Environmental tale told at Petrified Forest
Liz Price
Sunday, October 28, 2007
TREES turned to stone, logs frozen in time, a painted desert and badlands.
This is the Petrified Forest, an area of petrified wood, the remains of an ancient forest which lies scattered across north-eastern Arizona in the US. A remnant from eons ago, part of it now forms the Petrified Forest National Park.
It is a land of contrasts. There are fossils of tall trees, ferns, large reptiles, small sharks and dinosaurs. The desert which forms today's landscape was once under water 225 million years ago.
It all began as a forest in which lived crocodile-like reptiles, fish-eating amphibians and small dinosaurs. The giant trees fell and were washed away into the floodplain to the north. They were then covered by silt, mud and volcanic ash. This blanket of deposits cut off the oxygen supply and slowed the logs' decay. Gradually, silica bearing ground waters seeped through the logs, slowly encasing the original wood tissue with silica deposits. This silica crystallised into quartz, and the logs were preserved as petrified wood.
Later the area sank and then flooded. Eventually the area was lifted above sea level and during this process the resulting stresses cracked the giant logs. The elements such as wind and water eroded the accumulated sediments revealing the petrified logs as seen today. But as well as the logs, fossilised animal and plant remains were exposed.
And the process continues. It is known that in some places up to 90m of material lies buried.
And all these remains tell a story, showing how the environment has changed over the past 225 million years.
It has been proved that man settled in this area about 2,000 years ago. There are remains of human culture potsherds, rubble, rock paintings, which indicate a nomadic society which changed to a settled agricultural one. The Puerco Ruins were occupied twice, from 1100 to 1200, and again from 1300 to 1400AC, but after that no signs of human habitation have been found.
The area was rediscovered in the mid 1800's by US Army mappers and soon attracted sightseers. Many took souvenirs of wood with them but luckily the locals realised that the supplies of petrified wood were not endless, and set up the area as a National Monument in 1906. The National Park was established in 1962.
Today there are strict laws to protect the Park and there are heavy fines for anyone caught removing any of the wood. However, it is rumoured that the removal of wood from the Park brings bad luck, and every week the rangers receive packets of wood posted back to the Park from people who have taken it, often many years ago, but who now feel guilty. Accompanying letters reveal how much bad luck the wood has brought upon the people.
Petrified wood can be bought from commercial dealers who have collected it from outside the Park boundaries. Small pieces are sold in the natural state or else polished, shaped as bookends, jewellery, animals etc. Minerals and impurities give the wood bright colours and interesting patterns which are quite beautiful when polished.
The Park has a 43km scenic drive. Entering from the north end one firstly sees the Painted Desert Visitors Centre. The Painted Desert is an area of desert formed from coloured rocks shades of red, cream, purple, brown and grey. There are many lay-bys and it is tempting to stop and take many photos as the area is so photogenic. There are also places to hike and camp in two designated wilderness areas.
The Painted Desert Inn was built in the 1920s and is now a museum. From here the road then crosses the main highway and enters the Petrified Forest area, where one can see the Puerco Indian ruins and the petroglyphs or rock drawings.
The Tepees are interesting, they are badlands erosional formations, huge pyramidal or tepee shaped rocks looking like a moonscape. These badlands are formed from sandstone and clays, and are coloured by iron, manganese and other minerals.
Walking trails loop around various points of interest. There are a few separate areas of forest, such as Jasper Forest, Crystal Forest, Long Logs and Blue Mesa. Old Faithful is one of the largest logs, found in an area appropriately named Giant Logs. It is almost 11m long and weighs about 40,000kg.
The Agate Bridge is a long log spanning a small ravine and although still in its natural setting it has been given a supporting base to prevent it from collapsing.
Describing the Petrified Forest on paper does not do it justice it has to be seen to be appreciated.
The Brunei Times
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Source URL:
http://www.bt.com.bn/en/en/travel/2007/10/28/environmental_tale_told_at_petrified_forest
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