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Full-Text Articles in Sedimentology

Growth Of Methanogens In The Presence Of Perchlorate Salts: A Study For Possible Life On Mars, John Cale Dec 2016

Growth Of Methanogens In The Presence Of Perchlorate Salts: A Study For Possible Life On Mars, John Cale

Biological Sciences Undergraduate Honors Theses

The Phoenix Lander collected soil samples from Mars, and it detected perchlorate salts in its analysis [1]. As oxidizing agents, perchlorates pose a threat to the hypothesis that there may be microbial life on Mars. Since Mars is very dry, perchlorate may continue to accumulate in the soil. If anaerobic methanogens inhabit Mars, then they must be able to grow in the presence of perchlorate salts. There were four species of methanogens tested in this project. The methanogens were first exposed to small concentrations of calcium perchlorate, and then they were gradually tested at higher concentrations. Growth was measured by …


Sedimentary Petrology Of The Hartshorne Formation, Southeastern Arkoma Basin, Arkansas, Ruizhe Yin Dec 2016

Sedimentary Petrology Of The Hartshorne Formation, Southeastern Arkoma Basin, Arkansas, Ruizhe Yin

Graduate Theses and Dissertations

The Pennsylvanian Hartshorne Sandstone crops out in an east trending belt across central Arkansas immediately north of the Ouachita orogenic belt and south of the Boston Mountains. The unit, composed of massive to cross bedded sandstone ranging to 150m in thickness, was deposited by a west-flowing river system that extended from central Arkansas to southeastern Oklahoma. The source of the sediment has been extensively discussed but not completely established. The object of this thesis is to constrain the source area and terrain based on thin section mineralogy and texture. Thin sections were prepared from outcrops in the Arkoma Basin and …


Examining Denitrification In Agricultural Ditch Sediments Vegetated With Rice Cutgrass (Leersia Oryzoides): Modeling Seasonal Variation Across Increasing Levels Of Nitrate Loading And Model Application To Pre-Existing Datasets, Shannon Lee Speir Dec 2016

Examining Denitrification In Agricultural Ditch Sediments Vegetated With Rice Cutgrass (Leersia Oryzoides): Modeling Seasonal Variation Across Increasing Levels Of Nitrate Loading And Model Application To Pre-Existing Datasets, Shannon Lee Speir

Graduate Theses and Dissertations

Nitrogen (N) derived from fertilizer application in agricultural systems may contribute to significant environmental impacts, including eutrophication of fresh and coastal waters. Rice cutgrass (Leersia oryzoides) can significantly enhance denitrification potential in agricultural ditch sediments, but relationships with known drivers are not well understood. To address this, I examined effects of nitrate (NO3-) availability on dinitrogen gas (N2) and NO3- fluxes seasonally in Chapter 2. Denitrification rates were measured as N2 flux from intact vegetated sediment cores using Membrane Inlet Mass Spectrometry (MIMS). Michaelis-Menten models were developed from observations to mathematically describe N2 fluxes across the spring, summer, and fall …


Stratigraphy And Depositional Environment Of The Middle Atoka Formation, Central Arkoma Basin, Western Arkansas, Yueyang Wang Dec 2016

Stratigraphy And Depositional Environment Of The Middle Atoka Formation, Central Arkoma Basin, Western Arkansas, Yueyang Wang

Graduate Theses and Dissertations

Wire line logs are widely used in analysis of the subsurface stratigraphy of the middle Atoka Formation, Central Arkoma Basin, Western Arkansas. SP log, Gamma ray log, resistivity log and conductivity log provide valuable information to construct cross sections.

