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Showing 1 to 9 of 9 (0.047 seconds)Spelling suggestions: "subject:"make bonneville"" "subject:"make sonneville""
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Characteristic and Genesis of Some Soils of the Upper Terraces of Lake BonnevilleMirsadeghi, Mohammad Ali Haji 01 May 1980 (has links)
The genesis and characteristics of the Timpanogos, Hillfield, and Sterling soils and an unnamed Mollisol (soil formed on north- slope) on the east part of Cache Valley were studied in order to determine (1) why the soil morphology is not chronologically related to the geomorphic surface and (2} why different soils have developed on these surfaces , even though the soil forming factors appear similar.
The particle size distribution of the upper horizons of the Timpanogos, Hillfield , and unnamed Mollisol pedons are relatively similar . These soils developed from stratified deposits with granulimetric composition in which 75 to 90 percent of the grains are less than 100 micrometers in diameter , characteristic of wind-blown material. Development of an incipient argillic horizon in Timpanogos pedon indicates this soil did not develop under the moist conditions of the Pleistocene and the geomorphic surface was not stable after deposition. The material was reworked by the wind. The Sterling soil formed on an alluvial fan which was deposited during Holocene time and its development is chronologically related to geomorphic surface.
The development of an incipient argillic horizon in the Timpanogos soil and a weak cambic horizon in the Hillfield soil and the unnamed Mollisol is due to topographic condition of the landscapes.
The thick and dark mollie epipedon in the unnamed Mollisol (north-slope) compared to the Hillfield soil (south- s lope) which has an epipedon with color light to be mollie and a less thick A horizon is related to effect of microclimate.
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THE QUATERNARY GEOLOGY AND SEQUENCE STRATIGRAPHY OF THE LAKE BONNEVILLE DEPOSITS IN THE MATLIN QUADRANGLE, BOX ELDER COUNTY, NORTHWESTERN UTAHCavas, Matthew P. January 2003 (has links)
No description available.
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Insights into the Early Transgressive History of Lake Bonneville from Stratigraphic Investigation of Pilot Valley Playa, UT/NV, USARey, Kevin A. 30 October 2012 (has links) (PDF)
Multiple shallow sediment cores were obtained from Pilot Valley playa, a sub-basin located in the northwestern Bonneville basin. Analysis of stratigraphy, ostracodes, mineralogy, chemistry, total inorganic carbon (TIC), total organic carbon (TOC), and stable isotopes were performed to better place these sediments into proper context with respect to the Lake Bonneville cycle. Results showed Pilot Valley playa contains a nearly full sequence of Lake Bonneville deep-water marl in addition to sediments deposited before and after the Lake Bonneville cycle. Within the marl is a sequence of organic rich algal laminated marl correlated with the Stansbury oscillation. Four 14C ages ranging from ~22.4 k 14C years to ~15.8 k 14C years from preserved algae filaments in this sequence place it well within the time frame of the Stansbury oscillation. Oolitic sand found below this sequence indicates the existence of a shallow (<~5 m), saline lake in Pilot Valley prior to the transgression of Lake Bonneville. Analysis of sediments deposited during the late regressive phase of Lake Bonneville indicates the lake may have fallen to levels below that of Pilot Valley prior to transgressing to the Gilbert level.
