Science.gov

Sample records for limestone exploration play

  1. The Mississippian Leadville Limestone Exploration Play, Utah and Colorado-Exploration Techniques and Studies for Independents

    SciTech Connect

    Thomas Chidsey

    2008-09-30

    The Mississippian (late Kinderhookian to early Meramecian) Leadville Limestone is a shallow, open-marine, carbonate-shelf deposit. The Leadville has produced over 53 million barrels (8.4 million m{sup 3}) of oil/condensate from seven fields in the Paradox fold and fault belt of the Paradox Basin, Utah and Colorado. The environmentally sensitive, 7500-square-mile (19,400 km{sup 2}) area that makes up the fold and fault belt is relatively unexplored. Only independent producers operate and continue to hunt for Leadville oil targets in the region. The overall goal of this study is to assist these independents by (1) developing and demonstrating techniques and exploration methods never tried on the Leadville Limestone, (2) targeting areas for exploration, (3) increasing deliverability from new and old Leadville fields through detailed reservoir characterization, (4) reducing exploration costs and risk especially in environmentally sensitive areas, and (5) adding new oil discoveries and reserves. The final results will hopefully reduce exploration costs and risks, especially in environmentally sensitive areas, and add new oil discoveries and reserves. The study consists of three sections: (1) description of lithofacies and diagenetic history of the Leadville at Lisbon field, San Juan County, Utah, (2) methodology and results of a surface geochemical survey conducted over the Lisbon and Lightning Draw Southeast fields (and areas in between) and identification of oil-prone areas using epifluorescence in well cuttings from regional wells, and (3) determination of regional lithofacies, description of modern and outcrop depositional analogs, and estimation of potential oil migration directions (evaluating the middle Paleozoic hydrodynamic pressure regime and water chemistry). Leadville lithofacies at Libon field include open marine (crinoidal banks or shoals and Waulsortian-type buildups), oolitic and peloid shoals, and middle shelf. Rock units with open-marine and restricted

  2. Risk analysis of exploration plays

    SciTech Connect

    Rose, P.R.

    1996-08-01

    The most difficult and crucial decision in petroleum exploration is not which prospect to drill, but rather, which new play to enter. Such a decision, whether ultimately profitable or not, commits the Organization to years of involvement, expenditures of $millions, and hundreds of man-years of effort. Even though uncertainties and risks are high, organizations commonly make the new-play decision in a disjointed, non-analytic, even superficial way. The economic consequences of a bad play choice can be disastrous. Using established principles of prospect risk analysis, modern petroleum exploration organizations routinely assign economic value to individual prospects, but they actually operate via exploration programs in plays and trends. Accordingly, the prospect is the economic unit of exploration, whereas the play is the operational unit. Plays can be successfully analyzed as full-cycle economic risk ventures, however, using many principles of prospect risk analysis. Economic measures such as Expected Present Value, DCFROR, etc. apply equally to plays or prospects. The predicted field-size distribution of the play is analogous to the forecast prospect reserves distribution, Economic truncation applies to both. Variance of play reserves is usually much greater than for prospect reserves. Geologic chance factors such as P{sub reservoir}, P{sub generation}, etc., must be distinguished as independent or shared among prospects in the play, so they should be defined so as to apply equally to the play and to its constituent prospects. They are analogous to multiple objectives on a prospect, and are handled differently in performing the risk analysis.

  3. Risk analysis of exploration plays

    SciTech Connect

    Rose, P.R.

    1996-06-01

    The most difficult and crucial decision in petroleum exploration is not which prospect to drill, but rather, which new play to enter. Such a decision, whether ultimately profitable or not, commits the Organization to years of involvement, expenditures of $millions, and hundreds of man-years of effort. Even though uncertainties and risks are high, organizations commonly make the new-play decision in a disjointed, non-analytic, even superficial way. The economic consequences of a bad play choice can be disastrous. Using established principles of prospect risk analysis, modern petroleum exploration organizations routinely assign economic value to individual prospects, but they actually operate via exploration programs in plays and trends. Accordingly, the prospect is the economic unit of exploration, whereas the play is the operational unit. Plays can be successfully analyzed as full-cycle economic risk ventures, however, using many principles of prospect risk analysis. Economic measures such as Expected Present Value, DCFROR, etc. apply equally to plays or prospects. The predicted field-size distribution of the play is analogous to the forecast prospect reserves distribution. Economic truncation applies to both. Variance of play reserves is usually much greater than for prospect reserves. Geologic chance factors such as P{sub reservoir}, P{sub generation}, etc., must be distinguished as independent or shared among prospects in the play, so they should be defined so as to apply equally to the play and to its constituent prospects. They are analogous to multiple objectives on a prospect, and are handled differently in performing the risk analysis.

  4. Mathematical Situations of Play and Exploration

    ERIC Educational Resources Information Center

    Vogel, Rose

    2013-01-01

    The mathematical situations of play and exploration introduced here have been developed as an empirical research instrument for the longitudinal study "erStMaL" (early Steps in Mathematics Learning). They are designed as situations that allow children and a guiding adult to construct situation-related knowledge in common dialogue…

  5. Playful Invention and Exploration. Final Evaluation Report: Executive Summary

    ERIC Educational Resources Information Center

    St. John; Mark; Carroll, Becky; Helms, Jen; Smith, Anita

    2008-01-01

    PIE (Playful Invention and Exploration) is a unique approach to learning that centers on the use of technology and design challenges to create powerful learning experiences in informal education settings. The Playful Invention and Exploration (PIE) Institute project was funded in 2005 by the National Science Foundation (NSF). Overall, 150…

  6. Contexts of Childhood and Play: Exploring Parental Perceptions

    ERIC Educational Resources Information Center

    Singh, Asha; Gupta, Deepa

    2012-01-01

    The article explores cross-cultural notions of play in childhood among parents based on empirical investigations in two economically diverse residential areas in a metropolis in India. All parents had an unquestionable belief in an epistemic grounding of play in children's lives. However, parents begin to question play timings and children's…

  7. Active Play: Exploring the Influences on Children's School Playground Activities

    ERIC Educational Resources Information Center

    Hyndman, Brendon; Benson, Amanda; Telford, Amanda

    2016-01-01

    Because children spend so much of their time in schools, their playgrounds offer a good setting for promoting active play in young lives. Teachers, instead of considering active play a taxing demand on their busy day, have begun to develop an informal curriculum for it. The authors review the research on children's active play and explores its…

  8. Exploring Language Awareness through Students' Engagement in Language Play

    ERIC Educational Resources Information Center

    Ahn, So-Yeon

    2016-01-01

    The present study explores Korean students' demonstration of language awareness through their engagement in language play. Grounded in the understanding of the relationship between language play and an "engagement with language" (EWL) perspective, this ethnographic and discourse analytic study investigates how Korean students aged 11-15…

  9. Creating a Geologic Play Book for Trenton-Black River Appalachian Basin Exploration

    SciTech Connect

    Douglas G. Patchen; Taury Smith; Ron Riley; Mark Baranoski; David Harris; John Hickman; John Bocan; Michael Hohn

    2005-09-30

    Preliminary isopach and facies maps, combined with a literature review, were used to develop a sequence of basin geometry, architecture and facies development during Cambrian and Ordovician time. The main architectural features--basins, sub basins and platforms--were identified and mapped as their positions shifted with time. This is significant because a better understanding of the control of basin geometry and architecture on the distribution of key facies and on subsequent reservoir development in Ordovician carbonates within the Trenton and Black River is essential for future exploration planning. Good exploration potential is thought to exist along the entire platform margin, where clean grainstones were deposited in skeletal shoals from Indiana thorough Ohio and Ontario into Pennsylvania. The best reservoir facies for the development of hydrothermal dolomites appears to be these clean carbonates. This conclusion is supported by observations taken in existing fields in Indiana, Ontario, Ohio and New York. In contrast, Trenton-Black River production in Kentucky and West Virginia has been from fractured, but non-dolomitized, limestone reservoirs. Facies maps indicate that these limestones were deposited under conditions that led to a higher argillaceous content than the cleaner limestones deposited in higher-energy environments along platform margins. However, even in the broad area of argillaceous limestones, clean limestone buildups have been observed in eastern outcrops and, if present and dolomitized in the subsurface, may provide additional exploration targets. Structure and isopach maps developed as part of the structural and seismic study supported the basin architecture and geometry conclusions, and from them some structural control on the location of architectural features may be inferred. This portion of the study eventually will lead to a determination of the timing relative to fracturing, dolomitization and hydrocarbon charging of reservoirs in the

  10. Exploring children's movement characteristics during virtual reality video game play.

    PubMed

    Levac, Danielle; Pierrynowski, Michael R; Canestraro, Melissa; Gurr, Lindsay; Leonard, Laurean; Neeley, Christyann

    2010-12-01

    There is increasing interest in the use of commercially-available virtual reality video gaming systems within pediatric rehabilitation, yet little is known about the movement characteristics of game play. This study describes quantity and quality of movement during Nintendo Wii and Wii Fit game play, explores differences in these movement characteristics between games and between novice and experienced players, and investigates whether motivation to succeed at the game impacts movement characteristics. Thirty-eight children (aged 7-12) with and without previous game experience played Wii (boxing and tennis) and Wii Fit (ski slalom and soccer heading) games. Force plate data provided center of pressure displacement (quantity) and processed pelvis motion indicated smoothness of pelvic movement (quality). Children rated their motivation to succeed at each game. Movement quantity and quality differed between games (p<.001). Children with previous experience playing Wii Fit games demonstrated greater movement quantity during Wii Fit game play (p<.001); quality of movement did not differ between groups. Motivation to succeed did not influence the relationship between experience and outcomes. Findings enhance clinical understanding of this technology and inform the development of research questions to explore its potential to improve movement skills in children with motor impairments.

  11. The southern Bonaparte Gulf, northwest Australia - New exploration plays

    SciTech Connect

    Dauzacker, M.V.; Durrant, J.M.; France, R. ); Nilsen, T. )

    1990-05-01

    Integration of regional exploration data with new basin model concepts has generated new exploration plays in the offshore area defined as the Southern Bonaparte Gulf. This area represents a unique hydrocarbon habitat significantly different from adjacent areas. Early exploration (seven wells), targeting structural highs, encountered numerous hydrocarbon shows. Of most recent significance, Turtle-1 (1984) targeted a midbasin MS-I high recovering degraded oils in the MS-III section. Turtle-2 (1989) tested an additional 320-m-thick, MS-II onlap, encountering within fractured intervals significant oil and gas influx accompanied by massive lost circulation. Significant live oil (nondegraded) was produced on test despite formation damage inflicted during the 14-day well control period. Within the MS-III section thin incompetent seals and meteoric waters have resulted in small, degraded, low-GOR (gas/oil ratio) oil accumulations. In contrast the MS-II section has competent seals and exhibits high-GOR live oil. In consequence, given suitable models for porosity development, MS-II is highly prospective, indicating new exploratory plays: (1) MS-II fractured, stratigraphic pinch-outs flanking MS-I structures, (2) MS-II stacked turbidites and basin floor fans deposited in salt withdrawal subbasins, (3) MS-II carbonate banks within the subbasin's marginal carbonate complexes, (4) MS-I reefs localized over early salt structures and onlapped by MS-II sediments, and (5) MS-II structural and stratigraphic traps associated with diapiric salt. By virtue of the stratigraphic and structural relationship of MS-U sediments, generally onlapping the flanks of the structural highs originally targeted, these new plays have not been tested in optimal locations. A new phase of exploration specifically targeted at these plays is planned.

  12. Understanding Positive Play: An Exploration of Playing Experiences and Responsible Gambling Practices.

    PubMed

    Wood, Richard T A; Griffiths, Mark D

    2015-12-01

    This study is one of the first to explore in detail the behaviors, attitudes and motivations of players that show no signs of at-risk or problem gambling behavior (so-called 'positive players'). Via an online survey, 1484 positive players were compared with 209 problem players identified using the Lie/Bet screen. The study identified two distinct groups of positive players defined according to their motivations to play and their engagement with responsible gambling (RG) practices. Those positive players that played most frequently employed the most personal RG strategies. Reasons that positive players gave for gambling were focused on leisure (e.g., playing for fun, being entertained, and/or winning a prize). By contrast, problem gamblers were much more focused upon modifying mood states (e.g., excitement, relaxation, depression and playing when bored or upset). The present study also suggests that online gambling is not, by default, inherently riskier than gambling in more traditional ways, as online gambling was the most popular media by which positive players gambled. Furthermore, most positive players reported that it was easier to stick to their limits when playing the National Lottery online compared to traditional retail purchasing of tickets. Problem players were significantly more likely than positive players to gamble with family and friends, suggesting that, contrary to a popular RG message, social play may not be inherently safer than gambling alone. It is proposed that players (generally) may identify more with the term 'positive play' than the term 'RG' which is frequently interpreted as being aimed at people with gambling problems, rather than all players.

  13. Understanding Positive Play: An Exploration of Playing Experiences and Responsible Gambling Practices.

    PubMed

    Wood, Richard T A; Griffiths, Mark D

    2015-12-01

    This study is one of the first to explore in detail the behaviors, attitudes and motivations of players that show no signs of at-risk or problem gambling behavior (so-called 'positive players'). Via an online survey, 1484 positive players were compared with 209 problem players identified using the Lie/Bet screen. The study identified two distinct groups of positive players defined according to their motivations to play and their engagement with responsible gambling (RG) practices. Those positive players that played most frequently employed the most personal RG strategies. Reasons that positive players gave for gambling were focused on leisure (e.g., playing for fun, being entertained, and/or winning a prize). By contrast, problem gamblers were much more focused upon modifying mood states (e.g., excitement, relaxation, depression and playing when bored or upset). The present study also suggests that online gambling is not, by default, inherently riskier than gambling in more traditional ways, as online gambling was the most popular media by which positive players gambled. Furthermore, most positive players reported that it was easier to stick to their limits when playing the National Lottery online compared to traditional retail purchasing of tickets. Problem players were significantly more likely than positive players to gamble with family and friends, suggesting that, contrary to a popular RG message, social play may not be inherently safer than gambling alone. It is proposed that players (generally) may identify more with the term 'positive play' than the term 'RG' which is frequently interpreted as being aimed at people with gambling problems, rather than all players. PMID:25209455

  14. CREATING A GEOLOGIC PLAY BOOK FOR TRENTON-BLACK RIVER APPALACHIAN BASIN EXPLORATION

    SciTech Connect

    Douglas G. Patchen; Katharine Lee Avary; John M. Bocan; Michael Hohn; John B. Hickman; Paul D. Lake; James A. Drahovzal; Christopher D. Laughrey; Jaime Kostelnik; Taury Smith; Ron Riley; Mark Baranoski

    2005-04-01

    The Trenton-Black River Appalachian Basin Research Consortium has made significant progress toward their goal of producing a geologic play book for the Trenton-Black River gas play. The final product will include a resource assessment model of Trenton-Black River reservoirs; possible fairways within which to concentrate further studies and seismic programs; and a model for the origin of Trenton-Black River hydrothermal dolomite reservoirs. All seismic data available to the consortium have been examined. Synthetic seismograms constructed for specific wells have enabled researchers to correlate the tops of 15 stratigraphic units determined from well logs to seismic profiles in New York, Pennsylvania, Ohio, West Virginia and Kentucky. In addition, three surfaces for the area have been depth converted, gridded and mapped. A 16-layer velocity model has been developed to help constrain time-to-depth conversions. Considerable progress was made in fault trend delineation and seismic-stratigraphic correlation within the project area. Isopach maps and a network of gamma-ray cross sections supplemented with core descriptions allowed researchers to more clearly define the architecture of the basin during Middle and Late Ordovician time, the control of basin architecture on carbonate and shale deposition and eventually, the location of reservoirs in Trenton Limestone and Black River Group carbonates. The basin architecture itself may be structurally controlled, and this fault-related structural control along platform margins influenced the formation of hydrothermal dolomite reservoirs in original limestone facies deposited in high energy environments. This resulted in productive trends along the northwest margin of the Trenton platform in Ohio. The continuation of this platform margin into New York should provide further areas with good exploration potential. The focus of the petrographic study shifted from cataloging a broad spectrum of carbonate rocks that occur in the

  15. Limestone Caverns

    ERIC Educational Resources Information Center

    Powell, Richard L.

    1970-01-01

    Describes the origin of limestone caverns, using Mammoth Cave as an example, with particular reference to the importance of groundwater information of caverns, the present condition of groundwater, and how caverns develop within fluctuating groundwater zones. (BR)

  16. Changing the game: exploring infants' participation in early play routines.

    PubMed

    Fantasia, Valentina; Fasulo, Alessandra; Costall, Alan; López, Beatriz

    2014-01-01

    Play has proved to have a central role in children's development, most notably in rule learning (Piaget, 1965; Sutton-Smith, 1979) and negotiation of roles and goals (Garvey, 1974; Bruner et al., 1976). Yet very little research has been done on early play. The present study focuses on early social games, i.e., vocal-kinetic play routines that mothers use to interact with infants from very early on. We explored 3-month-old infants and their mothers performing a routine game first in the usual way, then in two violated conditions: without gestures and without sound. The aim of the study is to investigate infants' participation and expectations in the game and whether this participation is affected by changes in the multimodal format of the game. Infants' facial expressions, gaze, and body movements were coded to measure levels of engagement and affective state across the three conditions. Results showed a significant decrease in Limbs Movements and expressions of Positive Affect, an increase in Gaze Away and in Stunned Expression when the game structure was violated. These results indicate that the violated game conditions were experienced as less engaging, either because of an unexpected break in the established joint routine, or simply because they were weaker versions of the same game. Overall, our results suggest that structured, multimodal play routines may constitute interactional contexts that only work as integrated units of auditory and motor resources, representing early communicative contexts which prepare the ground for later, more complex multimodal interactions, such as verbal exchanges. PMID:24936192

  17. Changing the game: exploring infants' participation in early play routines

    PubMed Central

    Fantasia, Valentina; Fasulo, Alessandra; Costall, Alan; López, Beatriz

    2014-01-01

    Play has proved to have a central role in children's development, most notably in rule learning (Piaget, 1965; Sutton-Smith, 1979) and negotiation of roles and goals (Garvey, 1974; Bruner et al., 1976). Yet very little research has been done on early play. The present study focuses on early social games, i.e., vocal-kinetic play routines that mothers use to interact with infants from very early on. We explored 3-month-old infants and their mothers performing a routine game first in the usual way, then in two violated conditions: without gestures and without sound. The aim of the study is to investigate infants' participation and expectations in the game and whether this participation is affected by changes in the multimodal format of the game. Infants' facial expressions, gaze, and body movements were coded to measure levels of engagement and affective state across the three conditions. Results showed a significant decrease in Limbs Movements and expressions of Positive Affect, an increase in Gaze Away and in Stunned Expression when the game structure was violated. These results indicate that the violated game conditions were experienced as less engaging, either because of an unexpected break in the established joint routine, or simply because they were weaker versions of the same game. Overall, our results suggest that structured, multimodal play routines may constitute interactional contexts that only work as integrated units of auditory and motor resources, representing early communicative contexts which prepare the ground for later, more complex multimodal interactions, such as verbal exchanges. PMID:24936192

  18. Limestone geomorphology

    SciTech Connect

    Trudgill, S.

    1985-01-01

    This book focuses on recent work on geomorphological processes and relates them to established theories of landform development. Special attention is paid to soil processes, marine geomorphology, chemical processes and future work on process-form relationships in the context of dated sequences of cave deposits. There are discussions of limestone landforms and other carbonate rocks, caves, hydrological networks, features of karst, morphometry, and coastal landforms and solution chemistry of limestones.

  19. Exploring Play/Playfulness and Learning in the Adult and Higher Education Classroom

    ERIC Educational Resources Information Center

    Tanis, David J.

    2012-01-01

    Play and playfulness and their role in learning are researched extensively in early childhood education. However, as the child matures into an adult, play and playfulness are given less attention in the teaching and learning process. In adult education, there is very little research about play/playfulness and its significance for learning. Despite…

  20. Does CMC Promote Language Play? Exploring Humor in Two Modalities

    ERIC Educational Resources Information Center

    Vandergriff, Ilona; Fuchs, Carolin

    2009-01-01

    In view of the growing body of research on humor and language play in computer-mediated communication (CMC) which--more than any other medium--has been associated with goofing off, joking, and other nonserious communication, this paper compares spontaneous foreign language play (L2 play) in text-only synchronous computer-mediated versus…

  1. Exploring the Uncanny Valley to Find the Edge of Play

    ERIC Educational Resources Information Center

    Eberle, Scott G.

    2009-01-01

    Play often rewards us with a thrill or a sense of wonder. But, just over the edge of play, uncanny objects like dolls, automata, robots, and realistic animations may become monstrous rather than marvelous. Drawing from diverse sources, literary evidence, psychological and psychoanalytic theory, new insights in neuroscience, marketing literature,…

  2. Parents' Perceptions of Preschool Activities: Exploring Outdoor Play

    ERIC Educational Resources Information Center

    Jayasuriya, Avanthi; Williams, Marcia; Edwards, Todd; Tandon, Pooja

    2016-01-01

    Research Findings: Outdoor play is important for children's health and development, yet many preschool-age children in child care settings do not receive the recommended 60 min/day of outdoor play. Child care providers have previously described parent-related barriers to increasing outdoor playtime, including parents not providing appropriate…

  3. Outcrop Analogue Studies in Geothermal Exploration - Characterization of fault zones in Triassic Muschelkalk limestones of the Upper Rhine Graben

    NASA Astrophysics Data System (ADS)

    Meier, S.; Bauer, J. F.; Philipp, S. L.

    2013-12-01

    The characterization of fault zones is of particular importance in geothermal reservoirs since there may be great effects on fluid flow. Fault zones generally consist of two major hydromechanical units: the fault core and the damage zone, surrounded by the host rock. To improve predictions of fracture system parameters for each unit and resulting estimations of reservoir permeabilities at depths we perform outcrop analogue studies. We analyze Middle Triassic Muschelkalk limestones that form one geothermal reservoir formation in the Upper Rhine Graben (southwest Germany) in quarries on its eastern graben shoulder. We measure the orientations and displacements of various fault zones and characterize the fracture systems within the fault zone units and in the host rock. Our studies show that damage zones are well developed even in smaller fault zones. Their fault cores, however, are narrow compared with that of fault zones with large displacements and comprise brecciated material, clay smear, host rock lenses or zones of mineralization. Based on the field data we use analytical models to estimate the permeabilities of the analyzed fracture systems. Results show increased fracture frequencies in the fault zone damage zones and larger fracture apertures parallel or subparallel to fault zone strike that lead to enhanced permeability compared with other orientations. Mineralized fractures accumulated in this direction in the 'Nussloch'-quarry indicate that these fractures were pathways for fault zone parallel fluid flow in the past. This shows that open fractures with orientations parallel to fault zones may be pathways for fault zone parallel fluid flow in geothermal reservoirs. By contrast, well-developed fault cores may be potential barriers for fluid flow in inactive fault zones. To build numerical models to analyze local stress fields and effects on fracture propagation for different fault zone types and geometries information on rock mechanical properties is

  4. What Play Means to Us: Exploring Children's Perspectives on Play in an English Year 1 Classroom

    ERIC Educational Resources Information Center

    Howe, Sally

    2016-01-01

    Opportunities for play and self-initiated activity, considered to be an important part of children's learning in early childhood settings, diminish as children progress into school. Previous studies suggest that losing time for play/self-initiated activity can impact negatively on children's attitudes to school learning. This article discusses the…

  5. Play.

    ERIC Educational Resources Information Center

    Rogers, Fred; Sharapan, Hedda

    1993-01-01

    Contends that, in childhood, work and play seem to come together. Says that for young children their play is their work, and the more adults encourage children to play, the more they emphasize important lifelong resource. Examines some uses of children's play, making and building, artwork, dramatic play, monsters and superheroes, gun play, and…

  6. Variety in Play: Exploring Photographs by Helen Levitt

    ERIC Educational Resources Information Center

    Ruich, Lawrence J.

    2012-01-01

    Children and burgeoning adolescents' creativity blossom in play-based environments. Likewise, students as active social agents have the opportunity to examine the structures and processes that shape them. The photographic image intimates an aura of credibility, providing the students pause to reflect upon their socialized interactions. These…

  7. Exploring the Concept of Sustainable Development through Role-Playing

    ERIC Educational Resources Information Center

    Buchs, Arnaud; Blanchard, Odile

    2011-01-01

    The concept of sustainable development is used in everyday life by the general public, alongside researchers, institutions, and private companies. Nevertheless, its definition is far from being unequivocal. Clarifying the outline of the concept seems necessary. We have created a role-play for this purpose. Our article aims at depicting its main…

  8. Playing with Porn: Greek Children's Explorations in Pornography

    ERIC Educational Resources Information Center

    Tsaliki, Liza

    2011-01-01

    This article draws on the research findings of the Greek Kids Go Online project and the EU Kids Online I network research on children and online technologies in Europe, funded by the European Commission Safer Internet Programme, 2006-2009. It explores the experiences of young people aged between 9 and 17 with pornographic texts online, and…

  9. Play

    NASA Astrophysics Data System (ADS)

    Harteveld, Casper

    Designing a game with a serious purpose involves considering the worlds of Reality and Meaning yet it is undeniably impossible to create a game without a third world, one that is specifically concerned with what makes a game a game: the play elements. This third world, the world of people like designers and artists, and disciplines as computer science and game design, I call the world of Play and this level is devoted to it. The level starts off with some of the misperceptions people have of play. Unlike some may think, we play all the time, even when we grow old—this was also very noticeable in designing the game Levee Patroller as the team exhibited very playful behavior at many occasions. From there, I go into the aspects that characterize this world. The first concerns the goal of the game. This relates to the objectives people have to achieve within the game. This is constituted by the second aspect: the gameplay. Taking actions and facing challenges is subsequently constituted by a gameworld, which concerns the third aspect. And all of it is not possible without the fourth and final aspect, the type of technology that creates and facilitates the game. The four aspects together make up a “game concept” and from this world such a concept can be judged on the basis of three closely interrelated criteria: engagement, immersion, and fun.

  10. Exploring Kindergarten Teachers' Views and Roles Regarding Children's Outdoor Play Environments in Oman

    ERIC Educational Resources Information Center

    Ihmeideh, Fathi M.; Al-Qaryouti, Ibrahim A.

    2016-01-01

    The purpose of this study was to explore kindergarten teachers' views and roles regarding outdoor play environments in Omani kindergartens. Thirty kindergarten teachers from 15 private kindergartens were observed and interviewed. The results indicated that teachers recognize the importance of outdoor play in children's development and learning.…

  11. Exploring the links between personality traits and motivations to play online games.

    PubMed

    Park, Jowon; Song, Yosep; Teng, Ching-I

    2011-12-01

    The present study explores the links between personality traits and motivations to play online games. We identified the underlying dimensions of motivations to play online games, examined how personality traits predict motivation, and investigated how personality traits predict online gaming behavior (i.e., playing time and preference for game genres). Factor analyses identified five motivational factors: relationships, adventure, escapism, relaxation, and achievement. The regression analyses indicated that two personality traits, extraversion and agreeableness, predicted various motivations; however, personality traits did not affect the playing time and game genre preference.

  12. The Ethanol Project: Exploring Alternative Energy with Role-Play and Writing

    ERIC Educational Resources Information Center

    Winter, Julia

    2013-01-01

    This article describes a project that includes a two-week series of researching, essay writing, and speaking lessons exploring the broader implications of using ethanol as a fuel. The author, a chemistry teacher, describes how she uses a senate hearing discussion of ethanol fuel subsidies as the forum for a role-play. The four components of the…

  13. Play-Based Interview Methods for Exploring Young Children's Perspectives on Inclusion

    ERIC Educational Resources Information Center

    Koller, Donna; San Juan, Valerie

    2015-01-01

    Inclusive education provides learning opportunities for children with disabilities in regular settings with other children. Despite the prevalence of inclusive education, few qualitative studies have adequately explored young children's perspectives on inclusion. This paper reviews the findings of a preliminary qualitative study where play-based…

  14. Exploring Game Experiences and Game Leadership in Massively Multiplayer Online Role-Playing Games

    ERIC Educational Resources Information Center

    Jang, YeiBeech; Ryu, SeoungHo

    2011-01-01

    This study explored the in-game experiences of massively multiplayer online role-playing game (MMORPG) players focusing on game leadership and offline leadership. MMORPGs have enormous potential to provide gameplayers with rich social experiences through various interactions along with social activities such as joining a game community, team play…

  15. Play-fairway analysis for geothermal exploration: Examples from the Great Basin, western USA

    SciTech Connect

    Siler, Drew L; Faulds, James E

    2013-10-27

    Elevated permeability within fault systems provides pathways for circulation of geothermal fluids. Future geothermal development depends on precise and accurate location of such fluid flow pathways in order to both accurately assess geothermal resource potential and increase drilling success rates. The collocation of geologic characteristics that promote permeability in a given geothermal system define the geothermal ‘fairway’, the location(s) where upflow zones are probable and where exploration efforts including drilling should be focused. We define the geothermal fairway as the collocation of 1) fault zones that are ideally oriented for slip or dilation under ambient stress conditions, 2) areas with a high spatial density of fault intersections, and 3) lithologies capable of supporting dense interconnected fracture networks. Areas in which these characteristics are concomitant with both elevated temperature and fluids are probable upflow zones where economic-scale, sustainable temperatures and flow rates are most likely to occur. Employing a variety of surface and subsurface data sets, we test this ‘play-fairway’ exploration methodology on two Great Basin geothermal systems, the actively producing Brady’s geothermal system and a ‘greenfield’ geothermal prospect at Astor Pass, NV. These analyses, based on 3D structural and stratigraphic framework models, reveal subsurface characteristics about each system, well beyond the scope of standard exploration methods. At Brady’s, the geothermal fairways we define correlate well with successful production wells and pinpoint several drilling targets for maintaining or expanding production in the field. In addition, hot-dry wells within the Brady’s geothermal field lie outside our defined geothermal fairways. At Astor Pass, our play-fairway analysis provides for a data-based conceptual model of fluid flow within the geothermal system and indicates several targets for exploration drilling.

  16. Exploring the Impact of Role-Playing on Peer Feedback in an Online Case-Based Learning Activity

    ERIC Educational Resources Information Center

    Ching, Yu-Hui

    2014-01-01

    This study explored the impact of role-playing on the quality of peer feedback and learners' perception of this strategy in a case-based learning activity with VoiceThread in an online course. The findings revealed potential positive impact of role-playing on learners' generation of constructive feedback as role-playing was associated…

  17. Playing with Shadows--Playing with Words: Exploring Teachers' Ownership through Poetic Inquiry in a Norwegian-Nepalese Preschool Teacher Education Project

    ERIC Educational Resources Information Center

    Mjanger, Ruth

    2014-01-01

    This article explores the use of poetic inquiry in a transnational competence-building Shadow Play Project. Based on journals from four Nepalese preschool teacher educators, I present and interpret examples of data poems that portray the teachers' experiences of ownership in the project. My discussion intends to make explicit some aspects of the…

  18. Natural fracture characterization: A key to success in an exploration play, Converse County, Wyoming

    SciTech Connect

    Parks, S.L.; Gale, M.S.; Bradley, P.J.; Mount, V.S.