The middle Atoka formation is composed of a succession of shale and sandstone alternations with thickness reaching approximately 3000 feet in the study area. It contains several sandstone units which include Morris, Tackett, Areci, Bynum, Casey and Dunn”A” separated by shale intervals. The purpose of this study is to identify these units and predict sequence stratigraphy and depositional environment by constructing …


Early And Middle Atokan Lithostratigraphy And Reservoir Development, Northern Arkoma Basin, Northwestern Arkansas, Matthew Alan Blaylock Aug 2016

Early And Middle Atokan Lithostratigraphy And Reservoir Development, Northern Arkoma Basin, Northwestern Arkansas, Matthew Alan Blaylock

Graduate Theses and Dissertations

The Arkoma Basin is a peripheral foreland arc basin associated with the Ouachita orogenic belt. In Arkansas, the basin is bounded by the Ouachita belt to the south and the Ozark Dome to the north. Sedimentary rocks of early to middle Atokan age are present in the shallow subsurface at the northern margin of the Arkoma Basin in northwestern Arkansas. Sedimentary units of this time interval reflect basinal subsidence, and the transition of the Arkoma Basin from a passive margin shelf to a rapidly evolving foreland arc basin. Sediment sources from the north and east produced a thickened Lower and …


Validation Of N-Star Nitrogen Rate Recommendations And Evaluation Of N-Star Soil Sampling Procedures For Clay Soils In Arkansas, Jarom Thane Davidson Aug 2016

Validation Of N-Star Nitrogen Rate Recommendations And Evaluation Of N-Star Soil Sampling Procedures For Clay Soils In Arkansas, Jarom Thane Davidson

Graduate Theses and Dissertations

The two methods for determining N-fertilizer recommendations for rice (Oryza sativa L.) in Arkansas are the standard N recommendation (SR) based on soil texture, previous crop, and rice cultivar, and the Nitrogen-Soil Test for Rice (N-STaR) which quantifies the potentially mineralizable-N of the soil and provides a site-specific N recommendation. The N-STaR program has recently been developed, and the validation of N-STaR for clay soils is an important step in ensuring that N-STaR predicts correct N-fertilizer rates for rice under a delayed-flood production system. Small-plot trials located across Arkansas compared the N-STaR 95 and 100% relative grain yield (RGY) N …


Statistical Analysis Of Fluvial Channel Belts, Kyle Ryan Spencer May 2016

Statistical Analysis Of Fluvial Channel Belts, Kyle Ryan Spencer

Graduate Theses and Dissertations

As meandering rivers laterally migrate over time, they build channel belts. The accumulation of all previous flow paths creates the channel belt. To better understand these ancient rivers, modern river systems are being mapped to find statistical relationships between current flow path and the channel belt of river systems. It is important to examine a wide range of systems in terms of age, size, and location. The rivers are being mapped using an ImageJ, interpretations from Saucier (1994) and Google Earth. Three channel belt morphologies are mapped for 15 modern channel belts; the width of the river in relation to …


Sedimentation In The Upper Reaches Of Lake Ouachita, J. A. Patton Jan 2016

Sedimentation In The Upper Reaches Of Lake Ouachita, J. A. Patton

Journal of the Arkansas Academy of Science

Lake Ouachita in west-central Arkansas is the largest man-made reservoir in the state. The lake was created by the U.S. Army Corps of Engineers (USACE) in 1953 for the purposes of hydropower, flood control, and recreation. Although Lake Ouachita is widely known for its high water clarity near Blakely Dam, little is known about the volume and ultimate fate of sediments that enter the lake from two primary tributaries: the North and South Forks of the Ouachita River. This project utilized a dual-frequency echo sounding system in combination with geographic information system and statistical analysis to calculate an average post-impoundment …


Early Cementation Of The Short Creek Oolite Member, Boone Formation (Osagean, Lower Mississippian), Northern Arkansas, K. A. Jayne, A. K. Chandler, W. L. Manger Jan 2016

Early Cementation Of The Short Creek Oolite Member, Boone Formation (Osagean, Lower Mississippian), Northern Arkansas, K. A. Jayne, A. K. Chandler, W. L. Manger

Journal of the Arkansas Academy of Science

The Short Creek Oolite is the only formally named member of the Boone Formation in northern Arkansas. It lacks bedding features, and oolith concentrations that would suggest a shoal environment, and it occurs at variable stratigraphic horizons within the upper Boone Formation consistent with episodic deposition as grainflow slurries. As with modern oolite examples, such as Joulters Cays, Bahamas, the Short Creek preserves numerous intraclasts, and at least one large olistolith indicating an early cementation history.


