Papers by Mark Paul Speeg Krekeler
Delineating affected areas from radiological dispersal device (RDD) events is a major challenge i... more Delineating affected areas from radiological dispersal device (RDD) events is a major challenge in emergency response. Remote sensing is one promising technique for detecting and discriminating dangerous from benign materials over large areas and from a safe distance. Remote sensing spectra of one major threat—cesium chloride (CsCl) powders—identifies previously unrecognized emissivity features at 2.96 m (Ͼ30 percent), 6.01 m (Ͼ20 percent), a broad feature at 7.10-7.49 m (6-8 percent), and a triplet at 8.46 (6 percent), 8.89 (11-15 percent), and 9.33 m (5-7 percent). While the features at 2.96, 6.01, and 7.10-7.49 m are masked by atmospheric gases such as water vapor, the triplet at 8.46, 8.89, and 9.33 m provides a unique spectral fingerprint that can be safely exploited from platforms at standoff distances.
Thesis (PH. D. in Geotechnical Engineering and Geosciences)--University of Illinois at Chicago, 2... more Thesis (PH. D. in Geotechnical Engineering and Geosciences)--University of Illinois at Chicago, 2003. Vita. Includes bibliographical references (leaves 138-146).
Environmental Earth Sciences, 2009
Constructed wetlands can be a low-cost, ecologically based technology to locally treat domestic w... more Constructed wetlands can be a low-cost, ecologically based technology to locally treat domestic wastewater prior to discharge. Wetland systems implemented in the resort village of Akumal in the state of Quintana Roo, in the Yucatan Peninsula of Mexico have been considered moderately successful over approximately 10 years of operation. Yet the wide-scale implementation of constructed wetlands has not occurred in the
Developments in Clay Science, 2011
ABSTRACT The essential features of the palygorskite–sepiolite mineral group are (1) continuous te... more ABSTRACT The essential features of the palygorskite–sepiolite mineral group are (1) continuous tetrahedral basal oxygen planes, (2) an inverted tetrahedral arrangement that forms ribbons of joined pyroxene-like chains, and (3) a discontinuous octahedral sheet. These features are based on palygorskite and sepiolite models only and do not reflect other possible structural variations (e.g. chains that are not pyroxene-like). The palygorskite–sepiolite mineral group (stricto sensu) consists of palygorskite, sepiolite, falcondoite, loughlinite, raite, tuperssuatsiaite, and yofortierite, and probably kalifersite (additional structural data needed). Like most phyllosilicates, the apical oxygen atoms of the palygorskite–sepiolite mineral group complete octahedral coordination with OH (or OH2) around metal cations. The octahedra and attached tetrahedra form a strip or ribbon pattern, and these octahedra and adjacent tetrahedra form a “polysome”.Average octahedral (M) and tetrahedral (T) bond lengths of some micas (e.g., MO: 2.019Å, TO: 1.632Å) and palygorskite (MO: 2.016Å, TO: 1.623Å) suggest that misfit between the lateral dimensions of the tetrahedral sheet and the octahedral strip is not the cause of the polysome structure of palygorskite. To investigate the linkage of the tetrahedra and octahedra, various structure parameters are defined to compare palygorskite–sepiolite group minerals to phyllosilicates.Palygorskite–sepiolite group minerals form in high alkali environments ranging from low-temperature aqueous solutions (e.g. salt lakes) to high-temperature [e.g. agpaitic (Na+K)/Al>1] environments. These environments indicate alkali-rich aqueous conditions at near-surface to hydrothermal (
Active and Passive Signatures, 2010
ABSTRACT A variety of crude oils and refined petroleum products were applied to ten common terres... more ABSTRACT A variety of crude oils and refined petroleum products were applied to ten common terrestrial substrates with the goal of developing a set of representative reflectance spectra for hydrocarbon-substrate combinations. Similar to previous studies, each hydrocarbon darkened the substrates and produced hydrocarbon absorption features near 1200, 1690-1770, and 2270-2400 nm, along with a host of other minor features in the VIS/NIR/SWIR portion of the spectrum. Some substrate absorption features interfered with hydrocarbon absorptions, complicating spectral signatures. The reflectance spectra varied directly with the amount of liquid on the substrate. Liquid-saturated samples were left to age and regularly re-measured, establishing a relationship between evaporative loss for volatile and semivolatile products and sample reflectance. The results outline temporal windows of opportunity and minimum detection thresholds for volatiles. They also provide a means for remotely distinguishing 1) water from petroleum products on some substrates and 2) some similar hydrocarbons from one another based on their volatility.
