UPPER GEYSER BASIN and WEST THUMB GEYSER BASIN

Located south of Norris Geyser basin,Upper Geyser basin  has  around  410 geysers. The predictable
geysers found here  includes Old Faithful, Castle geyser, Grand Geyser, Daisy geyser and Riverside
Geyser. The Upper Geyser Basin is Yellowstone’s largest geyser basin and is positioned in between
the Old Faithful area and  Biscuit Basin road . It is home to the world’s largest single
concentration of hot springs. The whole geyser basin occupies only one square mile. 

Several geyser group can be found here like Sawmill group,  Giant group, Myriad group, Grotto
group, Morning glory group, Biscuit basin and  Black sand basin. The most famous geysers here is
the Old  faithful geyser. Less popular ones  include  Giantess geyser, Doublet pool, Solitary Geyser,
 Observation point, Plume geyser, Beehive geyser, Heartspring, Lion group of geysers, Sawmill
 geyser, Grand geyser, Crested Pool and Castle geyser. North section of Upper geyser basin consist
of Beauty pool, Chromatic spring, Giant geyser,Comet geyser, Splendid geyser, Punch Bowl spring,
 Daisy geyser, Grotto geyser, Riverside  geyser, Fan and Mortar geyser, Morning glory pool and
Biscuit basin - Sapphire pool

Old Faithful is the most famous geyser at Yellowstone National Park. This is a cone geyser  which
erupts water to a height of 106 to 185 ft at an interval of 90 mts with a margin of error of 10 mts.

 It is not connected to any of the thermal features in Upper geyser basin . It was the first geyser to be

 named in Yellowstone park and was  named in 1870 by the Washburn expedition team. The

 team explored the region of northwestern Wyoming  that two years later became Yellowstone 

National park. Due to its reliability it got the name Old Faithful which was once called as 

“Eternity’s Timepiece” because of the regularity of its eruptions. 

Around 3700  (1.5 mts ) to 8400  ( 4.5 mts) gallons of hot water are expelled during eruption  which
 depend on the duration of ejection . Split cone geyser and tea pot geyser sit adjacent to Old faithful.
In the early days  of the park, Old Faithful was once degraded and often used as a laundry.  Garments
 placed in the  crater quiescence are ejected thoroughly washed when eruptions take place. Linen and
 cotton fabrics  were undamaged while woolen cloths torn to shreds.

Constructed in 1903–1904, and situated next to Old faithful  geyser is the Old Faithful Inn, a historic

landmark. It  is constructed largely using locally obtained materials including lodge pole pine and

rhyolite stone, This  multi-story log lobby is flanked by long frame wings containing guest rooms.

This  is the largest log hotel in the world and an example of  "Golden Age" of rustic  resort

  architecture, a style which is also known as National Park Service rustic. It is unique in that

 it is one of the few log hotels still standing in the United States. 

West Thumb Geyser Basin is situated between Old faithful and Fishing Village.West Thumb is a 

originally a caldera within a caldera. It derived its name from the thumb-like projection of

 Yellowstone Lake and the name was given by the 1870 Washburn expedition team. Fishing cone

 and Abyss pool are the most popular features here.

 Lake-shore group, Lower group and  Potts Hot spring are the major groups of geysers at West 

thumb. Blowhole Spring , Lone pine geyser, Occasional geyser, Overhanging geyser,Abyss pool, 

Beach  geyser,Big cone, Black pool, Blue funnel spring, Fishing cone,Hill side, King geyser, Lake

 shore  geyser, Ledge spring, Percolating spring, Perforated pool,Roadside steamer, Surging spring, 

Twin  geyser, Mercurial geyser, Resurgent geyser are a few of the named features at West Thumb geyser basin.

 Overlooking Yellowstone river, West Thumb geyser basin has around 84 geysers. There are two 

loops at West Thumb geyser basin. The Inner Loop is 1/4 mile and fully accessible while the Outer

 Loop is 1/2 mile and has steep grades on both sides. Mimulus Pool and Painted pots are seen just at

 the entry. Mimulus Pool seen here has a bluish green color with a smooth texture appearance.

