Petrified wood (from the Greek root "petro" meaning "rock" or "stone", literally "wood turned into stone") is a type of fossil: it consists of fossil wood where all the organic materials have been replaced with minerals (most often a silicate, such as quartz), while retaining the original structure of the wood.
The petrified trees formed about 150 million years ago in Jurassic. They were covered by silt mud and volcanic ash and this blanket of deposits out of oxygen and slowed the logs’ decay. Gradually silica-bearing ground waters seeped through the logs bit by bit, encased the original wood tissues with deposits. Slowly the process continued the silica crystallized into the quartz and the logs were preserved as a stone mould forms in its place.
It is not wood that makes petrified wood colorful, but the chemistry of the petrifying groundwater. Minerals such as manganese, iron, and copper were in the water/mud during the petrification process. These minerals give petrified wood a variety of color ranges. Quartz crystals are colorless, but when iron is added to the process the crystals become stained with a yellow or red tint.
List of minerals and related color hues:
Copper - green/blue
Cobalt - green/blue
Chromium - green/blue
Manganese - pink
Carbon - black
Iron Oxides - red, brown, yellow
Manganese Oxides - black
Silica - white, grey
The pentrified trees preserve external form and internal structure of trees in detail. Structures such as tree rings and the various tissues are often observed features which can provide evidences for studying plant evolutaion and changes of environment and climate.
Opening Hours: 06:00 – 23:00
Fee for Entrance:
- YMB20/person for adult
- YMB10/person for studend, child and elder
Transportation: Bus no: 57, 218, 220 and 382
To Log this Earthcache, please send the answer of the following questions to owner:
1) What useful purposes has some of the petrified wood been put? (two uses: Please don't copy the answer from Internet.)
2) Estimate the height of the tallest petrified tree on site.
3) (Optional) Post any photo of your GPSr with that petrified tree scenery in the background.
Please don't post the answer into the log.
(P.S. An EarthCache site is a special place that people can visit to learn about a unique geoscience feature or aspect of our Earth. The treasure is the lessons people learn about our plant when they visit the site. Any irrelevant misleading information will be deleted.)