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A Geophysical and Geological Analysis of a Regressive-Phase Lake Bonneville Deposit, Pilot Valley, NVSmith, Katelynn Marie 01 April 2018 (has links)
Pilot Valley, located in the eastern Basin and Range, north of Wendover, UT, contains numerous shorelines and depositional remnants of late Pleistocene Lake Bonneville. These remnants present classic ground penetrating radar (GPR) targets due to their coherent stratification, low clay, low salinity, and low moisture content. Three-dimensional (3D) GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters. While lake levels fluctuated due to flooding events, climatic changes were the dominant factor in controlling lake levels. In Pilot Valley, the paleowind entered from the northwest, with storms coming from the south, and circulated clockwise around the basin, forming offshore sand bars. On the western side of the valley, a uniquely well-preserved interpreted regressive phase beach deposit, dated late Pleistocene, is hypothesized to have been a point bar shortly after the Provo Shoreline period. 3D GPR data, measured stratigraphic sections, cores, mineralogical analysis, and the collection of gastropod samples for radiocarbon dating constrain a reconstruction of the deposit's depositional environment and local paleoclimate for Lake Bonneville. The GPR images, visualized with state-of-the-art petroleum industry tools, reveal fine-scale stratigraphic detail that can be analyzed using seismic stratigraphy concepts. Our study provides a comprehensive model for ancient pluvial lake-shore depositional environments in a Basin and Range setting using an integration of geological and geophysical data.
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Investigating the margins of Pleistocene lake deposits with high-resolution seismic reflection in Pilot Valley, UtahSouth, John V. 11 November 2008 (has links) (PDF)
A vast area of the northeastern Great Basin of the western USA was inundated by a succession of Plio-Pleistocene lakes, including Lake Bonneville (28 ka to 12 ka). The Pilot Valley playa, located just east of the Utah-Nevada border near Wendover, Utah, within the eastern Basin and Range Province, represents an 8 to 16 km wide and ~50 km long remnant of these lakes. The playa corresponds to the upper surface of a closed basin that is delimited by two mountain ranges, which are mantled by recent alluvial fans over which the playa sediments have prograded. In order to investigate the interaction of Plio- Pleistocene lake sedimentation and alluvial fan development, high-resolution seismic reflection profiles have been acquired near the base of both the west-bounding and the east-bounding ranges. On the western side of the basin, the seismic profiles provide images of sub-horizontal playa sediments prograding over the inclined alluvial fans. Theboundary between the playa and fan sediments is marked by a prominent angular unconformity. Seismic images from the eastern side of the basin reveal a markedly different structural and stratigraphic style with down-to-the-basin normal faulting of relatively shallow Paleozoic bedrock overlain by alluvial fan deposits, which are in turn on-lapped by a thin veneer of playa sediments. The results contained herein reveal for the first time the stratigraphic relationships between Quaternary pluvial sediments as a shoreline depositional facies and the adjacent bounding fan deposits. Post-stack reprocessing of lower-resolution but deeper penetration seismic data located in an analogous basin to the southwest, provides a likely context for the Pilot Valley seismic data. The new geophysical images, when integrated with available geologic mapping and limited well control, aid in constraining how deep aquifers are locally recharged from an adjacent range. The results also clearly demonstrate the strong structural asymmetry of the range and playa system, which is consistent with a classic half-graben structure. Lastly, this study demonstrates the utility of the shallow seismic reflection method as a tool to provide high-resolution sub-surface images in the geophysically challenging environment of Basin and Range geology.
