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At least 865 records · Page 48Linked to original sources
USGS2000

High-resolution seismic reflection to delineate shallow gas in Eastern Kansas

Unique amplitude characteristics of shallow gas sands within Pennsylvanian clastic-carbonate dominated sequences are discernible on high-resolution seismic reflection data in eastern Kansas. Upward grading sequences of sand into shale represent a potential gas reservoir with a low-impedence acoustic contrast at the base of the encasing layer. The gas sand and encasing shale, which define the gas reservoir studied here, are part of an erosional incised valley where about 30 m of carbonates and shale have been replaced by sandstone and shale confined to the incised valley. These consolidated geologic settings would normally possess high impedence gas sand reservoirs as defined by abrupt contacts between the gas sand and encasing shale. Based orr core and borehole logs, the gas sand studied here grades from sand into shale in a fashion analogous to that observed in classic low-impedance environments. Amplitude and phase characteristics of high-resolution seismic data across this approximately 400-m wide gas sand are indicative of a low-impedance reservoir. Shot gathers possess classic amplitude with offsett-dependent characteristics which are manifeted on the stacked section as "bright spots." Dominant Frequencies of around 120 Hz allow detection of several reflectors within the 30+ meters of sand/shale that make up this localized gas-rich incised valley fill. The gradational nature of the trapping mechanism observed in this gas reservoir would make detection with conventional seismic reflection methods unlikely.

The Compass: Earth Science Journal of Sigma Gamma ↗
USGS2000

The origin and development of plains-type folds during the cretaceous in Central and western Kansas

Kansas is part of the Central Stable Region of North America. Structural movement on this part of the craton has been mainly the result of tectonism in nearby areas. Response to the outside tectonic forces, transmitted through the rigid Precambrian basement, has been vertical adjustment. Differential movement along an indigenous fault/fracture pattern in the basement created displaced blocks over which the later sediments were draped by differential compaction. After initial formation of this structural regimen in late Mississippian-early Pennsylvanian time, continued movement of the basement blocks gave rise to the plains-type folds so prevalent in the U.S. Midcontinent. The incremental movement continues through the late Paleozoic, Mesozoic, and Tertiary until today. This paper demonstrates the Cretaceous development of some of these structures in central and western Kansas.

The Compass: Earth Science Journal of Sigma Gamma ↗
USGS2000

Carbonate-shelf depositional environments of the Ordovician Viola formation in South-Central Kansas

The Upper Ordovician Viola Formation, an important petroleum reservoir in the Midcontinent, is a carbonate unit present over much of the subsurface in Kansas. The Viola is composed of two fining-upward sedimentary packages that are separated from each other by a minor karstic surface representing a brief period of exposure. Each package represents a third-order sedimentary cycle and consists of an echinoderm-rich packstone overlain by a thicker lime mudstone. The echinoderm-rich packstone was deposited nearshore in agitated waters, but subsequently was bioturbated. The overlying lime mudstone was deposited in deeper, quiet waters, and locally contains storm-deposited carbonate sands. Subtle growth of the Central Kansas Arch and Pratt Anticline (structures transecting the depositional shelf) is indicated by packstones and grainstones being thicker over these arches, whereas finer grained lithologies dominate in basinal areas on the arch flanks. Structureless lime mudstones, probably intensely bioturbated, grade into laminated lime mudstones farther basinward.

The Compass: Earth Science Journal of Sigma Gamma ↗
USGS2000

Assessing the Kansas water-level monitoring program: An example of the application of classical statistics to a geological problem

Geologists may feel that geological data are not amenable to statistical analysis, or at best require specialized approaches such as nonparametric statistics and geostatistics. However, there are many circumstances, particularly in systematic studies conducted for environmental or regulatory purposes, where traditional parametric statistical procedures can be beneficial. An example is the application of analysis of variance to data collected in an annual program of measuring groundwater levels in Kansas. Influences such as well conditions, operator effects, and use of the water can be assessed and wells that yield less reliable measurements can be identified. Such statistical studies have resulted in yearly improvements in the quality and reliability of the collected hydrologic data. Similar benefits may be achieved in other geological studies by the appropriate use of classical statistical tools.