    1996-06-01

    Numerous vertical wells drilled in the southern Powder River basin have encountered fractured, tight, overpressured, Cretaceous hydrocarbon reservoirs. These reservoirs demonstrate enhanced productivity and ultimate recovery with little to no water production. Effective exploration and development of these reservoirs includes a systematic approach to characterization and prediction of the fracture system. Surface mapping within Cretaceous units along the southern and western margins of the basin revealed multiple fracture sets related to both regional and local tectonic events. A pre-Laramide regional fracture set oriented at approximately N70{degrees}E is dominant over the mapped 500 square mile area. This set displays a consistent frequency, direction, height. and morphology both in the surface and subsurface. Fractures in early Tertiary rocks within the basin are unidirectionally oriented along a WNW azimuth, a direction also found in the Cretaceous units. Vaster Resources, Inc. is actively exploring fractured reservoirs in the Powder River basin with horizontal wells targeting the Niobrara and Frontier formations. Integration of the detailed surface outcrop studies with regional cross-sections, Landsat lineament analysis, FMS log data, 2D multicomponent/multisource shear wave seismic, and borehole breakouts (to determine present day stress) have been used to successfully predict the orientation, frequency, and degree of openness of the subsurface fracture system. The consistency of the fracture system and its positive impact on reservoir productivity significantly enhance the prospectiveness of Cretaceous plays throughout the southern Powder River basin.

  19. Pressing an Ear Against a Hive or New Play Explorations in the Twenty-First Century.

    ERIC Educational Resources Information Center

    Bly, Mark

    2003-01-01

    Describes a drama course, which included 20 play readings and discussions as well as descriptive commentary focusing on the play's inherent strengths and the laws which govern the world of the play. Explains how, when reading a certain student play, many of those present grew impatient with the play's alleged inaccessibility. Contends that…

  20. CREATING A GEOLOGIC PLAY BOOK FOR TRENTON-BLACK RIVER APPALACHIAN BASIN EXPLORATION

    SciTech Connect

    Douglas G. Patchen; James Drahovzal; Larry Wickstrom; Taury Smith; Chris Laughery; Katharine Lee Avary

    2004-04-01

    Private- and public-sector stakeholders formed the new ''Trenton-Black River Appalachian Basin Exploration Consortium'' and began a two-year research effort that will lead to a play book for Trenton-Black River exploration throughout the Appalachian basin. The final membership of the Consortium includes 17 gas exploration companies and 6 research team members, including the state geological surveys in Kentucky, Ohio, Pennsylvania and West Virginia, the New York State Museum Institute and West Virginia University. Seven integrated research tasks are being conducted by basin-wide research teams organized from this large pool of experienced professionals. More than 3400 miles of Appalachian basin digital seismic data have been quality checked. In addition, inquiries have been made regarding the availability of additional seismic data from government and industry partners in the consortium. Interpretations of the seismic data have begun. Error checking is being performed by mapping the time to various prominent reflecting horizons, and analyzing for any anomalies. A regional geological velocity model is being created to make time-to-depth conversions. Members of the stratigraphy task team compiled a generalized, basin-wide correlation chart, began the process of scanning geophysical logs and laid out lines for 16 regional cross sections. Two preliminary cross sections were constructed, a database of all available Trenton-Black River cores was created, and a basin-wide map showing these core locations was produced. Two cores were examined, described and photographed in detail, and were correlated to the network of geophysical logs. Members of the petrology team began the process of determining the original distribution of porous and permeable facies within a sequence stratigraphic framework. A detailed sedimentologic and petrographic study of the Union Furnace road cut in central Pennsylvania was completed. This effort will facilitate the calibration of subsurface core

  1. Exploring Hispanic Teacher Candidates' Beliefs about the Value of Play in Children's Learning and Development

    ERIC Educational Resources Information Center

    Cortez-Castro, Diana H.

    2015-01-01

    Play has been globally recognized as valuable to children's learning and development (Frost et al., 2012). The value of play is acknowledged as a developmentally appropriate practice in part because it fosters cognitive, physical, emotional, and social benefits to children. Play is also known as a human right that should be protected. However, in…

  2. Exploring the Potential of Role Play in Higher Education: Development of a Typology and Teacher Guidelines

    ERIC Educational Resources Information Center

    Rao, Deepa; Stupans, Ieva

    2012-01-01

    Role-play, in which learners act out roles in case scenarios, appears to be used across a broad range of discipline areas to address learning across the cognitive, psychomotor and affective domains. This paper describes the development of a prospective typology of role-play learning opportunities derived from role-play scenarios used at one large…

  3. CREATING A GEOLOGIC PLAY BOOK FOR TRENTON-BLACK RIVER APPALACHIAN BASIN EXPLORATION

    SciTech Connect

    Douglas G. Patchen; Chris Laughrey; Jaime Kostelnik; James Drahovzal; John B. Hickman; Paul D. Lake; John Bocan; Larry Wickstrom; Taury Smith; Katharine Lee Avary

    2004-10-01

    The ''Trenton-Black River Appalachian Basin Exploration Consortium'' has reached the mid-point in a two-year research effort to produce a play book for Trenton-Black River exploration. The final membership of the Consortium includes 17 exploration and production companies and 6 research team members, including four state geological surveys, the New York State Museum Institute and West Virginia University. Seven integrated research tasks and one administrative and technology transfer task are being conducted basin-wide by research teams organized from this large pool of experienced professionals. All seismic data available to the consortium have been examined at least once. Synthetic seismograms constructed for specific wells have enabled researchers to correlate the tops of 10 stratigraphic units determined from well logs to seismic profiles in New York and Pennsylvania. In addition, three surfaces in that area have been depth converted, gridded and mapped. In the Kentucky-Ohio-West Virginia portion of the study area, a velocity model has been developed to help constrain time-to-depth conversions. Fifteen formation tops have been identified on seismic in that area. Preliminary conclusions based on the available seismic data do not support the extension of the Rome Trough into New York state. Members of the stratigraphy task team measured, described and photographed numerous cores from throughout the basin, and tied these data back to their network of geophysical log cross sections. Geophysical logs were scanned in raster files for use in detailed well examination and construction of cross sections. Logs on these cross sections that are only in raster format are being converted to vector format for final cross section displays. The petrology team measured and sampled one classic outcrop in Pennsylvania and ten cores in four states. More than 600 thin sections were prepared from samples in those four states. A seven-step procedure is being used to analyze all thin

  4. Outdoor Play and Play Equipment.

    ERIC Educational Resources Information Center

    Naylor, Heather

    1985-01-01

    Discusses aspects of the play environment and its effect on children's play behavior. Indoor and outdoor play spaces are considered along with factors affecting the use of outdoor environments for play. Children's preferences for different outdoor play environments and for various play structures are explored. Guides for choosing play equipment…

  5. Exploring Natural Pedagogy in Play with Preschoolers: Cues Parents Use and Relations among Them

    ERIC Educational Resources Information Center

    Sage, Kara; Baldwin, Dare

    2012-01-01

    Recent developmental work demonstrates a range of effects of pedagogical cues on childhood learning. The present work investigates natural pedagogy in informal parent-child play. Preschool-aged children participated in free play and a toy task with a parent in addition to a toy task with an experimenter. Sessions were extensively coded for use of…

  6. What Students Need: Exploring Teachers' Views via Imagined Role-Playing

    ERIC Educational Resources Information Center

    Zazkis, Rina; Nejad, Masomeh Jamshid

    2014-01-01

    Role-playing is an unscripted dramatic technique that encourages participants to improvise behaviors that illustrate expected actions of persons involved in defined situations. However, among various uses in developing professionals, the use of role-playing in teacher education is rather rare. To give all students the opportunity to participate in…

  7. Exploring the Game of "Julirde": A Mathematical-Educational Game Played by Fulbe Children in Cameroon.

    ERIC Educational Resources Information Center

    Gerdes, Paulus

    2001-01-01

    Presents an educational mathematical activity from Africa. Shows how one child explored the game of Julirde, a game of the mosque emphasizing problem solving and symmetry. Offers several suggestions for exploring the game from the central African country of Cameroon in the elementary school mathematics classroom. (ASK)

  8. An Ecological Exploration of Young Children's Digital Play: Framing Children's Social Experiences with Technologies in Early Childhood

    ERIC Educational Resources Information Center

    Arnott, Lorna

    2016-01-01

    This article outlines an ecological framework for describing children's social experiences during digital play. It presents evidence from a study that explored how 3- to 5-year-old children negotiated their social experiences as they used technologies in preschool. Utilising a systematic and iterative cycle of data collection and analysis,…

  9. Servant Leadership: How does NASA Serve the Interests of Humankind in Aerospace Exploration and the Role STEM Plays in it?

    NASA Technical Reports Server (NTRS)

    Miranda, Felix A.

    2013-01-01

    This presentation provides a description of technology efforts illustrative of NASA Glenn Research Center Core competencies and which exemplifies how NASA serves the interest of humankind in aerospace exploration. Examples are provided as talking points to illustrate the role that career paths in science, technology, engineering and mathematics (STEM) plays in the aforementioned endeavor.

  10. Keeping It Real: Exploring an Interdisciplinary Breaking Bad News Role-Play as an Integrative Learning Opportunity

    ERIC Educational Resources Information Center

    Sweeney, Catherine; O'Sullivan, Eleanor; McCarthy, Marian

    2015-01-01

    Palliative care is a complex area of healthcare best delivered by an interdisciplinary team approach. Breaking bad news is an inherent part of caring for people with life-limiting conditions. This study aims to explore an interdisciplinary breaking bad news role-play in a palliative care module. Participants were undergraduate medical and nursing…

  11. Exploring children's seasonal play to promote active lifestyles in Auckland, New Zealand.

    PubMed

    Ergler, Christina R; Kearns, Robin; Witten, Karen

    2016-09-01

    Studies of seasonal barriers for outdoor activities seldom view families' play practices as grounded in the everyday experience of the natural elements. This paper brings 20 families' mundane outdoor play experiences in Auckland's temperate climate to the fore. Through drawings and interviews, families residing in both suburban detached houses and central city apartments revealed locally constituted beliefs about appropriate play spaces (e.g. garden, park). While the majority of participants retreated to indoor activities during winter, some children and their parents viewed the outdoors as the only opportunity for 'real fun'. We advocate the importance of a better understanding of children's seasonal outdoor play. In particular, we argue that in order to promote year-round healthy levels of outdoor activities it is necessary to understand variations in societal, neighbourhood and family values attributed to outdoor activities. Further, to develop a more nuanced understanding of the locational complexities of outdoor play it is important to understand the meanings of, and practices associated with, seasonal and weather conditions in different international locations. PMID:27572547

  12. Play as a Resource for Children Facing Adversity: An Exploration of Indicative Case Studies

    ERIC Educational Resources Information Center

    Fearn, Maggie; Howard, Justine

    2012-01-01

    In this paper, we suggest that the ability and opportunity to play affords children a natural resource to meet intellectual and emotional challenge. Analysis of case studies focusing on interventions with children caught in the bombing of Beirut, children abandoned to the state system in Romania, and the street children in Rio de Janeiro and Cali…

  13. Trading Spaces: An Educator's Ethnographic Exploration of Adolescents' Digital Role-Play

    ERIC Educational Resources Information Center

    Haynes-Moore, Stacy

    2015-01-01

    In this work, the author examines a digital role-play in which participants composed an alternate version of "The Hunger Games" (Collins, 2008). Participants imagined characters and posted more than 400 scenes in the online collaboration. The author draws upon ethnographic methods (Merriam, 2009) to describe her participant-observer…

  14. Exploring Performativity and Resistance in Qualitative Research Interviews: A Play in Four Acts

    ERIC Educational Resources Information Center

    Beaunae, Cathrine; Wu, Chiu-Hui; Koro-Ljungberg, Mirka

    2011-01-01

    This play describes how the authors become aware of the complexities of resistance and performativity in the qualitative interview process. It also illustrates how this awareness and subsequent acquisition of knowledge changed and informed the way they viewed qualitative research interviewing. More specifically, performativity is put into work in…

  15. More than Child's Play: North Carolina Professor Explores the History of Dolls and Their Sociological Impact

    ERIC Educational Resources Information Center

    Yates, Eleanor Lee

    2004-01-01

    For Dr. Sabrina Thomas, dolls are not just child's play. In fact, they are the subject of her research, which recently landed her a $40,000 grant from the National Endowment for the Humanities. Thomas, an assistant professor of family and consumer sciences at North Carolina Central University, was awarded the grant to write a book on the history…

  16. Why Do We Play the Games? Exploring Institutional and Political Motivations

    ERIC Educational Resources Information Center

    Bardon, Thibaut; Josserand, Emmanuel

    2009-01-01

    Purpose: The purpose of this paper is to explore why digital games based learning (DGBL) is spreading rapidly in all educational settings, when the literature does not provide clear empirical evidence of the pedagogical benefits. The paper seeks to understand why DGBL is constantly developing despite this lack of consensus about the learning…

  17. Precambrian Chuar source rock play: An exploration case history in southern Utah

    SciTech Connect

    Uphoff, T.L.

    1997-01-01

    Source rock potential of the Upper Proterozoic Chuar Group, specifically the Walcott Member of the Kwagunt Formation, provides the basis for a petroleum play in southern Utah. Analyses of Chuar black shales from outcrops in the Grand Canyon show total organic carbon values of 3-9%, hydrogen indices up to 255, and maximum maturity within the oil window. Modeling indicates a potential 150 mi{sup 2} (400 km{sup 2}) area with a minimum generative potential of 2700 MBO{sup *}. Chuar source rocks are proposed as one part of a petroleum system that includes reservoirs in the Cambrian Tapeats Sandstone and seal in the overlying Bright Angel Shale. Prospective structures include anticlines of Laramide age not drilled through the Tapeats interval. One such structure is the Circle Cliffs uplift, which exhibits an area under closure of 9000 mi{sup 2} (2300 km{sup 2}) at the top of the Devonian. In 1994, BHP Petroleum drilled the 28-1 Federal well on the Circle Cliffs structure. The well logged 142 ft (43 m) of Tapeats porosity (>7%) and flowed CO{sub 2} gas at rates up to 5.0 Mcf{sup *} per day. Analysis of bitumen in the reservoir indicated an earlier hydrocarbon charge and suggested a new oil type for the region.

  18. Foraging errors play a role in resource exploration by bumble bees (Bombus terrrestris).

    PubMed

    Evans, Lisa J; Raine, Nigel E

    2014-06-01

    If the cognitive performance of animals reflects their particular ecological requirements, how can we explain appreciable variation in learning ability amongst closely related individuals (e.g. foraging workers within a bumble bee colony)? One possibility is that apparent 'errors' in a learning task actually represent an alternative foraging strategy. In this study we investigate the potential relationship between foraging 'errors' and foraging success among bumble bee (Bombus terrestris) workers. Individual foragers were trained to choose yellow, rewarded flowers and ignore blue, unrewarded flowers. We recorded the number of errors (visits to unrewarded flowers) each bee made during training, then tested them to determine how quickly they discovered a more profitable food source (either familiar blue flowers, or novel green flowers). We found that error prone bees discovered the novel food source significantly faster than accurate bees. Furthermore, we demonstrate that the time taken to discover the novel, more profitable, food source is positively correlated with foraging success. These results suggest that foraging errors are part of an 'exploration' foraging strategy, which could be advantageous in changeable foraging environments. This could explain the observed variation in learning performance amongst foragers within social insect colonies.

  19. High temperature H{sub 2}S removal using limestones

    SciTech Connect

    Cairns, E.J.; Lynn, S.

    1995-12-31

    This project is exploring the technical and economic feasibility of using limestone in a high determine process for cleaning coal gas prior to combustion in a gas turbine. In one version of the process the coal gas would pass counter-currently through a nearly-isothermal, moving bed of limestone that would serve to remove particulates (by filtration), and hydrogen sulfide (by chemisorption), and ammonia (by catalysis). Alternative process configurations include the use of limestone in a cocurrently moving bed, in a fluidized bed, or in an entrained flow sorption system. The objectives of this research have been to define the range of temperatures at which these goals can best be realized at a given pressure, to determine the effect of the magnesium content of the limestone on sulfidation kinetics and calcium utilization, to use the kinetic data to model the various types of sorption systems, and to develop a process for converting calcium sulfide to elemental sulfur and calcium carbonate.

  20. Language Play.

    ERIC Educational Resources Information Center

    Schwartz, Judy I.

    This paper discusses kinds and characteristics of language play, explores the relationship of such play to wider domains of language and play, and speculates on the possible contributions of language play for language mastery and cognitive development. Jump rope chants and ritual insults ("Off my case, potato face") and other expressive language…

  1. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially... classifying of naturally occurring limestone. (b) The ingredient meets the specifications of the...

  2. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially... classifying of naturally occurring limestone. (b) The ingredient meets the specifications of the...

  3. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent... occurring limestone. (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed....

  4. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially... classifying of naturally occurring limestone. (b) The ingredient meets the specifications of the...

  5. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially... classifying of naturally occurring limestone. (b) The ingredient meets the specifications of the...

  6. Basin center - fractured source rock plays within tectonically segmented foreland (back-arc) basins: Targets for future exploration

    SciTech Connect

    Weimer, R.J.

    1994-09-01

    Production from fractured reservoirs has long been an industry target, but interest in this type play has increased recently because of new concepts and technology, especially horizontal drilling. Early petroleum exploration programs searched for fractured reservoirs from shale, tight sandstones, carbonates, or basement in anticlinal or fault traps, without particular attention to source rocks. Foreland basins are some of the best oil-generating basins in the world because of their rich source rocks. Examples are the Persian Gulf basin, the Alberta basin and Athabasca tar sands, and the eastern Venezuela basin and Orinoco tar sands. Examples of Cretaceous producers are the wrench-faulted La Paz-Mara anticlinal fields, Maracaibo basin, Venezuela; the active Austin Chalk play in an extensional area on the north flank of the Gulf of Mexico continental margin basin; and the Niobrara Chalk and Pierre Shale plays of the central Rocky Mountains, United States. These latter plays are characteristic of a foreland basin fragmented into intermontane basins by the Laramide orogeny. The Florence field, Colorado, discovered in 1862, and the Silo field, Wyoming, discovered in 1980, are used as models for current prospecting and will be described in detail. The technologies applied to fracture-source rock plays are refined surface and subsurface mapping from new log suites, including resistivity mapping; 3D-3C seismic, gravity, and aeromagnetic mapping; borehole path seismic mapping associated with horizontal drilling; fracture mapping with the Formation MicroScanner and other logging tools; measurements while drilling and other drilling and completion techniques; surface geochemistry to locate microseeps; and local and regional lineament discrimination.

  7. Scaling on a limestone flooring

    NASA Astrophysics Data System (ADS)

    Carmona-Quiroga, P. M.; Blanco-Varela, M. T.; Martínez-Ramírez, S.

    2012-04-01

    Natural stone can be use on nearly every surface, inside and outside buildings, but decay is more commonly reported from the ones exposed to outdoor aggressively conditions. This study instead, is an example of limestone weathering of uncertain origin in the interior of a residential building. The stone, used as flooring, started to exhibit loss of material in the form of scaling. These damages were observed before the building, localized in the South of Spain (Málaga), was inhabited. Moreover, according to the company the limestone satisfies the following European standards UNE-EN 1341: 2002, UNE-EN 1343: 2003; UNE-EN 12058: 2004 for floorings. Under these circumstances the main objective of this study was to assess the causes of this phenomenon. For this reason the composition of the mortar was determined and the stone was characterized from a mineralogical and petrological point of view. The last material, which is a fossiliferous limestone from Egypt with natural fissure lines, is mainly composed of calcite, being quartz, kaolinite and apatite minor phases. Moreover, under different spectroscopic and microscopic techniques (FTIR, micro-Raman, SEM-EDX, etc) samples of the weathered, taken directly from the buildings, and unweathered limestone tiles were examined and a new mineralogical phase, trona, was identified at scaled areas which are connected with the natural veins of the stone. In fact, through BSE-mapping the presence of sodium has been detected in these veins. This soluble sodium carbonate would was dissolved in the natural waters from which limestone was precipitated and would migrate with the ascendant capilar humidity and crystallized near the surface of the stone starting the scaling phenomenon which in historic masonry could be very damaging. Therefore, the weathering of the limestone would be related with the hygroscopic behaviour of this salt, but not with the constructive methods used. This makes the limestone unable to be used on restoration

  8. Using Cross-Cultural, Intergenerational Play Narratives to Explore Issues of Social Justice and Equity in Discourse on Children's Play

    ERIC Educational Resources Information Center

    Shimpi, Priya Mariana; Nicholson, Julie

    2014-01-01

    Discussion of children's play in international and diverse communities requires careful consideration of social, cultural and political contexts impacting children's lives, as well as recognition of the complexities revealed when these variables are identified and analysed. Using diverse conceptual frameworks represented in the research…

  9. Paleozoic Hydrocarbon-Seep Limestones

    NASA Astrophysics Data System (ADS)

    Peckmann, J.

    2007-12-01

    To date, five Paleozoic hydrocarbon-seep limestones have been recognized based on carbonate fabrics, associated fauna, and stable carbon isotopes. These are the Middle Devonian Hollard Mound from the Antiatlas of Morocco [1], Late Devonian limestone lenses with the dimerelloid brachiopod Dzieduszyckia from the Western Meseta of Morocco [2], Middle Mississippian limestones with the dimerelloid brachiopod Ibergirhynchia from the Harz Mountains of Germany [3], Early Pennsylvanian limestones from the Tantes Mound in the High Pyrenees of France [4], and Late Pennsylvanian limestone lenses from the Ganigobis Shale Member of southern Namibia [5]. Among these examples, the composition of seepage fluids varied substantially as inferred from delta C-13 values of early diagenetic carbonate phases. Delta C-13 values as low as -50 per mil from the Tantes Mound and -51 per mil from the Ganigobis limestones reveal seepage of biogenic methane, whereas values of -12 per mil from limestones with Dzieduszyckia associated with abundant pyrobitumen agree with oil seepage. Intermediate delta C-13 values of carbonate cements from the Hollard Mound and Ibergirhynchia deposits probably reflect seepage of thermogenic methane. It is presently very difficult to assess the faunal evolution at seeps in the Paleozoic based on the limited number of examples. Two of the known seeps were typified by extremely abundant rhynchonellide brachiopods of the superfamily Dimerelloidea. Bivalve mollusks and tubeworms were abundant at two of the known Paleozoic seep sites; one was dominated by bivalve mollusks (Hollard Mound, Middle Devonian), another was dominated by tubeworms (Ganigobis Shale Member, Late Pennsylvanian). The tubeworms from these two deposits are interpreted to represent vestimentiferan worms, based on studies of the taphonomy of modern vestimentiferans. However, this interpretation is in conflict with the estimated evolutionary age of vestimentiferans based on molecular clock methods

  10. Structural studies in limestone sulfidation

    SciTech Connect

    Fenouil, L.A.; Lynn, S.

    1993-05-01

    This study investigates the sulfidation of limestone at high temperatures (700--900{degree}C) as the first step in the design of a High-Temperature Coal-Gas Clean-Up system using millimeter-size limestone particles. Several workers have found that the rate of this reaction significantly decreases after an initial 10 to 15% conversion of CaCO{sub 3} to CaS. The present work attempts to explain this feature. It is first established that millimeter-size limestone particles do not sinter at temperatures up to the CaCO{sub 3} calcination point (899{degree}C at 1.03 bar CO{sub 2} partial pressure). It is then shown that CaS sinters rapidly at 750 to 900{degree}C if CO{sub 2} is present in the gas phase. Scanning Electron Microscope (SEM) photographs and Electron Dispersive Spectroscopy (EDS) data reveal that the CaS product layer sinters and forms a quasi-impermeable coating around the CaCO{sub 3} grains that greatly hinders more H{sub 2}S from reaching the still unreacted parts of the stone. Moreover, most of the pores initially present within the limestone structure begin to disappear or, at least, are significantly reduced in size. From then on, subsequent conversion is limited by diffusion of H{sub 2}S through the CaS layer, possibly by S{sup 2{minus}} ionic diffusion. The kinetics is then adequately described by a shrinking-core model, in which a sharp front of completely converted limestone is assumed to progress toward the center of the pellet. Finally, experimental evidence and computer simulations using simple sintering models suggest that the CaS sintering, responsible for the sharp decrease in the sulfidation rate, is surface-diffusion controlled.

  11. CALCIUM CARBONATE DISSOLUTION RATE IN LIMESTONE CONTACTORS

    EPA Science Inventory

    The rate of carbonate mineral dissolution from limestone was studied using a rotating disk apparatus and samples of limestone of varied composition. The purpose of this study was to determine the effect of limestone composition on the kinetics of carbonate mineral dissolution. Th...

  12. Play & Play Grounds. A Report.

    ERIC Educational Resources Information Center

    Stone, Jeannette Galambos

    Using camera and tape recorder, a photographer and an early childhood specialist explored as a team the universe of children's outdoor play, seeking worthy and innovative ideas and stressing urban playground problems and solutions. The resulting photographs and text focus on (1) the characteristics of play, (2) the nature of playgrounds, and (3)…

  13. Where to Next for School Playground Interventions to Encourage Active Play? An Exploration of Structured and Unstructured School Playground Strategies

    ERIC Educational Resources Information Center

    Hyndman, Brendon

    2015-01-01

    An emerging public health priority is to enhance children's opportunities for active play. Children spend a large proportion of weekdays in schools, making schools an influential and suitable setting to promote children's active play. Rather than continually increasing the burdens placed upon busy teaching staff, the use of school playground…

  14. Geochemistry of laboratory anoxic limestone drains

    SciTech Connect

    Sterner, P.; Skousen, J.; Donovan, J.

    1998-12-31

    An anoxic limestone drain (ALD) is a passive treatment system for treating acid mine drainage (AMD). Historically it has been thought that AMD containing Fe{sup 3+} and Al{sup 3+} severely inhibits or stops limestone dissolution due to coating of limestone surfaces by precipitates generated during the neutralization process. Limestone dissolution in field ALDs is difficult to quantify because sampling of the water in ALDs at various locations is not possible, and fluctuations in flow and water chemistry affect limestone dissolution rates. Laboratory experiments were developed to determine the effects of Fe{sup 3+} and Al{sup 3+} precipitation on limestone dissolution and the controlling precipitation reactions. Synthetic AMD containing Fe{sup 3+} or Al{sup 3+} with and without sulfate was pumped through limestone-packed columns constructed with three sampling ports at equidistant intervals along the column. Water and sediments were periodically extracted for analysis at all sampling ports over a 12-hr period. Results show the majority of limestone dissolution occurred within the first 1.2 hrs of water-limestone contact. Limestone dissolution rate decreased with time and distance along the flow path. Higher concentrations of Fe{sup 3+} and Al{sup 3+} (increased in mineral acidity and ionic strength) enhanced limestone dissolution. Geochemical modeling predicted that solutions were nearest equilibrium with respect to the amorphic metal hydroxide phases. Although solutions were periodically oversaturated with respect to sulfate containing minerals, but no x-ray identifiable sulfate minerals were found in the solid phase. The data suggest that smaller anoxic limestone drains may be used when the goal is to neutralize mineral acidity, thus reducing spatial requirements. However, if the goal is to treat AMD to NPDES limits, ALDs may not be a viable long term treatment alternative.

  15. Meteoric stabilization and preservation of limestone within late Proterozoic Beck Spring Dolomite of eastern California

    SciTech Connect

    Zempolich, W.G.; Wilkinson, B.H.; Lohmann, K.C.

    1989-04-01

    Petrographic and geochemical study of limestone, silicified carbonate, and dolostone indicates that meteoric diagenetic processes and paleogeographic position played important roles in the stabilization and preservation of limestone within the pervasively dolomitized Beck Spring Dolomite. The authors conclude that Beck Spring marine cement allochems precipitated as aragonite and high-magnesium calcite. In the vicinity of Saratoga Spring, these metastable mineralogies were dissolved, eroded, stabilized to calcite, and replaced by silica through interaction with meteoric waters. Early stabilization of limestone components along the margin of the Amargosa basin apparently decreased susceptibility to subsequent dolomitization.

  16. CO2 mitigation via accelerated limestone weathering

    USGS Publications Warehouse

    Rau, G.H.; Knauss, K.G.; Langer, W.H.; Caldeira, K.

    2004-01-01

    The climate and environmental impacts of the current, carbon-intensive energy usage demands that effective and practical energy alternatives and CO2 mitigation strategies be found. A discussion on CO2 mitigation via accelerated limestone weathering covers limestone and seawater availability and cost; reaction rates and densities; effectiveness in CO2 sequestration; and environmental impacts and benefits.

  17. SNiPlay3: a web-based application for exploration and large scale analyses of genomic variations.

    PubMed

    Dereeper, Alexis; Homa, Felix; Andres, Gwendoline; Sempere, Guilhem; Sarah, Gautier; Hueber, Yann; Dufayard, Jean-François; Ruiz, Manuel

    2015-07-01

    SNiPlay is a web-based tool for detection, management and analysis of genetic variants including both single nucleotide polymorphisms (SNPs) and InDels. Version 3 now extends functionalities in order to easily manage and exploit SNPs derived from next generation sequencing technologies, such as GBS (genotyping by sequencing), WGRS (whole gre-sequencing) and RNA-Seq technologies. Based on the standard VCF (variant call format) format, the application offers an intuitive interface for filtering and comparing polymorphisms using user-defined sets of individuals and then establishing a reliable genotyping data matrix for further analyses. Namely, in addition to the various scaled-up analyses allowed by the application (genomic annotation of SNP, diversity analysis, haplotype reconstruction and network, linkage disequilibrium), SNiPlay3 proposes new modules for GWAS (genome-wide association studies), population stratification, distance tree analysis and visualization of SNP density. Additionally, we developed a suite of Galaxy wrappers for each step of the SNiPlay3 process, so that the complete pipeline can also be deployed on a Galaxy instance using the Galaxy ToolShed procedure and then be computed as a Galaxy workflow. SNiPlay is accessible at http://sniplay.southgreen.fr.

  18. SNiPlay3: a web-based application for exploration and large scale analyses of genomic variations

    PubMed Central

    Dereeper, Alexis; Homa, Felix; Andres, Gwendoline; Sempere, Guilhem; Sarah, Gautier; Hueber, Yann; Dufayard, Jean-François; Ruiz, Manuel

    2015-01-01

    SNiPlay is a web-based tool for detection, management and analysis of genetic variants including both single nucleotide polymorphisms (SNPs) and InDels. Version 3 now extends functionalities in order to easily manage and exploit SNPs derived from next generation sequencing technologies, such as GBS (genotyping by sequencing), WGRS (whole gre-sequencing) and RNA-Seq technologies. Based on the standard VCF (variant call format) format, the application offers an intuitive interface for filtering and comparing polymorphisms using user-defined sets of individuals and then establishing a reliable genotyping data matrix for further analyses. Namely, in addition to the various scaled-up analyses allowed by the application (genomic annotation of SNP, diversity analysis, haplotype reconstruction and network, linkage disequilibrium), SNiPlay3 proposes new modules for GWAS (genome-wide association studies), population stratification, distance tree analysis and visualization of SNP density. Additionally, we developed a suite of Galaxy wrappers for each step of the SNiPlay3 process, so that the complete pipeline can also be deployed on a Galaxy instance using the Galaxy ToolShed procedure and then be computed as a Galaxy workflow. SNiPlay is accessible at http://sniplay.southgreen.fr. PMID:26040700

  19. Exploring the Behavioral Patterns of Learners in an Educational Massively Multiple Online Role-Playing Game (MMORPG)

    ERIC Educational Resources Information Center

    Hou, Huei-Tse

    2012-01-01

    Massively multiple online role-playing games (MMORPGs) are very popular among students. Educational MMORPGs, however, are very rare, as are studies on gamers' behavioral patterns during such games. The current study is an empirical observation and analysis of the behavioral patterns of 100 gamers participating in an educational MMORPG called…

  20. SNiPlay3: a web-based application for exploration and large scale analyses of genomic variations.

    PubMed

    Dereeper, Alexis; Homa, Felix; Andres, Gwendoline; Sempere, Guilhem; Sarah, Gautier; Hueber, Yann; Dufayard, Jean-François; Ruiz, Manuel

    2015-07-01

    SNiPlay is a web-based tool for detection, management and analysis of genetic variants including both single nucleotide polymorphisms (SNPs) and InDels. Version 3 now extends functionalities in order to easily manage and exploit SNPs derived from next generation sequencing technologies, such as GBS (genotyping by sequencing), WGRS (whole gre-sequencing) and RNA-Seq technologies. Based on the standard VCF (variant call format) format, the application offers an intuitive interface for filtering and comparing polymorphisms using user-defined sets of individuals and then establishing a reliable genotyping data matrix for further analyses. Namely, in addition to the various scaled-up analyses allowed by the application (genomic annotation of SNP, diversity analysis, haplotype reconstruction and network, linkage disequilibrium), SNiPlay3 proposes new modules for GWAS (genome-wide association studies), population stratification, distance tree analysis and visualization of SNP density. Additionally, we developed a suite of Galaxy wrappers for each step of the SNiPlay3 process, so that the complete pipeline can also be deployed on a Galaxy instance using the Galaxy ToolShed procedure and then be computed as a Galaxy workflow. SNiPlay is accessible at http://sniplay.southgreen.fr. PMID:26040700

  1. Sodium-limestone double alkali flue gas desulfurization process with improved limestone utilization

    SciTech Connect

    Biolchini, R.J.; Boward, W.L. Jr.; Wang, K.H.