Reservoir Characterization And Depositional System Of The Atokan Grant Sand, Fort Worth Basin, Texas, Victoria Wood Dec 2015

Reservoir Characterization And Depositional System Of The Atokan Grant Sand, Fort Worth Basin, Texas, Victoria Wood

Graduate Theses and Dissertations

The Atokan Grant Sands are a tight gas sand play that would add new reserves to the Fort Worth Basin. The Fort Worth Basin is located in north-central Texas just west of Dallas, Texas. Within the basin, the study area consists of Denton, Wise, Tarrant, and Parker Counties in Texas. The basin is bounded to the north by the Red River Arch, to the west by the Bend Arch, to the south by the Llano uplift, to the east by the Ouachita structural front, and to the northeast by the Muenster Arch. The Grant Sands are approximately 1,500 ft stratigraphically …


Stratigraphic Analysis With Respect To Aggregate Potential In The Duffield Quarry In Gum Log, Arkansas, Brock Evan Langford May 2015

Stratigraphic Analysis With Respect To Aggregate Potential In The Duffield Quarry In Gum Log, Arkansas, Brock Evan Langford

Graduate Theses and Dissertations

The crushed stone mining industry is valued at nearly one billion dollars in Arkansas alone. Physical properties of the rock dictate whether or not an area may be suited for the establishment of an aggregate quarry. The Gum Log quarry located 10 miles northeast of Russellville, Arkansas is geographically well situated near areas in need of aggregate material, as well as physically competent rock. The rock mined in Gum Log is located in the Upper Atoka Formation, a Middle Pennsylvanian aged member of the Arkoma Basin. There are five different lithologic facies identifiable in the quarry (Facies 1-5 respectively): A …


Stratigraphic Characterization And Depositional History Of The Barnett Shale Within The Fort Worth Basin In Denton County, Texas, Matthew Loren Cope May 2015

Stratigraphic Characterization And Depositional History Of The Barnett Shale Within The Fort Worth Basin In Denton County, Texas, Matthew Loren Cope

Graduate Theses and Dissertations

The Barnett shale, located in the Fort Worth Basin, is a geologic unit that has undergone extensive study and currently holds great economic importance. It contains well-known stratigraphy, but still holds questions with regard to the specific stratigraphic variation over much of its area. Denton County contains a large geographic area of the Barnett shale, and holds many answers to the varying stratigraphy of the Barnett shale, as well as an explanation into its depositional history. The investigation involved the use of two cross sections utilizing 32 and 26 wells respectively in the western region of Denton County, Texas. From …


Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock Jan 2015

Habitat Assessment And Ecological Restoration Design For An Unnamed Tributary Of Stone Dam Creek, Conway, Arkansas, Paige E. Boyle, Mary C. Savin, James A. Mccarty, Marty D. Matlock

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Urbanization can lead to increased sedimentation, erosion, pollution, and runoff into streams. The United States Environmental Protection Agency’s (USEPA) Rapid Bioassessment Protocols (RBPs) are sets of guidelines that can be used to assess a habitat’s sedimentology, hydrology, vegetation, and geomorphology to determine impairment. An unnamed tributary of Stone Dam Creek on the University of Central Arkansas (UCA) campus in Conway, Arkansas runs partially underground and through the urbanized UCA campus watershed. The stream was assessed using the USEPA’s RBPs to determine impairment of the stream, and received a RBP score of 71.2 out of 200 compared to 153.5 in a …


Application Of Detrital Zircon Geochronology To Determine The Sedimentary Provenance Of The Middle Bloyd Sandstone, Arkoma Shelf, Northern Arkansas, Greg Michael Buratowski May 2014