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An Analog for Large-Scale Lacustrine Deposits: 3D Characterization of a Pleistocene Lake Bonneville SpitLopez, Eli D. 07 September 2022 (has links)
Ultra-high-resolution subsurface stratigraphy mapped from 3D ground-penetrating radar (GPR) can provide insights into the fine-scale heterogeneity of reservoirs and other geologic features. Analog models derived from 3D GPR aid in understanding reservoir compartmentalization that may be sub-seismic but still affect fluid flow. We integrate 2D profiles and 3D GPR volumes with measured stratigraphic sections from outcrop exposure to characterize the fine-scale stratigraphy of an ancient Lake Bonneville shoreline deposit (locally, circa 20 ka based on carbon-14 dating) in the Great Basin (northwestern Utah). The heterogeneity of the deposit is expressed as multiple discordant patterns, separated by unconformities that likely were influenced by fluctuating lake levels on the lake margin. Although the study site is only ~8,000 square meters in area, the detailed stratigraphic relationships can be scaled up to inform the characterization of larger sedimentary deposits with economic reservoir potential. The sands, gravels, and marls composing the stratigraphy were deposited during the transgressive phase of the pluvial lake, which preserved shoreline features such as spits and barrier bars. We interpret our site as a spit that extended out into the Pleistocene lake, at times connecting to a nearby persistently subaerially exposed island to form a tombolo. The deposited strata are well-exposed in a fortuitously located gravel quarry. The site provides an excellent natural laboratory for detailed 3D imaging due to the mostly flat ground surface (the quarry floor), low-clay, low-salinity, and low-moisture content of the site. The GPR data were acquired with a 200-MHz antenna (for 2D profiles) and a 400-MHz antenna (for 3D volumes). For the latter, the line spacing was about 0.3 meters with a trace spacing of 2.5 cm. The GPR dataset offers high-resolution images of clinoform sequence stratigraphy down to about 3 meters below the surface of the quarry. The vertical resolution (Rayleigh criterion) of the data is about 6 cm (for 3D volumes) and 13 cm (for 2D profiles). Migration collapsed diffractions and re-positioned dipping reflectors correctly. Deconvolution suppressed multiple reflections and tightened the waveforms. Using petroleum industry mapping software, amplitudes were binned into voxels to create precise 3D volumes, which facilitated more accurate geometrical interpretation (e.g., true dip direction of reflectors). Facies associations from stratigraphic sections measured just above the GPR acquisition level (quarry floor) help to describe and reconstruct the depositional history of the spit. The lithologic interpretation of the GPR reflectors is constrained by the correlation (or extrapolation) of the measured sections to the subsurface data volumes. Reflectivity is controlled by variations in porosity and matrix content (e.g., quartz vs. clays vs. calcite). Our study furnishes a model of transgressive deposits in a lacustrine environment and an analog for clastic sediments deposited on a larger scale in such environments.
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Wetlands on the Thousand Lake Mountain Mega-Landslide as Paleoclimate ProxiesShurtliff, Ryan Andros 24 June 2014 (has links) (PDF)
The Windy Ridge mega-landslide in Wayne and Sevier Counties originated in Lates tPleistocene time as established by 14C ages on basal organic-rich clay and peat sediment from bogs that developed on the slide. The contact depth between bog and landslide was estimated using high-resolution seismic reflection to find the thickest sediment. Four bogs were cored at their depocenters, and organic material at the slide contact was used for age determinations. The oldest bog sediments ages are 10,600 ± 46, 10,556 ± 34, 12,511 ± 134, and 12,886 ± 91 calibrated years BP. Ages represent two sliding events. First, at the transition from interglacial to younger Dryas glaciation, coeval with the transgression of the Gilbert stand of Lake Bonneville. Younger ages suggest a second slide at ~10,550 cal ka BP. Carbon and nitrogen stable isotopes, and pollen contain a detailed sedimentary record of climate changes since the younger Dryas Chronozone (YDC). The Windy Ridge Mega-Landslide, together with other proxies in the region, provide strong support for a wet period during the transition from late interglacial to glacial conditions at the onset of YDC. Pollen records of this time span are rare in Utah, where local climate variation is complex and illustrates the strength of using landslide bogs as paleoclimate proxies.
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Multispectral and Hyperspectral Remote Sensing of Quaternary Sediments in Tule and Snake Valleys, Lake Bonneville, UtahHassani, Kianoosh January 2017 (has links)
No description available.
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Ghost Water ExhibitionSharp, Michael G. 01 March 2017 (has links)
The Ghost Water exhibition of artworks by Michael Sharp was comprised of four main works titled: 30 x 60 Minute Grid Series, Suspension, History/Prehistory, and Lake Bonneville Remnants. The artwork was created as a reaction to the land that once held the prehistoric Lake Bonneville and to its current remnant Great Salt Lake. The work explores the dialogue between absence and presence.
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