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Show r- r 1 ' , r - A v -' -, - .'.4 - .- - '- - - - - ,. , , ,"-:..-;.-. ". - ?v, . . ) S.J,,. , - rt-V : :: " -rx - - - f ' v ' . . . V . - : . .. . - v A The descent into a graben called Bobbys Hole near the south border of Canyonlands Naticrtal Park is a rough jeep trip. (T-I Staff Photo) Travel Writer Explores "Grabens," Tests Acclaimed Bobbys Hole Nil! by Dick Wilson Bobbys Hole is an excellent excel-lent example of a graben. You say you don't know what a graben is? If you are reading this article in Moao then you are sitting in a graben. gra-ben. A geologist defines the term "graben" as a block depressed between two faults. The word "graben" is derived from the German language and has a meaning mean-ing of "trough" or ditch. Such a feature as recognized by geologists is formed when a piece of land sinks between two faults leaving adjacent land higher. There are many well known grabens in the United Unit-ed States and the world, but people generally don't know them as graben. The term "graben" explains their origin. ori-gin. Death Valley in California is one of the more outstanding outstand-ing grabens. The Great Rift Valley of eastern Africa ;s a tremendous crack in the ground stretching all the way from Lake Nyasa to Jordon in Palestine. The Red Sea is part of the Great Rift Valley Val-ley which extends through the Dead Sea and the Jordon River bed. In Utah and Nevada Ne-vada a number of valleys are graben types. Southeast Utah is famous for its grabens. The Moab and Spanish Valley, Paradox. Salt, Fisher, Castle, Lisbon and Sinbad are among more noteworthy grabens. The Needles section of Canyonlands Can-yonlands National Park is mostly the result of fault and graben action. Chesler and Virginia Parks, Devils Lane, Cyclone Canyon are a-mong a-mong the more than 20 grabens known in the Needles. Need-les. Bobbys Hole is one of these sunken valleys characterizing characteriz-ing the Needles District, through this particular valley val-ley is just south of the Can yonlands Park boundry. Bobbys Hole forms an interesting in-teresting avenue between two cliffs an avenue that makes access possible from the Chesler Park area south to Beef Basin. It is an adventurous ad-venturous jeep trail that follows fol-lows the series of grabens that one encounters on the west side of Elephant Hill. I recently toured Bobbys Hole coming from the south. I was driving a dune buggy which had an annoying habit hab-it of locking both front wheels as I would step forcefully force-fully on the brakes. When rounding curves in the rough' jeep track the dune buggy, when being braked, would tend to continue in a forwerd direction rather than making mak-ing the turn. This didn't give me too much concern till I began the descent into Bobbys Hole from the Pappys Pasture and Ruin Park direction. The jeep trail was carved into the side of the cliff, dugway style, and presents a w-onder ful view of the valley floor ' and the graben effect. When passing around a gentle curve, I stepped on the braK-es braK-es to hold back my vehicle. Instead of going around the curve, my dune buggy slid straight forward to the edge and didn't stop until my left front tire was hanging over the precipitous edge. Th was one time that I was ready to bail out and I would have done this with another inche's progress toward the edge. I set my emergency brake and got out of my buggy. I lifted the front end of the fiberglass fi-berglass rig and set it bpk into the proper jeep tracks and continued the merry ride to the valley bottom. The trail through Bobbys (Continued m Page B2) Travel Fun in the Graben Country (Ccnti-Tiued from Page Bl) Hose is going to remain a jeep access to the southern entrance of Canyonlands National Na-tional Park according to present park plans. The proposed pro-posed hard-surface automobile automo-bile route to Chcsler Park will be some three or four miles to the east in the viefnj ity of Butler Wash. So regardless re-gardless of coming developments, develop-ments, there will be an adventurous ad-venturous jeep trail on the other side of Elephant Hill for jeep fans to follow. Immediately at the bottom of the dugway which gives access to Bobbys Hole is something worth looking into To the west of the trail a-gainst a-gainst the cliff I spotted what appeared to be a de't depression. de-pression. I stopped my vehicle ve-hicle and walked over. Sur.? enough, here was a good sized sink in the bottom of Bobbys Hole. On approaching approach-ing it I recalled the caves of Tennessee and Kentucky which many times are entered en-tered through such sink hole entrances. I was sweating by the time I got over to the edge of the pit, not so much from exertion exer-tion but rather from the fact that it was a very warm day. I plunged down the sandy slope into the bottom of the depression noticing black cracks immediately a-gainst a-gainst the fault scarp. Cool air was blowing from the cracks, a sign of large cavities beneath. The cracks were wide enough to allow an explorer to get in but no means cf light. I refrained from doing so. But my curiosity cur-iosity is up. Next time to Bobbys Hole I want to take a deep look into those crevices. crev-ices. Not only were the sink- : , - ft Zmi .jtd-m. S. . ? - : i " ' - . ' i . :' i. ,:. 4 , . A fragile formation lis Horsehoof Arch, a feature recently brought to the altantion cf the public by Mitch Williams. type crevices in this one location, lo-cation, but in several places along the trail in Bobbys Hole. That one near the dugway dug-way going out to Ruin Park, however, had them all beat as far as depth was concerned concern-ed "A graben within a gra-ben." gra-ben." I told myself, and a very curious feature to observe. ob-serve. How far down those holes go is anyone's guess for they haven't been investigated. inves-tigated. Later Bates Wilson inform ed me that several cows had iost their lives when getting too near the crevices in the grabens. "They are very dangerous," danger-ous," he said. "They look quite solid on the surface but have been undercut and when extra weight is brought to bear on them, the grour.J gives way." Robert Norman, a member of the American Association of Petroleum Geology. st.V.-ed st.V.-ed that the grabens of this area were formed as a result re-sult of dissolution activity. "Portions of the intrusive salt beds that underlie southeast I'tah." Norman said, "were dissolved by subsurface sub-surface water leaving a cavity. cav-ity. When the cavity wouli become large enough, a block of the overlying structure struc-ture would give way and sink to a lower level." "This is a process that is going on today." lie added. About 2';00 years ago however how-ever rainfall was greater and the resulting dissolution activity was promoting graben gra-ben development at a faster pace." There are other wonderful features to see on the rou'.1 to Bobbys Hole. Just past the Chesler Canyon intersection intersec-tion is a jeep trail heading west from the main trail. It leads to Horsehoof Arch a feature brought to the attention at-tention of the public about two years ago by Mitch Williams. Wil-liams. Previously photographed by the Gregory family of Vancouver, British Columbia Horsehoof is a perfect name for the feature. You can study horse anatomy when visiting this arch for it displays dis-plays not only the hoof but the fetlock and lower front leg of the horse. It's a very fragile - looking arch, ona that sonic booms will do no good. Take that jeep trail that goes through the bottoms of the grabens on the other side of Elephant Hill. Follow it past Horsehoof Arch and through Bobby Hole. I thinV you'll agree that grabc-n and the associated features are amazing and fascinating portions of our Canyon Country. |