StoneForest

and beautiful land. Logs turned to stone are strewn like giant matchsticks over land where successive climactic changes have drastically altered the scene many times. [Music] Wood grain transformed into semi-precious stone. [Music] The riddle of ancient man. A man we know only from the painstaking scratches he made in solid rock. The Petrified Forest National Park in northeastern Arizona is a big country with sky to match. [Music] A land where moods change daily and sometimes hourly. [Music] Where broad vistas cause urban man to gasp and details delight those less hurried enough to look. A barren wasted void. Hardly [Music] life cycles cadenced by the passing sun abound. As everywhere in nature, there is the fierce competitive fight for survival. From the smallest to the largest, [Music] a continuence of life in a desert seemingly devoid of life. [Music] The petrified forest as it appears today is the product of much geologic change. Changes which are only partially understood by scientists. painstakingly piecing together a complicated story. A century ago is a long time to man. A thousand years ago is an eternity. A 100,000 years ago boggles the imagination. And a million years ago is simply an abstract. Yet, the petrified forest story goes back further than that. 200 times further back, in fact. Let your mind's eye dissolve the present scene into a low-lying plane. A very young primeval earth where distant volcanoes belched and rumbled. [Music] Primitive exotic amphibians and reptiles crawled and slithered about. Perhaps an early dinosaur or two were struggling for the survival that would make his kind the dominant life form some 50 million years hence. Lungfish, clams, and snails groped in the muddy ponds. There were seasonal floods above the marshlands and water courses. High above the undergrowth rose stately cone bearing trees. Condense, simplify, and even visualize the petrified forest story. Do it not for academic accuracy, but for easy understanding. accept the scientist's word for those things he can prove with reasonable certainty and join with him in speculating about the perplexing mysteries which remain. The dank waterlogged land of 180 to 200 million years ago hosts life cycles in which trees live and ultimately die. Rotting logs return nourishment to the soil, but some, only a very few, crash into stream beds and river bottoms. Sometimes they remain close to where the dead tree fell. [Music] With others, the dead logs tumble and batter their way downstream until log jams are formed. [Music] When conditions were just right, mud, sand, and volcanic ash quickly covered some of the fallen trees and trapped by a mantle which excluded oxygen and slowed the rate of decay. These relatively few logs rested as silicaden waters flowed through the ground. Debris buried the trees deeper and deeper, compacting the mass into layers hundreds of feet thick, a million to one. Those are the odds given by scientists for petrification. Yet, the rare event took place hundreds, perhaps thousands of times here in northeastern Arizona. Volcanic ash is often rich in silica in the form of unstable glass. Under just the right conditions of temperature and alkalinity, the silica dissolves in water. The solution percolated through the buried tree, filled the cell walls and hollow spaces in the wood. Why the silica crystallized into quartz, replacing the wood cell by cell is an unanswered question. Perhaps the logs were highly acidic and the silica came out of solution. At any rate, tiny crystals less than 1/200th of a millimeter in size were formed. [Music] Slowly, ever so slowly, the rockh hard crystals formed exact replicas of the logs they replaced. Pure silica appears almost colorless, white, gray, or tan. [Music] Traces of other minerals such as iron and manganese oxides, copper and chromium filtered into the solution where combined with the silica quartz they produced a vivid array of colors and patterns. [Music] [Music] [Music] It is an oversimplification to end the petrified forest story. At this point, the logs turned to stone lay buried deep in the earth. [Music] For perhaps a hundred million years, the land sank even lower until the sea washed over it. Marine deposits, ultimately thousands of feet deep, covered the submerged land. [Music] Then, roughly 70 million years ago, the sleeping earth awoke and stretched, lifting the area thousands of feet. Over eons of time, gargantuan upheavalss rearranged the landscape and transformed the ancient scene to a semi-arid desert. It is believed that as the earth heaved and strained, the logs in tomb deep within the overburden cracked and separated at regular intervals as though cut with a chainsaw. Over the millennia, wind and water carved and sculptured the land. These dynamic forces are still at work, eroding away the sediments left by long dead seas. Seasonal rainstorms stalk across the land, drenching the parched earth and washing away particle by particle the sediments and sandstone which have so long encased the petrified logs. [Music] [Music] The process uncovers evidence of lush tropic-like growth and brings to view the fossilized remains of sinister looking creatures. [Music] Gradually, the shape and forms of trees buried by ancient mud up to 200 million years ago are again bathed by a glaring sun. [Music] Eventually, entire logs are exposed. [Music] A mere tick or two ago on the vast scale of geological time, man made his appearance. The Anazi, the ancient ones, were living in the petrified forest about 1500 years ago. Pit houses were used at first, but later more sophisticated dwellings were built of stone and blocks of petrified wood. Several hundred years ago, recurring droughts in the southwest forced the Indians into communal apartments along the riverbanks. Suddenly, and without any real evidence as to where they went or why, they were gone. Left behind were half-finished pieces of pottery, tools, storage vessels, and partially completed meals. Why so sudden a departure? No one knows for certain, and the mute picture language scratched into rocks is no help. The imaginative, highly stylized symbols are themselves largely a mystery. The ancient Indian left his mark upon the land. Yet modern man must tread lightly, lest he destroy the tranquil openness of this remarkable place. The removal of but one sliver of petrified wood defiles the forces which have worked for so long to place it here. A mere 300 ft of logbearing sandstone remains. When wind and water have plained the surface down to this level, all of the petrified wood in this area will lie exposed. There is no more ever. In a few precious places such as this, modern man must curb his technology, restrain his ability to reshape the land to his own needs. There is wonderment and a challenge here for those sensitive enough to understand and accept it. The cyclical growth of all living things. Earth movement so slow that the land seems timeless. Tenuous links with distant ancestors who are part of the brotherhood of man. Ponder these things as you wander among the fallen trees of the petrified forest. Look, touch. Can the mind grapple with a time span of 200 million years? Is it possible to comprehend the complexity of replacing every single wooden cell with microscopic crystals? Or to imagine thousands of feet of sediment and overburden covering these logs? Perhaps not. But at least we can try. [Music]