Bighorn River Research Articles

Tectonic loading and subsidence of intermontane basins: Wyoming foreland province

Research Article| August 01, 1985 Tectonic loading and subsidence of intermontane basins: Wyoming foreland province E. Sven Hagen; E. Sven Hagen 1Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071 Search for other works by this author on: GSW Google Scholar Mark W. Shuster; Mark W. Shuster 1Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071 Search for other works by this author on: GSW Google Scholar Kevin P. Furlong Kevin P. Furlong 2Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802 Search for other works by this author on: GSW Google Scholar Author and Article Information E. Sven Hagen 1Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071 Mark W. Shuster 1Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82071 Kevin P. Furlong 2Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1985) 13 (8): 585–588. https://doi.org/10.1130/0091-7613(1985)13<585:TLASOI>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation E. Sven Hagen, Mark W. Shuster, Kevin P. Furlong; Tectonic loading and subsidence of intermontane basins: Wyoming foreland province. Geology 1985;; 13 (8): 585–588. doi: https://doi.org/10.1130/0091-7613(1985)13<585:TLASOI>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Results of two-dimensional flexural modeling of the northern Bighorn and northern Green River basins in the Wyoming foreland province suggest that these basins formed as flexures in response to loading by basin-margin uplifts and basin sedimentary sequences. The northern Bighorn Basin subsided due to loading by the Beartooth uplift along its western margin. The northern Green River Basin developed as a result of concurrent loading by the Wyoming thrust belt to the west and the Wind River uplift to the east. Tectonic loading from basement-involved uplifts played a major role in subsidence and sedimentation, as evidenced by isopach patterns within each basin. Lithospheric flexural rigidities of 1021 to 1022 newton metres (N·m) can adequately explain subsidence in both basins. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Erosional History of Big Horn Basin: Mackin Revisited: ABSTRACT

The classic study of the erosional history of Big Horn basin is by Mackin in 1937. In it he studied the terrace levels which ranged in age from Late Tertiary to late Pleistocene. He postulated that the terraces were the product of stream captures or intervals of interglacial stability alternating with glacial incision. More recent studies have revised Mackin's classically simple model. Detailed studies have increased the number of terrace levels, changed the timing of their stability episode, and estimated their ages. The number of terrace levels has been increased to nine along the Greybull and Bighorn Rivers and to six along the Shoshoni River. Because some of the different levels occur along each river, the number of unique levels within the basin is 12. The occurrence of a 600,000 and a 100,000 year old ash on two terrace levels allows the ages of the terraces to be estimated. The estimated ages range from 3 m.y. for the Tatman to 49,000 years for the Himes, which is the lowest level along the Bighorn River. Both ashes were deposited during river stability intervals and indicate that the Bighorn River and its eastern tributaries were stable late in the interglac al episodes. In contrast, the glaciofluvial gravels along the Shoshoni River at Cody indicate a late glacial stability episode for the western tributaries. The terrace cycles along the Bighorn River and its western tributaries are therefore out-of-phase. This relationship fostered the numerous stream captures recognized by Mackin, as well as some unusual terrace geometries. Comparison of the estimated terrace ages to termination in the marine isotopic record indicates that not all of the Pleistocene climatic cycles are preserved in the Big Horn basin terrace chronology. The present chronology is currently more complete than that of Mackin's pioneering work of the 1930s, but it has not changed his basic story. End_of_Article - Last_Page 1351------------

The Court-Martial of George Armstrong Custer by Douglas C. Jones, and Wind on the Buffalo Grass: The Indians’ Own Account of the Battle at the Little Big Horn River and the Death of Their Life on the Plains ed. by Leslie Tillett

The Court-Martial of George Armstrong Custer by Douglas C. Jones, and Wind on the Buffalo Grass: The Indians’ Own Account of the Battle at the Little Big Horn River and the Death of Their Life on the Plains ed. by Leslie Tillett

Effects of impoundment on the water quality of the bighorn river

Water flowing through Bighorn Lake, a new impoundment on the Bighorn River, underwent certain physical and chemical changes. Turbidity was greatly reduced and most dissolved constituents lost concentration. Potassium was unchanged over 2 yr, and magnesium, sodium and sulfate diminished one year and increased the next. Nitrate was augmented in the reservoir but other nitrogen compounds suffered reduction. Photosynthetic reduction of alkalinity was not detected and alkalinity decrease is assumed to reflect dilution. Passage through the reservoir delayed conductivity changes evident in the river above, and the mass of stored water was much more resistant to seasonal temperature changes.