Active and Passive Signatures II, 2011
ABSTRACT The Deepwater Horizon explosion and subsequent sinking produced the largest oil spill in... more ABSTRACT The Deepwater Horizon explosion and subsequent sinking produced the largest oil spill in U.S. history. One of the most prominent portions of the response is mapping the extent to which oil has reached thousands of miles of shoreline. The most common method of detecting oil remains visual spotting from airframes, supplemented by panchromatic / multispectral aerial photography and satellite imagery. While this imagery provides a synoptic view, it is often ambiguous in its ability to discriminate water from hydrocarbon materials. By employing spectral libraries for material identification and discrimination, imaging spectroscopy supplements traditional imaging techniques by providing specific criteria for more accurate petroleum detection and discrimination from water on terrestrial backgrounds. This paper applies a new hydrocarbon-substrate spectral library to SpecTIR HST-3 airborne imaging spectroscopy data from the Hurricane Katrina disaster in 2005. Using common material identification algorithms, this preliminary analysis demonstrates the applicability and limitations of hyperspectral data to petroleum/water discrimination in certain conditions. The current work is also the first application of the petroleum-substrate library to imaging spectroscopy data and shows potential for monitoring long term impacts of Deepwater Horizon.
Waste Management, 2008
Transmission electron microscopy (TEM) techniques were used to investigate the spent cathodic mat... more Transmission electron microscopy (TEM) techniques were used to investigate the spent cathodic material of a single common brand of disposable alkaline batteries. Mn-oxide particles are anhedral and irregular in shape and compose an estimated 99-95% of the < 10 microm size fraction of sample material. Diameters of particles vary widely and typically are between 50 nm and 3 microm; however, most particles are approximately 200-400 nm in diameter. Chemical composition varies for Mn-oxide particles with concentrations being SiO2 (0.00-1.52 wt%), TiO2 (0.49-4.58 wt%), MnO (65.85-92.06 wt%), ZnO (1.00-7.53 wt%), K2O (4.97-20.48 wt%) and SO3 (0.43-2.21 wt%). Discrete prismatic zinc crystals occur and vary from a maximum of approximately 0.8 microm long x 0.15 microm wide, to 100 nm long x 20 nm wide. Titanium metal was also observed in samples and composes approximately 0.25-1.0% of the < 10 microm size fraction of sample material. Results of this study suggest that battery components may be recycled in some special applications. Examples are low energy-low material requirement products such as paint pigments and Zn nanoparticles. This investigation provides detailed constraints on the nature of spent cathodic materials to improve existing recycling methods and develop new technologies.
Journal of Power Sources, 2012
A count of the type and brand of spent alkaline batteries from a collection program operated by B... more A count of the type and brand of spent alkaline batteries from a collection program operated by Butler County, Ohio was performed to determine the level of brand diversity, to provide estimates of the size of the waste stream, and quantities collected for recycling and for landfilling. The program has a total of 37 school drop off sites at both public and private elementary, middle and high schools. Several additional sites for battery drop include public libraries in the towns of Hamilton, Fairfield, Oxford, two county government administration centers, and two major retail stores in Fairfield and West Chester townships.
Journal of Power Sources, 2011
ABSTRACT The mineralogy of anodic portions of spent alkaline batteries from a leading brand (Dura... more ABSTRACT The mineralogy of anodic portions of spent alkaline batteries from a leading brand (Duracell) that had been equilibrated in ambient air for approximately 4 months was investigated to determine if material generated from this low energy process may be suitable stock material for recycling. Powder X-ray diffraction (XRD) identified the bulk of the ambient air oxidized anodic material as zincite (ZnO). Scanning electron microscopy investigation indicates a variety of textures of zincite are present with euhedral hexagonal prisms being the most common crystal form. Energy dispersive spectroscopy (EDS) analysis indicates that there are no minor amounts of Mn within the zincite. Transmission electron microscopy investigation indicates a variety of textures exist in the <2 μm size fraction including near euhedral prismatic crystals, crystals with step-fashion terminations and indentations, heavily corroded zincite and near amorphous aggregates of anastomozing zinc oxide. Impurities in the <2 μm size fraction include minor amounts of unidentified mixed sulfate materials and are interpreted as dominantly occurring as thin coatings on zincite particles. Discrete submicrometer-sized spherical and rhomboid particles of Zn–Mn oxides are also common impurities in the <2 μm size fraction but occurr at abundance of <1% by volume.This study provides new baseline information that can be used to develop large scale recycling of zincite from spent alkaline batteries. A promising applications of zincite are numerous, including the development of new solar cell materials. The spent alkaline battery waste stream may serve as promising resource for driving further development of this sector of the economy.