The Compass: Earth Science Journal of Sigma Gamma ↗
USGS2000

Kansas coal distribution, resources, and potential for coalbed methane

100 ft (>30 m)] determined from 32 different coal beds. Strippable coal resources at a depth < 100 ft (<30 m) total 2.8 billion tons (2.6 billion MT), and this total is determined from 17 coals. Coal beds present in the Cherokee Group (Middle Pennsylvanian) represent most of these coal resource totals. Deep coal beds with the largest resource totals include the Bevier, Mineral, \"Aw\" (unnamed coal bed), Riverton, and Weir-Pittsburg coals, all within the Cherokee Group. Based on chemical analyses, coals in the southeastern part of the state are generally high volatile A bituminous, whereas coals in the east-central and northeastern part of the state are high-volatile B bituminous coals. The primary concern of coal beds in Kansas for deep mining or development of coalbed methane is the thin nature [<2 ft (0.6 m)] of most coal beds. Present production of coalbed methane is centered mainly in the southern Wilson/northern Montgomery County area of southeastern Kansas where methane is produced from the Mulky, Weir-Pittsburg, and Riverton coals."}" data-sheets-userformat="{"2":8403202,"4":[null,2,16777215],"11":4,"14":[null,2,0],"15":"Inconsolata, monospace, arial, sans, sans-serif","16":11,"26":400}" data-sheets-formula="=VLOOKUP(R[0]C[-5],Fixed!R2C[-6]:C[-4],3,false)">Kansas has large amounts of bituminous coal both at the surface and in the subsurface of eastern Kansas. Preliminary studies indicate at least 53 billion tons (48 billion MT) of deep coal [>100 ft (>30 m)] determined from 32 different coal beds. Strippable coal resources at a depth < 100 ft (<30 m) total 2.8 billion tons (2.6 billion MT), and this total is determined from 17 coals. Coal beds present in the Cherokee Group (Middle Pennsylvanian) represent most of these coal resource totals. Deep coal beds with the largest resource totals include the Bevier, Mineral, "Aw" (unnamed coal bed), Riverton, and Weir-Pittsburg coals, all within the Cherokee Group. Based on chemical analyses, coals in the southeastern part of the state are generally high volatile A bituminous, whereas coals in the east-central and northeastern part of the state are high-volatile B bituminous coals. The primary concern of coal beds in Kansas for deep mining or development of coalbed methane is the thin nature [<2 ft (0.6 m)] of most coal beds. Present production of coalbed methane is centered mainly in the southern Wilson/northern Montgomery County area of southeastern Kansas where methane is produced from the Mulky, Weir-Pittsburg, and Riverton coals.

Kansas↗
USGS2003

The Hula Valley subsurface structure inferred from gravity data

We use the 3-D gravity inversion technique to model the shape of the Hula basin, a pull-apart basin along the Dead Sea Transform. The interpretation was constrained using the Notera-3-well density logs and current geological knowledge. The model obtained by inversion shows a rhomb-shaped graben filled with approximately 4 km of young sediments in the deepest part of the basin. The reliability of this model was verified using 3-D forward modeling with an accuracy of 0.5 km. Curvature attributes of the gravity field depict the main fault pattern, suggesting that the Hula basin is a subsiding rhomb-shaped graben, bordered by steep-sided, deep basement faults on the western and eastern sides (Qiryat Shemona and Jordan River faults) and by gradual, en-echelon step faults on the southern and northern margins of the basin. ?? 2003 Laser Pages Publishing Ltd.

