Skip to Content

<

Rapa Nui - Ahu Tongariki

A cache by Mort Send Message to Owner Message this owner
Hidden : 8/4/2015
Difficulty:
1.5 out of 5
Terrain:
2 out of 5

Size: Size: other (other)

Join now to view geocache location details. It's free!

Watch

How Geocaching Works

Please note Use of geocaching.com services is subject to the terms and conditions in our disclaimer.

Geocache Description:





History

Ahu Tongariki


Located in Hanga Nui, on the southeast coast of Easter Island and just 2 kilometers from the Rano Raraku quarry, Ahu Tongariki is the most majestic ceremonial platform on the whole island.
As in all of Polynesia, in Easter Island, worshiping ancestors was a big part of the inhabitants’ spiritual lives. The Rapanui believed that important people's "mana" (spiritual energy) continued existing after their death, and that it had the ability to influence events much after their death, a belief that became tangible in the construction of the moai statues.

This is known as the classic stage, when the Rapa Nui culture reached its maximum splendor raising enormous ceremonial altars or Ahu in which great sculptures where made craved from volcanic rock, which are the most characteristic symbols of Easter Island. The moai period extended between approximately 800 A.D. and 1860, when the conflict between the different bloodlines changed the island’s history. When a tribe’s leader or one of its important members dies, a sculpture was ordered to be created in the quarry of Rano Raraku, which would later be transported to to the respective village, so that it could project its “mana” or supernatural powers over its descendants. The moai statues were always placed looking towards their village and their descendants, not towards the sea, since their objective was not to protect them from outside threats but to extend over them a protective blanket.
Each of the statues is different, some are higher than others, some with fatter bodies and others with more skinnier ones and even in the faces, some have coarse features and others finer features. As the Rapanui became skilled in sculpting and transporting the moai statues, these became bigger and more stylized. The largest statue with a pukao (headdress) is 14 meters tall still can be found in the quarry of Rano Raraku. Once the Moai was set up in its ahu, the eye sockets were sculpted and, in a ceremonious ritual, the eyes made from white coral and red scoria were placed; from this moment on it was considered that the Moai’s mana could project over the tribe. Finally, an enormous red scoria cylinder called pukao was placed on top of its head. The meaning of the pukao is ambiguous, on one hand it is believed to have represented the tribe’s hierarchy and on the other to have symbolized the long hair that the islanders used to wear up in a bun. It’s believed that between the 15th and 18th centuries, Easter Island suffered an overpopulation crisis that caused shortages and conflicts between the 12 island tribes. The obsession of building bigger and bigger moai statues was one of the main causes of deforestation and food scarcity. These problems led to a fall in the belief of the moai’s power and their construction was not only abandoned, but some were even torn down from their ahus.
In 1960 an earthquake that measured 9.5 points on the Richter scale, which struck the Chilean coast of Valdivia, caused a large tsunami in the Pacific Ocean; with waves that reached up to 11 meters high in Easter Island, waves that hit the ahu and dragged the moai up to 100 meters inland, damaging them significantly. The restorations lasted five years, from 1993 to 1996, and were led by Chilean archaeologist Claudio Cristino, who rebuilt the platform based on drawings by British archaeologist, Katherine Routledge. Routledge reached Easter Island in 1914, in the first archaeological expedition made to the island and gathered for 17 months collected much of the information that is now available about the original Rapa Nui culture.The restoration project, which cost over $2 million USD, was possible thanks to funds provided by the Japanese government and the help of a private company from the same country (Tadano), that sent a large crane to the island which helped stand each moaiupright. During the excavations another 17 moais were discovered to be completely destroyed and were used as a base for the current platform, as was the usual thing to do when an ahu was raised in a place where another had once stood.
In recognition of the assistance provided by the Japanese government, in 1982 the moai located at the entrance of Tongariki was sent to Japan, as a loan, to be shown at trade shows in Osaka and Tokyo. Because of this epic journey, the islanders began to call it “the traveling moai”. This moai was also one of the ones Thor Heyerdahl used to test his theories on the transportation of moais.
Another of the wonderful things about Ahu Tongariki is the indescribable spectacle that happens at dawn. Between the 21st of December, the “Summer Solstice”, and the 21st of March, the “Autumn Equinox”, the sun rises behind the Ahu, between its giant stone sculptures, creating an unforgettable sight.


The moai or Easter Island heads or Easter Island statues, represent the most important pieces of Rapa Nui art and they have become its trademark. However, in spite of their abundance, there are around 600 moai distributed throughout the whole island and 397 are in the Rano Raraku quarry, there are still plenty of unanswered questions regarding these stone giants."



Earth Lesson

The Moai


Most of the Easter Island statues were sculpted out of volcanic rock from the Rano Raraku quarry. The eye sockets made from white coral and red scoria. The pukaos or moai headdresses were made from a red volcanic rock (scoria). Rano Raraku is commonly known as the “Moai Factory” There are 397 moai in this area, some half buried, some just abandoned over time. That’s about 45% of all the Moai ever created.
Rano Raraku is a volcanic crater formed of consolidated volcanic ash, or tuff, and located on the lower slopes of Terevaka in the Rapa Nui National Park on Easter Island in Chile.

The volcanic Ash


Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as tephra), including particles larger than 2mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere.

The force of the escaping gas shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometers away.

The volcanic tuff


Tuff (from the Italian tufo) is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is compacted into a solid rock in a process called consolidation. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered tuffaceous. Tuff is a relatively soft rock, so it has been used for construction since ancient times. Since it is common in Italy the Romans used it often for construction. The Rapa Nui people used it to make most of the moai statues in Easter Island. Tuff can be classified as either sedimentary or igneous rocks. They are usually studied in the context of igneous petrology, although they are sometimes described using sedimentological terms.

