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Show ) once SID J, ...... -W - . - . . . . ' . - S . " "' " .. '. "S?;, -v "" -- ---. ' ' . . ' . . -a " -Tr v " ' . . ' i dr, : . i.v.5"- v.vsr - - 1 3 ' --.w - .- v -srv ; - - , n . , - J , . , . r - . : 1 , . v - ' - - . y , V . J IK , -S " . s -. "7- . , ' ,y ' 'j .-tone- layer stacked on top of layer. It all adds up to "environ-:;llt." "environ-:;llt." Southeastern Utah is typified by this scene of the canyon country xiTjFrom the Canyons . . . W-Sfcll National Park Service Vff?j:'l Department of the Interior j Syy Canyonlands Arches Bridges Canyon; . Ranger Phil Hastings Hast-ings attended Harpers Ferry, Fer-ry, and Ranger Herb Ger-cke Ger-cke will leave this month for the U.S. Park Police recruit re-cruit School in Washington. D. C. Naturalist Charles Parkinson, ' author of today's feature below, is slated for Harpers Ferry in mid-November. Perhaps as you look at this red rock land all you see is a confusion of rocks, canyons, spires and pinacles that frequently leave you (perplexed and always astounded. as-tounded. Perhaps you try to relate rocks and shapes seen other places with what you see here. Sometimes you are successful, sometimes not. On a visit to Arches, or Canyonlands, or Natural Bridges, you might ask this question. "What is the name cf that roek, there along the cliff line?" We answer, "It is the Wingate formation (or Entrada, or Cedar Mesa or whatever it might be)." Then we might see you frown, and hear you reply-that reply-that it looks just like another anoth-er formation you . saw at Grand Canyon, for example, (but there it was called by another name. Or you might wonder why a formation called by one name here doesn't look like a formation forma-tion by the same name in southwestern Utah. Although you don't know it, you have partially answered ans-wered your, own question. You have observed similarities similar-ities and differences in the rocks you saw on your travels. trav-els. You need know but one more piece of information in order to solve the problem. One, we all know that rock formations are stacked up in layers, one on top of the other. We also know that n a layered rock sequence, the oldest layer is on the bottom of the pile and the youngest young-est is on the top. Now just think a minute about all the thousands of feet of layered rock that have formed since the beginning of geologic time. Some persistent sedimentary sedi-mentary basins contain 83 to 100 thousand feet of layered rock. It stands to reason that in all that vast pile ot rock, many of the layers are going to look similar in appearance. ap-pearance. Why this is so the problem that confronts ibolh you and the geology. The answer can be rednc ed to one simple word,, en- viewed from a canyon rim overlook south of Moab. jinvironmeitf is Where You Live 1 L- 'is is back to school sea-; sea-; for National Park Serv-: Serv-: personnel. Most of the "" Hvisory staff of the Can-iads Can-iads Complex have been ;re scheduled to attend i ; of the designated train-G( train-G( ; schools the Horace Albright Training Cen-js Cen-js ; at Grand Canyon; the P in T. Mather Training I 3r at Harpers Ferry, st Virginia; or the Park :ce Training School, at '. iington, D. C. i m training centers are i :ed to Park Service j -k Experts in all fields n 2 inside and out of the ice, are called upon to 1 :.i NPS personnel. Folia; Fol-ia; the formal 11-week Mj, a new employee rpletes a year's tour of ' in a designated train--: park before he is sent to "Mnent duty station. If : has done his homework, -anger is equipped to han-; han-; any situation that may s - in law enforcement, I ministration, visitor use, fl sction of resources, ;;!er planning, on budget-i budget-i and legislative mandates a which Parks are op- 5e basic mission of Nasi Na-si Parks and Monuments always been to preserve 'Ml features unimpaired the enjoyment of the i. Parks are bench-is. bench-is. where the public can '' 'or themselves what con's con-'s once were and relate to present conditions. ;-acs Stenger, former writer-historian and to of "Beyond the 100th n", caiis them a phy of Hope". The ;or'al Park schools boi-the boi-the expression as a goal, and environ-awareness environ-awareness is now an ;al part of most train- ssions. !,railling is constantly be- updated, and each Fall .:J the pressures of vis-T vis-T Service are lilted, park lwl are shuttled to i, Canyonlands Fall have included Na- BiH Taylor, Harpers 3; Ranger Tom Bredow ; ger Charles Budge H Maintenance Superin-!Joe Superin-!Joe Miller, Grand vironment. Now, where you live is your . environment --geography, --geography, climate, the living liv-ing world around , you. It may be along the sea shore, in a desert or