Application Of Detrital Zircon Geochronology To Determine The Sedimentary Provenance Of The Middle Bloyd Sandstone, Arkoma Shelf, Northern Arkansas, Greg Michael Buratowski

Graduate Theses and Dissertations

The sedimentary provenance of the middle Bloyd sandstone and subsequent sediment transport and dispersal patterns of the Early Pennsylvanian were interpreted by utilizing U-Pb detrital zircon geochronology. Eight middle Bloyd sandstone samples were analyzed. A total of 855 concordant analyses resulted. Peaks occurred at 350-500 Ma, 950-1200 Ma, 1300-1500 Ma, 1800-2300 Ma, and >2500 Ma. These peaks were determined to represent crystalline source rocks on the Laurentian craton from Acadian-Taconic, Grenville, Midcontinent Granite-Rhyolite, Yavapai-Mazatzal, Paleoproterozoic, and Archean Superior Provinces respectively. Grenville age zircons were the most common zircons identified in the middle Bloyd sandstone samples. The Appalachian Mountain region is …


Sedimentary Provenance Of The Wedington Member, Fayetteville Shale, From Age Relations Of Detrital Zircons, William Tyson Cains Dec 2013

Sedimentary Provenance Of The Wedington Member, Fayetteville Shale, From Age Relations Of Detrital Zircons, William Tyson Cains

Graduate Theses and Dissertations

U-Pb geochronology of detrital zircons collected from the Chesterian Wedington Sandstone allows interpretation of sediment provenance and dispersal patterns in the southern midcontinent during the Late Mississippian. Detrital zircons analyzed from six samples of Wedington Sandstone yielded a final result of 565 concordant analyses used for interpretation. Results are plotted as Probability-Density Plots to interpret the spectrum of ages. Significant peaks occurred at 350-500 Ma, 950-1250 Ma, 1300-1500 Ma, 1600-1800 Ma, 1800-2300 Ma, and >2500 Ma. These peaks are interpreted as sourced by crystalline rocks within the Laurentian craton from Taconic-Acadian, Grenville, Midcontinent Granite-Rhyolite, Yavapai-Mazatzal, Paleoproterozoic, and Superior Provinces. The …


Insights Into The Timing, Origin, And Deformation Of The Highland Mountains Gneiss Dome In Southwestern Montana, Usa, Lane Markes Boyer Aug 2013

Insights Into The Timing, Origin, And Deformation Of The Highland Mountains Gneiss Dome In Southwestern Montana, Usa, Lane Markes Boyer

Graduate Theses and Dissertations

The Highland Mountains of southwestern Montana offer a unique view of the Archean igneous and metamorphic rocks within the Great Falls tectonic zone (GFTZ). A Paleoproterozoic structural gneiss dome has been interpreted in the southern extent of the Highland Mountains. The ∼ 130km2 of exhumed metamorphic rocks and gneiss dome exposed in the Highland Mountains are the primary focus of this research. The formation of the Highland Mountains gneiss dome is proposed to be directly related to a northwest-side down detachment (the Steels Pass shear zone) that formed during terrane collision along the GFTZ. The field investigation determined foliation …


Analysis Of Tripolitic Chert In The Boone Formation (Lower Mississippian, Osagean), Northwest Arkansas And Southwestern Missouri, Paul Marchand Minor Aug 2013

Analysis Of Tripolitic Chert In The Boone Formation (Lower Mississippian, Osagean), Northwest Arkansas And Southwestern Missouri, Paul Marchand Minor

Graduate Theses and Dissertations

The Boone Formation in northwest Arkansas and southwestern Missouri exposes a nearly complete sequence of Lower Mississippian chert-bearing carbonates deposited by a single 3rd order transgression and regression. An abundant amount of chert that has replaced limestone highlights the Boone, but little is understood about the timing and development of chert in Lower Mississippian carbonates. Interpretation of the diagenetic history of the chert, in particular tripolite, has significant implications beyond the outcrop. Determining the origin, timing, and extent of tripolitic chert in the Lower Mississippian System improves reservoir characterization in subsurface petroleum reservoirs in the mid-continent that are laterally equivalent …