Israel Journal of Earth Sciences↗
USGS2007

Reconstructing late Cenozoic stream gradients from high-level chert gravels in central Eastern Kansas

Interpreting the evolution of Kansas' landscape east of the Flint Hills provides major challenges. In the Neogene (late Tertiary) and perhaps part of the Pleistocene, streams transported a variety of sedimentary materials, including chert gravels derived from the Flint Hills. Gentle intermittent uplift stimulated the system system to cut down, locally removing and reworking the gravels to create stream-terrace deposits that consist mostly of chert pebbles, which now lie well above the floodplains of modern streams. By correlating the elevations of these gravels, the gradients of the trunk streams that deposited them can be reconstructed. Interestingly, these ancient streams flowed southeast at a little more than a foot per mile (0.2 m/km), roughly the same as the gradient of the trunk streams in the region today. The evolving landscape in eastern Kansas also has been strongly influenced by an extensive network of fractures that is widespread in the midcontinent region and may be worldwide in extent. In northeastern Kansas, glaciation during the Pleistocene disrupted the southeasterly drainage and established the present location of the Kansas River. South of the Kansas River and its immediate tributaries, however, the general southeasterly drainage has been preserved. We have made use of the wealth of topographic-elevation data now available in digital form known as DEMs or digital elevation models. Coupled with GIS procedures, the DEMs helped link the mapped distribution of chert gravels with hypothetical fitted surfaces that represent ancient stream gradients. Furthermore, DEM data placed in shaded-relief map form emphasize the influence of fractures in evolution of the drainage system.

Current Research in Earth Sciences↗
USGS2007

Palynological correlation of Atokan and lower desmoinesian (Pennsylvanian) strata between the Illinois basin and the Forest City basin in Eastern Kansas

Palynological correlation is made between Atokan and lower Desmoinesian strata in the Illinois basin an the Forest City basin in eastern Kansas. Spore data from previous studies of coals in the Illinois basin and other coal basins are compared with data from spore assemblages in coal and carbonaceous shale bands in a core drilled in Leavenworth County, Kansas. Correlations are based on first and/or last occurrences of 31 species common to the Illinois basin and eastern Kansas and on significant increases or decreases in abundance of several of those taxa. The oldest coal, which is 26 ft (8 m) above the top of the Mississippian, is early Atokan (early Westphalian B) in age and is approximately equivalent to the Bell coal bed in the Illinois basin. The Riverton coal bed at the top of the studied interval in Kansas is early Desmoinesian (early Westphalian D) and correlates with about the Lewisport coal bed in the Illinois basin. Three coal beds near the base of the Pennsylvanian in three cores drilled in Cherokee County, Kansas, which were also studied, range in age from late Atokan to early Desmoinesian. As in other coal basins, Lycospora, borne by lycopod trees, greatly dominates the lower and middle Atokan spore assemblages in coals and shale, but spores from ferns, especially tree ferns, significantly increase in abundance in the upper Atokan and lower Desmoinesian. The pattern of change of dominance among Lycosporapellucida, L. granulata, and L, micropapillata in middle Atokan (Westphalian B-C transition) that has been demonstrated earlier in the Illinois basin and eastern Kentucky and Tennessee, also occurs in eastern Kansas. At least 10 species of spores, which appeared in the middle Atokan in other parts of the equatorial coal belt, also appeared at this time in eastern Kansas. Most of these species have their affinities with the ferns, which were adapted to drier habitats than lycopods. Thus, the climate may have become a little drier in the equatorial coal belt during middle Atokan.