    1987-08-18

    This patent describes a sodium-limestone double alkali process for the continuous desulfurization of flue gas, having the steps of absorbing sulfur dioxide from an SO/sub 2/-containing gas stream in an absorber with an aqueous solution of sodium sulfite and sodium bisulfite, diverting at least a portion of the absorber effluent solution for regeneration with limestone, introducing limestone into the diverted absorber effluent solution to convert bisulfite to sulfite, separating by-product solids from the limestone-treated solution, and returning regenerated solution to the absorber, the improvement for increasing the utilization of the limestone used during the regeneration operation.

  2. Clay Play

    ERIC Educational Resources Information Center

    Rogers, Liz; Steffan, Dana

    2009-01-01

    This article describes how to use clay as a potential material for young children to explore. As teachers, the authors find that their dialogue about the potential of clay as a learning medium raises many questions: (1) What makes clay so enticing? (2) Why are teachers noticing different play and conversation around the clay table as compared to…

  3. A Systems Approach to Identifying Exploration and Development Opportunities in the Illinois Basin: Digital Portifolio of Plays in Underexplored Lower Paleozoic Rocks

    SciTech Connect

    Beverly Seyler; David Harris; Brian Keith; Bryan Huff; Yaghoob Lasemi

    2008-06-30

    This study examined petroleum occurrence in Ordovician, Silurian and Devonian reservoirs in the Illinois Basin. Results from this project show that there is excellent potential for additional discovery of petroleum reservoirs in these formations. Numerous exploration targets and exploration strategies were identified that can be used to increase production from these underexplored strata. Some of the challenges to exploration of deeper strata include the lack of subsurface data, lack of understanding of regional facies changes, lack of understanding the role of diagenetic alteration in developing reservoir porosity and permeability, the shifting of structural closures with depth, overlooking potential producing horizons, and under utilization of 3D seismic techniques. This study has shown many areas are prospective for additional discoveries in lower Paleozoic strata in the Illinois Basin. This project implemented a systematic basin analysis approach that is expected to encourage exploration for petroleum in lower Paleozoic rocks of the Illinois Basin. The study has compiled and presented a broad base of information and knowledge needed by independent oil companies to pursue the development of exploration prospects in overlooked, deeper play horizons in the Illinois Basin. Available geologic data relevant for the exploration and development of petroleum reservoirs in the Illinois Basin was analyzed and assimilated into a coherent, easily accessible digital play portfolio. The primary focus of this project was on case studies of existing reservoirs in Devonian, Silurian, and Ordovician strata and the application of knowledge gained to future exploration and development in these underexplored strata of the Illinois Basin. In addition, a review of published reports and exploration in the New Albany Shale Group, a Devonian black shale source rock, in Illinois was completed due to the recent increased interest in Devonian black shales across the United States. The New

  4. CO2 mitigation via accelerated limestone weathering

    USGS Publications Warehouse

    Rau, G.H.; Knauss, K.G.; Langer, W.H.; Caldeira, K.

    2004-01-01

    Accelerated weathering of limestone (AWL: CO22+ + CaCO3 + H2O ??? Ca2+ + 2HCO3- as a low-tech, inexpensive, high-capacity, environmentally-friendly CO2 capture and sequestration technology was evaluated. With access to seawater and limestone being essential to this approach, significant limestone resources were close to most CO2-emitting power plants along the coastal US. Waste fines, representing > 20% of current US crushed limestone production (> 109 tons/yr), could be used as an inexpensive source of AWL carbonate. AWL end-solution disposal in the ocean would significantly reduce effects on ocean pH and carbonate chemistry relative to those caused by direct atmospheric or ocean CO2 disposal. Indeed, the increase in ocean Ca2+ and bicarbonate offered by AWL should enhance growth of corals and other calcifying marine organisms.

  5. Exploration

    USGS Publications Warehouse

    Wilburn, D.R.

    2001-01-01

    Part of an annual review of mines and mineral resources in the U.S. An overview of nonfuel-mineral exploration in 2000 is presented. Principal exploration target was gold exploration in Latin America, Australia, and the U.S. There was a decrease of 18 percent in the exploration budget for gold as compared with the budget for 1999. Statistical information on nonfuel-mineral exploration worldwide is presented, analyzed, and interpreted.

  6. [Limestone and pyrite-limestone constructed wetlands for treating river water].

    PubMed

    Zhang, Jing; Li, Rui-hua; Li, Jie; Hu, Jun-song; Sun, Qian-qian

    2013-09-01

    Polluted river water was treated with limestone and pyrite-limestone subsurface horizontal constructed wetlands. The aims were to know the performance of two wetlands on removal of common pollutants, especially nitrogen and phosphorus, and analyze the actions of these minerals. The relationship between hydraulic retention time and purification performance of two constructed wetlands was studied. The optimal hydraulic retention time for pollutant removal was about 3 d, The average removal efficiency of COD, TN and TP were 51%, 70% and 95%, respectively. With same influent and hydraulic loading, the average removal efficiency of COD, NH4+ -N, TN and TP were 53.93%, 82.13%, 66%, 50.9%, and 51.66%, 77.43%, 72.06%, 97.35% for limestone and pyrite-limestone constructed wetlands, respectively. There were few differences between limestone and pyrite-limestone wetlands on COD removal, but the nitrogen and phosphorus removal of pyrite-limestone constructed wetland was higher than that of limestone constructed wetland. The phosphorus removal of pyrite-limestone wetland was more efficiency and stable, not affected by temperature.

  7. BASIC computer program calculates FGD limestone use

    SciTech Connect

    Buecker, B. )

    1992-09-01

    This paper reports that engineers can use available data with this computer program to predict how much limestone the FGD system will be used. Up to now, utilities with limestone FGD systems in their power plants have found it economical to scrub only the amount of gas needed to meet SO[sub 2] emissions limits. However, the Clean Air Act Amendments of 1990 and the rules allowing credits for reduced SO[sub 2] discharges make overscrubbing more attractive. The BASIC computer program in Figure 1 illustrates a method to calculate projected limestone use based on data routinely determined by utility engineers. The program, as it is written, has been used successfully to estimate limestone consumption on a 200-MW, coal-fired boiler with a wet-limestone, forced-air oxidized FGD system. This system meets the required SO[sub 2] emissions limit of 1.2 lb/MBtu. Two factors have made the program successful. First, gas flow to the scrubber is controlled with the help of a bypass system, whereby some of the untreated flue gas is injected directly into the stack. Thus, SO[sub 2] emissions are controlled by varying the amount of gas sent through the scrubber and not by changing process chemistry. Second, the utility has a single supplier of coal and a single supplier of high-purity limestone.

  8. Acid drainage response to surface limestone layers

    SciTech Connect

    Geidel, G.; Caruccio, F.T.

    1982-12-01

    A 150 acre drainage basin in an unreclaimed coal strip mine in east-central Ohio was studied and extensively monitored to determine the effect of a surface application of limestone on the ground water quality. Prior to the limestone treatment the ground and surface water of the basin was acidic due to pyrite oxidation in the spoil. In order to assess the effect of the limestone application the basin was divided into seven sub-basins, five of which were treated and two which served as controls. The seeps from the treated sub-basins with low acid concentrations became alkaline due to neutralization but after a long dry period, they returned to their acid condition. The moderately and highly acidic seeps showed a decline in the acid concentrations which could be attributed to a combination of neutralization and a decrease in the rate of pyrite oxidation. The results of this field study and simultaneous laboratory experiments showed that under natural conditions, with no limestone application, the acidity generated by pyrite oxidation in a backfill decreased. A surface application of limestone slightly enhanced the decrease in acidity by both neutralization and decreasing the rate of pyrite oxidation. However, the limestone application did not provide sufficient alkalinity to produce either neutral or alkaline discharges from the abandoned coal strip mine site.

  9. Exploration

    USGS Publications Warehouse

    Wilburn, D.R.; Porter, K.E.

    1999-01-01

    This summary of international nonfuel mineral exploration activities for 1998 draws on available data from literature, industry and US Geological Survey (USGS) specialists. Data on exploration budgets by region and commodity are reported, significant mineral discoveries and exploration target areas are identified and government programs affecting the mineral exploration industry are discussed. Inferences and observations on mineral industry direction are drawn from these data and discussions.

  10. Reducing energy-related CO2 emissions using accelerated weathering of limestone

    USGS Publications Warehouse

    Rau, G.H.; Knauss, K.G.; Langer, W.H.; Caldeira, K.

    2007-01-01

    The use and impacts of accelerated weathering of limestone (AWL; reaction: CO2+H2O+CaCO3???Ca2++2(HCO3-) is explored as a CO2 capture and sequestration method. It is shown that significant limestone resources are relatively close to a majority of CO2-emitting power plants along the coastal US, a favored siting location for AWL. Waste fines, representing more than 20% of current US crushed limestone production (>109 tonnes/yr), could provide an inexpensive or free source of AWL carbonate. With limestone transportation then as the dominant cost variable, CO2 mitigation costs of $3-$4/tonne appear to be possible in certain locations. Perhaps 10-20% of US point-source CO2 emissions could be mitigated in this fashion. It is experimentally shown that CO2 sequestration rates of 10-6 to 10-5 moles/sec per m2 of limestone surface area are achievable, with reaction densities on the order of 10-2 tonnes CO2 m-3day-1, highly dependent on limestone particle size, solution turbulence and flow, and CO2 concentration. Modeling shows that AWL would allow carbon storage in the ocean with significantly reduced impacts to seawater pH relative to direct CO2 disposal into the atmosphere or sea. The addition of AWL-derived alkalinity to the ocean may itself be beneficial for marine biota. ?? 2006 Elsevier Ltd. All rights reserved.

  11. Exploration

    USGS Publications Warehouse

    Wilburn, D.R.

    2005-01-01

    The worldwide budget for nonferrous, nonfuel mineral exploration was expected to increase by 58 percent in 2004 from the 2003 budget, according to Metals Economics Group (MEG) of Halifax, Nova Scotia. The increase comes two years after a five-year period of declining spending for mineral exploration (1998 to 2002). Figures suggest a subsequent 27 percent increase in budgeted expenditures from 2002 to 2003. For the second consecutive year, all regional exploration budget estimates were anticipated to increase.

  12. Effect of Limestone Fillers the Physic-Mechanical Properties of Limestone Concrete

    NASA Astrophysics Data System (ADS)

    bederina, Madani; makhloufi, Zoubir; bouziani, Tayeb

    This work focuses on the exploitation of local industrial wastes and their use in the formulation of new concretes which can be used in local constructions. The valorised materials are limestone crushing sand (0/5 mm) and limestone fillers (80 μm). The two materials are extracted from local aggregate crushing wastes. Thus, and since the used gravels are also of limestone nature, the formulated composite is a limestone concrete. So this study constitutes an experimental work that aims at the study of the effect of the addition of limestone fillers on the physico-mechanical behaviour of limestone concrete. To carry out this study, different proportions of fillers ranging from 0 to 40% were considered. Very important results have been achieved on the workability and strength. By increasing the amount of limestone filler in concrete, the first one improves, but the second one increases then decreases passing by an optimal content of fillers which gives a maximum mechanical strength. Finally, and concerning the dimensional variations, it is noteworthy that they decrease at the beginning till an optimal value of fillers content, but beyond this optimum, they start increasing without exceeding recommended values.

  13. Exploration

    USGS Publications Warehouse

    Wilburn, D.R.

    2002-01-01

    Exploration budgets fell for a fourth successive year in 2001. These decreases reflected low mineral commodity prices, mineral-market investment reluctance, company failures and a continued trend of company mergers and takeovers.

  14. Crystalline marble beats limestone for fluegas desulfurization

    SciTech Connect

    1996-05-01

    NovaCon Energy Systems, Inc. (Bedford, NY) has developed an alternative to conventional limestone sorbents. The new process uses a class of marble, selected with a proprietary model. Recent pilot- and full-scale demonstrations in pulverized-coal (PC) and circulating fluidized bed (CFB) boilers suggest that these patented sorbents outperform conventional limestone for the simultaneous control of SOx, NOx, and particulates during the combustion of coal and sulfur-rich fuels, such as oil, mixed municipal waste and used tires. Dubbed thermally active marbles (TAMs), these sorbents are chemically identical to grainy limestone (whose main constituent is calcium carbonate or calcite). However, thanks to the increased pressures and temperatures experienced during their geologic history, these metamorphic minerals have a regular crystalline structure that offers some advantages in the combustion zone. TAMs, on the other hand, enjoy better calcium-utilization rates because upon heating, they cleave along inter- and intra-crystalline faces, continuously exposing fresh surfaces. By minimizing the self-extinguishment suffered by limestone sorbents, TAMs are effective over operating temperatures from 1,200 F to 2,800 F, which is 400 F higher than other calcium-based sorbents. This allows them to be injected closer to the burner or combustion grate to maximize residence time in the unit.

  15. Acidic stream mitigation by limestone sand addition

    SciTech Connect

    Brant, D.L.; Marich, A.J. Jr.; Largent, K.L.

    1996-12-31

    The Town Line Run watershed comprises an area of 3,600 wooded acres. The tributaries feeding the stream consist of sandstone springs that do not contribute alkalinity to the watershed, leaving the stream susceptible to acid precipitation. This has a negative affect on Iser`s Run, a native brook trout fishery above the confluence with Town Line Run. The objective in stream liming is to improve water chemistry by increasing pH, alkalinity, and reducing acidity, aluminum, and iron. Introducing crushed limestone directly into a stream from a dump truck is an inexpensive but temporary solution to accomplish this objective. In this type of liming operation, a bed of limestone is spread down the stream channel by the momentum of the stream from the introduction point, rather than manually. Water moving across this bed dissolves the limestone, increasing the pH, alkalinity, and calcium while decreasing the acidity, iron, and aluminum concentrations of the water. The size of the limestone particles is important for this purpose because particles that are too small (<150 microns) will carried away, while particles that are too large (>1000 microns) will remain at the introduction point. Our study placed 80 tons of sand-sized limestone (85% calcite) in the stream channel at a single point. Water samples were collected monthly at the following sites (1) directly upstream of the addition site, (2) 100 yards downstream of the site, and (3) 2500 yards downstream of the site. Other sample locations include (4) upstream and (5) downstream of the Town Line Run- Iser`s Run confluence and the Casselman River upstream (6) and downstream (7) of Town Line Run. The samples were analyzed for pH. Specific conductivity, Alkalinity, Acidity, Iron, Manganese, Aluminum, and Sulfate.

  16. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States

    SciTech Connect

    Reimann, K.J.

    1991-09-01

    Gravimetric changes in marble and limestone briquettes exposed to outdoor environment at five sites in the eastern United States have been monitored since 1984. An earlier report describes procedures and results obtained in 1984--1988. This report presents the results of the exposure period 1984--1988 and reviews and summarizes those of prior years. A linear relationship was found between cumulative gravimetric losses and exposure period or rain depth. These losses resulted in an average recession rate of 14 to 24 {mu}m/yr for marble and twice that for limestone. Variations in recession among the various exposure sites can be ascribed to differences in rain depth and hydrogen ion concentration. The annual recession rates obtained from gravimetry yielded rates that were for marble twice those obtained from runoff experiments, and more than three times those for limestone; this indicates that physical erosion plays an important role. Gravimetric monitoring of exposed briquettes is continuing in a planned 10-yr program.

  17. Mineralogical characterization of the Shelburne marble and the Salem limestone

    SciTech Connect

    McGee, E.S.

    1989-01-01

    Samples of Shelburne marble and Salem limestone were selected to represent marbles and limestones used in buildings and monuments. The Royal variety of Shelburne marble is a white marble predominantly composed of calcite but has heterogeneously distributed gray inclusions. The select buff Salem limestone is a beige, homogeneous, fossiliferous limestone, predominantly composed of fragments of echinoderms and bryozoans. The author reports that both samples are appropriate test stones for the National Acid Precipitation Assessment Program stone exposure studies.

  18. Physicochemical characterizations of limestone for fluidized-bed coal combustion

    SciTech Connect

    Fuller, E.L. Jr.; Yoos, T.R. III; Walia, D.S.

    1981-05-01

    This study is an investigation of the physicochemical characteristics of three limestone samples, Quincy limestone (-20 + 60), Franklin limestone (-12 + 30), and Franklin limestone (-6 + 16), currently being tested at Oak Ridge National Laboratory for use in a fluidized-bed coal combustion unit. By correlating the chemistry, mineralogy, and surface area of these samples with empirical data obtained at Argonne National Laboratory, the sulfur capture ability and performance of these limestones can be loosely predicted. X-ray fluorescence and neutron activation analysis revealed a very high calcium content and very low concentrations of other elements in the three samples. X-ray diffraction patterns and petrographic examination of the limestone grains detected essentially no dolomite in the Quincy limestone or the fine Franklin limestone samples. The coarse Franklin limestone sample showed dolomite to be present in varying amounts up to maximum of 2.75%. Limited surface chemistry investigations of the samples were undertaken. Limestone and dolostone resources of the Tennessee Valley Authority region are widespread and abundant, and judged sufficient to meet industrial demand for many years. No problems are anticipated in securing limestone or dolostone supplies for a commercial fluidized-bed combustion plant in the Tennessee Valley Authority region. Transportation facilities and costs for limestone or dolostone will influence the siting of such a commercial fluidized-bed combustion plant. The most promising location in the Tennessee Valley Authority region at this time is Paducah, Kentucky.

  19. War, Conflict and Play. Debating Play

    ERIC Educational Resources Information Center

    Hyder, Tina

    2004-01-01

    Young refugees from many parts of the world are increasingly present in UK early years settings. This book explores the crucial importance of play for young refugee children's development. It considers the implications of war and conflict on young children and notes how opportunities for play are denied. It provides a framework for early years…

  20. Playful Gaming.

    ERIC Educational Resources Information Center

    Makedon, Alexander

    A philosophical analysis of play and games is undertaken in this paper. Playful gaming, which is shown to be a synthesis of play and games, is utilized as a category for undertaking the examination of play and games. The significance of playful gaming to education is demonstrated through analyses of Plato's, Dewey's, Sartre's, and Marcuse's…

  1. Drenov Grič black limestone as a heritage stone from Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Rožič, Boštjan; Žbona, Nina; Bedjanič, Mojca; Mladenović, Ana

    2016-04-01

    The limestone known as Drenov Grič black limestone is considered one of the most beautiful Slovenian natural stones due to its homogenous black colour interwoven with white veins. Over the centuries it has been exploited from three major quarries west of Ljubljana, with the main quarry at Drenov Grič playing the primary role in supplying building material for the central parts of Slovenia. All the quarries are currently not active. In the area of Drenov grič, one locality of black limestone is protected - Kuclerjev kamnolom quarry. It has the status of 'valuable natural feature of national importance' and is protected as a natural monument. This well-stratified micritic limestone of Triassic (Carnian) age occurs in 10-80 cm thick beds, with thin marl interlayers. The stone contains abundant fossil bivalves and ostracods. Apart from calcite as the main component, dolomite, quartz, illite/muscovite and pyrite are also present. The limestone is relatively rich in carbonaceous and bituminous organic matter, which is responsible for the black colour of the stone. This component does not have any adverse effect on mechanical and physical characteristics. As the lime¬stone is dense, thus facilitating a good polish, it has been commercially considered as marble. The stone has been widely used in Slovenian monuments, not only in Ljubljana but also in other regions of Slovenia. Many inner and outdoor architectural elements were made of this limestone, particularly in the baroque period, which was known for the extensive use of black limestones also in other European countries. The most significant use of this limestone has been recorded in sculptured portals and altars. Some of the important buildings decorated utilising this stone, are the Ljubljana Cathedral, the St. James's Parish Church, and the Franciscan Church of the Annunciation, all of which are located in Ljubljana, some of them having been declared as cultural monuments of local or national importance. When

  2. Limestone reaction in calcium aluminate cement–calcium sulfate systems

    SciTech Connect

    Bizzozero, Julien Scrivener, Karen L.

    2015-10-15

    This paper reports a study of ternary blends composed of calcium aluminate cement, calcium sulfate hemihydrate and limestone. Compressive strength tests and hydration kinetics were studied as a function of limestone and calcium sulfate content. The phase evolution and the total porosity were followed and compared to thermodynamic simulation to understand the reactions involved and the effect of limestone on these binders. The reaction of limestone leads to the formation of hemicarboaluminate and monocarboaluminate. Increasing the ratio between sulfate and aluminate decreases the extent of limestone reaction.

  3. The Excellence of Play.

    ERIC Educational Resources Information Center

    Moyles, Janet R., Ed.

    Recognizing that for young children, play is a tool for learning, this book compiles contributions by different authors, reflecting both up-to-date research and current classroom practice as they relate to children's play. Part 1 of the book explores the value of play as a cross-cultural concept as well as one rooted in the Western world. Gender…

  4. Limestone quarrying and quarry reclamation in Britain

    NASA Astrophysics Data System (ADS)

    Gunn, J.; Bailey, D.

    1993-06-01

    Limestones have been worked for many thousands of years — initially for building stone and agricultural lime and more recently for a wide range of construction and industrial uses. In most industrialized countries limestone quarries represent the most visually obvious and, in both process and landform terms, the most dramatic anthropogenic impact on karst terrain. However, quarrying has, to date, received surprisingly little attention from karst scientists. Research in the English Peak District suggested that the postexcavation evolution of quarried limestone rock faces was in part a result of the methods used in their excavation, and this led to the development of a technique designed to reduce the visual and environmental impacts of modern quarries by “Landform replication. ” This involves the use of controlled “restoration blasting” techniques on quarried rock slopes to construct a landform sequence similar to that in the surrounding natural landscape. The constructed landforms are then partially revegetated using appropriate wildflower, grass, and/or tree species.

  5. Simulation of Hypervelocity Penetration in Limestone

    SciTech Connect

    Antoun, T; Glenn, L; Walton, O; Goldstein, P; Lomov, I; Liu, B

    2005-05-31

    A parameter study was performed to examine the (shock) damage obtained with long-rod and spherical mono-material penetrators impacting two varieties of limestone. In all cases, the impacts were assumed to be normal to the plane of the rock and at zero angle of attack (in the case of the rods). Impact velocities ranged to 15 km/s but most calculations were performed at 4 and 6 km/s and the penetrator mass was fixed at 1000 kg. For unlined underground structures, incipient damage was defined to occur when the peak stress, {sigma}{sub pk}, exceeds 1 kb (100 MPa) and the applied impulse per unit area, I{sub pk}, exceeds 1 ktap (1 kb-{micro}s). Severe damage was assumed to occur when {sigma}{sub pk} exceeds 1 kb and I{sub pk} exceeds 1000 ktaps. Using the latter definition it was found that severe damage in hard, non-porous limestone with spherical impactors extended to a depth of 9 m on-axis for an impact velocity of 4 km/s and 12 m at 6 km/s. Cylinders with length-to-diameter (L/D) ratio of 8.75 achieved depth to severe damage of 23 m and 40 m, respectively under the same conditions. For a limestone medium with 2% initial gas porosity, the latter numbers were reduced to 12 m and 18 m.

  6. Oil reservoirs in grainstone aprons around Bryozoan Mounds, Upper Harrodsburg Limestone, Mississippian, Illinois Basin

    SciTech Connect

    Jobe, H.; Saller, A.

    1995-06-01

    Several oil pools have been discovered recently in the upper Harrodsburg Limestone (middle Mississippian) of the Illinois basin. A depositional model for bryozoan mound complexes has allowed more successful exploration and development in this play. In the Johnsonville area of Wayne County, Illinois, three lithofacies are dominant in the upper Harrodsburg: (1) bryozoan boundstones, (2) bryozoan grainstones, and (3) fossiliferous wackestones. Bryozoan boundstones occur as discontinuous mounds and have low porosity. Although bryozoan boundstones are not the main reservoir lithofacies, they are important because they influenced the distribution of bryozoan grainstones and existing structure. Bryozoan grainstones have intergranular porosity and are the main reservoir rock. Bryozoan fragments derived from bryozoan boundstone mounds were concentrated in grainstones around the mounds. Fossiliferous wackestones are not porous and form vertical and lateral seals for upper Harrodsburg grainstones. Fossiliferous wackestones were deposited in deeper water adjacent to bryozoan grainstone aprons, and above grainstones and boundstones after the mounds were drowned. Upper Harrodsburg oil reservoirs occur where grainstone aprons are structurally high. The Harrodsburg is a good example of a carbonate mound system where boundstone cores are not porous, but adjacent grainstones are porous. Primary recovery in these upper Harrodsburg reservoirs is improved by strong pressure support from an aquifer in the lower Harrodsburg. Unfortunately, oil production is commonly decreased by water encroaching from that underlying aquifer.

  7. Play Therapy

    PubMed Central

    Kool, Ritesh

    2010-01-01

    Play therapy represents a unique form of treatment that is not only geared toward young children, but is translated into a language children can comprehend and utilize—the language of play. For the referring provider or practitioner, questions may remain regarding the nature, course, and efficacy of play therapy. This article reviews the theoretical underpinnings of play therapy, some practical considerations, and finally a summary of the current state of research in regard to play therapy. The authors present the practicing psychiatrist with a road map for referring a patient to play therapy or initiating it in appropriate cases. PMID:21103141

  8. Acid mine drainage neutralization in a pilot sequencing batch reactor using limestone from a paper and pulp industry.

    PubMed

    Vadapalli, V R K; Zvimba, J N; Mathye, M; Fischer, H; Bologo, L

    2015-01-01

    This study investigated the implications of using two grades of limestone from a paper and pulp industry for neutralization of acid mine drainage (AMD) in a pilot sequencing batch reactor (SBR). In this regard, two grades of calcium carbonate were used to neutralize AMD in a SBR with a hydraulic retention time (including settling) of 100 min and a sludge retention time of 360 min, by simultaneously monitoring the Fe(II) removal kinetics and overall assessment of the AMD after treatment. The Fe(II) kinetics removal and overall AMD treatment were observed to be highly dependent on the limestone grade used, with Fe(II) completely removed to levels lower than 50 mg/L in cycle 1 after 30 min using high quality or pure paper and pulp limestone. On the contrary, the other grade limestone, namely waste limestone, could only achieve a similar Fe(II) removal efficiency after four cycles. It was also noticed that suspended solids concentration plays a significant role in Fe(II) removal kinetics. In this regard, using pure limestone from the paper and pulp industry will have advantages compared with waste limestone for AMD neutralization. It has significant process impacts for the SBR configuration as it allows one cycle treatment resulting in a significant reduction of the feed stock, with subsequent generation of less sludge during AMD neutralization. However, the use of waste calcium carbonate from the paper and pulp industry as a feed stock during AMD neutralization can achieve significant cost savings as it is cheaper than the pure limestone and can achieve the same removal efficiency after four cycles.

  9. Reducing Energy-Related CO2 Emissions Using Accelerated Limestone Weathering

    SciTech Connect

    Rau, G H; Knauss, K G; Langer, W H; Caldeira, K

    2004-04-27

    Following earlier descriptions, the use and impacts of accelerated weathering of limestone AWL; reaction: CO{sub 2} + H{sub 2}O + CaCO{sub 3} {yields} Ca{sup 2+} + 2(HCO{sub 3}{sup -}) as a CO{sub 2} capture and sequestration method is further explored. Since ready access to the ocean is likely an essential requirement for AWL, it is shown that significant limestone resources are relatively close to a majority of CO{sub 2}-emitting power plants along the coastal US. Furthermore, waste fines, representing more than 20% of current US crushed limestone production (>10{sup 9} tonnes/yr), could be used in many instances as an inexpensive or free source of AWL carbonate. With limestone transportation to coastal sites then as the dominant cost variable, CO{sub 2} sequestration (plus capture) costs of $3-$4/tonne are achievable in certain locations. While there is vastly more limestone and water on earth than that required for AWL to capture and sequester all fossil fuel CO{sub 2} production, the transportation cost of bringing limestone, seawater, and waste CO{sub 2} into contact likely limits the method's applicability to perhaps 10-20% of US point-source emissions. Using a bench-scale laboratory reactor, it is shown that CO{sub 2} sequestration rates of 10{sup -6} to 10{sup -5} moles/sec per m{sup 2} of limestone surface area are readily achievable using seawater. This translates into reaction densities as high as 2 x 10{sup -2} tonnes CO{sub 2} m{sup -3}day{sup -1}, highly dependent on limestone particle size, solution turbulence and flow, and CO{sub 2} concentration. Modeling of AWL end-solution disposal in the ocean shows significantly reduced effects on ocean pH and carbonate chemistry relative to those caused by direct CO{sub 2} disposal into the atmosphere or ocean. In fact the increase in ocean Ca{sup 2+} and bicarbonate offered by AWL should significantly enhance the growth of corals and other marine calcifiers whose health is currently being threatened by

  10. City Play.

    ERIC Educational Resources Information Center

    Dargan, Amanda; Zeitlin, Steve

    2000-01-01

    Today, fewer city blocks preserve the confidence of lifestyle and urban geography that sustain traditional games and outdoor play. Large groups of children choosing sides and organizing Red Rover games are no longer commonplace. Teachers must encourage free play; urban planners must build cities that are safe play havens. (MLH)

  11. CO2 MITIGATION VIA ACCELERATED LIMESTONE WEATHERING

    SciTech Connect

    Rau, G H; Knauss, K G; Langer, W H; Caldeira, K G

    2004-02-27

    The climate and environmental impacts of our current, carbon-intensive energy usage demands that effective and practical energy alternatives and CO2 mitigation strategies be found. As part of this effort, various means of capturing and storing CO2 generated from fossil-fuel-based energy production are being investigated. One of the proposed methods involves a geochemistry-based capture and sequestration process that hydrates point-source, waste CO2 with water to produce a carbonic acid solution. This in turn is reacted and neutralized with limestone, thus converting the original CO2 gas to calcium bicarbonate in solution, the overall reaction being:

  12. The Helderberg limestone of central Pennsylvania

    USGS Publications Warehouse

    Reeside, John B.

    1917-01-01

    This paper presents the results of a study made during 1913, 1914, and 1915, while the writer was a student at Johns Hopkins University. The formations discussed have been studies in Maryland, New Jersey, and New York, and described with more or less detail, but concerning their occurrence in the intervening area in Pennsylvania little exact information has been available. The conflict in opinion as to the proper position and correlation of the Keyser limestone and as to the interpretation of some of the standard New York sections has made further data very desirable, and the present paper is an attempt to meet a part of the deficiency.