Subsurface Stratigraphy And Characterization Of Mississippian (Osagean To Meramecian) Carbonate Reservoirs Of The Northern Anadarko Shelf, North-Central Oklahoma, Brett Robert Wittman May 2013

Subsurface Stratigraphy And Characterization Of Mississippian (Osagean To Meramecian) Carbonate Reservoirs Of The Northern Anadarko Shelf, North-Central Oklahoma, Brett Robert Wittman

Graduate Theses and Dissertations

Mississippian carbonate strata of the midcontinent contain prolific oil and gas reservoirs. Production from these carbonates has been primarily from two reservoir types, the Mississippi "chat" and recently denser chert-rich mudstone intervals. The"chat" interval is a high porosity chert residuum associated with the both the Osagean and basal Pennsylvanian unconformity. The distribution of the "chat" reservoir is discontinuous and heterogeneous. Recent horizontal drilling successes have reinvigorated academic and industry interest in the Lower Mississippian. Much of the activity is now targeting lower porosity, cherty, mudstone intervals of the Reeds Spring and Cowley Formations, which were previously considered to be non-economic. …


Diagenesis And Reservoir Characterization Of The Pennsylvanian Middle Atoka Formation, Sebastian And Logan Counties, West-Central Arkansas, Elvis Chekwube Bello Dec 2012

Diagenesis And Reservoir Characterization Of The Pennsylvanian Middle Atoka Formation, Sebastian And Logan Counties, West-Central Arkansas, Elvis Chekwube Bello

Graduate Theses and Dissertations

The Middle Atoka Formation evolved from a stable passive margin during the early Pennsylvanian time to a rapidly subsiding basin, with the sedimentary fill thickening greatly southward during the middle Pennsylvanian time. The basin dips in north-south direction. An east-west anticlines and synclines were observed.

The purpose of this study is to establish the stratigraphic units, reservoir geometry and distribution, and infer the depositional environments and reservoir quality. Well correlation and petrographic studies are used to achieve the goals.

Sandstone Point Count method was used. The Point Counts was divided into five categories. They include the framework grains (quartz, feldspar, …


Outcrop Investigation Of The Reeds Spring (Boone, Mississippian) Of The Hindsville Quarry Using Terrestrial Lidar, Terryl Glenn Daniels Aug 2012

Outcrop Investigation Of The Reeds Spring (Boone, Mississippian) Of The Hindsville Quarry Using Terrestrial Lidar, Terryl Glenn Daniels

Graduate Theses and Dissertations

In northern Oklahoma and southern Kansas the Reeds Springs Formation (Boone, Mississippian) is a hydrocarbon exploration objective (Mazullo et al, 2011). The Hindsville quarry located in the northeastern portion of Washington County in Arkansas is the focus of this study. The objective of this study is to characterize the Reeds Spring at the Hindsville Quarry. The use of terrestrial light detecting and ranging(LiDAR) is used to assist in the characterization of the quarry.

The unit architecture within the Hindsville Quarry outlines varying transitional periods that give insight into the deposition of the Reeds Springs Formation. There are comparable formations within …


Reservoir Characterization And Outcrop Analog: The Osagean Reeds Spring Formation (Lower Boone), Western Osage And Eastern Kay County, Oklahoma, Taylor Friesenhahn Aug 2012

Reservoir Characterization And Outcrop Analog: The Osagean Reeds Spring Formation (Lower Boone), Western Osage And Eastern Kay County, Oklahoma, Taylor Friesenhahn