mountain country. Or, environment may mean the entire earth. Rocks also exist in and were formed in an environment environ-ment environment in a more technical sense, meaning mean-ing a set of conditions. Most rocks in our area were deposited de-posited as sediment along shore lines, beaches, deserts des-erts and river flood plains. Two rock formations may look the same, but have different dif-ferent names. They look the same because both layers were deposited in similar environments, en-vironments, such as along the coast of an ancient shore line. They have different differ-ent names because they are of different ages. The key factor is that the environment environ-ment which produced the two layers repeated itself in geologic history. Sometimes a thick rock layer, such as the Entrada sandstone, will look homogeneous, but is actually a product of several environments. In our area, a sea covered the land during Entrada time. Moab was near the edge of this sea. At times the shoreline was west of here and we were "on the beach." Occasionally Occasional-ly the shoreline moved east and we were under water. The ' sands that built up to form the 330-ft. thick Entrada En-trada deposits are a combination combi-nation of beach and sand dunes formed when this land was exposed and offshore bar sands deposited at this time. ' The Navajo sandstone is an excellent example of a thick rock layer that was deposited under only cr.e environment. The Navajo is a rock unit composed of desert dune sands. When it was deposited, much of the southwest was a vast desert-The desert-The country probably looked like the present day Sahara Desert. Once you see the Navajo formation in one place, you .will have little diKicuhy recognizing it somewhere else. Now lot's take, for example, ex-ample, one local rock formation for-mation made of maroon sandstone. It is very distinctive distinc-tive because of its color and it has a certain name. 203 miles west of here a light grey limestone formation is called by the same name. You see nothing similar about the two, but they still are called the same formation. forma-tion. What has happened? Rock bodies have thickness, width and length. They may cover thousands of square miles. The formation was deposited in sedimentary-basins sedimentary-basins (The basins can be shallow or deep, lake cr . ocean; and bordered by shorelines). Along this particular par-ticular shoreline, red and maroon sands were deposited deposit-ed at the river mouths. Streams, heavily laden with material, carried the sediments sedi-ments from nearby mountains. moun-tains. When they flowed into the open sea, they dropped much of their load of the river. Delta deposits of red and maroon mud built up. However, not all of the sediment sedi-ment was deposited along the deltas. Some of it was carried seaward. The finer, smaller grains were deposited depos-ited farther out from the shoreline as silts. Even further fur-ther seaward, some 200 miles, mi-les, no sand or silt clouded the water. It was clear. But deposition of another kind still went on deposition in the form of limestone accumulation. ac-cumulation. Millions of tiny shelled creatures lived (and live today) in the sea. When they die, their shells, containing con-taining calcium carbonate, accumulate on the sea floor. Now this happened both near shore and out in the middle of the ocean. But nearer shore so much more mud and sand was being deposited de-posited that it overwhelmed overwhelm-ed the smaller amounts ot shell debris. Out in the ocean no sand contaminated the shell material. Limestone deposits wrere permitted to build up. Remember this occurred oc-curred at the same time the maroon muds built up their deposits in our area. After all this was over, the seii-. seii-. ment buried, hardened . into rock and then uplifted and exposed to man's eye, tlv geologist came along to map this varied rock unit. He mapped the rock as it outcropped out-cropped between here and the region 230 miles west of here. He recognized that the maroon sandstone and the distant limestone wer3 part of the same formation deposited at the same time. He - and we - call it the Car-mel Car-mel formation. Much mere exists to this stcry about rocks. Here in Southeast Utah we live in one of the best outdoor rock laboratories in the world. We have everything from salt domes to redrock canyons can-yons to the igneous LaSi'l mountains. So, as you look at the rocks, remember that they were not formed in a vacuum. They were formed in an environment whose understanding is essential es-sential in unraveling the rock story. Canyonlands Sam Says: "The United States has one sixth of the worlds population. popula-tion. It consumes 40 percent of the world's products". |