Yellowstone 黄石公园 - West Thumb Geyser Basin

Mimulus Pool

西拇指（West Thumb Geyser Basin）：西姆指间歇泉盆地，位于黄石湖边上，十五万年前因地壳陷落而形成，在热喷泉与湖水结合下，出现了一种烟雾弥漫的奇妙景观：烟雾缭绕处是热泉的蒸气，绿波盈盈处是黄石的湖水，与背景中蓝天白云相互辉映，形成与黄石其他温泉区不同的景观。此处相当于黄石湖的湖湾，许多间歇泉聚集此处，喷水口的颜色多种多样，有的呈透明绿色，有的呈好似水泥色般的暗暗的黑色。许许多多的喷水口呈现一种美丽的幻想。

1870年的沃什伯恩（Washburn）探险队成员发现黄石湖形状类似于“五指展开的手掌”，西侧的湖湾则代表了大姆指。1878年海登（Hayden）调查队用West Arm（西湾）命名这个湖湾，有人也称其为“西湾”。1880-1881年的Norris地图上则被叫做“西湾/西姆指”。二十世纪三十年代，黄石公园的员工试图恢复West Arm这名字，不过西姆指已被普遍接受。这个景区位于位于黄石湖的西侧大拇指的前端，巨型山庄的游客中心的顶端。

西姆指盆地，位于黄石湖边上，十五万年前因地壳陷落而形成，在热喷泉与湖水结合下，出现了一种烟雾弥漫的奇妙景观：烟雾缭绕处是热泉的蒸气，绿波盈盈处是黄石的湖水，与背景中蓝天白云相互辉映，形成与黄石其他温泉区不同的景观。
在西拇指间歇泉盆地，可以见到4种地热形式，分别称为：泥锅（mud pot），温泉（hot spring），间歇泉（geysers）和火山喷气口（fumaroles）。

深渊池 (Abyss Pool)

1869年，黄石地区第一个科学探险队，库克·福尔松·彼得森探险队（Folsom-Cook-Peterson）探险，进入了西姆指间歇泉盆地。福尔松（Folsom）记录了这些字句：“这些温泉和我们以前见过的温泉都不一样。他们分布于两英里长的湖滨，从距离湖水500码到深入湖水几个英尺。这里有几百个不同的温泉，从微型喷泉、小池塘，到直径75英尺的深井。水是淡紫色的，很清澈，我们可以清楚看到水下50-60英尺外的小物体。附近的一小群泥泉引起我们的注意，坑中都是泥，就像很精致的厚厚的油画，泥的颜色从纯白色到黄色，紫色，红色，粉色。下午泥温泉会喷发出高15英尺的泥。

West Thumb Geyser Basin is one of the smallest geyser basins in Yellowstone yet its location along the shore of Yellow-stone Lake ranks it as the most scenic. West Thumb derived its name from the thumb-like projection of Yellowstone Lake and the name was given by the 1870 Washburn Expedition. It was also known as Hot Spring Camp. West Thumb has less geyser activity than other basins. But West Thumb, for its size, has it all-hot springs, pools, mud pots, fumaroles and lake shore geysers.

Fishing Cone has been the most popular feature. Its unusual location along the lake shore and its symmetrical cone were popularized by early stories of "boiled trout." Abyss Pool is also noted for its depth and colors.
The Thumb Paint Pots are constantly changing. In the 1920s and 30s they were very extensive and active. Now they are less active but, depending on moisture, they still build mud cones.

黑色温泉池（Black pool）

Since the mid 1970s, West Thumb has decreased in thermal activity. Some temperatures have cooled in the basin allowing large colonies of algae and cyanobacteria to grow. As a result, large newly-formed microbial mats flourish on the run-off channels and along the edges of pools.

钓鱼锥（Fishing Cone）