Oxfordian Sedimentation in Western Interior, USA: ABSTRACT

Upper Jurassic Oxfordian sediments of Wyoming, Montana, and eastern Idaho were deposited in part of an elongate inland seaway extending southward from the present Arctic. This seaway contained a complex of tectonic elements which influenced significantly the geographic distribution of depositional environments. On the western edge of the Oxfordian seaway (in eastern Idaho), a clastic wedge sequence is developed. Farther east, toward the center of the seaway, complex sequences of marine bars and channels are represented around the edges of the Wind River, Big Horn, and Powder River basins. On the north in Montana, and east in the Black Hills, more typical prodeltaic sequences are developed. Sediment dispersal directions in this seaway were complex due to the interaction of tides, regional currents, depositional environment, and storms. Of these 4 controlling factors, storms may have had the most profound influence, particularly in marine-bar and channel environments. Evidence for storms may be found in coquinoid sandstones. These sandstones are of 2 distinct geometries: (1) sheetlike lags interbedded with silty shales, representing the deposition of reworked shallow benthos in deeper water areas; and (2) channel-fill lags incised into marine bar sediments, representing scours in a shallow marine environment. Vertical successions of Oxfordian sediments display an initial transgressive sequence followed by a well-marked regressive sequence. End_of_Article - Last_Page 606------------

Natural Gas Resources, Rocky Mountain Region

Major gas reserves will be discovered in the Uinta-Piceance, Green River, Laramie-Hanna, Wind River, Big Horn, and Powder River basins in the Rocky Mountain region. In the San Juan and Paradox basins, and in Montana and other peripheral areas, the quantity of additional gas to be discovered is believed to be small. Within the six areas of primary interest, 191,000 cu mi of Cretaceous and Tertiary rocks contain 10 trillion cu ft of gas (reserves plus past production) and 90,000 cu mi of pre-Cretaceous sedimentary rocks contain less than 1 trillion cu ft of gas. Most gas discoveries, therefore, have been in the Cretaceous-Tertiary section and major potential resources probably are confined to these rocks. During the 10-year period 1957-1966, 1,070 gas wells were completed within the six areas; 3.5-4 trillion cu ft of reserves was added. If approximately 1,000 gas wells (plus associated dry holes) are completed within these basins during the 1967-1976 period, an additional 3.5-4 trillion cu ft should be added. Cretaceous-Tertiary rocks occupy approximately 96,200 sq mi, of which only 9,050 sq mi (9.4 percent) has at least one well per square mile. Ten trillion cu ft of gas has been discovered by drilling wells in less than 10 percent of the available area. Less than 5 percent of available rock volume has been explored. If the gas originally in place were 10 times the gas discovered, the ultimate potential would be 100 trillion cu ft. The Potential Gas Committee estimate, 79 trillion cu ft of ultimately discoverable gas in Area H, is conservative.