  13. African oil plays

    SciTech Connect

    Clifford, A.J. )

    1989-09-01

    The vast continent of Africa hosts over eight sedimentary basins, covering approximately half its total area. Of these basins, only 82% have entered a mature exploration phase, 9% have had little or no exploration at all. Since oil was first discovered in Africa during the mid-1950s, old play concepts continue to bear fruit, for example in Egypt and Nigeria, while new play concepts promise to become more important, such as in Algeria, Angola, Chad, Egypt, Gabon, and Sudan. The most exciting developments of recent years in African oil exploration are: (1) the Gamba/Dentale play, onshore Gabon; (2) the Pinda play, offshore Angola; (3) the Lucula/Toca play, offshore Cabinda; (4) the Metlaoui play, offshore Libya/Tunisia; (5) the mid-Cretaceous sand play, Chad/Sudan; and (6) the TAG-I/F6 play, onshore Algeria. Examples of these plays are illustrated along with some of the more traditional oil plays. Where are the future oil plays likely to develop No doubt, the Saharan basins of Algeria and Libya will feature strongly, also the presalt of Equatorial West Africa, the Central African Rift System and, more speculatively, offshore Ethiopia and Namibia, and onshore Madagascar, Mozambique, and Tanzania.

  14. Introduction to limestone flue gas desulfurization: Videotape workbook

    SciTech Connect

    Not Available

    1988-01-01

    The workbook is designed to accompany the Electric Power Research Institute's (EPRI's) videotape, ''Introduction to Limestone Flue Gas Desulfurization.'' To complement the videotape, the workbook provides additional information on limestone flue gas desulfurization (FGD) and a guide to sources of still more information. The videotape itself presents an introduction to the chemistry involved in a limestone FGD system. Following a description of a typical system, the basic chemical reactions that occur in this process are detailed. The most common operation problems in limestone FGD---low sulfur dioxide removal, low limestone utilization, and scaling---are reviewed with regard to how process chemistry can be controlled to alleviate these problems. This tape is an introduction only; future tapes will cover limestone FGD performance indicators and troubleshooting in more detail.

  15. Limestone types used from the classic Karst region in Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Mirtič, Breda; Mladenović, Ana; Rožič, Boštjan; Bedjanič, Mojca; Kortnik, Jože; Šmuc, Andrej

    2014-05-01

    The paper presents a variety of limestones from the Karst Region that is one of the most interesting areas containing reserves of natural stones in Slovenia. The region is mainly composed of Cretaceous shallow-water limestone, with the most common type currently excavated being the rudist limestone of the Lipica Formation, which dates to the Santonian to Campanian. Limestones of this formation are mainly represented by a light grey, thick-bedded to massive Lipica limestone rich in (largely fragmented) rudists. Rudist shells can be either relatively well preserved (such as in Lipica Fiorito quarried limestone) or almost completely disintegrated and intensively endolitised (Lipica Unito quarried limestone). Beside the Lipica Formation, natural stone types have been excavated from two other formations or members in the Karst region: the Repen Formation (Repen and Kopriva limestones), and the Tomaj Limestone (dark, laminated limestone within the Lipica Formation). As documented, the region has been associated with the quarrying and processing of stone at least for over two thousand years, i.e. since the Roman period. Although a large number of quarries in all mentioned formations are documented in the Karst region, many are inactive nowadays. Some of the quarries are declared as geological monuments of national importance or officially protected as a natural monument. Karst limestones are considered the highest quality calcareous natural stones in Slovenia. They are characterised by high density, low water absorption and low open porosity; consequently they also exhibit high frost and salt resistance as well as high compressive and flexural strength. Besides in the Karst region and other parts of Slovenia, the Karst limestones were used in the construction of several important buildings and monuments in many other European Countries, and worldwide. Nowadays, they are most commonly used in the construction of façade cladding, pavements, window sills, staircases, indoor

  16. Early evolution of the southern margin of the Neuquén Basin, Argentina: Tectono-stratigraphic implications for rift evolution and exploration of hydrocarbon plays

    NASA Astrophysics Data System (ADS)

    D'Elia, Leandro; Bilmes, Andrés; Franzese, Juan R.; Veiga, Gonzalo D.; Hernández, Mariano; Muravchik, Martín

    2015-12-01

    Long-lived rift basins are characterized by a complex structural and tectonic evolution. They present significant lateral and vertical stratigraphic variations that determine diverse basin-patterns at different timing, scale and location. These issues cause difficulties to establish facies models, correlations and stratal stacking patterns of the fault-related stratigraphy, specially when exploration of hydrocarbon plays proceeds on the subsurface of a basin. The present case study corresponds to the rift-successions of the Neuquén Basin. This basin formed in response to continental extension that took place at the western margin of Gondwana during the Late Triassic-Early Jurassic. A tectono-stratigraphic analysis of the initial successions of the southern part of the Neuquén Basin was carried out. Three syn-rift sequences were determined. These syn-rift sequences were located in different extensional depocentres during the rifting phases. The specific periods of rifting show distinctly different structural and stratigraphic styles: from non-volcanic to volcanic successions and/or from continental to marine sedimentation. The results were compared with surface and subsurface interpretations performed for other depocentres of the basin, devising an integrated rifting scheme for the whole basin. The more accepted tectono-stratigraphic scheme that assumes the deposits of the first marine transgression (Cuyo Cycle) as indicative of the onset of a post-rift phase is reconsidered. In the southern part of the basin, the marine deposits (lower Cuyo Cycle) were integrated into the syn-rift phase, implying the existence of different tectonic signatures for Cuyo Cycle along the basin. The rift climax becomes younger from north to south along the basin. The post-rift initiation followed the diachronic ending of the main syn-rift phase throughout the Neuquén Basin. Thus, initiation of the post-rift stage started in the north and proceeded towards the south, constituting a

  17. Play: early and eternal.

    PubMed Central

    Mears, C E; Harlow, H F

    1975-01-01

    A systematic 12-week investigation of development of play behavior was conducted with eight socially reared rhesus monkey infants. A new, basic and primary play form termed self-motion play or peragration was identified and examined. This behavior follows a human model which includes a wide range of pleasurable activities involving motion of the body through space, e.g., rocking, swinging, running, leaping, and water or snow skiing. It can be argued that self-motion play is the initial primate play form and because of its persistence constitutes a reinforcing agent for maintaining many complex patterns and even pastimes. Monkey self-motion play in the present study was divided into five separate patterns in order to compare the relative importance of social and individual peragration play, the role of apparatus and the overall developmental relationships between the different individual and social self-motion play patterns. The data showed that from 90 to 180 days of age self-motion play was independent of other forms of play, that individual self-motion play appeared earlier and with significantly greater increases in frequency than did social self-motion play, and that apparatus was a necessary component for significant increases in social self-motion play. Other findings were that self-motion play existed independent of locomotion and, though initiated by exploration, was separate from it. Therapeutic implications of self-motion play were discussed. Images PMID:1057178

  18. Neogene carbonate exploration play concepts for Northern New Guinea: New iteration from field work and seismic stratigraphy along the Northern New Guinea Fault Zone

    SciTech Connect

    Pigott, J.D.; Geiger, C. )

    1994-07-01

    Recent field reconnaissance, petrography, nanno and foraminifera age determinations, and seismic stratigraphy of the Sepik and Piore subbasins of northern New Guinea reveal the existence of an extensive, tectonically unstable, Miocene-Pliocene carbonate shelf system. These findings represent the first recorded evidence of northern Papuan limestones coeval in age to those of the hydrocarbon productive Salawati Basin of Irian Jaya. Moreover, these observations also demonstrate the significance of episodic activities of the northern New Guinea fault zone upon the changes in carbonate sedimentation and diagenesis. During the Neogene, algal biosparites to foraminiferal biomicrites defined the clean portion of a mixed clastic-carbonate shelf system of the northern New Guinea basin, which began at the central New Guinea cordillera and deepened northward. This shelf was interrupted by coral-coralline algal boundstone fringing- to patch-reef buildups with associated skeletal grainstones. Clean carbonates were spatially and temporally restricted to basement blocks, which episodically underwent uplift while terrigenous dilutes carbonates were more common in adjacently subsiding basement block bathymetric lows. These tectonic expressions were caused by the spatially transient nature of constraining bends of the evolving north New Guinea faults. As shown by seismic stratigraphy, by the late Miocene to the early Pliocene the uplift of the Bewani-Torricelli Mountains sagittally divided the shelf of the northern New Guinea basin into the Ramu-Sepik and the Piore basins. Continued regional sinistral transpression between the Pacific and the New Guinea leading edge of the Indo-Australian plates led to the reverse tilting of the Piore basin, the shallowing of the former distal shelf with concomitant extensive biolithite development (e.g., on subsiding volcanic islands) eventual uplifting of the Oenake Range, and en echelon faulting of the Bewani-Torricelli Mountains.

  19. Pretend play.

    PubMed

    Weisberg, Deena Skolnick

    2015-01-01

    Pretend play is a form of playful behavior that involves nonliteral action. Although on the surface this activity appears to be merely for fun, recent research has discovered that children's pretend play has connections to important cognitive and social skills, such as symbolic thinking, theory of mind, and counterfactual reasoning. The current article first defines pretend play and then reviews the arguments and evidence for these three connections. Pretend play has a nonliteral correspondence to reality, hence pretending may provide children with practice with navigating symbolic relationships, which may strengthen their language skills. Pretend play and theory of mind reasoning share a focus on others' mental states in order to correctly interpret their behavior, hence pretending and theory of mind may be mutually supportive in development. Pretend play and counterfactual reasoning both involve representing nonreal states of affairs, hence pretending may facilitate children's counterfactual abilities. These connections make pretend play an important phenomenon in cognitive science: Studying children's pretend play can provide insight into these other abilities and their developmental trajectories, and thereby into human cognitive architecture and its development.

  20. Pretend play.

    PubMed

    Weisberg, Deena Skolnick

    2015-01-01

    Pretend play is a form of playful behavior that involves nonliteral action. Although on the surface this activity appears to be merely for fun, recent research has discovered that children's pretend play has connections to important cognitive and social skills, such as symbolic thinking, theory of mind, and counterfactual reasoning. The current article first defines pretend play and then reviews the arguments and evidence for these three connections. Pretend play has a nonliteral correspondence to reality, hence pretending may provide children with practice with navigating symbolic relationships, which may strengthen their language skills. Pretend play and theory of mind reasoning share a focus on others' mental states in order to correctly interpret their behavior, hence pretending and theory of mind may be mutually supportive in development. Pretend play and counterfactual reasoning both involve representing nonreal states of affairs, hence pretending may facilitate children's counterfactual abilities. These connections make pretend play an important phenomenon in cognitive science: Studying children's pretend play can provide insight into these other abilities and their developmental trajectories, and thereby into human cognitive architecture and its development. PMID:26263228

  1. Role Playing and Skits

    ERIC Educational Resources Information Center

    Letwin, Robert, Ed.

    1975-01-01

    Explores non-scripted role playing, dialogue role playing, sociodrama, and skits as variations of simulation techniques. Provides step-by-step guidelines for conducting such sessions. Successful Meetings, Bill Communications, Inc., 1422 Chestnut Street, Philadelphia, Pa. 19102. Subscription Rates: yearly (US, Canada, Mexico) $14.00; elsewhere,…

  2. Playing Shakespeare.

    ERIC Educational Resources Information Center

    Bashian, Kathleen Ryniker

    1993-01-01

    Describes a yearlong project at 12 Catholic middle schools in the Diocese of Arlington, Virginia, to incorporate the plays of William Shakespeare into the curriculum. Teachers attended university lectures and directed students in performances of the plays. Concludes that Shakespeare can be understood and enjoyed by middle school students. (BCY)

  3. Why Play?

    ERIC Educational Resources Information Center

    Weininger, O.

    This paper draws together briefly theories and knowledge from research in morphology and cognitive psychology, as well as some hypothetical information from traditional psychiatry, to show the ramifications of play in children's development. Play is defined as any of a wide variety of behaviors through which an individual attempts to discover what…

  4. Shadow Play

    ERIC Educational Resources Information Center

    Trundle, Kathy Cabe; Hilson, Margilee P.

    2012-01-01

    A bunny rabbit playfully hops across the wall. Then hands realign and fingers shift to make a hawk soar toward the ceiling. Most children have enjoyed the delightful experience of playing with shadow puppets. The authors build on this natural curiosity to help students link shadows to complex astronomical concepts such as seasons. The…

  5. Play concepts-northwest Palawan, Philippines

    NASA Astrophysics Data System (ADS)

    Williams, Harold H.

    The offshore area of northwest Palawan, Philippines, contains a number of provenexploration plays. These include • pinnacle reefs developed on Nido carbonate platforms (e.g. Nido, Matinloc, Cadlao);• a seaward horst block reef fairway with large pinnacle reefs (e.g. Malampaya—Camago trend);• early Miocene Galoc Clastic Unit turbidites (e.g. Octon, Galoc); and• four-way dip closures (e.g. West Linapacan, Octon). The recent discovery by Fletcher Challenge Petroleum at Calauit Field has shown a potentialexploration play in deep-water Nido Limestone turbidites. The traditional and, to date, only economically productive play in northwest Palawan has been the Nido Limestone reefs. This paper presents a review of the old play types and presents new untested play types. These new play types include • pre-Nido syn-rift plays;• pre-Nido marine turbidite play: and• mid-Miocene reefs. It also presents new insights into factors controlling reef development on the carbonate platforms where four reef types are now recognized. The Galoc Clastic Unit turbidite play is discussed and new play fairways presented.

  6. STEAM INJECTION INTO FRACTURED LIMESTONE AT LORING AIR FORCE BASE

    EPA Science Inventory

    A research project on steam injection for the remediation of spent chlorinated solvents from fractured limestone was recently undertaken at the former Loring AFB in Limestone, ME. Participants in the project include the Maine Department of Environmental Protection, EPA Region I,...

  7. [Analysis of trace elements in limestone for archeological functions

    SciTech Connect

    Blanc, A.; Holmes, L.; Harbottle, G.

    1998-12-31

    Numerous quarries in the Lutetian limestone formations of the Paris Basin provided stone for the building and the decoration of monuments from antiquity to the present. To determine the origin of stone used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 samples. Petrographic and paleontologic examination of thin sections allows geologists to distinguish Lutetian limestones from Jurassic and Cretaceous limestones. Geologists also seek to formulate hypotheses regarding the origin of Lutetian limestones used for building and sculpture in the Paris region. In the search for the sources of building and sculptural stone, the analytical methods of geologists are limited because often several quarries produce the same lithofacies. A new tool is now available, however, to attack questions of provenance raised by art historians. Because limestones from different sources have distinctive patterns of trace-element concentrations, compositional analysis by neutron activation allows one to compare building or sculptural stone from one monument with stone from quarries or other monuments. This analytical method subjects a powdered limestone sample to standard neutron activation analysis procedures at Brookhaven National Laboratory. With the help of computer programs, the compositional fingerprints of Lutetian limestones can be determined and stored in a database. The limestone database contains data for approximately 2,100 samples from monuments, sculptures and quarries. It is particularly rich in samples from the Paris Basin.

  8. Microfacies and diagenesis of the reefal limestone, Callovian Tuwaiq Mountain Limestone Formation, central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    EL-Sorogy, Abdelbaset S.; Almadani, Sattam A.; Al-Dabbagh, Mohammad E.

    2016-03-01

    In order to document the microfacies and diagenesis of the reefal limestone in the uppermost part of the Callovian Tuwaiq Mountain Limestone Formation at Khashm Al-Qaddiyah area, central Saudi Arabia, scleractinian corals and rock samples were collected and thin sections were prepared. Coral framestone, coral floatstone, pelloidal packstone, bioclastic packstone, bioclastic wacke/packstone, algal wackestone and bioclastic foraminiferal wacke/packstone were the recorded microfacies types. Cementation, recrystallization, silicification and dolomitization are the main diagenetic alterations affected the aragonitic skeletons of scleractinian corals. All coral skeletons were recrystallized, while some ones were dolomitized and silicified. Microfacies types, as well as the fossil content of sclearctinian corals, bivalves, gastropods, brachiopods and foraminifera indicated a deposition in environments ranging from shelf lagoon with open circulation in quiet water below wave base to shallow reef flank and organic build up for the uppermost reefal part of the Tuwaiq Formation in the study area.

  9. Recovery and recycling of limestone in LEC flue gas desulfurization

    SciTech Connect

    Gardner, N.C.; Adler, R.J.; Lin, Y.C.; Unger, M.E.; Lux, K.W. )

    1992-03-01

    Prudich et al. have proposed an attractive technology called Limestone Emission Control (LEC) for removing sulfur dioxide from flue gases. Beds of 1/8 inch wet limestone particles absorb the sulfur dioxide from the gases. Sulfates and sulfites deposit on the surfaces of the particles, limiting their utilization to about 20%. The unreacted portion of the limestone can be recovered by mechanical grinding and recycling, enabling high overall sorbent utilization. Favorable economic costs derive from small equipment, simplicity, and low sorbent cost. Our research concentrates on selecting and testing on a laboratory scale suitable candidate dry and wet grinding methods for recovering limestone in LEC flue from desulfurization. A wet grinding method based on the impeller fluidizer, a new type of slurry processor, receives special attention. The impeller fluidizer is a dosed cylindrical vessel with an impeller at one end. It combines the operations of wet grinding, washing, and transporting the spent and recovered limestone as an aqueous slurry.

  10. Preschoolers' Thinking during Block Play

    ERIC Educational Resources Information Center

    Piccolo, Diana L.; Test, Joan

    2010-01-01

    Children build foundations for mathematical thinking in early play and exploration. During the preschool years, children enjoy exploring mathematical concepts--such as patterns, shape, spatial relationships, and measurement--leading them to spontaneously engage in mathematical thinking during play. Block play is one common example that engages…

  11. Shadow Play

    ERIC Educational Resources Information Center

    Ward, Alan

    1974-01-01

    Discusses the use of shadows to explain such scientific phenomena as umbra and penumbra, eclipses, day and night, seasons, and length of day. Indicates that shadow plays can serve to help the students in understanding more about light. (CC)

  12. Field trial of a pulsed limestone diversion well

    USGS Publications Warehouse

    Sibrell, Philip L.; Denholm, C.; Dunn, Margaret

    2013-01-01

    The use of limestone diversion wells to treat acid mine drainage (AMD) is well-known, but in many cases, acid neutralization is not as complete as would be desired. Reasons for this include channeling of the water through the limestone bed, and the slow reaction rate of the limestone gravel. A new approach to improve the performance of the diversion well was tested in the field at the Jennings Environmental Education Center, near Slippery Rock, PA. In this approach, a finer size distribution of limestone was used so as to allow fluidization of the limestone bed, thus eliminating channeling and increasing particle surface area for faster reaction rates. Also, water flow was regulated through the use of a dosing siphon, so that consistent fluidization of the limestone sand could be achieved. Testing began late in the summer of 2010, and continued through November of 2011. Initial system performance during the 2010 field season was good, with the production of net alkaline water, but hydraulic problems involving air release and limestone sand retention were observed. In the summer of 2011, a finer size of limestone sand was procured for use in the system. This material fluidized more readily, but acid neutralization tapered off after several days. Subsequent observations indicated that the hydraulics of the system was compromised by the formation of iron oxides in the pipe leading to the limestone bed, which affected water distribution and flow through the bed. Although results from the field trial were mixed, it is believed that without the formation of iron oxides and plugging of the pipe, better acid neutralization and treatment would have occurred. Further tests are being considered using a different hydraulic configuration for the limestone sand fluidized bed.

  13. Faunas of Mississippian oolitic limestones: Evidence from Salem Limestone, southern Indiana

    SciTech Connect

    Feldman, H.R. )

    1989-08-01

    In the Salem Limestone of southern Indiana, a correlation exists between the faunal assemblage and abundance of grains with superficial oolitic coatings in grainstones. Coarse, poorly sorted fossiliferous grainstones are dominated by an echinoderm-bryozoan-brachiopod assemblage of fossils with few mollusks. The presence of large whole fossils, such as articulated crinoid calyces, suggest limited transport of skeletal components. Grainstones, dominated by grains with superficial coatings, and foraminifers tend to contain a diverse mollusk-dominated assemblage of gastropods, bivalves, rostroconchs, chitins, and scaphopods. These fossils are disarticulated, but generally are not fragmented even though many of them are thin and delicate. Echinoderms, brachiopods, and bryozoans are repsented in the mollusk-domdinated assemblage almost exclusively by well-rounded and coated fragments, suggesting that they are not in situ. The presence of similar molluscan assemblages in other Mississippian coated-grain grainstones from Alabama (the Monteagle Limestone) and Oklahoma (an unnamed limestone) indicates that the assemblage may have been wide-spread. Mississippian grainstones dominated by oolites (which are not prominent in the Salem) generally have very few fossils.

  14. Exploring Young People's Civic Identities through Gamification: A Case Study of Finnish, Swedish and Norwegian Adolescents Playing a Social Simulation Game

    ERIC Educational Resources Information Center

    Eränpalo, Tommi

    2014-01-01

    This article is based on a case study where groups of Finnish, Swedish and Norwegian young people played a simulation game that stimulated collective deliberation on social issues. The game has been designed to provoke students to deliberate and to reflect on social problems relating to issues of citizenship and democracy. The analysis of the…

  15. Learning English Speaking through Mobile-Based Role-Plays: The Exploration of a Mobile English Language Learning App Called Engage

    ERIC Educational Resources Information Center

    Yang, Bowen; Zhou, Shijun; Ju, Weijie

    2013-01-01

    Engage is a new form of mobile application that connects students studying English with teachers in real-time via their smartphones. Students receive target language through preparation dialogues, and then apply it to a role-play with a teacher. The conceptualization and development of Engage follows the user-centred design approach; and the…

  16. Playing the Field(s): An Exploration of Change, Conformity and Conflict in Girls' Understandings of Gendered Physicality in Physical Education

    ERIC Educational Resources Information Center

    Hills, Laura A.

    2006-01-01

    This paper draws on data from a year-long ethnographic study of a group of 12- to 13-year-old girls that explored the processes through which they negotiated gendered physicality within the context of physical education. Bourdieu's concepts of habitus and social fields and McNay's extension of his work underpin a discussion of three contexts where…

  17. The properties of Portland cement-limestone-silica fume mortars

    SciTech Connect

    Zelic, J.; Krstulovic, R.; Tkalcec, E.; Krolo, P.

    2000-01-01

    This work has studied the influence of the combined action of silica fume and limestone or strength development, porosity, pore structure and morphological features in the system where 15 wt% of cement was substituted by finely ground limestone. Silica fume was added in amounts of 0, 2, 5, 8, 11 and 15 wt% on a cement basis, respectively. It has been established that limestone addition considerably increases the total porosity of mortars. However, if introduced together with silica fume up to 8 wt% of silica, porosity decreases. More than 8 wt% of silica increases the porosity again. The cement mortar containing 8 wt% of silica fume shows the highest compressive strength, the minimum value of the total porosity, and its pore size distribution curve shows a discontinuous pore structure. Limestone is taken up to the system and reacts with aluminate and ferrite phases from cement. Approximately 5 wt% is available for reaction after 120 days hydration of mortars containing no silica fume. The quantity of limestone incorporated is affected by the silica fume content. The replacement of Portland cement by 15 wt% of silica fume causes reduction both in the amount of cement and in the free CH content available for limestone chemical activity, and in this condition limestone acts only as a filler addition.

  18. Recovery and recycling of limestone in LEC flue gas desulfurization

    SciTech Connect

    Gardner, N.C.; Boo, J.Y.; Culver, L. )

    1992-09-01

    Prudich et. al. have proposed an attractive technology called Limestone Emission Control (LEC) for removing sulfur dioxide from flue gases. Beds of 1/8 inch wet limestone particles absorb the sulfur dioxide from the gases on contact. Sulfite and sulfate salts deposit on the surface of the particles; however, the gas never reaches the interior, limiting the limestone utilization to approximately 20% or less. The unreacted portion of the limestone can be recovered by mechanical grinding and recycling, enabling high overall sorbent utilization. Favorable economics are derived from small equipment, simplicity, and low sorbent costs. This project is a wet method for grinding and recovering the spent limestone from the LEC process, utilizing an impeller fluidizer, a new type of slurry processor. It consists of a cylindrical vessel with an impeller at one end. The impeller, driven at high rpm, concentrates the gravel size limestone in a rotating torus at the top of the cylinder, where the coating is abraded off by particle-particle impaction. The impeller generates sufficient pressure head to serve as a slurry pump. It combines the operation of wet grinding, washing, and transporting the spent and recovered limestone as an aqueous slurry. The fluidizer may be advantageous over dry grinding in the aspects of sharpness of separation, transport convenience, equipment erosion, and sorption bed cementation.

  19. Geology of Vanport limestone (Pennsylvanian) in Elk County, Pennsylvania

    SciTech Connect

    Kuntz, T.J.

    1987-09-01

    The northernmost exposures of the Vanport limestone appear in Elk and southern McKean Counties, Pennsylvania. The Vanport limestone is structurally preserved in N45/sup 0/-50/sup 0/E trending synclinal folds. Surface exposures are almost all incomplete due to erosion. Drill-hole data assisted in defining areas of nondeposition within Elk County, variations in thickness, and erosional loss by channeling. The Vanport limestone thins to the southeast within Elk County and probably changes from limestone to a shaly limestone (transition zone) and then to shale. Analysis of 70 limestone samples indicated an average insoluble-residue content of 11.4%. The insoluble residue, mainly clay, increases toward the southeast, the direction of paleoshoreline and source of terrigenous sediments. A lack of quartz grains suggests a lack of detrital input from the source area. A study of the vertical variation of the total insoluble-residue content displayed an increase at the bottoms and tops of the stratigraphic section, mirroring the transgressive-regressive phases of the Vanport sea. The majority of allochems were skeletal material in a micritic matrix. Most abundant were mollusks, followed by forams, brachiopods, echinoderms, ostracods, and bryozoans. Composita brachiopods and pseudopunctate and/or punctate brachiopods inhabited offshore stillstand and nearshore transgressive-regressive environments, respectively. Other fossil assemblages displayed spatial and temporal variation. A darker matrix color occurred in stratigraphic sections closer to the paleoshoreline, due to higher clay and organic content. More offshore stratigraphic sections of the limestone were noticeably lighter in color.

  20. United Arab Emirates limestones: impact of petrography on thermal behavior

    NASA Astrophysics Data System (ADS)

    Alaabed, Sulaiman; Soltan, Abdel Monem; Abdelghany, Osman; Amin, Bahaa Eldin Mahmoud; El Tokhi, Mohamed; Khaleel, Abbas; Musalim, Abdullah

    2014-12-01

    The thermal behavior of selected limestones from representative localities of the United Arab Emirates is investigated for their suitability for soft-burnt lime production. The limestone samples were collected from the Ghalilah, Musandam, Shauiba, Muthaymimah, Dammam and Asmari formations. The samples were characterized for petrography, mineral and chemical composition, together with physico-mechanical characteristics. Investigative methods included transmitted light microscopy (TLM), cathodoluminescence (CLM) and scanning electron microscopy (SEM), as well as X-ray micro-tomography (μ-CT), XRD, XRF and Archimedes method. The limestone samples were fired in an electrical muffle furnace for 0.25, 0.5, 1 and 2 hours at 800, 900, 1,000 and 1,100 °C. After firing the lime grains were tested to determine their hydration rate and microfabric. The Ghalilah and Musandam limes show the lowest and highest maximum hydration rates, respectively, due mainly to the impure nature of the former, and the smaller lime crystallites and dominance of post-calcination micro-cracks of the latter. The Dammam and Asmari limes preserve a "ghost" microfabric of the original limestone. Higher allochem contents impose lower activation energy requirements for calcination, which implies earlier calcination of the allochems. The Musandam, Shauiba and Muthaymimah limestones may be useful for the production of reactive soft-burnt lime under the applied firing conditions, however, the Dammam and Asmari limestones need more advanced calcination conditions than the applied ones. The Ghalilah limestone was found to be unsuitable for the production of lime.

  1. Sweet Play

    ERIC Educational Resources Information Center

    Leung, Shuk-kwan S.; Lo, Jane-Jane

    2010-01-01

    This article features Sweet play math, a "math by the month" activity that involves decorating and making sugar cubes. Teachers may want to substitute straws, paper squares, alphabet blocks, or such commercially made manipulatives as Unifix[R] cubes for the real sweets. Given no allergy concerns, teachers and students alike would enjoy some sweet…

  2. Game playing.

    PubMed

    Rosin, Christopher D

    2014-03-01

    Game playing has been a core domain of artificial intelligence research since the beginnings of the field. Game playing provides clearly defined arenas within which computational approaches can be readily compared to human expertise through head-to-head competition and other benchmarks. Game playing research has identified several simple core algorithms that provide successful foundations, with development focused on the challenges of defeating human experts in specific games. Key developments include minimax search in chess, machine learning from self-play in backgammon, and Monte Carlo tree search in Go. These approaches have generalized successfully to additional games. While computers have surpassed human expertise in a wide variety of games, open challenges remain and research focuses on identifying and developing new successful algorithmic foundations. WIREs Cogn Sci 2014, 5:193-205. doi: 10.1002/wcs.1278 CONFLICT OF INTEREST: The author has declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website. PMID:26304308

  3. A procedure to evaluate environmental rehabilitation in limestone quarries.

    PubMed

    Neri, Ana Claudia; Sánchez, Luis Enrique

    2010-11-01

    A procedure to evaluate mine rehabilitation practices during the operational phase was developed and validated. It is based on a comparison of actually observed or documented practices with internationally recommended best practices (BP). A set of 150 BP statements was derived from international guides in order to establish the benchmark. The statements are arranged in six rehabilitation programs under three categories: (1) planning (2) operational and (3) management, corresponding to the adoption of the plan-do-check-act management systems model to mine rehabilitation. The procedure consists of (i) performing technical inspections guided by a series of field forms containing BP statements; (ii) classifying evidences in five categories; and (iii) calculating conformity indexes and levels. For testing and calibration purposes, the procedure was applied to nine limestone quarries and conformity indexes were calculated for the rehabilitation programs in each quarry. Most quarries featured poor planning practices, operational practices reached high conformity levels in 50% of the cases and management practices scored moderate conformity. Despite all quarries being ISO 14001 certified, their management systems pay low attention to issues pertaining to land rehabilitation and biodiversity. The best results were achieved by a quarry whose expansion was recently submitted to the environmental impact assessment process, suggesting that public scrutiny may play a positive role in enhancing rehabilitation practices. Conformity indexes and levels can be used to chart the evolution of rehabilitation practices at regular intervals, to establish corporate goals and for communication with stakeholders. PMID:20630648

  4. Influence of water contained in porous limestone on corrosion

    NASA Astrophysics Data System (ADS)

    Kozłowski, R.; Hejda, A.; Cȩckiewicz, S.; Haber, J.

    The chemical degradation of porous limestone due to its reaction with sulphur dioxide was investigated by determining amounts and distributions of sulphur-containing corrosion products in samples collected from historic buildings. Water vapour adsorption equilibria have been determined for limestones of varying petrology, and correlated with sulphur dioxide uptakes measured in artificial weathering experiments. Out of several possible routes of the corrosive reaction, dissolution of sulphur dioxide in bulk water present in the stone may be related to the prevailing mechanism leading to stone deterioration. The bulk water may appear in the limestone as water condensed in the capillaries, or absorbed by hygroscopic salts.

