳光从不同的角度照到不同的颜色上时，就会有某种颜色或多或少地突显出来。

A Strange Geographic Anomaly5）

奇特地貌

Although Geological Science has explained the different colors of the sand as being the result of molten lava cooling at different rates due to inconsistent temperatures and forming oxides6） of various metals including iron and aluminium7）， they have not fully explained its tendency to settle into layers. And no place on earth of a similar geography is known. While places like Australia and Papua New Guinea have similar terrain8）， the same seven colors are not present. Some organizations have thought about excavating at the site to determine the cause of this phenomenon， but have elected not to risk9） destroying the formation. If you wish to have some of the sand for your own， however， some local gift shops in Chamarel sell small vials10） of it.

Luckily， the dunes do not seem to be facing complications due to erosion， despite the heavy rains that often drench11） the island， which is another mystery. The rains do， however， leave their mark as they travel over the dunes， leaving patterns of criss-crossing12） channels13） as they go， resulting in web-like patterns changing with each storm and making the dunes even more beautiful.

地质学已对这些沙为什么会呈现出不同的颜色做出了解释（由于温度不恒定，导致熔岩以不同的速度冷却，形成了含有铁、铝等各种各样金属的氧化物，从而产生了不同的颜色），可是却没有解释清楚为什么这些颜色总会分层，而且也并没听说地球上有其他地方具有相似的地貌。尽管澳大利亚、巴布亚新几内亚等地也有类似的地貌，但却没有出现与此相同的七色景观。一些机构曾考虑过进行就地挖掘，以查明该现象的成因，但还是决定不去冒险破坏这一景观。不过，如果你想自己收藏一点彩沙的话，夏玛尔当地的一些礼品店出售小瓶的七色彩沙。

幸运的是，尽管岛上时常会大雨倾盆，但这些沙丘似乎并没有遇到雨水侵蚀引发的各种问题，这又是一个谜团。然而，雨水流经沙丘时的确会留下痕迹，它们流经之处都会留下纵横交错的沟壑组成的各种图案，而且这些错综复杂的图案还会随每场暴雨变化，使沙丘变得愈发美丽。

Some time between the dunes&apos； discovery and there having been turned into a privately owned tourist attraction sometime in the 1960&apos；s， visitors were not allowed on the dunes due to their tendency to take the odd and beautiful sand home with them， though a small network of trails leads around them with large elevated observation decks at intervals. While the trails allow visitors to get a close look at the dunes， and associate themselves with some of the region&apos；s wildlife， including tortoises， the observation decks allow more impressive views of larger expanses of the park.

The dunes， which are entirely devoid14） of vegetation， mysteriously arise out of a patch of dense forest. Whether some strange anomaly prevents the growth of vegetation or whether owners remove any by hand in order to preserve the park&apos；s beauty is up to speculation. But their rising out of the forest has been guessed at. Some have suggested that the area was once cleared for the production of sugarcane， for which the island was most used in the 17th century， but rain washed away the topsoil， revealing the dunes and leaving them unfit to sustain a crop. Most of the island&apos；s natural wildlife and vegetation was eradicated during this period of British colonization， making the island&apos；s involvement in tourism in 2014 an important step towards preserving what is left of the island&apos；s natural history15）. This time may have permanently changed the geography of the island， but it has also made the area more interesting.

从沙丘被发现到这里在20世纪60年代某个时候变为一处私营旅游景点之间的一段时间，游客是不可以踏上沙丘的，因为他们总爱带点这种奇特又好看的沙子回家。不过沙丘四周纵横交错的步道可以指引游客四处转悠，步道上每隔一段距离还建有高高架起的大观景台。步道让游客能近距离地观赏沙丘，还能亲近该地区的一些野生动物，比如乌龟；而观景台则让游客可以欣赏到沙丘公园视野更为广阔、更壮观的景色。

这些沙丘完全寸草不生，却不可思议地出现在一片茂密的森林之中。是某种奇特的反常现象阻碍了植被的生长？还是所有者为保全这个公园的美景而人工清除了长出来的任何植被？这就只能去推测了。不过，人们一直在猜测森林里为什么会冒出这么一片沙丘。有人认为，这个地区曾被开垦出来种植甘蔗（这是毛里求斯岛在17世纪最主要的用途），但雨水冲走了表土，露出了沙丘，从而使其不适宜作物生长。岛上大部分的野生动植物在英国殖民统治的这一时期都被消灭殆尽，这使得毛里求斯2014年对旅游业进行的投入成为保存该岛现有动植物的重要举措。这一时期或许永久地改变了该岛的地貌，不过它也使这一地区变得更有吸引力。