Graduate Theses and Dissertations

The Reeds Spring Formation (Osagean) is a member of the Lower Mississippian carbonate series developed on the Cherokee Platform Province of northeastern Oklahoma. On the western flank of the Ozark Dome, these rocks dip in a west-southwest direction into the subsurface where they are oil and gas reservoirs. A series of road cuts and surface exposures are cropped out in the tri-state area of northwest Arkansas, northeastern Oklahoma, and southwestern Missouri. Outcrop characteristics, including an abundant amount of nodular, anastomosing chert, generally finer-grained carbonate texture, and stratigraphic relationships provide an analog for its subsurface counterpart. Based on core description and …


Sequence Stratigraphy And Depositional Systems Of The Mansfield Sand, Upper Atoka Formation, Arkoma Basin, Arkansas, Scott Cherry Aug 2012

Sequence Stratigraphy And Depositional Systems Of The Mansfield Sand, Upper Atoka Formation, Arkoma Basin, Arkansas, Scott Cherry

Graduate Theses and Dissertations

The Mansfield sand is an informally named member of the Pennsylvanian Atoka Formation in Arkansas. Once a productive gas reservoir, the Mansfield is situated in a double plunging anticline in the southern portion of the Arkoma Basin. The formation is internally composed of sandstone units ranging in thickness from tens of feet to over a hundred feet interbedded with shale units ranging in thickness from several tens of feet to hundreds of feet. Previous studies have focused on the stratigraphy of the lower and middle Atoka. A detailed subsurface study of the stratigraphic framework of the Mansfield sand was conducted …


Impact Of Black Shale Weathering On Sediment Quality, G. M. Ogendi, R. E. Hannigan, Jerry L. Farris, D. Smith Jan 2004

Impact Of Black Shale Weathering On Sediment Quality, G. M. Ogendi, R. E. Hannigan, Jerry L. Farris, D. Smith

Journal of the Arkansas Academy of Science

Weathering of black shales leads to elevated metal concentrations in both surface water and stream sediments. In spite of the recent focus on black shales, few data exist on the ecological impacts of this process particularly on aquatic organisms. The key objective of this study was to determine the impact of trace metal concentrations in sediments upon aquatic organisms. To achieve the above objective, stream sediment samples were collected from streams draining black shale and limestone (used as a reference stream) lithologies located in central Arkansas between June 2003 and January 2004. Trace metal concentrations were measured by the dynamic …


Geologic Hazards Associated With Shale Strata And Swelling Clays Within Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss Jan 2001

Geologic Hazards Associated With Shale Strata And Swelling Clays Within Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss

Journal of the Arkansas Academy of Science

No abstract provided.


Reference Sediment Selection In The Lower Mississippi Delta, M. T. Moore, C. D. Milam, Jerry L. Farris Jan 1996

Reference Sediment Selection In The Lower Mississippi Delta, M. T. Moore, C. D. Milam, Jerry L. Farris

Journal of the Arkansas Academy of Science

Floodplain deposition has been a critical part in the evolution of Arkansas' Delta ecoregion, and because ofits high potential for such events, this region is highly enriched and extremely fertile. Historically, water quality in the area has been the subject ofscientific study, and as a result littlehas been published on the effects of underlying sediment with associated benthic communities. Sediment analysis is critical to many of the ongoing aquatic studies because ofits significance as both a habitat for benthic organisms and a sink for contaminants. Seven rivers and one creek within the Delta ecoregion were examined for water chemistry, sediment …


Textural And Lithologic Differences Of Cretaceous, Tertiary, And Quaternary Gravels Of South Arkansas, Lesli Wood Jan 1987

Textural And Lithologic Differences Of Cretaceous, Tertiary, And Quaternary Gravels Of South Arkansas, Lesli Wood

Journal of the Arkansas Academy of Science

Stream gravels have been derived from the Ouachita Mountains since at least Cretaceous times. Past studies have assigned ages to gravel deposits in the basins of the Saline and Little Missouri Rivers on the basis of altitude above local floodplains. This study examines the lithologies and textures of seven gravel outcrops ranging in age from Cretaceous to Quaternary to determine whether any patterns of variation based on assigned ages, variable sources, or precise depositional setting can be discerned. No variation patterns could be found for size distributions of sand-sized and larger fractions. However, the amount of silt-clay matrix decreases through …