  5. EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY PIT ('THE OLD PIT') WITH LEDGE PREPARED FOR LIMESTONE EXTRACTION. AN ELEVEN-HOLE SHOT WILL DISLODGE APPROXIMATELY 25,000 TONS OF LIMESTONE WHICH, AFTER LOADING AND CRUSHING, WILL BE USED FOR ROAD CONSTRUCTION. THE CALERA QUARRY IS ONE OF FOUR ACTIVE VULCAN MATERIALS COMPANY QUARRIES IN THE DISTRICT. VULCAN MATERIALS, A FORTUNE 500 FIRM, ESTABLISHED IN BIRMINGHAM IN 1906 AS BIRMINGHAM SLAG COMPANY, VULCAN MATERIALS IS THE NATION'S FOREMOST PRODUCER OF CONSTRUCTION AGGREGATE AND A LEADING CHEMICALS MANUFACTURER. - Vulcan Material Company, Calera Quarry, 1614 Highway 84, Calera, Shelby County, AL

  6. EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY PIT ("THE OLD PIT") WITH LEDGE PREPARED FOR LIMESTONE EXTRACTION. AN ELEVEN-HOLE SHOT WILL DISLODGE APPROXIMATELY 25,000 TONS OF LIMESTONE WHICH, AFTER LOADING AND CRUSHING, WILL BE USED FOR ROAD CONSTRUCTION. THE CALERA QUARRY IS ONE OF FOUR ACTIVE VULCAN MATERIALS COMPANY QUARRIES IN THE DISTRICT. VULCAN MATERIALS, A FORTUNE 500 FIRM, ESTABLISHED IN BIRMINGHAM IN 1906 AS BIRMINGHAM SLAG COMPANY, VULCAN MATERIALS IS THE NATION'S FOREMOST PRODUCER OF CONSTRUCTION AGGREGATE AND A LEADING CHEMICALS MANUFACTURER - Vulcan Material Company, Calera Quarry, 1614 Highway 84, Calera, Shelby County, AL

  7. Silica and dolomite paragenesis in crinoidal limestones

    SciTech Connect

    Lyons, T.W.; Vahrenkamp, V.C.

    1985-01-01

    The intimate association of silica and dolomite in crinoid fragments is a commonly observed phenomenon in chert-rich carbonates of all ages. An investigation of this silica/dolomite association in some Phanerozoic examples from North America has revealed a striking cause and effect relationship between silicification and dolomitization which closely parallels the findings of Jacka (1974). Based on detailed petrographic analysis of crinoidal limestones, it is argued that dolomite forms concomitant with, and as a product of, the replacement of calcium carbonate by silica. Two possible mechanisms exist regarding the observed paragenesis: 1) silica replacement of high magnesian-calcite (HMC) mobilizes and redistributes Mg/sup 2 +/ resulting in the simultaneous partial dolomitization of the remaining HMC; this dolomite is then selectively preserved or partially replaced during continued silicification; 2) initially, metastable opal-CT being derived from the crinoid host; during the ensuing opal-CT to quartz transformation, Mg/sup 2 +/ is liberated and causes local dolomitization. Petrographic observations suggest that a significant volume of replacement dolomite can be generated from a local source of Mg/sup 2 +/, here the HMC crinoid host. Dolomitization occurred during early diagenesis prior to the stabilization of HMC to LMC possibly in a mixed-water environment. Low temperature natural co-precipitation of quartz and dolomite may provide an alternative mechanism whereby the oxygen isotopic fractionation between water and dolomite could be calculated.

  8. Residual CO2 trapping in Indiana limestone.

    PubMed

    El-Maghraby, Rehab M; Blunt, Martin J

    2013-01-01

    We performed core flooding experiments on Indiana limestone using the porous plate method to measure the amount of trapped CO(2) at a temperature of 50 °C and two pressures: 4.2 and 9 MPa. Brine was mixed with CO(2) for equilibration, then the mixture was circulated through a sacrificial core. Porosity and permeability tests conducted before and after 884 h of continuous core flooding confirmed negligible dissolution. A trapping curve for supercritical (sc)CO(2) in Indiana showing the relationship between the initial and residual CO(2) saturations was measured and compared with that of gaseous CO(2). The results were also compared with scCO(2) trapping in Berea sandstone at the same conditions. A scCO(2) residual trapping end point of 23.7% was observed, indicating slightly less trapping of scCO(2) in Indiana carbonates than in Berea sandstone. There is less trapping for gaseous CO(2) (end point of 18.8%). The system appears to be more water-wet under scCO(2) conditions, which is different from the trend observed in Berea; we hypothesize that this is due to the greater concentration of Ca(2+) in brine at higher pressure. Our work indicates that capillary trapping could contribute to the immobilization of CO(2) in carbonate aquifers.

  9. Acid mine treatment with open limestone channels

    SciTech Connect

    Ziemkiewicz, P.F.; Brant, D.L.; Skousen, J.G.

    1996-12-31

    Acid mine drainage (AMD) is often associated with mining of pyritic coal and metal deposits. Typical AMD associated with coal mines in the eastern US can have acidity and iron concentrations ranging from the teens to the thousands of mg/l. Aluminum and manganese can be present in concentrations ranging from zero to the low hundreds of mg/l. Much attention has been devoted to developing inexpensive, limestone (LS)-based systems for treating AMID with little or no maintenance. However, LS tends to coat with metal hydroxides when exposed to AMID in an oxidized state, a process known as {open_quotes}armoring{close_quotes}. It is generally assumed that once armored, LS ceases to neutralize acid. Another problem is that the hydroxides tend to settle into plug the pore spaces in LS beds forcing water to move around rather than through the LS. While both are caused by the precipitation of metal hydroxides, armoring and plugging are two different problems. Plugging of LS pores can be avoided by maintaining a high flushing rate through the LS bed. Armoring, however, occurs regardless of water velocity. This study investigated the influence of armoring on LS solubility and the implications of armoring and plugging on the construction of open (oxidizing) LS channels for treating AMD. We evaluated the AMID treatment performance of armored and unarmored LS in oxidizing environments both in laboratory and field studies.

  10. The conservation of Britain's limestone cave resource

    NASA Astrophysics Data System (ADS)

    Hardwick, P.; Gunn, J.

    1996-10-01

    Limestone caves are an important scientific and recreational resource in Britain. During the mid- to late 1970s, cavers and statutory conservation bodies cooperated in a review of cave resources which resulted in the designation of 48 caves or cave areas as Sites of Special Scientific Interest (SSSI). During the same period, the Wildlife and Countryside Act 1981 was introduced to provide more effective planning controls on activities such as agriculture carried out within SSSI boundaries. In one case, at Priddy in the Mendip Hills of Somerset, landowners prevented access to a number of caves in protest over the new, tougher restrictions on agriculture. Faced with the closure, and perceiving that their recreational use of caves might also be controlled, local cavers joined the landowners in opposing the proposals for SSSI designation. As a result the proposals were reviewed, three caves were excluded from the site and controls on the remaining area were relaxed. The case emphasized a need for an effective system to take account of all factors affecting cave conservation, a need which has led to a more constructive dialogue between nature conservation bodies, caver organizations and other interested parties.

  11. LUTETIAN LIMESTONES IN THE PARIS REGION: PETROGRAPHIC AND COMPOSITIONAL EXAMINATION

    SciTech Connect

    BLANC,A.; HOLMES,L.L.; HARBOTTLE,G.

    1998-06-11

    Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific-stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemist whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries.

  12. Lutetian limestones in the Paris region: Petrographic and compositional examination

    SciTech Connect

    Blanc, A.; Holmes, L.L.; Harbottle, G.

    1998-12-31

    Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists have investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemistry whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries.

  13. 1. SOUTH FACADE. CONSTRUCTED (ca. 1895) OF INDIGENOUS LIMESTONE AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. SOUTH FACADE. CONSTRUCTED (ca. 1895) OF INDIGENOUS LIMESTONE AND USED AS LOCKPORTS CENTRAL HIGH SCHOOL FOR MORE THAN SIXTY YEARS. - Lockport Historic District, Central High School, Lockport, Will County, IL

  14. Limestone - A Crucial and Versatile Industrial Mineral Commodity

    USGS Publications Warehouse

    Bliss, James D.; Hayes, Timothy S.; Orris, Greta J.

    2008-01-01

    Limestone, as used by the minerals industry, is any rock composed mostly of calcium carbonate (CaCO3). Although limestone is common in many parts of the United States, it is critically absent from some. Limestone is used to produce Portland cement, as aggregate in concrete and asphalt, and in an enormous array of other products, making it a truly versatile commodity. Portland cement is essential to the building industry, but despite our Nation's abundance of limestone, there have been cement shortages in recent years. These have been caused in part by a need to find new areas suitable for quarrying operations. To help manage our Nation's resources of such essential mineral commodities, the U.S. Geological Survey (USGS) provides crucial data and scientific information to industry, policymakers, and the public.

  15. Major Oil Plays In Utah And Vicinity

    SciTech Connect

    Thomas Chidsey

    2007-12-31

    Jurassic Twin Creek Limestone, or a low-permeability zone at the top of the Nugget. The Nugget Sandstone thrust belt play is divided into three subplays: (1) Absaroka thrust - Mesozoic-cored shallow structures, (2) Absaroka thrust - Mesozoic-cored deep structures, and (3) Absaroka thrust - Paleozoic-cored shallow structures. Both of the Mesozoic-cored structures subplays represent a linear, hanging wall, ramp anticline parallel to the leading edge of the Absaroka thrust. Fields in the shallow Mesozoic subplay produce crude oil and associated gas; fields in the deep subplay produce retrograde condensate. The Paleozoic-cored structures subplay is located immediately west of the Mesozoic-cored structures subplays. It represents a very continuous and linear, hanging wall, ramp anticline where the Nugget is truncated against a thrust splay. Fields in this subplay produce nonassociated gas and condensate. Traps in these subplays consist of long, narrow, doubly plunging anticlines. Prospective drilling targets are delineated using high-quality, two-dimensional and three-dimensional seismic data, forward modeling/visualization tools, and other state-of-the-art techniques. Future Nugget Sandstone exploration could focus on more structurally complex and subtle, thrust-related traps. Nugget structures may be present beneath the leading edge of the Hogsback thrust and North Flank fault of the Uinta uplift. The Jurassic Twin Creek Limestone play in the Utah/Wyoming thrust belt province has produced over 15 million barrels (2.4 million m{sup 3}) of oil and 93 billion cubic feet (2.6 billion m{sup 3}) of gas. Traps form on discrete subsidiary closures along major ramp anticlines where the low-porosity Twin Creek is extensively fractured. Hydrocarbons in Twin Creek reservoirs were generated from subthrust Cretaceous source rocks. The seals for the producing horizons are overlying argillaceous and clastic beds, and non-fractured units within the Twin Creek. The Twin Creek Limestone thrust

  16. Trapping models for the Lower Silurian Medina Sandstone Group - A comparison of trapping styles and exploration methodology for both deep and shallow medina plays in the Appalachian basin

    SciTech Connect

    Zagorski, W.A. )

    1991-08-01

    The Lower Silurian Medina Sandstone Group has been a major oil and gas producer in the Appalachian basin since the late 1800s and remains a primary objective in parts of New York, Ohio, and Pennsylvania. Although classified as a stratigraphic trap, production from the Medina is obtained from a wide variety of trapping conditions ranging from pure stratigraphic to structural stratigraphic in the shallower producing areas of the Medina to deep basin (i.e., Elmworth field, western Canada) trapping in the deeper producing regions of strategies must be employed for optimum prospect development and maximum economic success ratios. Several producing areas of the Medina are presented to compare and contrast these various trapping mechanisms together with suggested exploration models applicable to each trap type.

  17. Thermo-Hydro-Mechanical-Chemical Coupled Modeling of Geothermal Doublet Systems in Limestones

    NASA Astrophysics Data System (ADS)

    Rühaak, Wolfram; Pei, Liang; Heldmann, Claus-Dieter; Bartels, Jörn; Sass, Ingo

    2015-04-01

    Limestone aquifers in Southern Germany have been used within the last decade very successfully for geothermal heating and - to a lesser extent - for power generation. As an example the region around Munich has been extensively explored. While the extent of usage of this reservoir is increasing there is also an increased interest in better understanding of the reservoir properties and its change in the course of operation. For instance, the observed production and injection pressures are partly hard to explain. They may be related to mechanical or chemical processes, or both. Based on extensive data of outcrop studies and drillings, a data-base for the relevant physical properties of the respective limestones has been complied. The data include thermal conductivity, density, specific heat capacity, permeability, as well as mechanical properties like thermal expansion coefficient and elasticity modules. By using the hydro-thermo-chemical simulator FEFLOW together with an extension for thermo- and hydro-mechanical coupling the relevant processes are studied and compared with observed data. Conclusions for an optimized operation of geothermal systems in limestones are given and discussed.

  18. Influence of limestone on the hydration of Portland cements

    SciTech Connect

    Lothenbach, Barbara Le Saout, Gwenn; Gallucci, Emmanuel; Scrivener, Karen

    2008-06-15

    The influence of the presence of limestone on the hydration of Portland cement was investigated. Blending of Portland cement with limestone was found to influence the hydrate assemblage of the hydrated cement. Thermodynamic calculations as well as experimental observations indicated that in the presence of limestone, monocarbonate instead of monosulfate was stable. Thermodynamic modelling showed that the stabilisation of monocarbonate in the presence of limestone indirectly stabilised ettringite leading to a corresponding increase of the total volume of the hydrate phase and a decrease of porosity. The measured difference in porosity between the 'limestone-free' cement, which contained less than 0.3% CO{sub 2}, and a cement containing 4% limestone, however, was much smaller than calculated. Coupling of thermodynamic modelling with a set of kinetic equations which described the dissolution of the clinker, predicted quantitatively the amount of hydrates. The quantities of ettringite, portlandite and amorphous phase as determined by TGA and XRD agreed well with the calculated amounts of these phases after different periods of time. The findings in this paper show that changes in the bulk composition of hydrating cements can be followed by coupled thermodynamic models. Comparison between experimental and modelled data helps to understand in more detail the dominating processes during cement hydration.

  19. Playing the role of a science student: Exploring the meaning of the science student role and its relationship to students' identification in science

    NASA Astrophysics Data System (ADS)

    Shanahan, Marie-Claire

    Learning and succeeding in school is a process that involves the whole person and is situated within the social context of the school and classroom. As science educators, this means exploring how and why individuals come to see themselves as science students. To examine this process, I have used a framework of role identity theory, which takes the perspective that in all situations there are roles that carry with them behavioural and attitudinal expectations. Individuals develop role identities when they are able to match their self-perceptions with the meanings of the role. This study explores the meaning of the science student role and its impact on student identification in science using a three-phase, mixed-methods design. In Phase 1, an exploratory qualitative phase, student responses ( n = 95) were collected through open-ended questionnaires and follow-up interviews and used to create a framework for understanding the role and the expectations associated with it. Phase 2 used this framework to create a questionnaire asking students (n = 129) to compare the expectations in science to those in other classes. Phase 3 took the role components from Phase 2 and asked students (n = 292) to rate themselves and ideal science students with respect to these expectations. Regression was used to understand how students' comparisons of themselves to the role related to their definitions of themselves as science students and to their future plans in science. The results suggest a clearly defined science student role that is dominated by traditional understandings of scientific attitudes. The Phase 2 results suggest that the expectations can be represented by four subscales: intelligence, scientific mindedness, scientific skill, and appropriate behaviour. The results of Phase 3 demonstrate that student ratings of themselves as intelligent and scientifically minded were strong predictors of their self-reported identification with science, accounting for almost half of the

  20. Attrition of limestone by impact loading in fluidized beds

    SciTech Connect

    Fabrizio Scala; Fabio Montagnaro; Piero Salatino

    2007-09-15

    The present study addresses limestone attrition and fragmentation associated with impact loading, a process which may occur extensively in various regions of fluidized bed (FB) combustors/gasifiers, primarily the jetting region of the bottom bed, the exit region of the riser, and the cyclone. An experimental protocol for the characterization of the propensity of limestone to undergo attrition/fragmentation by impact loading is reported. The application of the protocol is demonstrated with reference to an Italian limestone whose primary fragmentation and attrition by surface wear have already been characterized in previous studies. The experimental procedure is based on the characterization of the amount and particle size distribution of the debris generated upon the impact of samples of sorbent particles against a target. Experiments were carried out at a range of particle impact velocities between 10 and 45 m/s, consistent with jet velocities corresponding to typical pressure drops across FB gas distributors. The protocol has been applied to either raw or preprocessed limestone samples. In particular, the effect of calcination, sulfation, and calcination/recarbonation cycles on the impact damage suffered by sorbent particles has been assessed. The measurement of particle voidage and pore size distribution by mercury intrusion was also accomplished to correlate fragmentation with the structural properties of the sorbent samples. Fragmentation by impact loading of the limestone is significant. Lime displays the largest propensity to undergo impact damage, followed by the sorbent sulfated to exhaustion, the recarbonated sorbent, and the raw limestone. Fragmentation of the raw limestone and of the sulfated lime follows a pattern typical of the failure of brittle materials. The fragmentation behavior of lime and recarbonated lime better conforms to a disintegration failure mode, with an extensive generation of very fine fragments. 27 refs., 9 figs. 1 tab.

  1. Mid-continent natural gas reservoirs and plays

    SciTech Connect

    Bebout, D.G. )

    1993-09-01

    Natural gas reservoirs of the mid-continent states of Oklahoma, Kansas, and Arkansas (northern part) have produced 103 trillion cubic ft (tcf) of natural gas. Oklahoma has produced the most, having a cumulative production of 71 tcf. The major reservoirs (those that have produced more than 10 billion ft[sup 3]) have been identified and organized into 28 plays based on geologic age, lithology, and depositional environment. The Atlas of Major Midcontinent Gas Reservoirs, published in 1993, provides the documentation for these plays. This atlas was a collaborative effort of the Gas Research Institute; Bureau of Economic Geology. The University of Texas at Austin; Arkansas Geological Commission; Kansas Geological survey; and Oklahoma Geological Survey. Total cumulative production for 530 major reservoirs is 66 tcf associated and nonassociated gas. Oklahoma has the highest production with 39 tcf from 390 major reservoirs, followed by Kansas with 26 tcf from 105 major reservoirs. Most of the mid-continent production is from Pennsylvanian (46%) and Permian (41%) reservoirs; Mississippian reservoirs account for 10% production, and lower Paleozoic reservoirs, 3%. The largest play by far is the Wolfcampian Shallow Shelf Carbonate-Hugoton Embayment play with 25 tcf cumulative production, most of which is from the Hugoton and Panoma fields in Kansas and Guymon-Hugoton gas area in Oklahoma. A total of 53% of the mid-continent gas production is from dolostone and limestone reservoirs; 39% is from sandstone reservoirs. The remaining 8% is from chert conglomerate and granite-wash reservoirs. Geologically based plays established from the distribution of major gas reservoirs provide important support for the extension of productive trends, application of new resource technology to more efficient field development, and further exploration in the mid-continent region.

  2. Modifying the properties of finely ground limestone by tumbling granulation

    NASA Astrophysics Data System (ADS)

    Macho, Oliver; Eckert, Maroš; Tomášová, Barbora; Peciar, Peter; Ščasný, Martin; Fekete, Roman; Peciar, Marián

    2016-06-01

    Calcium carbonate in the form of finely ground limestone is a material that has found its application in a wide range of industries, in the chemical, rubber, agricultural, and paper industries, is used for desulfurization of boilers and other. In civil engineering, ground limestone is used for the production of building materials, plaster and mortar mixtures, as a filler in concrete mixtures, in road construction, and as an essential component of mastic asphalt. This paper deals with examining the modification of the properties of finely ground limestone by the tumbling agglomeration method. It has been shown that the components of concrete with a round grain have a positive effect on the pumping of concrete in comparison with an elongated grain or the rough surface of crushed stone. The experiments will be carried out on a granulation plate using a variety of granulation liquid. The agglomerates and their properties were compared with untreated finely ground limestone, with a focus on detecting changes in compressibility, density and particle size. The output of this paper is a description and graphical representation of the changes in the properties of ground limestone before and after the agglomeration process.

  3. Novel Hydroxyapatite Coatings for the Conservation of Marble and Limestone

    NASA Astrophysics Data System (ADS)

    Naidu, Sonia

    Marble and limestone are calcite-based materials used in the construction of various structures, many of which have significant artistic and architectural value. Unfortunately, due to calcite's high dissolution rate, these stones are susceptible to chemically-induced weathering in nature. Limestone, due to its inherent porosity, also faces other environmental weathering processes that cause weakening from disintegration at grain boundaries. The treatments presently available are all deficient in one way or another. The aim of this work is to examine the feasibility of using hydroxyapatite (HAP) as a novel protective coating for marble and limestone, with two goals: i) to reduce acid corrosion of marble and ii) to consolidate physically weathered limestone. The motivation for using HAP is its low dissolution rate and structural compatibility with calcite. Mild, wet chemical synthesis routes, in which inorganic phosphate-based solutions were reacted with marble and limestone, alone and with other precursors, were used to produce HAP films. Film nucleation, growth and phase evolution were studied on marble to understand film formation and determine the optimal synthesis route. An acid resistance test was developed to investigate the attack mechanism on marble and quantify the efficacy of HAP-based coatings. Film nucleation and growth were dependent on substrate surface roughness and increased with calcium and carbonate salt additions during synthesis. Acid attack on marble occurred via simultaneous dissolution at grain boundaries, twin boundaries and grain surfaces. HAP provided intermediate protection against acid attack, when compared to two conventional treatments. Its ability to protect the stone from acid was not as significant as predicted from dissolution kinetics and this was attributed to incomplete coverage and residual porosity within the film, arising from its flake-like crystal growth habit, which enabled acid to access the underlying substrate. The

  4. The Ançã limestones, Coimbra, Portugal

    NASA Astrophysics Data System (ADS)

    Quinta-Ferreira, Mário; Gil Catarino, Lídia; Delgado Rodrigues, José

    2016-04-01

    Ançã is located in the Lusitanian Basin (western Meso-Cenozoic sedimentary basin), in the municipality of Cantanhede, close to Coimbra, Portugal. This constitutes the northernmost Dogger (Bajocian) limestone sequence in Portugal. The use of the Ançã limestones is documented since the Roman occupation of the Iberian Peninsula. It was used for the construction of houses, palaces, churches, fine sculptures, carving, paving and for the production of lime. These limestones vary from white and very soft varieties, with very high porosity used for sculpture and carving to white and hard varieties used for masonry and as aggregates and to white to bluish with low porosity and high strength varieties, mainly used for paving. The softer and whiter variety is worldwide known as Ançã Stone (Pedra de Ançã) exhibiting a porosity of 26-29 %. It became famous after being largely used by Coimbra most famous Renaissance sculptors like João de Ruão and Nicolau de Chanterenne. The Pedra de Ançã was used mainly in the region of Coimbra, but also in several other places in Portugal, in Santiago de Compostela, Spain, and Brazil. Some examples of heritage in Coimbra using the Pedra de Ançã are the renaissance portal of the Saint Cross Church, the tombs of the first two Portuguese kings located in this church, the altar of the Saint Cross Church or of the Old Cathedral, or in sculptures at the University of Coimbra. It is quite prone to deteriorate when exposed to atmospheric agents and to soluble salts, mainly due to its high porosity. Deteriorated surfaces needing treatment constitute difficult conservation problems, especially when consolidation and protection treatments are required. The less porous varieties of the Ançã limestones (< 20 % porosity) were mainly used for masonry, paving and production of lime. The royal Palace of Buçaco is a remarkable masonry building constructed at the end of the XIX century with the less porous varieties of the Ançã limestones

  5. Leaching of clay minerals in a limestone environment

    USGS Publications Warehouse

    Carroll, D.; Starkey, H.C.

    1959-01-01

    Water saturated with CO2 at about 25??C was percolated through mixed beds of limestone or marble fragments and montmorillonite, "illite" and kaolinite in polyethylene tubes for six and fortyfive complete runs. The leachates were analysed for SiO2, A12O3 and Fe2O3, but only SiO2 was found. The minerals lost SiO2 in this order: montmorillonite > kaolinite > "illite". The differential removal of SiO2 during the short period of these experiments suggests a mechanism for the accumulation of bauxite deposits associated with limestones. ?? 1959.

  6. Limestone calcination with CO{sub 2} capture (III): characteristics of coal combustion during limestone decomposition

    SciTech Connect

    Yin Wang; Shiying Lin; Yoshizo Suzuki

    2009-05-15

    In this study, the combustion characteristics of coal in CO{sub 2}/O{sub 2} and steam/CO{sub 2}/O{sub 2} atmospheres were investigated during limestone decomposition in a continuously operating fluidized bed reactor for CO{sub 2} capture. The results show that the variations and concentrations of CO, CH{sub 4}, and H{sub 2} in the exhaust gas of the reactor in the steam/CO{sub 2}/O{sub 2} atmosphere were smaller than those in the CO{sub 2}/O{sub 2} atmosphere. Because of steam dilution, the CO{sub 2} concentration in the bed was lower in the steam/CO{sub 2}/O{sub 2} atmosphere than that in the CO{sub 2}/O{sub 2} atmosphere, and the effect of differential pressure variation on limestone decomposition in the fluidized bed was less pronounced in the steam/CO{sub 2}/O{sub 2} atmosphere than that in the CO{sub 2}/O{sub 2} atmosphere. Additionally, N{sub 2}O emission was detected only in the CO{sub 2}/O{sub 2} atmosphere, and the conversion of N to NO in the steam dilution atmosphere was of a smaller magnitude than that observed in the CO{sub 2}/O{sub 2} atmosphere. We also found that the conversion of S to SO{sub 2} in the steam/CO{sub 2}/O{sub 2} atmosphere was lower than that observed in the CO{sub 2}/O{sub 2} atmosphere. The contents of sulfur, SiO{sub 2}, and Al{sub 2}O{sub 3} were much higher in solid samples located in the cyclone than in the overflow holder in both steam/CO{sub 2}/O{sub 2} and CO{sub 2}/O{sub 2} atmospheres. Finally, the hydration and carbonation reactivities of CaO produced in the steam/CO{sub 2}/O{sub 2} atmosphere were better than those produced in the CO{sub 2}/O{sub 2} atmosphere. 13 refs., 14 figs., 3 tabs.

  7. Depositional and tectonic interpretation of limestone insoluble residues from modern and ancient carbonate rocks, Caribbean and southeastern United States

    SciTech Connect

    Isphording, W.C.; Bundy, M.E.; George, S.M.

    1995-10-01

    Mineral compositions have long been used as indicators of the provenance and tectonic setting of source rocks for sandstones and shales. Extraction of the same information from limestones is less common because of the general paucity of the non-carbonate phase and the greater processing time that is required to concentrate the frequently encountered small quantities of detrital (and authigenic) minerals. The insoluble component, however, contains a great deal of valuable information and should not be ignored. The clays and other insoluble minerals in limestones from southeastern United States and the Caribbean region, for example, clearly reflect the volcanic activity that was associated with formation of the Mid-Atlantic Ridge rift system and the opening of the Atlantic Ocean and Gulf of Mexico. Similarly, major periods of orogeny during the Paleozoic and Mesozoic have left their signature, even in carbonate rocks that originated far from the sites where uplift was taking place. In other cases, the insoluble residue component clearly manifests periods of quiescence in adjacent land areas or testifies to the airborne transport of insoluble components from sources as far distant as the Saharan Desert of Africa. Similarly, insoluble components have convincingly shown that the origin of the extensive bauxite deposits found in Jamaican limestones are the result of alteration of interbedded volcanic ash units and have not resulted from accumulation of the detritus in the limestones. Residue analysis in Gulf Coast limestones can be successfully used for subsurface identification and correlation of carbonate units in the exploration for hydrocarbons, to reconstruct sedimentary environments, to identify missing sections, and to identify paraconformable realtionships between adjacent carbonate units that are otherwise similar in appearance. The latter is especially useful where extensive recrystallization has taken place and fossils have been destroyed.

  8. The Solnhofen Limestone: A stony heritage of many uses

    NASA Astrophysics Data System (ADS)

    Kölbl-Ebert, Martina; Kramar, Sabina; Cooper, Barry J.

    2016-04-01

    High above the valley of the River Altmühl (Bavaria, Germany), between Solnhofen to the west and Kelheim to the east, numerous quarries give access to thinly plated limestone from the Upper Jurassic, some 150 million years before the present. The main quarry areas lie around the town of Eichstätt and between the villages of Solnhofen, Langenaltheim and Mörnsheim. Here limestone slabs have been quarried for several hundred years, some even in Roman times. Solnhofen Limestone is famous worldwide; not only because it is a beautiful building stone of high quality, but also because of the exceptionally well-preserved fossils it contains -among them the early bird Archaeopteryx. The quarry industry between Solnhofen and Eichstätt has shaped a cultural landscape, with old and new quarries sunk into the plain and numerous spoil heaps rising above it, for the rock is not all economically useful. But many of the spoil heaps and the old quarries are environmentally protected as they provide a habitat for some rare plants and animals. It is not necessary to cut the Solnhofen Limestone with a saw: it is split by hand into thin and even slabs or sheets which are used for flagstones and wall covers, which since centuries are sold world-wide. Locally it also serves as roof tiles for traditional houses. Thick slabs of especially fine quality may be found near Solnhofen and Mörnsheim and are used for lithography printing.

  9. Detail view to show one of the limestone relief panels ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view to show one of the limestone relief panels depicting one of the agencies of the Commerce Department, here the Lighthouse Service - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  10. Soil respiration patterns and controls in limestone cedar glades

    USGS Publications Warehouse

    Cartwright, Jennifer M.; Hui, Dafeng

    2015-01-01

    Soil depth, SOM, and vegetation cover were important drivers of Rs in limestone cedar glades. Seasonal Rs patterns reflected those for mesic temperate grasslands more than for semi-arid ecosystems, in that Rs primarily tracked temperature for most of the year.

  11. View of the main entrance with basrelief limestone panel designed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the main entrance with bas-relief limestone panel designed by C. Paul Jennwein upon which is inscribed "Lege Atque Ordine Omnia Fiunt" (translated as by law and order all is accomplished) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  12. The influence of additives on rheological properties of limestone slurry

    NASA Astrophysics Data System (ADS)

    Jaworska, B.; Bartosik, A.

    2014-08-01

    Limestone slurry appears in the lime production process as the result of rinsing the processed material. It consists of particles with diameter smaller than 2 mm and the water that is a carrier of solid fraction. Slurry is directed to the settling tank, where the solid phase sediments and the excess water through the transfer system is recovered for re-circulation. Collected at the bottom of the tank sludge is deposited in a landfill located on the premises. Rheological properties of limestone slurry hinder its further free transport in the pipeline due to generated flow resistance. To improve this state of affairs, chemical treatment of drilling fluid, could be applied, of which the main task is to give the slurry properties suitable for the conditions encountered in hydrotransport. This treatment consists of applying chemical additives to slurry in sufficient quantity. Such additives are called as deflocculants or thinners or dispersants, and are chemical compounds which added to aqueous solution are intended to push away suspended particles from each other. The paper presents the results of research allowing reduction of shear stress in limestone slurry. Results demonstrate rheological properties of limestone slurry with and without the addition of modified substances which causes decrease of slurry viscosity, and as a consequence slurry shear stress for adopted shear rate. Achieving the desired effects increases the degree of dispersion of the solid phase suspended in the carrier liquid and improving its ability to smooth flow with decreased friction.