Current Research in Earth Sciences↗
USGS2007

Preliminary identification of ground-water nitrate sources using nitrogen and carbon stable isotopes, Kansas

Increasing nitrate-N in ground water is a problem in areas with limited ground-water supplies, such as central Kansas. Nitrate-N concentrations in ground water in the study area in Ellis County range from 0.9 to 26 mg/L. Calculated mean values observed in soil cores are 1.2-15 mg/kg. The ??15N signatures of the ground waters are more enriched (+16.8 to +28.7???) than those of the soils (+8.4 to +1 3.7???), strongly suggesting that nitrate-N sources are not from mineralized and labile nitrogen present in the unsaturated zone. Soil cores were collected near municipal wells to determine if soil nitrogen was a contributing source to the ground water. Increased ??15N of total nitrogen with depth suggests that microbial mineralization processes and possible denitrification or volatilization isotope enrichments have affected the observed ?? 15N signatures in the soil. However, the observed soil-nitrogen values are not of sufficient magnitude to explain the nitrate-N concentrations or associated ??15N values observed in the ground water. Stable carbon isotopes provide some supporting evidence that soils are not a major contributor to the observed nitrate-N concentration in the ground water. ?? 13C values of the dissolved organic carbon (DOC) in soils generally become more enriched with depth while corresponding ground-water ??13C (DOC) values are more depleted than in the overlying soils. Carbon isotope values of the soils are indicative of a C4 plant source that is enriched by microbial processes. The ??13C (DOC) of ground water indicates C3 values that may reflect impacts from animal-waste sources.

Current Research in Earth Sciences↗
USGS2010

Treated wastewater and Nitrate transport beneath irrigated fields near Dodge city, Kansas

Use of secondary-treated municipal wastewater for crop irrigation south of Dodge City, Kansas, where the soils are mainly of silty clay loam texture, has raised a concern that it has resulted in high nitratenitrogen concentrations (10-50 mg/kg) in the soil and deeper vadose zone, and also in the underlying deep (20-45 m) ground water. The goal of this field-monitoring project was to assess how and under what circumstances nitrogen (N) nutrients under cultivated corn that is irrigated with this treated wastewater can reach the deep ground water of the underlying High Plains aquifer, and what can realistically be done to minimize this problem. We collected 15.2-m-deep cores for physical and chemical properties characterization; installed neutron moisture-probe access tubes and suction lysimeters for periodic measurements; sampled area monitoring, irrigation, and domestic wells; performed dye-tracer experiments to examine soil preferential-flow processes through macropores; and obtained climatic, crop, irrigation, and N-application rate records. These data and additional information were used in the comprehensive Root Zone Water Quality Model (RZWQM2) to identify key parameters and processes that influence N losses in the study area. We demonstrated that nitrate-N transport processes result in significant accumulations of N in the thick vadose zone. We also showed that nitrate-N in the underlying ground water is increasing with time and that the source of the nitrate is from the wastewater applications. RZWQM2 simulations indicated that macropore flow is generated particularly during heavy rainfall events, but during our 2005-06 simulations the total macropore flow was only about 3% of precipitation for one of two investigated sites, whereas it was more than 13% for the other site. Our calibrated model for the two wastewater-irrigated study sites indicated that reducing current levels of corn N fertilization by half or more to the level of 170 kg/ha substantially increases N-use efficiency and achieves near-maximum crop yield. Combining such measures with a crop rotation that includes alfalfa should further reduce the amounts of residual N in the soil, as indicated in one of the study sites that had alfalfa in past crop rotations.

Current Research in Earth Sciences↗
USGS2008

Clarification and changes in Permian stratigraphic nomenclature in Kansas

This paper outlines Permian nomenclature changes to Zeller (1968) that have been adopted by the Kansas Geological Survey. The Permian System/ Period, Cisuralian Series/Epoch, and Asselian Stage/Age are established at the base of the Bennett Shale Member of the Red Eagle Limestone. Series/epoch names Wolfcampian, Leonardian, and Guadalupian are retained and usage of Gearyan, Cimarronian, and Custerian is abandoned. The repositioned Carboniferous-Permian boundary divides the Council Grove Group into Carboniferous (Upper Pennsylvanian Series/Epoch; Virgilian Stage/Age) and Permian (Wolfcampian Series Epoch) segments.