Gas Potential of Rocky Mountain Region: ABSTRACT

Major gas reserves will be discovered in six Rocky Mountain areas--Uinta-Piceance, Green River, Laramie-Hanna, Wind River, Big Horn, and Powder River basins. In the San Juan and Paradox basins, in Montana, and in other peripheral areas, the quantity of additional gas to be discovered is believed to be small. Within the six areas of primary interest, 191,000 cu mi of Cretaceous and Tertiary rocks contains 10 trillion cu ft of gas (reserves plus past production) and 90,000 cu mi of pre-Cretaceous sedimentary rocks contains only 0.3 trillion cu ft of gas. Most gas discoveries, therefore, have been made in Cretaceous-Tertiary rocks and it is probable that major potential resources will be confined largely to these rocks. During the 10-year period 1957-1967, 1,070 gas wells were completed within the six areas; 3.5-4 trillion cu ft of reserves was added. If approximately 1,000 gas wells (plus associated dry holes) are completed within these basins during the 1967-1977 period, an additional 3.5-4 trillion cu ft should be added. Cretaceous-Tertiary areas occupy approximately 96,200 sq mi and only 9,050 sq mi (9.4%) has at least one well per sq mi. Ten trillion cu ft of gas has been discovered by drilling wells in less than 10% of the available area, and far less than 10% of the available rock volume has been explored. If the gas originally in place is 10 times the gas thus far discovered, the ultimate potential would be 100 trillion cu ft--a maximum estimate. A minimum estimate of ultimate potential should be 25 trillion cu ft. A conservative estimate, between these limits, is 40-50 trillion cu ft to be discovered in the Rocky Mountain region. End_of_Article - Last_Page 211------------

The Little Bighorn River

To the Editor:— The editorial (203: 44, 1968) had Custer making his last stand in Wyoming. As the current Medicine Man for the fighting Cheyennes, I am stationed only a few miles to the east of the famous battleground along the Little Bighorn. We are in Montana, and Wyoming is nearly 100 miles away.

Early Occupations in Bighorn Canyon, Montana

Excavation of the Mangus Site (24CB221) in Bighorn Canyon, Montana revealed a stratum containing artifacts of the Agate Basin Complex. This occupa tion was dated by radiocarbon at 6740 B. C. and 6650 B. C. The Sorenson Site (24CB202) contained two early cultural levels, one of unknown cultural affiliation datedat 5850 B. C. and 5610 B. C. over lying a second unidentified occupation. Future investigations in Bighorn Canyon may produce artifacts allowing identifi cation of these two occupations. Recent archeological salvage investi gations within the Yellowtail Reservoir of south-central Montana have brought to light several occupations of considerable antiquity. In 1962, the River Basin Sur veys of the Smithsonian Institution exca vated a small rock shelter containing evi dence of two occupations dating in excess of 7,000 years but of unknown affiliation. Subsequently, during the 1963 field sea son, artifacts of the Agate Basin com plex were found in a second shelter in the immediate vicinity. A comprehen sive report of these excavations is being deferred until all work in the reservoir area has been completed, but because of general interest in cultural remains of early date, this short, preliminary pa per is presented in order to make avail able two additional radiocarbon dates for the Agate Basin complex, brief de scrip tions of the associated features and arti facts, and data concerning the other ear ly occupations in Bighorn Canyon. The Mangus Site (24CB221), with which this report is primarily concerned, was a small rock shelter located on the left bank of the Bighorn River in Bighorn Canyon about seven airline miles north of the Montana-Wyoming state line in Car bon County, Montana. The shelter was about 55 feet wide and 19 feet deep and was situated at the top of a steep talus slope about 100 feet above the river. The northern end contained dense occu pational debris, but the southern end had a low ceiling and was very narrow, af fording little protected area for living. Three distinct cultural levels were de fined, the lowest of which contained Agate Basin points. The uppermost cul tural level was Late Prehistoric (Mulloy 1958) and occurred as a thick, charcoal laden zone of burned rocks, juniper bark, and artifacts. Deep firepits filled with rock fragments or river cobbles were associated with this level. The inter mediate occupation, in a six-inch thick stratum of reddish limestone rubble and sand, has not been identified but it may be Late Middle Prehistoric (Mulloy 1958). The Agate Basin zone was on, and slightly below, the surface of a stratum of fine, homogenous, light brown sand. The sand overlay reddish limestone rub ble and sand of undetermined depth. The rubble deposit sloped steeply downward 7 This content downloaded from 207.46.13.85 on Sat, 28 May 2016 06:17:49 UTC All use subject to http://about.jstor.org/terms from the rear of the shelter. The sur face of the sand was nearly horizontal; thus, it pinched out near the rear of the cave. Twelve small firepits were found in the Agate Basin level. These varied from oval to circular in outline and had straight or slightly inward-sloping walls and level or slightly concave bottoms. Maximum diameters ranged from 0. 8 to 2. 3 foot with the average being about 1.5 foot. Depths ranged between 0.25 foot and 0. 7 foot and averaged 0. 45 foot. Fill consisted of stained sand and pieces of charcoal. The charcoal varied from scarce to abundant and particle sizes ranged from small bits to moderately large pieces. There was no apparent pattern in the placement of the firepits, but they were concentrated in the area beneath, and a short distance inside, the outer edge of the cave roof. Charcoal from two of the firepits was sent to the Smithsonian Institution Divi sion of Radiation and Organisms for ra diocarbon dating. The results fall very nicely within the suggested time range for the Agate Basin complex of from 8000 B. C. to 5000 B. C. (Roberts 1961: 132). Sample No. SI-98 was dated at 8690 + 100 years B. P. (6740 B. C. ), and Sample No. SI-101 gave a date of 8600 + 100 years B. P. (6650 B. C. ).