Perforated pool got its name from the high number of vents visible on the bottom of the pool. Hot 

pools in many shades of blue are sprinkled throughout West Thumb Geyser Basin. Many of the areas

 here are closed to public entry. It is believed that a massive explosion has created this basin.At the 

Fisherman's Geyser, now fairly covered by the lake, was once used by Fishermen to cook their fish.

 Absaroka range, early known as Yellowstone range, border the West thumb basin. It is  a sub range

 of Rocky Mountain and forms the core of the Yellowstone region of the Central Rockies. Stretching 

 across Montana- Wyoming border for about 240 km, it constitute the eastern boundary of 

Yellowstone National Park along with Paradise Valley Mountain and the western side of the Bighorn Basin.

History says that around 150,000 years ago a volcanic explosion formed this small caldera, now

 known as West Thumb Geyser basin.Underwater hot springs and geysers keep some areas of West

 Thumb free of snow in winter. With Yellowstone Lake and the Absaroka Range of  mountains 

beyond, West Thumb’s hot pools rest in a tranquil and unique spot..

Along the northwest corner of Yellowstone Lake there are three park villages (Bridge Bay, Lake 

Village, and Fishing Bridge)  which offer a variety of services and activities. It has hotel, visitor 

center, campground , gas station and lodge. Fishing bridge is considered as the northern boundary of

 Yellowstone river. Fishing Bridge was named after the original bridge in 1902,when it was a

popular fishing spot in the park. Tons of cutthroat trout fishes flocks through the water, which can be

watched  from the bridge railings.

Yellowstone National Park is one of the most amazing national park in the world.  From the first 

encounter by John Colter (1804-1806), a member of Lewis-Clark expedition team, the park now 

witness around 3,000,000 visitos per year. All resources and archaeological remains found here are

protected  by federal law. While protecting the natural, historic and cultural resources here, safety of

 the visitors is equally important. Always follow the rules and regulations and seek the aid of rangers 

(known as Spread eagle men ) when needed. Keep this priceless jewel of nature remain unimpaired

 for future generations.

MIDWAY GEYSER BASIN with GRAND PRISMATIC SPRING

Midway geyser basin seen alongside the Firehole river, is situated between the Upper and Lower
geysers basin . It is also home to one of the two largest geysers of Yellowstone National Park.
 In early days it  was  known as "Hell's Half Acre". The major geysers groups found  here 

are Excelsior geyser group,  Flood group and Rabbit creek group .

A hot spring is the result of geothermally heated ground water coming out through cracks in earth's

 surface. Unlike geysers which have obstruction resulting in their eruption, hot springs is 

unobstructed. It creates a cycle of hot water rising, cooling and falling . Flood Group and  Rabbit 

Creek group in Midway geyser basin  has no trails leading to it . This geyser basin have many
unnamed features . Flood group  consist of Flood geyser, circle pool  and West flood geyser.
  Egeria Springs and silent pool are the prominent ones in rabbit creek group.

Firehole River is a part of Missouri river system and is one of the two major tributaries of Madison 

river. It was named as firehole by early tappers due to steam rising from the water . It contain three of
Yellowstone's major waterfalls like Kepler cascades, Firehole falls and the Cascades of Firehole in Firehole canyon. 

The river  is surrounded by geothermal features which empty water into it resulting in high 

temperature of the river water. The river also contain dissolved chemicals and minerals from the
geothermal  features of Yellowstone. It is a fishing mecca and is famous for fly fishing. Brown trout
and Rainbow trout are mostly seen in this temperate water.

 In 1880's, Excelsior geyser was considered as one of  the largest geyser in the world . Due to the
violent eruptions, the internal plumbing system got damaged resulting in gas leakage and loss of
thermal energy. It is a productive thermal spring these days with a discharge of  around 4000 to 4500
 gallons of water per minute at a temperature of 199 degree Fahrenheit flowing directly into Firehole river.

 Last major eruption of Excelsior geyser was in 1985, reaching to a height of 300 ft. But due to
powerful eruptions its internal plumbing system got damaged and now it is seen only as a productive
 hot spring . Excelsior Group contain  Excelsior Geyser, Grand Prismatic Spring and Indigo
Spring. Numerous vents boil and churn the water within the crater and cover it in a dense layer of steam .