Current Research in Earth Sciences↗
USGS2012

History and progress of the North American Soil Geochemical Landscapes Project, 2001-2010

In 2007, the U.S. Geological Survey, the Geological Survey of Canada, and the Mexican Geological Survey initiated a low-density (1 site per 1600 km 2 , 13323 sites) geochemical and mineralogical survey of North American soils (North American Soil Geochemical Landscapes Project). Sampling and analytical protocols were developed at a series of workshops in 20032004 and pilot studies were conducted from 20042007. The ideal sampling protocol at each site includes a sample from 05 cm depth, a composite of the soil A horizon, and a sample from the soil C horizon. The <2-mm fraction of each sample is analyzed for Al, Ca, Fe, K, Mg, Na, S, Ti, Ag, Ba, Be, Bi, Cd, Ce, Co, Cr, Cs, Cu, Ga, In, La, Li, Mn, Mo, Nb, Ni, P, Pb, Rb, Sb, Sc, Sn, Sr, Te, Th, Tl, U, V, W, Y, and Zn by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry following a near-total digestion in a mixture of HCl, HNO 3 , HClO 4 , and HF. Separate methods are used for As, Hg, Se, and total C on this same size fraction. The major mineralogical components are determined by a quantitative X-ray diffraction method. Sampling in the conterminous U.S. was completed in 2010 (c. 4800 sites) with chemical and mineralogical analysis currently underway. In Mexico, approximately 66% of the sampling (871 sites) had been done by the end of 2010 with completion expected in 2012. After completing sampling in the Maritime provinces and portions of other provinces (472 sites, 7.6% of the total), Canada withdrew from the project in 2010. Preliminary results for a swath from the central U.S. to Florida clearly show the effects of soil parent material and climate on the chemical and mineralogical composition of soils. A sample archive will be established and made available for future investigations.

Earth Science Frontiers↗
USGS2013

Differential preservation in the geologic record of intraoceanic arc sedimentary and tectonic processes

Records of ancient intraoceanic arc activity, now preserved in continental suture zones, are commonly used to reconstruct paleogeography and plate motion, and to understand how continental crust is formed, recycled, and maintained through time. However, interpreting tectonic and sedimentary records from ancient terranes after arc–continent collision is complicated by preferential preservation of evidence for some arc processes and loss of evidence for others. In this synthesis we examine what is lost, and what is preserved, in the translation from modern processes to the ancient record of intraoceanic arcs. Composition of accreted arc terranes differs as a function of arc–continent collision geometry. ‘Forward-facing’ collision can accrete an oceanic arc on to either a passive or an active continental margin, with the arc facing the continent and colliding trench- and forearc-side first. In a ‘backward-facing’ collision, involving two subduction zones with similar polarity, the arc collides backarc-first with an active continental margin. The preservation of evidence for contemporary sedimentary and tectonic arc processes in the geologic record depends greatly on how well the various parts of the arc survive collision and orogeny in each case. Preservation of arc terranes likely is biased towards those that were in a state of tectonic accretion for tens of millions of years before collision, rather than tectonic erosion. The prevalence of tectonic erosion in modern intraoceanic arcs implies that valuable records of arc processes are commonly destroyed even before the arc collides with a continent. Arc systems are most likely to undergo tectonic accretion shortly before forward-facing collision with a continent, and thus most forearc and accretionary-prism material in ancient arc terranes likely is temporally biased toward the final stages of arc activity, when sediment flux to the trench was greatest and tectonic accretion prevailed. Collision geometry and tectonic erosion vs. accretion are important controls on the ultimate survival of material from the trench, forearc, arc massif, intra-arc basins, and backarc basins, and thus on how well an ancient arc terrane preserves evidence for tectonic processes such as subduction of aseismic ridges and seamounts, oblique plate convergence, and arc rifting. Forward-facing collision involves substantial recycling, melting, and fractionation of continent-derived material during and after collision, and so produces melts rich in silica and incompatible trace elements. As a result, forward-facing collision can drive the composition of accreted arc crust toward that of average continental crust.

Earth-Science Reviews↗