Developments in Wyoming and Idaho in 1963

Drilling in Wyoming in 1963 totaled 905 wells, of which 377 were exploratory tests and 528 were development wells. The percentage of success in new-field wildcats was 6.3, and in all exploratory drilling, 13.2. The most active area of the state was the Powder River Basin followed by the Big Horn and Green River Basins. Other parts of Wyoming followed the same general level of activity as in previous years. Idaho had only one well in 1963, an unsuccessful new-field wildcat.

Devonian-Mississippian Englewood Formation in Black Hills, South Dakota

Conodonts indicate that the Englewood Formation of the Black Hills is in part Upper Devonian and in part Lower Mississippian. The conodont fauna which occurs in the middle of the formation at Boxelder Canyon is correlated with a previously described Upper Devonian fauna from the Bighorn and Wind River Mountains. The upper few feet of the Englewood and basal part of the Pahasapa Formation at Boxelder and Whitewood Canyons contain diagnostic Lower Mississippian conodonts.

Developments in Wyoming and Idaho in 1957

The number of exploratory wells, their average depth, total exploratory footage, success ratio and number of discoveries have all increased significantly over 1956. The only decrease was in geophysical activity, which was 36% less than in 1956. The greatest number of discoveries were completed in the Phosphoria formation, followed in order by Frontier, Mesaverde, Dakota, then other formations from Cambrian to Upper Cretaceous. The most exploration activity was in the Powder River basin, mainly in search for stratigraphic traps in Upper Cretaceous sands; which resulted in 3 of the 11 discoveries in the basin. The Bighorn and Wind River basins followed with emphasis on extensions and new pools and structural prospects. The Green River basin led in success ratio with 11 gas and 4 oil discoveries. The Julesburg, Hanna, Laramie, Shirley, and Jackson Hole basins also had a modest amount of exploration. One dry hole was drilled on a structural prospect in Idaho. The emphasis on exploratory drilling for stratigraphic traps has increased and is expected to continue increasing, along with a decline in seismic exploration for structures. There is an increased interest in gas, due to improved economic factors.

Developments in Wyoming and Idaho in 1956

There were 1,026 wells drilled in Wyoming in 1956. The 339 exploratory wells represent the greatest number drilled in any year. There was more development drilling than last year, but less than the peak year of 1954. There were 36 discoveries, of which 80% were Cretaceous. The Powder River basin led in activity, with 34% of the exploratory wells, accounting for 30% of the discoveries. The Green River basin had 12% of the wells, for 30% of the discoveries. The Bighorn and Wind River basins each had about 20% of the exploratory tests and 20% of the discoveries. There were no discoveries in the Hanna, Laramie, and Julesburg basins in the southeast part of the state. Stratigraphic exploration was more extensive than seismic structural work. Discoveries appear disappointing but evaluation of stratigraphic discoveries requires years. Very encouraging development drilling in 1956 at two insignificant discoveries of 1951 and 1953 has established two major stratigraphic oil fields. Stratigraphic plays in the Mesaverde, Phosphoria, and Muddy formations commanded most attention. Several tests of complicated thrust-fault seismic prospects were drilled. Five exploratory wells were drilled in Idaho. No oil or gas was found.