  13. Curved limestone wall at east end of rail yard. Note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Curved limestone wall at east end of rail yard. Note cut off valves at base of stump in right foreground, and utility tunnel in middle distance, superindent's house at right, looking NW. - Grand Canyon Village Utilities, Grand Canyon National Park, Grand Canyon Village, Coconino County, AZ

  14. Limestone: high-throughput candidate phenotype generation via tensor factorization.

    PubMed

    Ho, Joyce C; Ghosh, Joydeep; Steinhubl, Steve R; Stewart, Walter F; Denny, Joshua C; Malin, Bradley A; Sun, Jimeng

    2014-12-01

    The rapidly increasing availability of electronic health records (EHRs) from multiple heterogeneous sources has spearheaded the adoption of data-driven approaches for improved clinical research, decision making, prognosis, and patient management. Unfortunately, EHR data do not always directly and reliably map to medical concepts that clinical researchers need or use. Some recent studies have focused on EHR-derived phenotyping, which aims at mapping the EHR data to specific medical concepts; however, most of these approaches require labor intensive supervision from experienced clinical professionals. Furthermore, existing approaches are often disease-centric and specialized to the idiosyncrasies of the information technology and/or business practices of a single healthcare organization. In this paper, we propose Limestone, a nonnegative tensor factorization method to derive phenotype candidates with virtually no human supervision. Limestone represents the data source interactions naturally using tensors (a generalization of matrices). In particular, we investigate the interaction of diagnoses and medications among patients. The resulting tensor factors are reported as phenotype candidates that automatically reveal patient clusters on specific diagnoses and medications. Using the proposed method, multiple phenotypes can be identified simultaneously from data. We demonstrate the capability of Limestone on a cohort of 31,815 patient records from the Geisinger Health System. The dataset spans 7years of longitudinal patient records and was initially constructed for a heart failure onset prediction study. Our experiments demonstrate the robustness, stability, and the conciseness of Limestone-derived phenotypes. Our results show that using only 40 phenotypes, we can outperform the original 640 features (169 diagnosis categories and 471 medication types) to achieve an area under the receiver operator characteristic curve (AUC) of 0.720 (95% CI 0.715 to 0.725). Moreover, in

  15. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States. Results of exposures, 1984--1988

    SciTech Connect

    Reimann, K.J.

    1991-09-01

    Gravimetric changes in marble and limestone briquettes exposed to outdoor environment at five sites in the eastern United States have been monitored since 1984. An earlier report describes procedures and results obtained in 1984--1988. This report presents the results of the exposure period 1984--1988 and reviews and summarizes those of prior years. A linear relationship was found between cumulative gravimetric losses and exposure period or rain depth. These losses resulted in an average recession rate of 14 to 24 {mu}m/yr for marble and twice that for limestone. Variations in recession among the various exposure sites can be ascribed to differences in rain depth and hydrogen ion concentration. The annual recession rates obtained from gravimetry yielded rates that were for marble twice those obtained from runoff experiments, and more than three times those for limestone; this indicates that physical erosion plays an important role. Gravimetric monitoring of exposed briquettes is continuing in a planned 10-yr program.

  16. Engaging Families through Artful Play

    ERIC Educational Resources Information Center

    Brown, Robert

    2015-01-01

    This paper explores how aligned arts and play experiences can extend child and family engagement in a public outdoor space. The importance of outdoor play for children is strongly advocated and in response local governments provide playgrounds and recreational open spaces. To extend further the experiences afforded in such spaces some local…

  17. Sand and Water Table Play

    ERIC Educational Resources Information Center

    Wallace, Ann H.; White, Mary J.; Stone, Ryan

    2010-01-01

    The authors observed preschoolers engaged at the sand and water table to determine if math could be found within their play. Wanting to understand how children interact with provided materials and what kinds of math ideas they explore during these interactions, the authors offer practical examples of how such play can promote mathematical…

  18. Outdoor Play: Combating Sedentary Lifestyles

    ERIC Educational Resources Information Center

    Thigpen, Betsy

    2007-01-01

    Increasingly sedentary lifestyles are contributing to overweight and other health concerns as children spend less and less time outside engaged in active play. Outdoor play provides important opportunities to explore the natural world, interact with peers, engage in vigorous physical activity, and learn about our environment. However, outdoor…

  19. Quarry Quest. A Field Trip Guide to the Indiana Limestone District, Monroe and Lawrence Counties, Indiana.

    ERIC Educational Resources Information Center

    Shewmaker, Sherman N.

    This guide provides information for planning a field trip to the Indiana Limestone District. This district, located in Monroe and Lawrence Counties, Indiana, is responsible for material that has dominated the building-limestone market in the United States for nearly a century. A few of the many well-known buildings using Indiana limestone are the…

  20. Using Play to Teach Writing

    ERIC Educational Resources Information Center

    Batt, Tom

    2010-01-01

    This article explores the potential of play in the teaching of college composition. Drawing primarily on the theoretical framework of D. W. Winnicott, the author describes how he used ludic pedagogies to provide first-year writing students a "potential space" in which to explore a range of course elements including composing conventions,…

  1. Types of permeability development in limestone aquifers in Britain

    NASA Astrophysics Data System (ADS)

    Worthington, S. R. H.

    2009-04-01

    Advances over the last forty years have resulted in a clear understanding of how dissolution processes in limestone rocks enhance aquifer permeability. Laboratory experiments on dissolution rates of calcite and dolomite have established that there is a precipitous drop in dissolution rates as chemical equilibrium is approached. These results have been incorporated into numerical models, simulating the effects of dissolution over time and showing that it occurs along the entire length of pathways through limestone aquifers. The pathways become enlarged and integrated over time, forming self-organized networks of channels (or solutionally-enlarged fractures or fissures) that typically have apertures in the millimetre to centimetre range. The networks discharge at point-located springs. Numerical models that simulate dissolutional enlargement of fractures in limestone aquifers have given many insights into the conditions that favour different styles of permeability enhancement. Two end-member channel network types may be distinguished, one with many channels of similar size and one where a small number of large channels conduct most of the flow. In the latter case the larger channels may be metres in diameter (i.e. caves). Numerical modelling has shown that the former type are favoured where there is densely fractured rock, high hydraulic gradients, and recharge water close to chemical saturation (c/ceq close to 1). The latter type are favoured where there is sparsely fractured rock, low hydraulic gradients, and low values of c/ceq. These two contrasting types of aquifer have no distinguishing names in the literature. It seems reasonable to define a karst aquifer as an aquifer with self-organized, high-permeability channel networks formed by positive feedback between dissolution and flow. In this case both these aquifer types are karst aquifers. Perhaps it would be appropriate to call the former "microkarstic" aquifers and the latter "macrokarstic" aquifers. The range

  2. Moss cushions facilitate water and nutrient supply for plant species on bare limestone pavements.

    PubMed

    Sand-Jensen, Kaj; Hammer, Kathrine Jul

    2012-10-01

    Dense moss cushions of different size are distributed across the bare limestone pavements on Øland, SE Sweden. Increasing cushion size is predicted to physically protect and improve performance and colonization by vascular plants. Therefore, we tested water balance, phosphorus supply, and species richness, and evaluated duration of plant activity during desiccation as a function of ground area, for a large collection of moss cushions. We found that lower evaporation and higher water storage contributed equally to extending the desiccation period with increasing cushion size. Evaporation rates declined by the -0.36 power of cushion diameter, and were not significantly different from -0.50 for the square root function previously predicted for the increasing thickness of the boundary layer, with greater linear dimensions for smooth flat objects at low wind velocities. Size dependence vanished under stagnant conditions. One moss species was added to the species pool for every nine-fold increase in cushion area. Vascular plants were absent from the smallest cushions, whereas one or two species, on average, appeared in 375- and 8,500-cm(2) cushions with water available for 6 and 10 days during desiccation. Phosphorus concentrations increased stepwise and four-fold from detritus to surface mosses and to vascular plants, and all three pools increased with cushion size. We conclude that cushion mosses and cushion size play a critical role in this resource-limited limestone environment by offering an oasis of improved water and nutrient supply to colonization and growth of plants.

  3. Influence of Water Content on the Mechanical Behaviour of Limestone: Role of the Clay Minerals Content

    NASA Astrophysics Data System (ADS)

    Cherblanc, F.; Berthonneau, J.; Bromblet, P.; Huon, V.

    2016-06-01

    The mechanical characteristics of various sedimentary stones significantly depend on the water content, where 70 % loss of their mechanical strengths can be observed when saturated by water. Furthermore, the clay fraction has been shown to be a key factor of their hydro-mechanical behaviour since it governs for instance the hydric dilation. This work aims at investigating the correlations between the clay mineral content and the mechanical weakening experienced by limestones when interacting with water. The experimental characterization focuses on five different limestones that exhibit very different micro-structures. For each of them, we present the determination of clay mineral composition, the sorption isotherm curve and the dependences of tensile and compressive strengths on the water content. It emerges from these results that, first, the sorption behaviour is mainly governed by the amount of smectite layers which exhibit the larger specific area and, second, the rate of mechanical strength loss depends linearly on the sorption capacity. Indeed, the clay fraction plays the role of a retardation factor that delays the appearance of capillary bridges as well as the mechanical weakening of stones. However, no correlation was evidenced between the clay content and the amplitude of weakening. Since the mechanisms whereby the strength decreases with water content are not clearly established, these results would help to discriminate between various hypothesis proposed in the literature.

  4. Moss cushions facilitate water and nutrient supply for plant species on bare limestone pavements.

    PubMed

    Sand-Jensen, Kaj; Hammer, Kathrine Jul

    2012-10-01

    Dense moss cushions of different size are distributed across the bare limestone pavements on Øland, SE Sweden. Increasing cushion size is predicted to physically protect and improve performance and colonization by vascular plants. Therefore, we tested water balance, phosphorus supply, and species richness, and evaluated duration of plant activity during desiccation as a function of ground area, for a large collection of moss cushions. We found that lower evaporation and higher water storage contributed equally to extending the desiccation period with increasing cushion size. Evaporation rates declined by the -0.36 power of cushion diameter, and were not significantly different from -0.50 for the square root function previously predicted for the increasing thickness of the boundary layer, with greater linear dimensions for smooth flat objects at low wind velocities. Size dependence vanished under stagnant conditions. One moss species was added to the species pool for every nine-fold increase in cushion area. Vascular plants were absent from the smallest cushions, whereas one or two species, on average, appeared in 375- and 8,500-cm(2) cushions with water available for 6 and 10 days during desiccation. Phosphorus concentrations increased stepwise and four-fold from detritus to surface mosses and to vascular plants, and all three pools increased with cushion size. We conclude that cushion mosses and cushion size play a critical role in this resource-limited limestone environment by offering an oasis of improved water and nutrient supply to colonization and growth of plants. PMID:22481304

  5. Noise suppression using preconditioned least-squares prestack time migration: application to the Mississippian limestone

    NASA Astrophysics Data System (ADS)

    Guo, Shiguang; Zhang, Bo; Wang, Qing; Cabrales-Vargas, Alejandro; Marfurt, Kurt J.

    2016-08-01

    Conventional Kirchhoff migration often suffers from artifacts such as aliasing and acquisition footprint, which come from sub-optimal seismic acquisition. The footprint can mask faults and fractures, while aliased noise can focus into false coherent events which affect interpretation and contaminate amplitude variation with offset, amplitude variation with azimuth and elastic inversion. Preconditioned least-squares migration minimizes these artifacts. We implement least-squares migration by minimizing the difference between the original data and the modeled demigrated data using an iterative conjugate gradient scheme. Unpreconditioned least-squares migration better estimates the subsurface amplitude, but does not suppress aliasing. In this work, we precondition the results by applying a 3D prestack structure-oriented LUM (lower–upper–middle) filter to each common offset and common azimuth gather at each iteration. The preconditioning algorithm not only suppresses aliasing of both signal and noise, but also improves the convergence rate. We apply the new preconditioned least-squares migration to the Marmousi model and demonstrate how it can improve the seismic image compared with conventional migration, and then apply it to one survey acquired over a new resource play in the Mid-Continent, USA. The acquisition footprint from the targets is attenuated and the signal to noise ratio is enhanced. To demonstrate the impact on interpretation, we generate a suite of seismic attributes to image the Mississippian limestone, and show that the karst-enhanced fractures in the Mississippian limestone can be better illuminated.

  6. Noise suppression using preconditioned least-squares prestack time migration: application to the Mississippian limestone

    NASA Astrophysics Data System (ADS)

    Guo, Shiguang; Zhang, Bo; Wang, Qing; Cabrales-Vargas, Alejandro; Marfurt, Kurt J.

    2016-08-01

    Conventional Kirchhoff migration often suffers from artifacts such as aliasing and acquisition footprint, which come from sub-optimal seismic acquisition. The footprint can mask faults and fractures, while aliased noise can focus into false coherent events which affect interpretation and contaminate amplitude variation with offset, amplitude variation with azimuth and elastic inversion. Preconditioned least-squares migration minimizes these artifacts. We implement least-squares migration by minimizing the difference between the original data and the modeled demigrated data using an iterative conjugate gradient scheme. Unpreconditioned least-squares migration better estimates the subsurface amplitude, but does not suppress aliasing. In this work, we precondition the results by applying a 3D prestack structure-oriented LUM (lower-upper-middle) filter to each common offset and common azimuth gather at each iteration. The preconditioning algorithm not only suppresses aliasing of both signal and noise, but also improves the convergence rate. We apply the new preconditioned least-squares migration to the Marmousi model and demonstrate how it can improve the seismic image compared with conventional migration, and then apply it to one survey acquired over a new resource play in the Mid-Continent, USA. The acquisition footprint from the targets is attenuated and the signal to noise ratio is enhanced. To demonstrate the impact on interpretation, we generate a suite of seismic attributes to image the Mississippian limestone, and show that the karst-enhanced fractures in the Mississippian limestone can be better illuminated.

  7. Overview of Trenton exploration and development in New York state

    SciTech Connect

    Drazan, D.J.

    1987-09-01

    Exploration and development of the Middle Ordovician Trenton Limestone has occurred in New York state since the late 1800s. From the early days of exploration to the present, the Trenton has proven to be an elusive target for developers. However, renewed interest and current activity, coupled with improved drilling and completion techniques, may yet prove the Trenton Limestone in New York to be an important reservoir.

  8. Characterization of limestone reacted with acid-mine drainage in a pulsed limestone bed treatment system at the Friendship Hill National Historical Site, Pennsylvania, USA

    USGS Publications Warehouse

    Hammarstrom, J.M.; Sibrell, P.L.; Belkin, H.E.

    2003-01-01

    Armoring of limestone is a common cause of failure in limestone-based acid-mine drainage (AMD) treatment systems. Limestone is the least expensive material available for acid neutralization, but is not typically recommended for highly acidic, Fe-rich waters due to armoring with Fe(III) oxyhydroxide coatings. A new AMD treatment technology that uses CO2 in a pulsed limestone bed reactor minimizes armor formation and enhances limestone reaction with AMD. Limestone was characterized before and after treatment with constant flow and with the new pulsed limestone bed process using AMD from an inactive coal mine in Pennsylvania (pH = 2.9, Fe = 150 mg/l, acidity = 1000 mg/l CaCO3). In constant flow experiments, limestone is completely armored with reddish-colored ochre within 48 h of contact in a fluidized bed reactor. Effluent pH initially increased from the inflow pH of 2.9 to over 7, but then decreased to 6 during operation. Limestone removed from a pulsed bed pilot plant is a mixture of unarmored, rounded and etched limestone grains and partially armored limestone and refractory mineral grains (dolomite, pyrite). The ???30% of the residual grains in the pulsed flow reactor that are armored have thicker (50- to 100-??m), more aluminous coatings and lack the gypsum rind that develops in the constant flow experiment. Aluminium-rich zones developed in the interior parts of armor rims in both the constant flow and pulsed limestone bed experiments in response to pH changes at the solid/solution interface. ?? 2003 Elsevier Ltd. All rights reserved.

  9. Origin and Age of the Yemi Limestone Breccia, Korea

    NASA Astrophysics Data System (ADS)

    KOH, Hee Jae

    2015-04-01

    The Yemi Limestone Breccia (YLB), which has been argued for its age and depositional origin, occurs sporadically in the upper part of the Cambro-Ordovician Chosun Supergroup (CS) in Korean Peninsula. The YLB is characterized by a carbonate breccia with calcareous and carbonaceous shale matrix. Based on occurrence and composition of breccia and matrix, the YLB can be classified into Type-I and Type-II carbonate breccia. Type-I carbonate breccia comprises dark gray to light gray limestone and lime-mudstone breccia with calcareous matrix and is commonly constrained within the upper part of the CS as a lens-shaped zonal occurrence. The Type-I carbonate breccia results in syn-depositional solution-collapsed brecciation through karstification during intermittent subareal exposure of platform carbonate in Middle Ordovician. Type-II carbonate breccia mainly occurs in the uppermost part of the CS showing an irregular-shaped distribution rather than sheet-like layering parallel to bedding. Type-II carbonate breccia consists of gray to dark gray limestone and lime-mudstone breccia and shale matrix. Matrix is typically purple to reddish and gray to dark gray shale with minor amount of sandstone, and partly carbonaceous indicating organic origin. Most of Type-II carbonate breccia is morphologically classified into chaotic breccia. Matrix and breccia display considerable difference of composition and deformational structures. Breccia preserves various penetrative ductile to brittle deformation structures such as cleavage superimposing bedding, minor fold structure, minor faults crosscutting both dolomite and calcite veins, and fracture zones filled in calcite. However, these deformational structures of breccia do not continuously extended into matrix. Especially Type-II carbonate breccia is well observed in limestone of the lower part of unconformity between CS and clastic rocks of the Jurassic Bansong Group (BS). Fractured and solution zones of brecciated limestone of the CS

  10. Thermo-Hydro-Mechanical-Chemical Coupled Modeling of Geothermal Doublet Systems in Limestones -revised

    NASA Astrophysics Data System (ADS)

    Rühaak, Wolfram; Heldmann, Claus-Dieter; Pei, Liang; Bartels, Jörn; Weinert, Sebastian; Sass, Ingo

    2016-04-01

    Limestone aquifers in Southern Germany have been used within the last decade very successfully for geothermal heating and - to a lesser extent - for power generation. As an example the region around Munich has been extensively explored. While the extent of usage of this reservoir is increasing there is also an increased interest in better understanding of the reservoir properties and its change in the course of operation. For instance, the observed production and injection pressures are partly hard to explain. They may be related to mechanical or chemical processes, or both. Based on extensive data of outcrop studies and drillings, a data-base for the relevant physical properties of the respective limestones has been complied. The data include thermal conductivity, density, specific heat capacity, permeability, as well as mechanical properties like thermal expansion coefficient and elasticity modules. By using the hydro-thermo-chemical simulator FEFLOW together with an extension for thermo- and hydro-mechanical coupling the relevant processes are studied and compared with observed data. At the EGU Meeting in 2015 results of an initial study have been presented. This time results based on a completely new model setup and also using newly developed code will be presented. As a conclusion main challenges while modeling THMC fracture flow by using a multi-continua approach will be discussed.

  11. Performance of portland limestone cements: Cements designed to be more sustainable that include up to 15% limestone addition

    NASA Astrophysics Data System (ADS)

    Barrett, Timothy J.

    In 2009, ASTM and AASHTO permitted the use of up to 5% interground limestone in ordinary portland cement (OPC) as a part of a change to ASTM C150/AASHTO M85. When this work was initiated a new proposal was being discussed that would enable up to 15% interground limestone cement to be considered in ASTM C595/AASHTO M234. This work served to provide rapid feedback to the state department of transportation and concrete industry for use in discussions regarding these specifications. Since the time this work was initiated, ASTM C595/AASHTO M234 was passed (2012c) and PLCs are now able to be specified, however they are still not widely used. The proposal for increasing the volume of limestone that would be permitted to be interground in cement is designed to enable more sustainable construction, which may significantly reduce the CO2 that is embodied in the built infrastructure while also extending the life of cement quarries. Research regarding the performance of cements with interground limestone has been conducted by the cement industry since these cements became widely used in Europe over three decades ago, however this work focuses on North American Portland Limestone Cements (PLCs) which are specifically designed to achieve similar performance as the OPCs they replace.This thesis presents a two-phase study in which the potential for application of cements containing limestone was assessed. The first phase of this study utilized a fundamental approach to determine whether cement with up to 15% of interground or blended limestone can be used as a direct substitute to ordinary portland cement. The second phase of the study assessed the concern of early age shrinkage and cracking potential when using PLCs, as these cements are typically ground finer than their OPC counterparts. For the first phase of the study, three commercially produced PLCs were obtained and compared to three commercially produced OPCs made from the same clinker. An additional cement was tested

  12. Performance of portland limestone cements: Cements designed to be more sustainable that include up to 15% limestone addition

    NASA Astrophysics Data System (ADS)

    Barrett, Timothy J.

    In 2009, ASTM and AASHTO permitted the use of up to 5% interground limestone in ordinary portland cement (OPC) as a part of a change to ASTM C150/AASHTO M85. When this work was initiated a new proposal was being discussed that would enable up to 15% interground limestone cement to be considered in ASTM C595/AASHTO M234. This work served to provide rapid feedback to the state department of transportation and concrete industry for use in discussions regarding these specifications. Since the time this work was initiated, ASTM C595/AASHTO M234 was passed (2012c) and PLCs are now able to be specified, however they are still not widely used. The proposal for increasing the volume of limestone that would be permitted to be interground in cement is designed to enable more sustainable construction, which may significantly reduce the CO2 that is embodied in the built infrastructure while also extending the life of cement quarries. Research regarding the performance of cements with interground limestone has been conducted by the cement industry since these cements became widely used in Europe over three decades ago, however this work focuses on North American Portland Limestone Cements (PLCs) which are specifically designed to achieve similar performance as the OPCs they replace.This thesis presents a two-phase study in which the potential for application of cements containing limestone was assessed. The first phase of this study utilized a fundamental approach to determine whether cement with up to 15% of interground or blended limestone can be used as a direct substitute to ordinary portland cement. The second phase of the study assessed the concern of early age shrinkage and cracking potential when using PLCs, as these cements are typically ground finer than their OPC counterparts. For the first phase of the study, three commercially produced PLCs were obtained and compared to three commercially produced OPCs made from the same clinker. An additional cement was tested

  13. The effects of additive on limestone capturing sulfur during coal combustion

    SciTech Connect

    Chang, L.; Zhu, S.; Xie, K.; Liu, J.

    1998-12-31

    During high sulfur coal combustion, the desulfurization capacity of calcium-based sorbents has been investigated. The roles of additives in limestone were obvious and the capturing sulfur capacity of limestone containing additives is superior to that of only limestone under given reaction condition. The interaction mechanism of additive, limestone and SO{sub 2} was determined by DTA-TG and EA technology. These measurements showed that the reactions of limestone desulfurization primarily occurred at the first section of coal combustion, the active component is calcium carbonate and the reaction mechanism is not alike for additives existing or not.

  14. EFFECT OF AN ACID RAIN ENVIRONMENT ON LIMESTONE SURFACES.

    USGS Publications Warehouse

    Mossotti, Victor G.; Lindsay, James R.; Hochella, Michael F.

    1987-01-01

    Salem limestone samples were exposed to weathering for 1 y in several urban and one rural environments. Samples exposed in the rural location were chemically indistinguishable from the freshly quarried limestone, whereas all samples collected from urban exposure sites developed gypsum stains on the ground-facing surfaces where the stones were not washed by precipitation. The gas-solid reaction of SO//2 with calcite was selected for detailed consideration. It appears from the model that under arid conditions, the quantity of stain deposited on an unwashed surface is independent of atmospheric SO//2 concentration once the surface has been saturated with gypsum. Under wet conditions, surface sulfation and weight loss are probably dominated by mechanisms involving wet stone. However, if the rain events are frequent and delimited by periods of dryness, the quantity of gypsum produced by a gas-solid reaction mechanism should correlate with both the frequency of rain events and the atmospheric SO//2 level.

  15. Cement substitution by a combination of metakaolin and limestone

    SciTech Connect

    Antoni, M.; Rossen, J.; Martirena, F.; Scrivener, K.

    2012-12-15

    This study investigates the coupled substitution of metakaolin and limestone in Portland cement (PC). The mechanical properties were studied in mortars and the microstructural development in pastes by X-ray diffraction, thermogravimetry analysis, mercury intrusion porosimetry and isothermal calorimetry. We show that 45% of substitution by 30% of metakaolin and 15% of limestone gives better mechanical properties at 7 and 28 days than the 100% PC reference. Our results show that calcium carbonate reacts with alumina from the metakaolin, forming supplementary AFm phases and stabilizing ettringite. Using simple mass balance calculations derived from thermogravimetry results, we also present the thermodynamic simulation for the system, which agrees fairly well with the experimental observations. It is shown that gypsum addition should be carefully balanced when using calcined clays because it considerably influences the early age strength by controlling the very rapid reaction of aluminates.

  16. Preservation of York Minster historic limestone by hydrophobic surface coatings.

    PubMed

    Walker, Rachel A; Wilson, Karen; Lee, Adam F; Woodford, Julia; Grassian, Vicki H; Baltrusaitis, Jonas; Rubasinghege, Gayan; Cibin, Giannantonio; Dent, Andrew

    2012-01-01

    Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO(2) emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from 'breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO(2)/H(2)O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation.

  17. Preservation of York Minster historic limestone by hydrophobic surface coatings.

    PubMed

    Walker, Rachel A; Wilson, Karen; Lee, Adam F; Woodford, Julia; Grassian, Vicki H; Baltrusaitis, Jonas; Rubasinghege, Gayan; Cibin, Giannantonio; Dent, Andrew

    2012-01-01

    Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO(2) emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from 'breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO(2)/H(2)O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation. PMID:23198088

  18. Remanent magnetization of a Pliensbachian limestone sequence at Bakonycsernye (Hungary)

    NASA Astrophysics Data System (ADS)

    Márton, E.; Márton, P.; Heller, F.

    1980-06-01

    Remanent coercivity spectra derived from IRM acquisition curves and thermal demagnetization of the IRM indicate that magnetite, haematite and minor amounts of goethite determine the magnetic properties of the Pliensbachian limestones at Bakonycsernye. These limestones have been sampled at approximately 7-cm intervals along a 10-m stratigraphic section which covers the whole Pliensbachian stage (Lower Jurassic) without any recognizable break in sedimentation. The primary natural remanent magnetization (NRM) is carried by detrital particles of magnetite and haematite, but it is seriously overprinted by a normal magnetization which originates from secondary haematite with a wide range of blocking temperatures. This haematite is believed to have formed diagenetically during one of the Mesozoic periods of normal polarity. However, the reversal pattern obtained after NRM thermal demagnetization at temperatures ≥450°C is thought to be characteristic of the Pliensbachian stage.

  19. Risk analysis of prospects vs. plays: The play`s the thing!

    SciTech Connect

    Rose, P.R.

    1996-09-01

    The most difficult and crucial decision in petroleum exploration is not which prospect to drill, but rather, which new play to enter. Such a decision, whether ultimately profitable or not, commits the Organization to years of involvement, expenditures of $millions, and hundreds of man-years of effort. Even though uncertainties and risks are high, organizations commonly make the new-play decision in a disjointed, non-analytic, even superficial way. The economic consequences of a bad play choice can be disastrous. Using established principles of prospect risk analysis, modern petroleum exploration organizations routinely assign economic value to individual prospects, but they actually operate via exploration programs in plays and trends. Accordingly, the prospect is the economic unit of exploration, whereas the play is the operational unit. Plays can be successfully analyzed as full-cycle economic risk ventures, however, using many principles of prospect risk analysis. Economic measures such as Expected Present Value, DCFROR, etc. apply equally to plays or prospects. The predicted field-size distribution of the play is analogous to the forecast prospect reserves distribution. Economic truncation applies to both. Variance of play reserves is usually much greater than for prospect reserves. Geologic chance factors such as P{sub reservoir}, P{sub generation}, etc., must be distinguished as independent or shared among prospects in the play, so they should be defined so as to apply as well to the play as to its constituent prospects. They are analogous to multiple objectives on a prospect, and are handled different in reforming the risk analysis.

  20. Full-scale results for TAM limestone injection

    SciTech Connect

    Baer, S.

    1996-12-31

    Information is outlined on the use of thermally active marble (TAM) sorbents in boilers. Data are presented on: the comparison of TAM to limestone; NOVACON process development history; CFB test history; CFB pilot scale test; full-scale CFB trial; August, 1996 CFB demonstration; Foster Wheeler Mount Carmel sorbent feed rate comparison and Ca:S comparison; unburned carbon is ash; and advantages and savings in CFB boilers.

  1. National conference on agricultural limestone. Bulletin Y-166

    SciTech Connect

    Not Available

    1981-09-01

    Twenty-three papers were presented on various facets of the agricultural limestone (aglime) industry - from the quarry to the farmers. They are organized under the following section headings: introduction and overview; status of current use and need; agronomic situation; a total approach to marketing aglime, producing aglime; and a look to the future. Panel discussions were held on the topics, responding to the seasonal nature of aglime use and regional reviews of the status and opportunities for aglime use. (JGB)

  2. Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands

    USGS Publications Warehouse

    Hein, J.R.; Gray, S.C.; Richmond, B.M.; White, L.D.

    1992-01-01

    The primary reef framework is considered to have been deposited during several highstands of sea level. Following partial to local recrystallization of the limestone, a signle episode of dolomitization occurred. Both tidal and thermal pumping drove large quantities of seawater through the porous rocks and perhaps maintained a wide mixing zone. However, the isotopic, geochemical and petrographic data do not clearly indicate the extent of seawater mixing. -from Authors

  3. Time-Dependent Rock Failure in a Heterogeneous Limestone

    NASA Astrophysics Data System (ADS)

    Roth, K.; Kemeny, J.

    2015-12-01

    Time-dependent rock failure is an important aspect in the analysis of long-term rock stability for slopes, dam and bridge foundations, and underground storage facilities. An on-going project at the University of Arizona is using Kartchner Caverns in Benson, Arizona as a natural analog to study such failure by reconstructing the process of natural cave breakdown with subcritical crack growth modeling. Breakdown is thought to occur along joints through the time-dependent failure of rock bridges: sections of intact rock separating discontinuities in a rock mass. The Escabrosa limestone composing the caverns ranges from a more homogenous, even-grained texture to a more heterogeneous texture consisting of coarse-grained veins and solution cavities set in a fine-grained matrix. To determine if the veined regions are more susceptible to fracturing and act as the nuclei of rock bridge failure, fracture toughness tests were conducted for both textures. The subcritical crack growth parameters were calculated using the constant stress-rate method. Results indicate that the more heterogeneous limestone has a higher fracture strength, fracture toughness, and subcritical crack growth index n than the more homogeneous limestone. This is in agreement with previous studies which found that a more complex and heterogeneous microstructure produces a larger microcrack process zone, leading to higher fracture energies and lower susceptibility to subcritical crack growth. Thus, despite their solution cavities, the calcite veins do not localize failure or act as planes of weakness; instead, rock bridges fail through the more homogeneous limestone matrix.

  4. Modified dry limestone process for control of sulfur dioxide emissions

    DOEpatents

    Shale, Correll C.; Cross, William G.

    1976-08-24

    A method and apparatus for removing sulfur oxides from flue gas comprise cooling and conditioning the hot flue gas to increase the degree of water vapor saturation prior to passage through a bed of substantially dry carbonate chips or lumps, e.g., crushed limestone. The reaction products form as a thick layer of sulfites and sulfates on the surface of the chips which is easily removed by agitation to restore the reactive surface of the chips.

  5. Recovery and recycling of limestone in LEC flue gas desulfurization. Final report, third year

    SciTech Connect

    Gardner, N.C.; Boo, J.Y.