The Igneous rock


Apart from adventitious material, such as fragments of the older rocks, pieces of trees, etc., the contents of an ash deposit may be described as consisting of more or less crystalline igneous rocks. If the lava within the crater has been at such a temperature that solidification has commenced, crystals are usually present. They may be of considerable size like the grey, rounded leucite crystals found on the sides of Vesuvius. Many of these are very perfect and rich in faces because they grew in a medium that was liquid and not very viscous. Good crystals of augite and olivine are also to be obtained in the ash beds of Vesuvius and of many other volcanoes, ancient and modern. Blocks of these crystalline minerals (anorthite, olivine, augite and hornblende) are common objects in the tuffs of many of the West Indian volcanoes. Where crystals are very abundant the ashes are called "crystal tuffs." In St. Vincent and Martinique in 1902, much of the dust was composed of minute crystals enclosed in thin films of glass because the lava at the moment of eruption had very nearly solidified as a crystalline mass. Some basaltic volcanoes, on the other hand, have ejected great quantities of black glassy scoria, which, after consolidation, weather to a red soft rock known as palagonite; tuffs of this kind occur in Iceland and Sicily. In the Lipari Islands and Hungary there are acid (rhyolitic) tuffs, of pale grey or yellow color, largely composed of lumps and fragments of pumice. Over a large portion of the sea bottom the beds of fine mud contain small, water-worn, rounded pebbles of very spongy volcanic glass; these have been floated from the shore or cast out by submarine volcanoes, and may have travelled for hundreds of miles before sinking; it has been proved by experiment that some kinds of pumice will float on sea-water for more than a year. The deep sea-deposit known as the "red clay" is largely of volcanic origin and might be suitably described as a "submarine tuff-bed."

Tholeiite basalt tuff


Most of the moais in Easter Island are carved out of tholeiite basalt tuff.The tholeiitic magma series, named after the German municipality of Tholey, is one of two main magma series in igneous rocks, the other magma series being the calc-alkaline. A magma series is a series of compositions that describes the evolution of a mafic magma, which is high in magnesium and iron and produces basalt or gabbro. Rocks in the tholeiitic magma series are classified as subalkaline (they contain less sodium than some other basalts) and are distinguished from rocks in the calc-alkaline magma series by the redox state of the magma they crystallized from (tholeiitic magmas are reduced; calc-alkaline magmas are oxidized). When the parent magmas of basalts crystallize, they preferentially crystallize the more magnesium-rich and iron-poor forms of the silicate minerals olivine and pyroxene, causing the iron content of tholeiitic magmas to increase as the melt is depleted of iron-poor crystals. However, a calc-alkaline magma is oxidized enough to precipitate significant amounts of the iron oxide magnetite, causing the iron content of the magma to remain more steady as it cools than with a tholeiitic magma. On other hand as we already mentioned the pukaos were made from red volcanic rock which name is scoria.

The Scoria


The pukaos(moai headdresses) were made from red volcanic rock(scoria). Puna Pau Volcano's crater was the quarry from were the scoria where taken.The Scoria is a dark-colored igneous rock with abundant round bubble-like cavities known as vesicles. It ranges in color from black or dark gray to deep reddish brown. Scoria usually has a composition similar to basalt, but it can also have a composition similar to andesite. Many people believe that small pieces of scoria look like the ash produced in a coal furnace. That has resulted in particles of scoria being called "cinders" and the small volcanoes that erupt scoria to be called "cinder cones." Scoria forms when magma containing abundant dissolved gas flows from a volcano or is blown out during an eruption. As the molten rock emerges from the Earth, the pressure upon it is reduced and the dissolved gas starts to escape in the form of bubbles. If the molten rock solidifies before the gas has escaped, the bubbles become small rounded or elongated cavities in the rock. This dark-colored igneous rock with the trapped bubbles is known as scoria. When some volcanoes erupt, a rush of gas blows out of the vent. This gas was once dissolved in the magma below. The gas often blows out small bodies of magma that solidify as they fly through the air. This action can produce a ground cover of scoria all around the volcanic vent, with the heaviest deposits on the downwind side. Small particles of scoria that litter the landscape around the volcano are known as "lapilli" if they are between 2 millimeters and 64 millimeters in size. Larger particles are known as "blocks."



Logging This Earthcache

1. Walk around the platform and examine the "statues" serious-looking faces. All 15 figures stand side by side and face the sunset during summer solstice. According to the geolist above could please describe the material from which the statues were build ?

2. During your examination you will see that the second moai from the right has a pukao on its head. Could you please describe the material from which that headdress was build ?. Do you know from which quarry is coming that material ?

3. How to volcanic ash is formed ?

4. How long is the ceremonial platform in m ?

5. Optional, a photo of you and/or your GPSr that was taken at the posted co-ordinates would be appreciated..


Note: Please send me your answers within 4 days of posting your found log. If there are more then one cacher in your party, include the names in your group. Only one person needs to send me the group answers. Go ahead and submit your log as I will not necessarily respond to your email. Found logs posted without proof you visited the site will be deleted. Please email me to my profile (no message center please) your findings.

Happy Earthcaching!









Flag Counter

Additional Hints (No hints available.)



 

Find...

67 Logged Visits

Found it 65     Write note 1     Publish Listing 1     

View Logbook | View the Image Gallery of 54 images

**Warning! Spoilers may be included in the descriptions or links.

Current Time:
Last Updated:
Rendered From:Unknown
Coordinates are in the WGS84 datum

Return to the Top of the Page

Reviewer notes

Use this space to describe your geocache location, container, and how it's hidden to your reviewer. If you've made changes, tell the reviewer what changes you made. The more they know, the easier it is for them to publish your geocache. This note will not be visible to the public when your geocache is published.