Journal of Power Sources, 2012
Journal of Archaeological Science, 2003
The Loyd site is a multicomponent prehistoric homestead located approximately 8 km northeast of C... more The Loyd site is a multicomponent prehistoric homestead located approximately 8 km northeast of Cahokia, the largest Native American chiefdom north of Mexico. The Loyd site was occupied at AD 900 and then again at AD 1285. These occupations are coincident respectively with the beginnings of Cahokia's fluorescence and with the degeneration of its political power. Two Mill Creek chert Ramey knives found within a datable context were cached in one of the Moorehead phase wall trenches. These knives offer a unique insight into the cultural practices of the period. Optical inspection under binocular microscopes show that these knives are coated with two pigment colors. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) were used to identify copper and iron based pigments. Because of the fine craftsmanship, the lack of edgewear, and the occurrence of copper pigment, we interpret the use of these knives as potentially ceremonial in nature.
Environmental Pollution, 2013
Environmental Geology, 2009
A palygorskite unit was discovered in a road cut of undifferentiated Tertiary limestone between t... more A palygorskite unit was discovered in a road cut of undifferentiated Tertiary limestone between the villages of El Pariso and San Roman (18°49.309N, 88°37.861W) in the southeastern Yucatán Peninsula, Mexico. This is the southern most locality of a clay-rich sedimentary unit reported in the literature for the Tertiary carbonates of the Yucatán Peninsula. This occurrence indicates a much wider range of palygorskite-rich clay deposition than previously recognized. The lithology is 99% clay and 1% sand to silt size diagenetic quartz grains. The clay consists of approximately 85% palygorskite, 15% montmorillonite and trace amounts of titanium oxides. EDS analyses on palygorskite are largely consistent with sedimentary palygorskites from other coastal marine settings, however palygorskite has a low total Fe content (average = 0.40 wt% expressed as Fe 2 O 3 ) compared to many other sedimentary palygorskites. Montmorillonite chemical compositions are typical and compared to the palygorskite have substantially higher Fe 2 O 3 concentrations (average = 3.90 wt%). The low percentage of coarse grains in the lithology combined with a high proportion of palygorskite and lack of detrimental trace minerals suggest the deposit is of industrial grade; however, it has limited reserves (6,000 m 3 ). The unit could be potentially used in a wide array of environmental applications which are needed in the region including liners for landfills and constructed wetlands. The unit is in a geographic location which would serve the expanding economy of the region. This resource has the potential to have great impact on the quality of the local environment and the economy of a region under great environmental threat.
Environmental Geology, 2009
The Chesapeake Bay is greatly impacted by numerous pollutants including heavy metals and understa... more The Chesapeake Bay is greatly impacted by numerous pollutants including heavy metals and understanding the controls on the distribution of heavy metals in the watershed is critical to mitigation and remediation efforts in controlling this type of pollution. Clasts from a stormwater catchment basin draining a subdivision near George Mason University, Fairfax VA (38°50.090°N 78°19.204°W) were investigated using X-ray diffraction (XRD), Scanning electron microcopy (SEM) and energy dispersive spectroscopy (EDS) to determine the nature of Mn-oxide coatings and relationship to bound heavy metals. Mn-oxides are poorly crystalline and occur as subhedral to anhedral platy particles and more rarely as euhedral plates. Micronodules are a commonly observed texture. Chemical compositions of coatings are variable with average major constituent concentrations being Mn (33.38 wt%), Fe (11.88 wt%), Si (7.33 wt%), Al (5.03 wt%), and Ba (0.90 wt%). Heavy metals are found in the coatings with Zn being most prevalent, occurring in approximately 58% of analyses with an average concentration of (0.66 wt%). Minor amounts of Co, Ni, Pb, and Cl are observed. Heavy metals and Cl are interpreted as being derived from road pollution. Mn-oxides can serve as a sequestration mechanism for pollution but may also release heavy metals. Field and laboratory observations indicate Mn-oxides occurring on the surface of the clasts can be mechanically mobilized. This is a mechanism for transporting heavy metals into the Chesapeake Bay watershed. Deicing agents may serve as a mechanism to release heavy metals through cation exchange and increased ionic strength. This is the first detailed mineralogical investigation of Mn-oxides and the roles they may play in pollution in the Chesapeake Bay.