    1993-12-20

    A potentially attractive flue gas desulfurization method called Limestone Emission Control (LEC) is currently being investigated by Prudich at Ohio University. In this process, beds of 1/8 inch limestone gravel particles absorb sulfur dioxide from flue gas. This forms sulfite and sulfate salts which coat limestone, blinding the surface and limiting utilization to 20%. Favorable economics can be generating when the unreacted portion of the limestone is recovered by mechanical grinding. This project is a wet method for grinding and recovering the spent limestone from the LEC process, utilizing an impeller fluidizer, a new type of slurry processor. It consists of a cylindrical vessel with an impeller at one end. The impeller generates sufficient pressure head to serve as a slurry pump. It combines the operation of wet grinding, washing, and transporting the spent and recovered limestone as an aqueous slurry. The objectives of the first two years were to operate fluidizer in a batch mode to carry grinding experiments, and to determine the removal of the sulfur coatings from the limestone when operating the fluidizer in a continuous mode. The main thrusts of the third year were to complete the grinding data and coordinate the data with reactivity determinations of the recovered limestone. Direct measurement of power requirements, operation of single impeller fluidizer, grinding of surface deposits and other methods of removing surface deposits have also been investigated along with sorption characteristics of recovered limestone, microscopic examination of the limestone surface, and limestone attrition.

  6. Effects of limestone on the dissolution of phosphate from sediments under anaerobic condition.

    PubMed

    Kim, H S; Park, J

    2008-04-01

    This paper describes a study on the role of limestone on the dissolution of phosphates when phosphate-containing sediments are put under anaerobic conditions. Anaerobic decomposition of organic substances produces both organic acids and carbonic acids which in turn could accelerate the dissolution of the phosphates. If limestone coexisted, both phosphate and limestone would compete as receptors of hydrogen ions so as to affect the dissolution of phosphate. A small quantity of calcium hydroxyapatite, alone or mixed with limestone powder, was put in contact with an aqueous solution of acetic acid or carbonic acid and the variations in phosphate concentration were determined over time. The results showed that the phosphate concentration was remarkably low in the case of limestone presence, in comparison with the case of limestone absence. This signifies that the coexistence of limestone suppresses the dissolution of phosphate by organic acid and/or carbonic acid. Separate experiments conducted by developing an anaerobic condition, after mixing lake sediments with dried leaves and limestone, allowed us to observe that the existence of limestone suppressed the dissolution of phosphate. It seems that the limestone acts as a material sacrificing to the leaching of hydrogen ions from the acids produced under anaerobic conditions. These results show that the application of limestone might be a useful measure to prevent deterioration of water quality through eutrophication, by breaking the internal loading of phosphates in eutrophic water bodies. PMID:18619142

  7. Development of gypsum alteration on marble and limestone

    USGS Publications Warehouse

    McGee, E.S.

    1996-01-01

    Blackened alteration crusts of gypsum plus particulates that form on sheltered areas on marble and limestone buildings pose a challenge for rehabilitation and cleaning. Fresh marble and limestone samples exposed at monitored exposure sites present conditions of simple geometry and well-documented exposures but have short exposure histories (one to five years). The gypsum alteration crusts that develop on these samples provide insight into the early stages and rate of alteration crust formation. Alteration crusts from buildings give a longer, but less well known exposure history and present much more complex surfaces for gypsum accumulation. Integrated observations and measurements of alteration crusts from exposure samples and from buildings identify four factors that are important in the formation and development of alteration crusts on marble and limestone: (1) pollution levels, (2) exposure to rain or washing, (3) geometry of exposure of the stone surface, and (4) permeability of the stone. The combination of these factors contributes to both the distribution and the physical characteristics of the gypsum crusts which may affect cleaning decisions.

  8. Stratigraphy of the Upper Pleistocene Miami Limestone of Florida

    SciTech Connect

    Johnson, R.A.

    1993-03-01

    The upper Pleistocene Miami Limestone is probably the most stratigraphically-complex formation in the Cenozoic of Florida. The Miami overlies and vertically/laterally grades into the upper Pleistocene Ft. Thompson Formation to the west in southeast Palm Beach County (west of I-95); to the west in Broward County (west of the Turnpike); and to the north in south Broward County (along U.S. 27). The Miami overlies and very locally vertically grades into the Ft. Thompson in all of Dade County. The Miami overlies and vertically/laterally grades into the upper Pleistocene Anastasia Formation to the north and east in southeast Palm Beach County (east of I-95), and to the northeast in east Broward County (east of the Turnpike). The Miami laterally grades into the upper Pleistocene Key Largo Limestone to the southeast in extreme southeast Dade County, and overlies and locally vertically grades into the Key Largo in the Lower Keys, south Monroe County. The Miami unconformably overlies the Pliocene Tamiami Formation and pinches out to the west in northeast mainland Monroe and southeast Collier Counties, and also pinches out to the north in east-central Palm Beach County. In all areas, the Miami Limestone is either overlain unconformably by very discontinuous undifferentiated surficial sediments or forms land surface.

  9. Road dust resuspension in the vicinity of limestone quarries in Jordan.

    PubMed

    Abu-Allaban, Mahmoud; Hamasha, Safeia; Gertler, Alan

    2006-10-01

    Many areas in Jordan suffer from elevated levels of coarse particulate matter (PM10). One potentially significant source of the observed PM is the resuspension of road dust in the vicinity of limestone quarries. To obtain data to assess the impact from this source, PM10 road dust resuspension factors near Abusiiah, a town to the north east of Amman surrounded by many quarries and brick factories, were measured. Measurements included PM10 mass, particle size distributions, wind speed, and wind direction. The results showed that PM10 concentrations could be as high as 600 microg/m3, and most of the airborne PM is in the coarse fraction. Loading trucks play a major role in resuspending road dust, with an observed PM10 emission rate of >6000 mg/km.

  10. Minor non-carbonate authigenic components as indicators of late-stage diagenetic processes in the Smackover limestones

    SciTech Connect

    Denham, M.E. Jr.

    1992-01-01

    Variations in mineralogy and composition of late authigenic sulfur-bearing minerals in upper Smackover limestones recorded diagenetic events associated with hydrocarbon migration. This suite of minerals occurs in samples taken from 18 subsurface cores of the upper Smackover from northern Louisiana and southern Arkansas. Spatial variations in cadmium concentration of sphalerite, Ba concentration of celestite, and the [sigma][sup 34]S values of galena and sphalerite suggest that fluids associated with hydrocarbons in the lower Smackover migrated into the upper Smackover along faults at the Louisiana-Arkansas border. A second generation of sulfide mineralization and a [sigma][sup 34]S = +10.8[per thousand] CDT of a wurtzite-sphalerite mixture suggests that thermochemical sulfate reduction occurred after hydrocarbon migration resulting in the formation of the [open quotes]sour gas belt.[close quotes] Uranium concentration, as revealed by fission track imaging and instrumental neutron activation analyses, varies on a microscopic and regional scale in the upper Smackover limestones. Uranium is locally concentrated in stylolites and fine grained opaque material. Comparison of uranium and thorium concentrations in stylolites suggests these elements are insoluble residue of the pressure solution process. Regionally, uranium concentration varies with clay content of the host limestone indicating that sorption plays a major role in the geochemical behavior of uranium in the subsurface. Comparison of U/Th ratios of upper Smackover limestones to those of black shales from the Gray Sands tentatively suggests that uranium was redistributed from hydrocarbon source rocks to reservoir rocks. However, better understanding of the association of uranium with organic-rich rocks and the role of sorption are required before uranium can be used reliably as a pore fluid tracer.

  11. Thermo-poroelastic response of an argillaceous limestone

    NASA Astrophysics Data System (ADS)

    Selvadurai, Patrick; Najari, Meysam

    2016-04-01

    Argillaceous limestones are now being considered by many countries that intend to develop deep geologic storage facilities for siting both high-level and intermediate- to low-level nuclear fuel wastes. In deep geologic settings for high level nuclear wastes, the heating due to radioactive decay is transmitted through an engineered barrier, which consists of the waste container and an engineered geologic barrier, which consists of an encapsulating compacted bentonite. The heat transfer process therefore leads to heating of the rock mass where the temperature of the rock is substantially lower than the surface temperature of the waste container. This permits the use of mathematical theories of poroelastic media where phase transformations, involving conversion of water to a vapour form are absent. While the thermo-poroelastic responses of geologic media such as granite and porous tuff have been investigated in the literature, the investigation of thermo-poroelastic responses of argillaceous limestones is relatively new. Argillaceous limestones are considered to be suitable candidates for siting deep geologic repositories owing to the ability to accommodate stress states with generation of severe defects that can influence their transmissivity characteristics. Also the clay fraction in such rocks can contribute to long term healing type phenomena, which is a considerable advantage. This research presents the results of a laboratory investigation and computational modelling of the same that examines the applicability of the theory of thermo-poroelasticity, which extend Biot's classical theory of poroelasticity to include uncoupled heat conduction. The experimental configuration involves the boundary heating of a cylinder of the Cobourg Limestone from southern Ontario, Canada. The cylinder measuring 150 mm in diameter and 278 mm in length contains an axisymmetric fluid-filled cylindrical cavity measuring 26 mm in diameter and 139 mm in length. Thermo-poroelastic effects

  12. Structural characterization of a karstified limestone formation using GPR

    NASA Astrophysics Data System (ADS)

    Rousset, D.; Sénéchal, G.; Gaffet, S.

    2009-12-01

    The Laboratoire Souterrain à Bas Bruit (LSBB) at Rustrel - Pays d'Apt, France, is an Inter-disciplinary Underground Science and Technology Laboratory buried in a karstified limestone formation. A multidisciplinary program focused on water circulation monitoring is presently performed inside the tunnels. This program comprises the investigation of faults, fractures, karstification and stratigraphy ofthe limestone massif using GPR. We present the main results obtained from these data. The tunnel has been dug in lower cretaceous limestone which is characterized by a low clay content, high electrical resistivity which results in generally very low attenuation of electro-magnetic waves. 90% of the tunnels floor are made of concrete whereas other are made of bare limestone. This experimental site offers a unique opportunity of perfoming measurements within an unweathered limestone massif. The whole 3km long tunnel has been investigated using single offset shielded 250 MHz antennas in May 2009. Processing includes : DC and very low frequency removal, amplitude compensation preserving lateral variations, migration and time to depth conversion. When necessary predictive deconvolution has been applied to remove ringing effects. These data sets are characterized by good signal to noise ratio and a signal penetration down to 18 meters. These data allow us to accurately map the stratigraphy of the surrounding rocks across the concrete walls of the tunnel. Some 20 m deep vertical wells have been drilled inside the tunnel through observed reflectors. This is a strong validation of the GPR images. The estimated resolution is centimetric to decimetric and matches the required geologic accuracy. The GPR data set allows to extend previous geological results in depth, particularly in the concrete coated parts of the tunnel where conventional geological surveying is impossible. Thanks to the processing which preserves lateral amplitude variations, GPR sections exhibit prominent

  13. Calcium looping spent sorbent as a limestone replacement in the manufacture of portland and calcium sulfoaluminate cements.

    PubMed

    Telesca, Antonio; Marroccoli, Milena; Tomasulo, Michele; Valenti, Gian Lorenzo; Dieter, Heiko; Montagnaro, Fabio

    2015-06-01

    The calcium looping (CaL) spent sorbent (i) can be a suitable limestone replacement in the production of both ordinary Portland cement (OPC) and calcium sulfoaluminate (CSA) cement, and (ii) promotes environmental benefits in terms of reduced CO2 emission, increased energy saving and larger utilization of industrial byproducts. A sample of CaL spent sorbent, purged from a 200 kWth pilot facility, was tested as a raw material for the synthesis of two series of OPC and CSA clinkers, obtained from mixes heated in a laboratory electric oven within temperature ranges 1350°-1500 °C and 1200°-1350 °C, respectively. As OPC clinker-generating mixtures, six clay-containing binary blends were investigated, three with limestone (reference mixes) and three with the CaL spent sorbent. All of them showed similar burnability indexes. Moreover, three CSA clinker-generating blends (termed RM, MA and MB) were explored. They included, in the order: (I) limestone, bauxite and gypsum (reference mix); (II) CaL spent sorbent, bauxite and gypsum; (III) CaL spent sorbent plus anodization mud and a mixture of fluidized bed combustion (FBC) fly and bottom ashes. The maximum conversion toward 4CaO·3Al2O3·SO3, the chief CSA clinker component, was the largest for MB and almost the same for RM and MA. PMID:25915150

  14. Niger Delta play types, Nigeria

    SciTech Connect

    Akinpelu, A.O.

    1995-08-01

    Exploration databases can be more valuable when sorted by play type. Play specific databases provide a system to organize E & P data used in evaluating the range of values of parameters for reserve estimation and risk assessment. It is important both in focusing the knowledge base and in orienting research effort. A play in this context is any unique combination of trap, reservoir and source properties with the right dynamics of migration and preservation that results in hydrocarbon accumulation. This definitions helps us to discriminate the subtle differences found with these accumulation settings. About 20 play types were identified around the Niger Delta oil province in Nigeria. These are grouped into three parts: (1) The proven plays-constituting the bulk of exploration prospects in Nigeria today. (2) The unproven or semi-proven plays usually with some successes recorded in a few tries but where knowledge is still inadequate. (3) The unproven or analogous play concept. These are untested but geologically sound ideas which may or may not have been tried elsewhere. With classification and sub grouping of these play types into specific databases, intrinsic attributes and uniqueness of each of them with respect to the four major risk elements and the eight parameters for reserve estimation can be better understood.

  15. Major Oil Plays in Utah and Vicinity

    SciTech Connect

    Thomas C. Chidsey; Craig D. Morgan; Kevin McClure; Douglas A. Sprinkel; Roger L. Bon; Hellmut H. Doelling

    2003-12-31

    Utah oil fields have produced over 1.2 billion barrels (191 million m{sup 3}). However, the 13.7 million barrels (2.2 million m{sup 3}) of production in 2002 was the lowest level in over 40 years and continued the steady decline that began in the mid-1980s. The Utah Geological Survey believes this trend can be reversed by providing play portfolios for the major oil-producing provinces (Paradox Basin, Uinta Basin, and thrust belt) in Utah and adjacent areas in Colorado and Wyoming. Oil plays are geographic areas with petroleum potential caused by favorable combinations of source rock, migration paths, reservoir rock characteristics, and other factors. The play portfolios will include: descriptions and maps of the major oil plays by reservoir; production and reservoir data; case-study field evaluations; locations of major oil pipelines; identification and discussion of land-use constraints; descriptions of reservoir outcrop analogs; and summaries of the state-of-the-art drilling, completion, and secondary/tertiary techniques for each play. This report covers research activities for the sixth quarter of the project (October 1 through December 31, 2003). This work included describing outcrop analogs for the Jurassic Twin Creek Limestone and Mississippian Leadville Limestone, major oil producers in the thrust belt and Paradox Basin, respectively, and analyzing best practices used in the southern Green River Formation play of the Uinta Basin. Production-scale outcrop analogs provide an excellent view of reservoir petrophysics, facies characteristics, and boundaries contributing to the overall heterogeneity of reservoir rocks. They can be used as a ''template'' for evaluation of data from conventional core, geophysical and petrophysical logs, and seismic surveys. In the Utah/Wyoming thrust belt province, the Jurassic Twin Creek Limestone produces from subsidiary closures along major ramp anticlines where the low-porosity limestone beds are extensively fractured and sealed

  16. Play Therapy: A Review

    ERIC Educational Resources Information Center

    Porter, Maggie L.; Hernandez-Reif, Maria; Jessee, Peggy

    2009-01-01

    This article discusses the current issues in play therapy and its implications for play therapists. A brief history of play therapy is provided along with the current play therapy approaches and techniques. This article also touches on current issues or problems that play therapists may face, such as interpreting children's play, implementing…

  17. Inelastic compaction of a quartz-rich limestone (Invited)

    NASA Astrophysics Data System (ADS)

    Baud, P.; Schubnel, A.; rolland, A.; Heap, M. J.

    2013-12-01

    The analysis of deformation and failure in many sedimentary settings hinges upon a fundamental understanding of inelastic behavior and failure mode of porous carbonate rocks. Previous studies on porous carbonate focused primarily on relatively pure limestone (composed in majority of calcite). Inelastic compaction in these carbonates was reported to be associated to cataclastic pore collapse and in most cases homogeneous cataclastic flow. Recent experimental results however revealed the development of compaction localization in the more porous end-members. The analysis of strain localization and complex failure modes in limestone has proved to be significantly more challenging than in sandstone because acoustic emissions (AE) cannot usually be used to guide systematic microstructural analysis. Recent studies have therefore relied on X-ray Computed Tomography, a technique that can to date only be used in situ in relatively limited systems. In this study we investigated the development of inelastic damage in a quartz-rich limestone with two main objectives: (1) quantify the impact of a secondary mineral such as quartz on the strength and strain localization in porous carbonate, (2) try to follow the development of inelastic damage using AE in such a quartz-rich rock. Saint-Maximin limestone of 37% porosity and composed of 80% calcite and 20% quartz was selected for this study. Two series of conventional triaxial experiments were performed in parallel at room temperature, constant strain rate in both nominally dry and wet conditions at confining pressures between 3 and 50 MPa. Wet experiments were carried out with water in drained conditions at 10 MPa of pore pressure. The first series of experiments were performed at IPG Strasbourg on relatively small samples. The failure modes and spatial distribution of damage were studied systematically in these samples. The second series of experiments were performed on larger samples at ENS Paris. Acoustic emission activity was

  18. Effect of an acid rain environment on limestone surfaces

    SciTech Connect

    Mossotti, V.G.; Lindsay, J.R.; Hochella, M.F. Jr.

    1987-11-01

    As part of a study to assess mineralogical alterations in building stone caused by acid rain, Salem limestone samples were exposed for one year in several urban and one rural environments. Samples exposed in the rural location were chemically indistinguishable from the freshly quarried limestone (control material). All samples collected from urban exposure sites developed gypsum stains on the grounding surfaces, where the stones were unwashed by precipitation. However, the bulk chemistry of the urban samples (not including the stain) was virtually identical to that of the control stone. Sulfur (in the form of sulfate) was disseminated over the calcite grain surfaces to a depth less than 10 nanometer in the freshly quarried limestone; an identical sulfate layer was found on the calcite grains after the 1-y exposure period. Mass balance calculations and sulfur isotope patterns indicate that the gypsum stain on the protected surfaces consists of adventitious sulfur. A model, involving the attack of SO/sub 2/ on dry calcite, was used to define the conditions for stain formation on dry, protected surfaces. This suggests that under arid conditions, once the surface has been saturated with gypsum, the quantity of stain deposited on an unwashed surface is independent of atmospheric SO/sub 2/ concentration. On rain-washed surfaces experiencing gas-solid attack during intermittent dry periods, the quantity of gypsum produced by a gas-solid reaction mechanism should strongly correlate with both the frequency of rain events and the atmospheric SO/sub 2/ level, provided that the rain events are frequent and clearly delimited by periods of dryness.

  19. Water transport in limestone by X-ray CAT scanning

    USGS Publications Warehouse

    Mossoti, Victor G.; Castanier, Louis M.

    1989-01-01

    The transport of water through the interior of Salem limestone test briquettes can be dynamically monitored by computer aided tomography (commonly called CAT scanning in medical diagnostics). Most significantly, unless evaporation from a particular face of the briquette is accelerated by forced air flow (wind simulation), the distribution of water in the interior of the briquette remains more or less uniform throughout the complete drying cycle. Moreover, simulated solar illumination of the test briquette does not result in the production of significant water gradients in the briquette under steady-state drying conditions.

  20. Sodium-limestone double alkali flue gas desulfurization method

    SciTech Connect

    Wang, K.H.; Biolchini, R.J.; Legatski, L.K.

    1983-10-18

    A flue gas desulfurization method is disclosed for efficiently removing sulfur oxides from a gas stream with an aqueous sodium sulfite- and sodium bisulfite-containing absorption solution, in which absorber effluent solution at a pH of 5.8 to 6.6 and having an active sodium concentration of from 0.5 M to 0.9 M is regenerated with sufficient ground limestone to yield a treated solution with a higher pH of from 6.3 to 7.0 and whose bisulfite concentration is reduced by from 35 to 70%

  1. Penetration into limestone targets with ogive-nose steel projectiles

    SciTech Connect

    Frew, D.J.; Green, M.L.; Forrestal, M.J.; Hanchak, S.J.

    1996-12-01

    We conducted depth of penetration experiments into limestone targets with 3.0 caliber-radius-head, 4340 Rc 45 steel projectiles. Powder guns launched two projectiles with length-to-diameter ratios of ten to striking velocities between 0.4 and 1.5 km/s. Projectiles had diameters and masses of 12.7 mm, 0. 117 kg and 25.4 mm, 0.610 kg. Based on data sets with these two projectile scales, we proposed an empirical penetration equation that described the target by its density and an empirical strength constant determined from penetration depth versus striking velocity data.

  2. Absorption spectra of crystalline limestones experimentally deformed or tectonised

    NASA Astrophysics Data System (ADS)

    Cervelle, B.; ChayéD'Albissin, M.; Gouet, G.; Visocekas, R.

    1982-11-01

    Diffuse-reflectance spectra have been measured for a series of samples of Carrara marble experimentally deformed under different cylindrical stress ( P = 0, 100, 250, 500, 980 bars). The creation of point defects that results has been shown up classically by irradiation with β rays (40 krads), thus producing a typical blue coloration linked with the formation of colour centres. The diffuse-reflectance spectra, measured on powders with a microscope-spectrometer in the visible range (400-800 nm), allow the determination of the absorption spectra by means of the Kubelka-Munk function. These absorption spectra have been measured for each of the deformed samples, as well as for different fractions of a very deformed specimen subsequently heated at temperatures between 100 and 500° C for a fixed time. In the same way, tectonised crystalline limestones, of various origins, were studied without any other treatment than the irradiation with β rays. From this study the following preliminary conclusions have been drawn: (1) The absorption spectrum of an undeformed but merely irradiated specimen of crystalline limestone is practically monotonous, but in the deformed specimens a broad band of absorption appears, having a maximum at 620 nm with several shoulders, the chief of which is at 520 nm. (2) This absorption band shows the existence of colour centres, the density of which can be estimated relatively by means of the chromaticity coordinates x and y of the C.I.E. obtained from the diffuse-reflectance spectra (C.I.E. = Commission Internationale de l'Éclairage). (3) An overgrinding of calcite generates defects that have the same spectra as those produced during the experimental deformation. Consequently, in obtaining the powders of grain size 50-80 μm needed for the diffuse spectrometry, great care must be exercised. (4) For a given confining pressure, the defect density is proportional to the deformation rate. (5) One can calibrate the effect of the annealing of

  3. Elucidation of denitrification mechanism in karstic Ryukyu limestone aquifer

    NASA Astrophysics Data System (ADS)

    Hijikawa, K.

    2014-12-01

    Nitrate (NO3-) concentrations in public water supplies have risen above acceptable levels in many areas of the world including Japan, largely as a result of contamination by human and animal waste and overuse of fertilizers. A previous study has characterized nitrate concentrations in groundwater in this area is a higher than the upper value (44mgL-1) of environmental quality criteria on one hands. On the other hand, there exists points where the concentration of nitric acid is not detected, which suggests the possibility of denitrification. During early 2000, a new analytical procedure for nitrate isotopic measurement, termed the "denitrifier method", was established. With the development of the nitrate isotope tracer method, much research has been reported detailing sources of groundwater nitrate and denitrification mechanisms. This study presents a pilot case study (in the southern part of Okinawa Main Island, Japan, where Ryukyu limestone is extensively distributed) using the combined stable isotope ratios of major elements (C, N and S) as net recorders of the biogeochemical reactions with the aim of elucidation of denitrification mechanism in Ryukyu limestone aquifer. As a result, significant decreases in nitrate concentrations due to denitrification were observed in groundwater at some locations, which induced increases in isotope ratios up to 59.7‰ for δ15NNO3. These points of groundwater were located above the cutoff wall of the underground dam and near the fault. It is considered that the residence time of the groundwater is longer than the other points at these denitrification points, and that reduction condition tends to be formed in the groundwater. However, the rapid rise of the groundwater level due to rainfall is likely to occur in the Ryukyu limestone aquifer, where the ground water was found to have changed dynamically from the reduction condition to the oxidation condition which a denitrification (has not occured)does not occur. Moreover, the

  4. Bio-deposition of a calcium carbonate layer on degraded limestone by Bacillus species.

    PubMed

    Dick, Jan; De Windt, Wim; De Graef, Bernard; Saveyn, Hans; Van der Meeren, Paul; De Belie, Nele; Verstraete, Willy

    2006-08-01

    To obtain a restoring and protective calcite layer on degraded limestone, five different strains of the Bacillus sphaericus group and one strain of Bacillus lentus were tested for their ureolytic driven calcium carbonate precipitation. Although all the Bacillus strains were capable of depositing calcium carbonate, differences occurred in the amount of precipitated calcium carbonate on agar plate colonies. Seven parameters involved in the process were examined: calcite deposition on limestone cubes, pH increase, urea degrading capacity, extracellular polymeric substances (EPS)-production, biofilm formation, zeta-potential and deposition of dense crystal layers. The strain selection for optimal deposition of a dense CaCO(3) layer on limestone, was based on decrease in water absorption rate by treated limestone. Not all of the bacterial strains were effective in the restoration of deteriorated Euville limestone. The best calcite precipitating strains were characterised by high ureolytic efficiency, homogeneous calcite deposition on limestone cubes and a very negative zeta-potential. PMID:16491305

  5. Effect of water treatment chemicals on limestone/sulfur dioxide reaction in flue gas desulfurization systems

    SciTech Connect

    Dille, E.R.; Gaikwad, R.P.

    1994-12-31

    A simple laboratory test has been developed which simulates the reaction between limestone/water and sulfur dioxide in flue gas desulfurization systems. By adding various chemicals, in differing concentrations, to the limestone/water mixture, the quantitative impact on the sulfur dioxide/limestone reaction can be qualified and quantified. This paper will present the impact of several water treatment chemicals on the reaction of limestone and sulfur dioxide. An attempt has been made to predict the effect through mathematical correlations. All of the additive chemicals tend to decrease the rate of dissolution of limestone to various degrees. Some of the chemicals retard crystal growth thus adversely impacting solids separation in the thickener. The physical appearance of the crystal growth retarded limestone absorber slurry approaches a colloidal suspension.

  6. Bio-deposition of a calcium carbonate layer on degraded limestone by Bacillus species.

    PubMed

    Dick, Jan; De Windt, Wim; De Graef, Bernard; Saveyn, Hans; Van der Meeren, Paul; De Belie, Nele; Verstraete, Willy

    2006-08-01

    To obtain a restoring and protective calcite layer on degraded limestone, five different strains of the Bacillus sphaericus group and one strain of Bacillus lentus were tested for their ureolytic driven calcium carbonate precipitation. Although all the Bacillus strains were capable of depositing calcium carbonate, differences occurred in the amount of precipitated calcium carbonate on agar plate colonies. Seven parameters involved in the process were examined: calcite deposition on limestone cubes, pH increase, urea degrading capacity, extracellular polymeric substances (EPS)-production, biofilm formation, zeta-potential and deposition of dense crystal layers. The strain selection for optimal deposition of a dense CaCO(3) layer on limestone, was based on decrease in water absorption rate by treated limestone. Not all of the bacterial strains were effective in the restoration of deteriorated Euville limestone. The best calcite precipitating strains were characterised by high ureolytic efficiency, homogeneous calcite deposition on limestone cubes and a very negative zeta-potential.

  7. Playing in the Gutters: Enhancing Children's Cognitive and Social Play.

    ERIC Educational Resources Information Center

    Dinwiddie, Sue A.

    1993-01-01

    Adding plastic gutters to the nursery school's sand area began as a science curriculum enhancement and evolved into a whole curriculum that stimulated cognitive exploration, cooperative dramatic play, language enhancement, and general fun. The children manipulated the gutters and materials such as sand, water, buckets, and tennis balls in a…

  8. Symbolic play and language development.

    PubMed

    Orr, Edna; Geva, Ronny

    2015-02-01

    Symbolic play and language are known to be highly interrelated, but the developmental process involved in this relationship is not clear. Three hypothetical paths were postulated to explore how play and language drive each other: (1) direct paths, whereby initiation of basic forms in symbolic action or babbling, will be directly related to all later emerging language and motor outputs; (2) an indirect interactive path, whereby basic forms in symbolic action will be associated with more complex forms in symbolic play, as well as with babbling, and babbling mediates the relationship between symbolic play and speech; and (3) a dual path, whereby basic forms in symbolic play will be associated with basic forms of language, and complex forms of symbolic play will be associated with complex forms of language. We micro-coded 288 symbolic vignettes gathered during a yearlong prospective bi-weekly examination (N=14; from 6 to 18 months of age). Results showed that the age of initiation of single-object symbolic play correlates strongly with the age of initiation of later-emerging symbolic and vocal outputs; its frequency at initiation is correlated with frequency at initiation of babbling, later-emerging speech, and multi-object play in initiation. Results support the notion that a single-object play relates to the development of other symbolic forms via a direct relationship and an indirect relationship, rather than a dual-path hypothesis. PMID:25658200

  9. Characterization of the spatial distribution of porosity in the eogenetic karst Miami Limestone using ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Mount, G. J.; Comas, X.; Wright, W. J.; McClellan, M. D.

    2014-12-01

    Hydrogeologic characterization of karst limestone aquifers is difficult due to the variability in the spatial distribution of porosity and dissolution features. Typical methods for aquifer investigation, such as drilling and pump testing, are limited by the scale or spatial extent of the measurement. Hydrogeophysical techniques such as ground penetrating radar (GPR) can provide indirect measurements of aquifer properties and be expanded spatially beyond typical point measures. This investigation used a multiscale approach to identify and quantify porosity distribution in the Miami Limestone, the lithostratigraphic unit that composes the uppermost portions of the Biscayne Aquifer in Miami Dade County, Florida. At the meter scale, laboratory measures of porosity and dielectric permittivity were made on blocks of Miami Limestone using zero offset GPR, laboratory and digital image techniques. Results show good correspondence between GPR and analytical porosity estimates and show variability between 22 and 66 %. GPR measurements at the field scale 10-1000 m investigated the bulk porosity of the limestone based on the assumption that a directly measured water table would remain at a consistent depth in the GPR reflection record. Porosity variability determined from the changes in the depth to water table resulted in porosity values that ranged from 33 to 61 %, with the greatest porosity variability being attributed to the presence of dissolution features. At the larger field scales, 100 - 1000 m, fitting of hyperbolic diffractions in GPR common offsets determined the vertical and horizontal variability of porosity in the saturated subsurface. Results indicate that porosity can vary between 23 and 41 %, and delineate potential areas of enhanced recharge or groundwater / surface water interactions. This study shows porosity variability in the Miami Limestone can range from 22 to 66 % within 1.5 m distances, with areas of high macroporosity or karst dissolution features

  10. Analysis of medieval limestone sculpture from southwestern France and the Paris Basin by NAA

    SciTech Connect

    Holmes, L.; Harbottle, G.

    1994-12-31

    Compositional characterization of limestone from sources known to medieval craftsmen and from the monuments they built can be used in conjunction with stylistic and iconographic criteria to infer geographic origin of sculptures that have lost their histories. Limestone from 47 quarrying locations in France and from numerous medieval monuments have been subjected to neutron activation analysis (NAA) to form the nucleus of the Brookhaven Limestone Database. Even though the method and techniques of NAA are well established, this paper briefly summarizes the parameters and experimental conditions useful for determining those concentration variables for which limestone from different sources exhibits significant and reproducible differences.

  11. Limestones of western Newfoundland that magnetized before Devonian folding but after Middle Ordovician lithification

    SciTech Connect

    Hodych, J.P. )

    1989-01-01

    A positive fold test and a negative conglomerate test help determine when and how stable remanence was acquired in the Middle Ordovician Table Head Group limestones of the Port au Port Peninsula of Newfoundland. The limestones magnetized after lithification and incorporation as clasts into a Middle Ordovician breccia. Hence, the limestones do not carry a detrital or other primary remanence despite their very low conodont color alteration index. The remanence may be thermoviscous or diagenetic and was acquired before Devonian folding. This suggests the need for caution in interpreting paleomagnetic results from other early Paleozoic limestones whose remanence resides in magnetite of blocking temperature lower than 400C.