The progressive lag of sediment concentration with flood waves

Numerous investigations of suspended‐sediment discharge have shown that an increase in stream flow usually is accompanied by an increase in sediment concentration. The sediment‐concentration peak during a rise may precede, coincide with, or follow the water‐discharge peak. Observations on the Bighorn River in Wyoming and Montana show a progressive lag in peak concentration behind peak flow. The lag is most apparent when a single storm produces a flood wave that starts many miles upstream from the sampling sections.

Some Features of Redbed Bleaching

Field work in southern Montana has led to the discovery that in certain folds on the flanks of the Bighorn Mountains, the Chugwater redbeds exposed along the crests of minor anticlines are bleached to a clean white color. Oil seeps were noted in the Chugwater sandstone at the south end of one of these anticlines along the Little Bighorn River. Later a much larger mass of oil-saturated rocks was found in the Chugwater formation on the Black dome, southeast of Bridger. These occurrences suggest that oil migrating through the sands causes a reduction of the ferric oxide pigment to a soluble ferrous form in which solution and removal take place. Laboratory experiments showed that no appreciable reduction took place unless the temperature was raised enough to cause cracking of the oil. At such temperatures the reaction was rapid. Further investigation resulted in the discovery that hydrogen sulphide reduces ferric oxide in the cold. This fact has long been made use of by gas chemists in purifying coal gas. In the case of the bleaching near Bridger, it is clear that hydrogen sulphide is a possible agent, for in that locality a spring of water containing a large quantity of that gas was noted. Hydrogen sulphide has been shown to be a common constituent of waters associated with oil. Such waters would probably follow or accompany oil escaping through fissures in an anticline. Therefore, although the bleaching is probably not due to the action of the oil itself on the ferric oxide, it may be considered as a phenomenon associated with the movement of oil through th rocks. Consequently any anticlines whose crests are marked by bleached redbeds should be regarded with suspicion unless possibilities of production exist at a considerable depth.

Overthrust Fault in Nearly Flat Strata

Previous articleNext article FreeOverthrust Fault in Nearly Flat StrataG. Sherburne RogersG. Sherburne Rogers Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Journal of Geology Volume 21, Number 6Sep. - Oct., 1913 Article DOIhttps://doi.org/10.1086/622096 Views: 28Total views on this site PDF download Crossref reports no articles citing this article.

The Hot Springs at Thermopolis, Wyoming

At the southern end of the Bighorn Basin there is a great hot spring which presents some notable geologic features and an interesting question as to the source of the hot water. The spring is at the town of Thermopolis, a village and health resort which owes its existence largely to the reputed therapeutic value of the water. The locality is on the bank of Bighorn River, a few miles north of a high range which may be regarded as the southwestern continuation of the Bighorn Mountains. There are several springs, but one of them has by far the greatest volume. They issue from the red beds, here brought to the surface by a prominent local anticline. The present springs and their predecessors-for the region has been one of thermal activity for many centuries-have built extensive terraces of travertine or hot spring deposits similar to some of those in the Yellowstone National Park.

The First Trip through the Big Horn Cañon

So much has been written respecting our large canons in the West that it seemed as though there was little left to be told. Having occasion last winter to examine the box canon of Big Horn River, the writer was much surprised to learn that the canon had as yet been unexplored. It may be safely stated that this is one of the latest, if not the very last of our large canons to hold out against the explorer. This fact alone has induced the writer to consider his explorations in this canon worthy of special notice. Through southern Montana and northern Wyoming the canon has had the reputation of being impassable. Any one who would attempt its passage was considered not in his right mind, and a prospector who ventured part way down the canon in a boat, was reported in the local press as surely lost.