Slow Heart Beat (Bradycardia) An abnormally slow sinus heart rate is called the âsick sinus syndromeâ and, if severe, results in symptoms of fatigue. In some such cases a permanent pacemaker is needed to be implanted to generate a normal heart rate. Many people with sick sinus syndrome also develop atrial fibrillation.
Petrified wood (from the Greek root petro meaning rock or stone; literally wood turned into stone) is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization.lements such as manganese, iron, and copper in the water/mud during the petrification process give petrified wood a variety of color ranges. Pure quartz crystals are colorless, but when contaminants are added to the process the crystals take on a yellow, red, or other tint.
Introduction. Petrified, or silicified, wood is a type of fossil that has been found all over the world in Argentina, Denmark, Mexico, China, Japan, New Zealand, Indonesia, and much of the southwestern United States.ne of the largest deposits of petrified wood is found in the Petrified Forest National Park in Arizona. The land that is now much of Petrified Forest National Park was set aside in 1906 by president Theodore Roosevelt as the nation's second national monument, which Congress then made a national park in 1962 (Uhler).