In June and July, purple fringed gentians are common here and bloom on the barren ground
surrounding this pool. This is also known as Rocky Mountain Fringed Gentian and is the official
flower of Yellowstone National Park. This  park flower  is also named  as Thermalis after the hotspring.

The Grand prismatic spring was first officially described by Ferdinand Heyden in 1871 , the leader of

 first federally funded exploration team of Yellowstone . According to him "Nothing ever conceived 

by human are could equal the peculiar vividness and delicacy of color of these remarkable prismatic

 springs. Life becomes a privilege and a blessing after one has seen and thoroughly felt these 

incomparable types of nature's cunning skill." . The most stunning view in the entire Yellowstone
National park is the Grand Prismatic Spring.

Grand prismatic spring has a diameter of 370 ft and depth of 121 ft . It discharges 2100 liters of hot 

water per minute. This is the largest hot spring in United Nation and third largest in the world.

 Frying Pan lake in  Zealand is the largest hot spring in the world followed by  Boiling lake in
Dominica.  Grand prismatic spring is named for its striking colors which match the rainbow 

dispersion of white light by an optical prism . 

The rainbow colors are the result of single celled pigmented microbial called Archae in the microbial

 mats, which grow around the mineral rich water. The amount of color depend on the chlorophyll to

 carotenoids and also based on temperature which favors one archae over another. During summer the

 prominent colors are orange and red while in winter they are dark green. The center of pool is blue 

and sterile due to extreme heat.

Opal pool at Midway geyser basin  is a fountain type geyser though behave as active hot spring.
Eruptions reach at a height of 30 ft to 70 ft. It is the largest active geyser at Midway geyser basin .
 It completely drained out in 2005 and  refilled as a vivid green pool in 2008.

Turquoise pool  is a pool with  milky white bottom and gem like blue colored water. The dissolved 

minerals add an opalescent iridescence. It maintains an underground connection with Excelsior 

geyser.It is evident when Excelsior is active, the water in Turquoise pool get lowered and took 

nearly an year to recover.

Many geysers here are ignored due to absence of trail system and limited visibility from the

road. The present  half mile boardwalk trail runs part way around the Grand Prismatic spring and 

past two much smaller pools (Opal and Turquoise) and to the adjacent crater of Excelsior Geyser.

In thermal areas the ground may be only a thin crust above  boiling hot spring or scalding mud. There

 is no way to guess a safe path as new hazards can bubble  up overnight. Hence it is always advised to

 stay on board walk

Camera : Canon t5

LOWER GEYSER BASIN , YELLOWSTONE NATIONAL PARK

Geyser is a geological feature in which a spring is characterized by intermittent discharge of water
 ejected turbulently, accompanied by steam. Geysers are usually found near active volcanic areas
where there is proximity of magma. Intense heat, water and plumbing system are the three ingredients
for a geyser. Geysers occur when water passes through fissures and cracks on earth surface and
 contact with the hot rocks at a depth of 6600 ft and get boiled. Boiling of the pressurized water result
 in the geyser effect of hot water and steam ejecting out through the vent on geyser surface . 

Geysers can be classified as Cone geyser and Fountain geyser. Cone geyser erupts from mound of
volcanic rock (siliceous sinter or geyserite ) and erupt in steady jets. While fountain geyser erupts
from  pools of water in a series of intense or violent burst. Geysers only  persist  in places where
volcanic rhyolite rock dissolves in hot water and form mineral deposit (siliceous sinter or geyserite)
inside the  slender  plumbing system of the vent. The minerals thickens the inner walls of the cracks. The specific colors of geysers can be attributed to micro living organisms which thrive in extreme weather conditions.

Geysers exist only in few places in the world and Yellowstone has the highest concentration of it.
  Valley of Geysers in Russia have the second largest geyser concentration in the world and it is the
only place in Eurasia having geyser. El tatio Chile, Taupo Volcanic zone Newzealand  and Iceland
are the other places in the world where one can see geysers. Geysers found in solar  system are
known as Cyrogeysers and the ejections from such geysers are mainly nitrogen and carbon dioxide.