Clays and Clay Minerals, 2004
ABSTRACT The sedimentology and mineralogy of a 2.5 m core from a palygorskite deposit of the Mioc... more ABSTRACT The sedimentology and mineralogy of a 2.5 m core from a palygorskite deposit of the Miocene Hawthorne Formation, southern Georgia is described. The lithology involves laminated clay-rich sediment composed of ~90% clay and 10% sand, with six clay-pebble layers present. Sand to pebble-size clasts of phosphate material are common throughout the core. The sand laminations are probably flood-related and the clay-pebble layers are storm deposits, with the pebbles being derived locally from subaerial environments. Phosphate clasts are reworked bone material. The sands are quartz-rich and are subarkosic in composition with average quartz counts of 86.50% and average total feldspar counts of 11.50%. Heavy minerals observed include orthopyroxene, clinopyroxene, amphibole, zircon, rutile, garnet, tourmaline, kyanite, muscovite, biotite, spinels and opaques. Palygorskite fibers dominate the clay-size fraction of the samples and comprise ~80 -90% of sample material with smectite comprising the remainder. Hydroxylapatite comprises ~3% of sediment volume and occurs as individual euhedral hexagonal crystals and as clusters of crystals. Investigation of this core suggests that the palygorskite deposit represents a dynamic system with regular flooding and storm deposition being common. Mineral composition of sands may be useful for stratigraphic correlation of palygorskite deposits in the Apalachicola Embayment. This study supports the general environmental interpretations of previous workers for the palygorskite deposits of southern Georgia, but provides greater detail.
clays and clay minerals, 2005
ABSTRACT The transformation process between palygorskite and smectite was studied by examining th... more ABSTRACT The transformation process between palygorskite and smectite was studied by examining the morphological and structural relationships between these two minerals in an assemblage from the Meigs Member of the Hawthorne Formation, southern Georgia. Studied samples were related to an alteration horizon with a tan clay unit above and a blue clay unit below. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were used to study the mechanism of transformation.From AFM data, both clay units contain euhedral palygorskite fibers. Many fibers are found as parallel intergrowths joined along the [010] direction to form 'raft-like' bundles. Degraded fibers, which are common in the tan clay, have a distinctly segmented morphology, suggesting a dissolution texture. Many of the altered palygorskite fibers in the tan clay exhibit an oriented overgrowth of another mineral phase, presumably smectite, displaying a platy morphology. This latter mineral forms along the length of the palygorskite crystals with an interface parallel to {010} of the palygorskite. The resulting grain structures have an elongate 'wing-like' morphology.Imaging by TEM of tan clay material shows smectite lattice-fringe lines intergrown with 2:1 layer ribbon modules (polysomes) of the palygorskite. These features indicate an epitaxial overgrowth of smectite on palygorskite and illustrate the structural relationship between platy overgrowths on fibers observed in AFM data. The epitaxial relationship is described as {010} [001] palygorskite || {010} [001] smectite. Energy dispersive spectroscopy indicates that the smectite is ferrian montmorillonite. Polysomes of palygorskite fibers involved in these textures commonly vary and polysome widths are consistent with double tetrahedral chains (10.4 Å), triple tetrahedral chains (14.8 Å), quadruple tetrahedral chains (21.7 Å) and quintuple tetrahedral chains (24.5 Å).The transformation of palygorskite to smectite and the resulting intergrowths will cause variations in bulk physical properties of palygorskite-rich clays. The observation of this transformation in natural samples suggests that this transformation mechanism may be responsible for the lower abundance of palygorskite in Mesozoic and older sediments.
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Papers by Mark Paul Speeg Krekeler