Lithostratigraphy Of The Cane Hill Member Of The Hale Formation (Type Morrowan), Northwest Arkansas, Robert T. Liner Jan 1979

Lithostratigraphy Of The Cane Hill Member Of The Hale Formation (Type Morrowan), Northwest Arkansas, Robert T. Liner

Journal of the Arkansas Academy of Science

The Hale Formation (lower Morrowan Series) is a sequence of sandstones and shales divided into the Cane Hill(lower) and Prairie Grove Members. In Washington County, Arkansas, the type Cane Hill consists predominantly of interbedded fine-grained, noncalcareous sandstones and silty shales often with a pebble conglomerate at its base. The member rests unconformably on Chesterian Strata of either the Pitkin Formation or underlying Fayetteville Formation, and it is unconformably overlain by the Prairie Grove Member. In Washington County, the Cane Hill exhibits a slight thickening trend to the south and east. Interpretation of sedimentary structures indicates that the Cane Hill was …


Regional Carbonate Deposition Of The Pitkin Limestone (Chesterian): Washington And Crawford Counties, Arkansas, Robert E. Tehan Jan 1976

Regional Carbonate Deposition Of The Pitkin Limestone (Chesterian): Washington And Crawford Counties, Arkansas, Robert E. Tehan

Journal of the Arkansas Academy of Science

The Pitkin Limestone overlies black shale of the Fayetteville Formation and is the youngest Mississippian unit in the Paleozoic succession of northwest Arkansas. Five major fades have been delineated within the formation by apetrographic examination of samples collected from 17 measured sections: (1) oolith facies, (2) bioclast facies, (3) nodular limestone-shale facies, (4) mudstone facies, and (5) lime mud mound facies. The distribution of these facies in the Pitkin Formation suggests that Fayetteville terrigenous sedimentation was succeeded by the deposition of widespread oolith shoals and skeletal blanket sand bodies across the northern Arkansas structural platform. Sparse accumulations of lime mud …


Algal-Bryozoan Carbonate Buildups Within The Pitkin Limestone (Mississippian-Chesterian), Northwest Arkansas, Alex T. Warmath Jan 1976

Algal-Bryozoan Carbonate Buildups Within The Pitkin Limestone (Mississippian-Chesterian), Northwest Arkansas, Alex T. Warmath

Journal of the Arkansas Academy of Science

More than 14 biohermal buildups have been recognized within the Pitkin Limestone (Mississippian-Chesterian) in eastern Washington and western Madison Counties, northwest Arkansas. These buildups resemble previously described algal mounds in upper Pennsylvanian strata of the Midcontinent region, but differ in their faunal and floral constituents. The mounds are composed of calcilutite with variable amounts of spar and fossil allochemical grains. Associated flanking facies consist of mixed biosparite near the core, grading outward into oosparite. A few zones of shaly, poorly washed biomicrite containing rounded clasts bearing Archimedes fragments are interbedded with the flanking mixed biosparite facies. These clasts appear to …


Relationship Of Lead Mineralization And Bottom Sediment Composition Of Streams, Ponca-Boxley District, Arkansas, William S. Bowen, Kenneth F. Steele Jan 1975

Relationship Of Lead Mineralization And Bottom Sediment Composition Of Streams, Ponca-Boxley District, Arkansas, William S. Bowen, Kenneth F. Steele

Journal of the Arkansas Academy of Science

Samples from tributaries draining known mineralized areas contain considerably more lead than those from the main stream. The unique sediments (i.e. lead rich) from the tributaries are quickly diluted in the main stream to background levels. The lead content of the sediments from the tributaries apparently is controlled by the presence of lead-rich clasts. Sorption of lead by iron oxide coating grains is more significant in the main stream because the unique clasts are diluted. The mineralization also increases zinc and cadmium levels in the sediments. The concentration of calcium is controlled largely by the presence of limestone, whereas the …