Lower Geyser basin is the largest geyser area in Yellowstone. It extend over 12 sq miles and is 

located north of upper and midway geyser basin on the grand loop road . Lower basin posses a large
 variety of  thermal features like mud pots, geysers, pools, springs and fumaroles. The .5 mile
 Fountain Paint pot trail gets visitors up close to attractions like Great Fountain  geyser, Silex spring,
 Celestine Spring, Fountain Paint pot, Leather Pool Morning Geyser, Jet Geyser, Clepsydra Geyser  and Red Sprouter.

Thermal features of Lower Geyser Basin are scattered and fall under several groups like Fountain
group, Kaleidoscope group, Fire hole Lake group, White dome group, White creek group, Black
warrior  group, Sprinkler group, thud group , Imperial Group and so on. All geysers seen here
belongs  to any of these group. 

Great fountain geyser  is the only predicted geyser in the lower basin. Located in the Firehole lake
area of Lower geyser basin, Great Fountain Geyser erupts every 9 -15 hrs up to a height of 23 to 67
mts. Sometimes it also exhibit  a wild phase behavior pattern which make it sometimes unpredictable.

Silex Spring is a blue pool rimmed with white silica. Silex is a Latin word meaning silica , a major 

component of rhyolite, the volcanic rock found abundantly  at Yellowstone. The water here is too hot

 which is evident by the blue color of the pool . Thermophiles which survive this hot water is seen in 

yellow color on the rippling runoff water surrounding the pool. The orange color seen here  is due to 

the presence of these heat loving bacteria.

A deep blue color pool called celestine pool can be seen here. Beside it is another pool called Leather
pool, that  resemble  leather due to the thick mats of brown thermophile. The pool lost its brown color
after the1959 earthquake that created  high temperature and killed all its bacteria. 

Morning Geyser is a seldom active but one of  the largest geyser in the Fountain area and one of the 

largest geysers in the world. Its last period of activity longed for one week in 1994. Twig Geyser is

 another major geyser and first of the regularly erupting geysers on this trail. Jet Geyser  plays in the

 hours leading up to an eruption from Fountain Geyser while Spasm is a small geyser right next to

 the boardwalk. Sizzler is a small geyser and erupted  from a cracks in the sinter. More recently it has

 started forming a crater

Bacteria Mats is another interesting feature at Lower Basin. Here a vast area is seen in thick colors
 which means the presence of thermophiles. The green , brown orange colors are due to the activity
of cynobacteria which can survive in 167 degree F.  They become yellow or green at hot temperature
 but become orange, rust or brown colored when water cools. Colors can also vary due to stress such
 as  intense sunlight of midsummer. 

Fountain Paint Pot is a type of thermal feature called a mud pot or mud volcano . It  has the odor of
 rotten eggs due to the presence of hydrogen sulfide gas. The acid and microorganisms dissolve the
 rocks  into clay and mud. Mud pots usually appear in white or grey but also appear in red or pink
  due to the presence of iron oxides and minerals. Mud pot is a natural double boiler. In early summer
they are thin and watery and become thick by late summers. The mud is composed of clay minerals
 and fine particles of silica. Rocks found here is rhyolite composed primarily of quartz and feldspar.
Acid in the steam and water breakdown feldspar into a clay mineral called Kaolinite .

Red Sproutter is another attraction at Yellowstone. The 1959 Hebgen lake earthquake, which was one

 of the strongest and deadliest earthquake in history, created many new geysers and cracks in
Yellowstone  National Park  including the Red Sproutter. It exhibit the behavior of geyser, fumarole,
 hot spring and mud pot. During early summer its pool splashes red colored muddy water and in late
 summer and  fall it changes into a hissing fumarole.  

Lodge pole pine is the common variety of trees find in Yellowstone. A group of Lodge pole pine 

trees seen at Lower basin are pioneers that did not survive.  Silica presence in the basin  has 

penetrated the trees and hardened their base which slowed their decomposition.

There are many dormant geysers in Lower geyser basin which take our attention only when it is
active.  Jelly Geyser erupts in a range of 10 mts to more than an hour and last for less than a
minute. Clepsydra ,meaning water clock in Greek,  is another geyser which erupts to a height of 45 ft.
 It was a predictable geyser which erupted every three minutes before the earthquake of 1959. Lower
Geyser Basin is one such area  where one can witness all kinds of thermal features in one area
 including active geyser, dormant geyser, pools, mud pots and fumaroles.

Camera : Canon t5