  12. Developmental Studies of Pretend Play.

    ERIC Educational Resources Information Center

    Golomb, Claire

    This paper briefly reports on a series of studies that explore the relationship between symbolic or pretend modes of reasoning and cognitive processes which underlie conservation of quantity. It is hypothesized that the mental transformations which the child makes while playing a game of make-believe, namely, the transformation from his original…

  13. Building Curriculum during Block Play

    ERIC Educational Resources Information Center

    Andrews, Nicole

    2015-01-01

    Blocks are not just for play! In this article, Nicole Andrews describes observing the interactions of three young boys enthusiastically engaged in the kindergarten block center of their classroom, using blocks in a building project that displayed their ability to use critical thinking skills, physics exploration, and the development of language…

  14. They Too Should Play.

    ERIC Educational Resources Information Center

    Hirst, Cyntha C.; Shelley, Eva Y.

    1989-01-01

    Children with mental retardation and multiple handicaps can effectively participate in play activities and games, but the experience must be structured for them. Techniques for organizing play activities involving handicapped and nonhandicapped children are offered. Examples of singles play, rotation play, and associative play are described. (JDD)

  15. Children's Play and Television.

    ERIC Educational Resources Information Center

    Powell, Mark

    2001-01-01

    Discusses adverse effects of FCC deregulation of children's television programming on children's play behavior. Discusses the difference between play and imitation, the role of high quality dramatic play in healthy child development, the popularity of war play, and use of toys to increase dramatic play. Considers ways to help children gain control…

  16. The Denial of Play.

    ERIC Educational Resources Information Center

    Sutton-Smith, Brian

    Well meaning parents and teachers often use children's play for the purposes of literacy and socialization. Yet, these attempts may deny play to children by subordinating play to some other concept. Evidence shows that even when parents play with their very young children they generally play games like shopping, cooking, and eating; whereas when…

  17. Regeneration of sulfated dolomite and limestone by reductive decomposition

    SciTech Connect

    Ersoy-Mericboyu, A.; Karatepe, N.; Kuecuekbayrak, S.; Kafa, S.; Guersoy, G.

    1999-08-01

    Regeneration properties of sulfated dolomite and limestone samples were investigated. Natural stones were first fully calcined at 1223 K in a gaseous atmosphere consisting of CO{sub 2} 15 vol. % and dry air 85 vol. %; second, sulfation of the calcines was achieved by reacting them with a gaseous mixture consisting of CO{sub 2} 15 vol. %, SO{sub 2} 0.35 vol. %, and a balance of dry air at 1223 K; last, sulfated calcines were regenerated at 1373 K by a reductive decomposition process. During regeneration a 3:1 volumetric ratio of CO{sub 2}/CO was maintained in the reducing gaseous atmosphere to minimize CaS formation. It has been found that for the five sulfation-generation cycles the reactivity of the limestone and dolomite samples remained at acceptable levels. Since the repeated sulfation-regeneration steps caused an important change on the crystal lattice, as compared to the fresh stones, sorbent reactivity was also changed.

  18. Hydrogeology of the gray limestone aquifer in southern Florida

    USGS Publications Warehouse

    Reese, Ronald S.; Cunningham, Kevin J.

    2000-01-01

    Results from 35 new test coreholes and aquifer-test, water-level, and water-quality data were combined with existing hydrogeologic data to define the extent, thickness, hydraulic properties, and degree of confinement of the gray limestone aquifer in southern Florida. This aquifer, previously known to be present only in southeastern Florida (Miami-Dade, Broward, and Palm Beach Counties) below, and to the west of, the Biscayne aquifer, extends over most of central-south Florida, including eastern and central Collier County and southern Hendry County; it is the same as the lower Tamiami aquifer to the north, and it becomes the water-table aquifer and the upper limestone part of the lower Tamiami aquifer to the west. The aquifer generally is composed of gray, shelly, lightly to moderately cemented limestone with abundant shell fragments or carbonate sand, abundant skeletal moldic porosity, and minor quartz sand. The gray limestone aquifer comprises the Ochopee Limestone of the Tamiami Formation, and, in some areas, the uppermost permeable part of an unnamed formation principally composed of quartz sand. Underlying the unnamed formation is the Peace River Formation of the upper Hawthorn Group, the top of which is the base of the surficial aquifer system. Overlying the aquifer and providing confinement in much of the area is the Pinecrest Sand Member of the Tamiami Formation. The thickness of the aquifer is comparatively uniform, generally ranging from 30 to 100 feet. The unnamed formation part of the aquifer is up to 20 feet thick. The Ochopee Limestone accumulated in a carbonate ramp depositional system and contains a heterozoan carbonate-particle association. The principal rock types of the aquifer are pelecypod lime rudstones and floatstones and permeable quartz sands and sandstones. The pore types are mainly intergrain and separate vug (skeletal-moldic) pore spaces. The rock fabric and associated primary and secondary pore spaces combine to form a dual diffuse

  19. Rare earths in the Leadville Limestone and its marble derivates

    USGS Publications Warehouse

    Jarvis, J.C.; Wildeman, T.R.; Banks, N.G.

    1975-01-01

    Samples of unaltered and metamorphosed Leadville Limestone (Mississippian, Colorado) were analyzed by neutron activation for ten rare-earth elements (REE). The total abundance of the REE in the least-altered limestone is 4-12 ppm, and their distribution patterns are believed to be dominated by the carbonate minerals. The abundances of the REE in the marbles and their sedimentary precursors are comparable, but the distribution patterns are not. Eu is enriched over the other REE in the marbles, and stratigraphically upward in the formation (samples located progressively further from the heat source), the light REE become less enriched relative to the heavy REE. The Eu anomaly is attributed to its ability, unique among the REE, to change from the 3+ to 2+ oxidation state. Whether this results in preferential mobilization of the other REE or whether this reflects the composition of the pore fluid during metamorphism is unknown. Stratigraphically selective depletion of the heavy REE may be attributed to more competition for the REE between fluid and carbonate minerals in the lower strata relative to the upper strata. This competition could have been caused by changes in the temperature of the pore fluid or to the greater resistance to solution of the dolomite in the lower parts of the formation than the calcite in the upper parts. ?? 1975.

  20. Reactivation properties of four long-term sulfated limestones

    SciTech Connect

    Yinghai Wu; Edward J. Anthony; Lufei Jia

    2006-12-15

    Four Canadian limestones - Cadomin, Havelock, Kelly Rock, and Graymont - were investigated for their reactivation properties after long-term sulfation. Each limestone was initially sulfated with 1% SO{sub 2} at 850{sup o}C in a tube furnace for a relatively long time (about 16 h), to achieve an effectively maximally sulfated sample. The samples were subsequently hydrated with liquid water and steam at various conditions to reactivate the unreacted CaO. The hydrated samples were resulfated in a thermogravimetric analyzer for 90 min to evaluate the effect of hydration on the resulfation step. All four samples were significantly reactivated by steam hydration, which was much more effective than was hydration with liquid water, and the overall calcium utilization increased to 80-90% after reactivation, compared to 25-45% typical before reactivation. A scanning electron microscope was used to analyze Cadomin and Havelock samples, and both were uniformly sulfated before hydration. This work indicated that the uniformly sulfated samples could be reactivated given suitable hydration conditions.

  1. Treatment of mining acidic leachates with indigenous limestone, Zimapan Mexico.

    PubMed

    Labastida, I; Armienta, M A; Lara-Castro, R H; Aguayo, A; Cruz, O; Ceniceros, N

    2013-11-15

    An experimental study to evaluate the potential of using indigenous limestones in a passive system to treat acid mine drainage, at a mining zone of Mexico was carried out. Chemical and mineralogical characteristics of four types of native rocks (KIT1, KIT2, KSS, QZ) showed distinct CaCO3 contents. Synthetic aqueous leachates from an old tailings impoundment had a pH of 2.18, 34 mg/L As, 705 mg/L Fetotal, and 3975 mg/L SO4(2-). To evaluate dissolution behavior of rocks, kinetic batch experiments with an acid Fe-rich solution were performed. Decaying kinetic constants adjusting H(+) concentration to a first order exponential process were: KIT1 (k = 2.89), KIT2 (k = 0.89) and KSS (k = 0.47). Infrared spectrum and XRD of precipitates showed schwertmannite formation. To determine As and heavy metals (Fe, Cd, Zn, Al) removal from the synthetic leachates, batch experiments using KIT1 were developed. Arsenic decreased from 34.00 mg/L to 0.04 mg/L, Fe and Al were totally removed, and concentrations of Zn and Cd decreased 88% and 91% respectively. Analyses by IR and SEM-EDS indicate that co-precipitation with Fe-Hydroxides formed upon leachate interaction with limestone is the main As removal process. Chamosite, identified by XRD may participate in the removal of Al, SiO2 and a fraction of Fe.

  2. Dust resuspension characteristics over several quarries of limestone

    NASA Astrophysics Data System (ADS)

    Mandija, F.; Vila, F.

    2012-04-01

    One of the most important physical properties of the soil on ground surface is its ability to be involved on dust resuspension influenced by mechanical processes. Dust resuspension process depends on several factors. Some of them are soil properties, soil moisture, vegetation, paved/unpaved state, as well as the type of mechanical process, like wind, traffic, etc. Taking into consideration all these soil properties and environmental factors we determine dust resuspension rate. In this study we have conducted measurements on aerosol size distributions over several dust types, on different meteorological conditions. Aerosol size distributions measured on our measurements belong to sub-micrometric and micrometric size ranges. This is the size range which is the most influenced by resuspension processes. Places where there are carried out the experimental measurements are limestone quarries. Experimental procedure was conducted under fair weather meteorological conditions. Overall results of our measurements give valuable information about the ability of these soils to be involved on dust resuspension processes. The comparison of the concentrations of particulate matter over investigated areas indicates the contributions of different soil properties on dust resuspension process. In short, this study helps also on the estimation of air pollution on the areas with different soil types. These results let to estimate the real contribution of the activities carried on limestone quarries on aerosol number concentrations.

  3. Characterizing and modelling 'ghost-rock' weathered limestones

    NASA Astrophysics Data System (ADS)

    Dubois, Caroline; Goderniaux, Pascal; Deceuster, John; Poulain, Angélique; Kaufmann, Olivier

    2016-04-01

    'Ghost-rock' karst aquifer has recently been highlighted. In this particular type of aquifer, the karst is not expressed as open conduits but consists in zones where the limestone is weathered. The in-situ weathering of limestone leaves a soft porous material called 'alterite'. The hydro-mechanical properties of this material differs significantly from those of the host rock: the weathering enhances the storage capacity and the conductivity of the rock. This type of weathered karst aquifer has never been studied from a hydrogeological point of view. In this study, we present the hydraulic characterization of such weathered zones. We also present a modelling approach derived from the common Equivalent Porous Medium (EPM) approach, but including the spatial distribution of hydrogeological properties through the weathered features, from the hard rock to the alterite, according to a weathering index. Unlike the Discrete Fracture Network (DFN) approaches, which enable to take into account a limited number of fractures, this new approach allows creating models including thousands of weathered features. As the properties of the alterite have to be considered at a centimeter scale, it is necessary to upscale these properties to carry out simulations over large areas. Therefore, an upscaling method was developed, taking into account the anisotropy of the weathered features. Synthetic models are built, upscaled and different hydrogeological simulations are run to validate the method. This methodology is finally tested on a real case study: the modelling of the dewatering drainage flow of an exploited quarry in a weathered karst aquifer in Belgium.

  4. Treatment of mining acidic leachates with indigenous limestone, Zimapan Mexico.

    PubMed

    Labastida, I; Armienta, M A; Lara-Castro, R H; Aguayo, A; Cruz, O; Ceniceros, N

    2013-11-15

    An experimental study to evaluate the potential of using indigenous limestones in a passive system to treat acid mine drainage, at a mining zone of Mexico was carried out. Chemical and mineralogical characteristics of four types of native rocks (KIT1, KIT2, KSS, QZ) showed distinct CaCO3 contents. Synthetic aqueous leachates from an old tailings impoundment had a pH of 2.18, 34 mg/L As, 705 mg/L Fetotal, and 3975 mg/L SO4(2-). To evaluate dissolution behavior of rocks, kinetic batch experiments with an acid Fe-rich solution were performed. Decaying kinetic constants adjusting H(+) concentration to a first order exponential process were: KIT1 (k = 2.89), KIT2 (k = 0.89) and KSS (k = 0.47). Infrared spectrum and XRD of precipitates showed schwertmannite formation. To determine As and heavy metals (Fe, Cd, Zn, Al) removal from the synthetic leachates, batch experiments using KIT1 were developed. Arsenic decreased from 34.00 mg/L to 0.04 mg/L, Fe and Al were totally removed, and concentrations of Zn and Cd decreased 88% and 91% respectively. Analyses by IR and SEM-EDS indicate that co-precipitation with Fe-Hydroxides formed upon leachate interaction with limestone is the main As removal process. Chamosite, identified by XRD may participate in the removal of Al, SiO2 and a fraction of Fe. PMID:22819958

  5. Bird Species Diversity in the Padawan Limestone Area, Sarawak

    PubMed Central

    Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd; Koon, Lim Chan; Rahman, Mustafa Abdul

    2011-01-01

    Bird surveys were conducted in the Padawan Limestone Area for seven days at each of two study sites, Giam and Danu, from August to December 2008. The purpose of the study was to compare the area’s bird species richness and abundance of bird species in other limestone areas and in other forest types. The study also compared the species richness and relative abundance of birds in undisturbed and disturbed areas at both study sites. Twenty mist nets were deployed for 12 hours daily. During this study period, direct observations of birds were also made. In all, 80 species from 34 families were recorded at both sites. At Giam, 120 birds were mist-netted. These birds represented 31 species from 16 families. The direct observations at Giam recorded 13 species from 11 families. In the undisturbed area, 21 species from 13 families were mist-netted, whereas in the disturbed area, 21 species from 10 families were mist-netted. In Danu, a total of 48 birds, representing 25 species from 12 families, were mist-netted. The observations at Danu recorded 34 species from 19 families. Twelve species from 7 families were mist-netted in the undisturbed area, whereas 18 species from 11 families were mist-netted in the disturbed area. Statistical analysis showed that the species diversity index differed significantly between undisturbed and disturbed areas. PMID:24575218

  6. Children's Gendered Drawings of Play Behaviours

    ERIC Educational Resources Information Center

    Akseer, Tabasum; Lao, Mary Grace; Bosacki, Sandra

    2012-01-01

    According to child psychologists, vital links exist between children's drawings and their emotional, social, and cognitive development. Previous research has explored the important relations between drawings and play in educational settings. Given the vast research that explores the ambiguous topic of children's play, according to Richer (1990),…

  7. Colmenar limestone as a resource for built heritage

    NASA Astrophysics Data System (ADS)

    Fort, Rafael; Álvarez de Buergo, Mónica; Varas-Muriel, MªJosé; Mercedes Pérez-Monserrat, Elena

    2013-04-01

    The Colmenar stone (or Colmenar limestone) has been used in the construction of significant builidings of the Central area of Spain, such as the Royal Palace of Aranjuez (16th -18th centuries) or the Royal Palace of Madrid (18th century). Nowadays this building stone is still widely used, both for new construction and restoration works, as well as for the indoor ornamentation of emblematic buildings such as the Royal Theater of Madrid (20th century). There are many quarries from where this stone was exploited, being the most prestigious ones those located in Colmenar de Oreja, at 50 km Southeast the city of Madrid. The high quality of the stone in these quarries, its whiteness and pureness, made this locality the most relevant in these stonés extractive activities, concentrating the most relevant exploitations and providing the stone the denomination of the municipality (Colmenar). It was an underground mining extraction until the 20th century in order to reach the highest quality level of the mine, the so called "Banco Gordo" (Thick Bank). Generically known as moorland limestone, this rock belongs to the fluvial-lacustrine carbonates of the Upper Miocene Unit of the Tertiary Madrid's Basin. Its tonality mainly ranges from white to cream and even light grey. Under a petrographic point of view, this limestone is constituted by 40% of bioclasts (characea, ostracods and gasteropods), 20-30% of micritic matrix and 30-40% of sparitic cement. Therefore, it can be classified as a biomicrite/biosparite limestone or as a bioclastic packstone. Some particularities of these limestones regarding their appearance are related to some karstic processes they underwent linked to some dissolution phenomena during the Pliocene. All of this resulted on an abundance of cavities with terra rossa fillings, a non-soluble clayey residue, iron enriched, which is the responsible for the reddish and pinkish color that the Colmenar stone sometimes shows. These petrographic characteristics

  8. Vertical distribution of soil organic carbon in limestone Mediterranean mountains areas, southern Spain

    NASA Astrophysics Data System (ADS)

    Gil, Juan; Jordan, Antonio; Martínez-Zavala, Lorena; Parras-Alcántara, Luis; Lozano-García, Beatriz

    2015-04-01

    Normally, soil organic carbon (SOC) investigations are related to fertility and/or soil quality so refer to surface horizon. In other cases, soil control sections or soil horizons are used to study soil carbon pool, especially in forest areas. In this line, in order to provide quantitative data of organic carbon in soils and sediments in relation to depth, the organic carbon vertical distribution was studied in selected areas of southern Spain. Significant variations in depth of organic carbon may be related with different vegetation and/or land use changes, so it can be used to select sampling points for studying these changes through pollen analysis. For this study, ten sinkholes in hard limestone Mediterranean mountains areas of southern Spain have been selected following scientific interest criteria and/or minimal human influence. Soil and sediment samples extraction was carried out using tensile steel drills up to four meters in deep driven by an electric striking hammer. Once extracted the soil columns, soil control sections are taken every 5 cm, obtaining 470 samples in the ten sinkholes selected and making four replications for each soil control section. The soil and sediments exploration in different sinkholes highlights the karst heterogeneity formations, especially in terms of its depth. Thus, it was possible to take samples of varying depth, ranging between 1 and 5 m, being the limiting factor the hard pan forming which can be soil nature (petrocalcic horizon) or lithological nature (hard limestone). SOC in every sampling point varied between 2.5 and 16.7 g kg-1. In general, SOC concentrations decreases progressively in depth, although in some sampling point 10 g kg-1 were obtained at 200 cm in depths. On the other hand, it had been observed significant increases at 100 cm in deep, sometimes repeating at high deep, which could be related to ancient sedimentary past or with edaphogenic processes past. Definitely more comprehensive studies could shed new

  9. Deep-to-shallow carbonate ramp transition in Viola Limestone (Ordovician), southwest Arbuckle Mountains, Oklahoma

    SciTech Connect

    Glavin, P.K.

    1983-03-01

    The Viola Limestone (Middle and Upper Ordovician) of the southwest Arbuckle Mountains was deposited on a carbonate ramp within the southern Oklahoma Aulacogen. Depositional environments include (1) anaerobic, deep-ramp setting represented by microfacies RL, CH, CGL, and A, (2) dysaerobic, mid-ramp setting represented by microfacies B, and (3) aerobic, shallow-ramp setting represented by microfacies C and D. Deposition in the deep- and mid-ramp environments was dominated by bottom-hugging currents produced by off-platform flow of denser waters. Primary sedimentary structures include millimeter-size laminations, starved ripples, and concave-up and inclined erosional surfaces. Shelly benthic fauna are rare in A and B; trace fossils are common only in B. Deposits associated with the line-source gully, microfacies RL, CH, and CGL, are laterally confined; they have been observed only in the southwest Arbuckle Mountains. Primary sedimentary structures present in RL include wavy and ripple-cross laminae. Microfacies CH, contained within RL and interpreted as a submarine channel deposit, is present only at one locality. Primary sedimentary structures present in CH include an erosional base and several internal erosional surfaces, lateral accretionary sets, and imbricated, locally derived intraclasts. High total organic carbon (TOC) values have been reported for the lower Viola. TOC values of 1% have been reported from microfacies A, and TOC values of 5% have been reported from microfacies RL. These high values suggest that A and RL may act as hydrocarbon source rocks. Recognition of these microfacies in the subsurface will contribute to our knowledge of the Viola Limestone as an exploration target.

  10. Geostatistical three-dimensional modeling of oolite shoals, St. Louis Limestone, southwest Kansas

    USGS Publications Warehouse

    Qi, L.; Carr, T.R.; Goldstein, R.H.

    2007-01-01

    In the Hugoton embayment of southwestern Kansas, reservoirs composed of relatively thin (<4 m; <13.1 ft) oolitic deposits within the St. Louis Limestone have produced more than 300 million bbl of oil. The geometry and distribution of oolitic deposits control the heterogeneity of the reservoirs, resulting in exploration challenges and relatively low recovery. Geostatistical three-dimensional (3-D) models were constructed to quantify the geometry and spatial distribution of oolitic reservoirs, and the continuity of flow units within Big Bow and Sand Arroyo Creek fields. Lithofacies in uncored wells were predicted from digital logs using a neural network. The tilting effect from the Laramide orogeny was removed to construct restored structural surfaces at the time of deposition. Well data and structural maps were integrated to build 3-D models of oolitic reservoirs using stochastic simulations with geometry data. Three-dimensional models provide insights into the distribution, the external and internal geometry of oolitic deposits, and the sedimentologic processes that generated reservoir intervals. The structural highs and general structural trend had a significant impact on the distribution and orientation of the oolitic complexes. The depositional pattern and connectivity analysis suggest an overall aggradation of shallow-marine deposits during pulses of relative sea level rise followed by deepening near the top of the St. Louis Limestone. Cemented oolitic deposits were modeled as barriers and baffles and tend to concentrate at the edge of oolitic complexes. Spatial distribution of porous oolitic deposits controls the internal geometry of rock properties. Integrated geostatistical modeling methods can be applicable to other complex carbonate or siliciclastic reservoirs in shallow-marine settings. Copyright ?? 2007. The American Association of Petroleum Geologists. All rights reserved.

  11. The Uses of Play

    ERIC Educational Resources Information Center

    Cabaniss, Thomas

    2005-01-01

    Teaching artists have techniques for keeping play alive and vital in their work. But how do they think of play as TAs? In this article, the author examines the role of play in the work and life of teaching artists.

  12. Making Theater: Developing Plays with Young People.

    ERIC Educational Resources Information Center

    Kohl, Herbert R.

    Intended for teachers who have no particular experience or training in teaching theater, but who have a love of theater and enjoy a good play, this book discusses making theater with children. It explores improvisation, reading and acting with scripts, adapting plays for young actors, and writing plays. The examples presented in the text are…

  13. Sand Play in the Primary Classroom.

    ERIC Educational Resources Information Center

    Ewing, Jan; Eddowes, E. Anne

    1994-01-01

    Examines the benefits of sand play for young children, focusing on areas of cognitive, physical, communicative, creative and social-emotional development. Also discusses the role of the teacher in encouraging children's natural curiosity and exploration with sand play, noting that teachers should observe and interact with children during play in…

  14. Children in Play, Story, and School.

    ERIC Educational Resources Information Center

    Goncu, Artin, Ed.; Klein, Elisa L.

    In honor of the contributions of Greta G. Fein to the fields of developmental psychology and early childhood education, a community of scholars prepared this volume to explore how social play arises, social play's developmental and educational significance, and the ways in which social play can be promoted in early childhood settings. In addition,…

  15. "The Woods Is a More Free Space for Children to Be Creative; Their Imagination Kind of Sparks out There": Exploring Young Children's Cognitive Play Opportunities in Natural, Manufactured and Mixed Outdoor Preschool Zones

    ERIC Educational Resources Information Center

    Zamani, Zahra

    2016-01-01

    Outdoor preschools are critical for children's play and development. Integrating observational and interview methods, this study examined four-to-five-year-old children's cognitive play experiences in an outdoor preschool with natural, mixed and manufactured zones. The observational results indicated that the natural and mixed zones offered a…

  16. Understanding Playful Pedagogies, Play Narratives and Play Spaces

    ERIC Educational Resources Information Center

    Goouch, Kathy

    2008-01-01

    This paper is a tentative attempt to unwrap and understand one aspect of playful practice and the influences which determine its existence in early years settings. "Storying" events, those occasions when teachers and children together "make up" stories or parts of stories, develop roles or co-construct fantasies, occur moment by moment in some…

  17. Crystallographic transformation of limestone during calcination under CO2.

    PubMed

    Valverde, Jose Manuel; Medina, Santiago

    2015-09-14

    The calcination reaction of limestone (CaCO3) to yield lime (CaO) is at the heart of many industrial applications as well as natural processes. In the recently emerged calcium-looping technology, CO2 capture is accomplished by the carbonation of CaO in a gas-solid reactor (carbonator). CaO is derived by the calcination of limestone in a calciner reactor under necessarily high CO2 partial pressure and high temperature. In situ X-ray diffraction (XRD) has been employed in this work to gain further insight into the crystallographic transformation that takes place during the calcination of limestone under CO2, at partial pressures (P) close to the equilibrium pressure (Peq) and at high temperature. Calcination under these conditions becomes extremely slow. The in situ XRD analysis presented here suggests the presence of an intermediate metastable CaO* phase stemming from the parent CaCO3 structure. According to the reaction mechanism proposed elsewhere, the exothermicity of the CaO* → CaO transformation and high values of P/Peq inhibit the nucleation of CaO at high temperatures. The wt% of CaO* remains at a relatively high level during slow calcination. Two diverse stages have been identified in the evolution of CaO crystallite size, L. Initially, L increases with CaCO3 conversion, following a logarithmic law. Slow calcination allows the crystallite size to grow up from a few nanometers at nucleation up to around 100 nm near the end of conversion. Otherwise, quick calcination at relatively lower CO2 concentrations limits CaO crystallite growth. Once calcination reaches an advanced state, the presence of CaO* drops to zero and the rate of increase of the CaO crystallite size is significantly hindered. Arguably, the first stage in CaO crystallite growth is driven by aggregation of the metastable CaO* nanocrystals, due to surface attractive forces, whereas the second one is consistent with sintering of the aggregated CaO crystals, and persists with time after full

  18. Crystallographic transformation of limestone during calcination under CO2.

    PubMed

    Valverde, Jose Manuel; Medina, Santiago

    2015-09-14

    The calcination reaction of limestone (CaCO3) to yield lime (CaO) is at the heart of many industrial applications as well as natural processes. In the recently emerged calcium-looping technology, CO2 capture is accomplished by the carbonation of CaO in a gas-solid reactor (carbonator). CaO is derived by the calcination of limestone in a calciner reactor under necessarily high CO2 partial pressure and high temperature. In situ X-ray diffraction (XRD) has been employed in this work to gain further insight into the crystallographic transformation that takes place during the calcination of limestone under CO2, at partial pressures (P) close to the equilibrium pressure (Peq) and at high temperature. Calcination under these conditions becomes extremely slow. The in situ XRD analysis presented here suggests the presence of an intermediate metastable CaO* phase stemming from the parent CaCO3 structure. According to the reaction mechanism proposed elsewhere, the exothermicity of the CaO* → CaO transformation and high values of P/Peq inhibit the nucleation of CaO at high temperatures. The wt% of CaO* remains at a relatively high level during slow calcination. Two diverse stages have been identified in the evolution of CaO crystallite size, L. Initially, L increases with CaCO3 conversion, following a logarithmic law. Slow calcination allows the crystallite size to grow up from a few nanometers at nucleation up to around 100 nm near the end of conversion. Otherwise, quick calcination at relatively lower CO2 concentrations limits CaO crystallite growth. Once calcination reaches an advanced state, the presence of CaO* drops to zero and the rate of increase of the CaO crystallite size is significantly hindered. Arguably, the first stage in CaO crystallite growth is driven by aggregation of the metastable CaO* nanocrystals, due to surface attractive forces, whereas the second one is consistent with sintering of the aggregated CaO crystals, and persists with time after full

  19. The Play of Psychotherapy

    ERIC Educational Resources Information Center

    Marks-Tarlow, Terry

    2012-01-01

    The author reviews the role of play within psychotherapy. She does not discuss the formal play therapy especially popular for young children, nor play from the Jungian perspective that encourages the use of the sand tray with adults. Instead, she focuses on the informal use of play during psychotherapy as it is orchestrated intuitively. Because…

  20. 76 FR 35396 - Black Hills National Forest, Mystic Ranger District, South Dakota, Section 30 Limestone Mining...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-17

    ... Mining Project AGENCY: Forest Service, USDA. ACTION: Corrected Notice of intent to prepare an... the purpose of mining for chemical grade limestone within mining claims on National Forest System land... publication dates. A Notice of Availability for the Section 30 Limestone Mining Project Draft EIS...

  1. Adsorption and desorption of phosphate on limestone in experiments simulating seawater intrusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The absorption and desorption of phosphorus on a large block of limestone was investigated using deionized water (DIW) and seawater. The limestone had a high affinity to adsorb phosphorus in DIW. Phosphate adsorption was significantly less in seawater, and more phosphorus was desorbed in the seawate...

  2. OPTIMIZATION OF A PULSED LIMESTONE BED REACTOR AT THE ARGO TUNNEL IN IDAHO SPRINGS, COLORADO

    EPA Science Inventory

    Acid Mine Drainage (AMD) is an unintended consequence of coal and metal mining that adversely affects thousands of miles of streams both in the eastern and western regions of the U.S. A novel AMD treatment process based on limestone based on limestone neutralization has been dev...

  3. STEAM ENHANCED REMEDIATION RESEARCH FOR DNAPL IN FRACTURED ROCK, LORING AIR FORCE BASE, LIMESTONE, MAINE

    EPA Science Inventory

    This report details a research project on Steam Enhanced Remediation (SER) for the recovery of volatile organic compounds from fractured limestone that was carried out at the Quarry at the former Loring Air Force Base in Limestone, Maine. This project was carried out by USEPA, Ma...

  4. Stratigraphy and depositional history of the West Franklin Limestone (Pennsylvanian) in the southernmost part of the Illinois Basin, western Kentucky

    SciTech Connect

    King, N.R. . Dept. of Geosciences)

    1994-04-01

    The West Franklin Limestone in the subsurface of Webster and Union Counties, Kentucky includes 7.5--18m of strata deposited during portions of four depositional cycles in the latest Desmoinesian and earliest Missourian (Pennsylvanian). These cycles began with marine flooding and deposition of limestone, followed by progradation of siliciclastics in three of the four cycles, and ended with emergence. The basal West Franklin is micritic limestone (0.5--3m) that rests on rooted mudstone. Overlying the limestone are siliciclastics (1.5--7m) dominated by red and green claystone that is rooted at the top. Next is a middle limestone zone that includes either a paleokarsted micritic limestone, or a thin bioclastic micritic limestone bed associated with phosphatic shale and locally a second bioclastic micritic limestone. Above that is another siliciclastic interval (4--9m) capped by rooted mudstone and locally a thin coal. The overlying micritic limestone (1.5--2.5m) marks the top of the West Franklin. Depositional events included: (1) marine flooding of an emergent shelf producing the basal limestone; (2) progradation of siliciclastics followed by emergence and paleosol development; (3) marine flooding producing a second limestone; (4) emergence and karstification of erosional remnants of the second limestone; (5) renewed marine flooding depositing shell hash'' limestones and phosphatic shale; (6) progradation of siliciclastics culminating in emergency; and (7) marine flooding producing the upper limestone. Thus, two flooding-emergence cycles are represented by the middle limestone zone. The second, locally-developed shell-hash'' limestone in the middle zone was deposited during the regressive phase of a depositional cycle. All of the other limestones were deposited during transgression.

  5. Geophysical Monitoring of CO2Injections in Decimetric Limestone Samples

    NASA Astrophysics Data System (ADS)

    Contraires, S.; Vialle, S.; Zamora, M.; Lopez, O.; Zuddas, P.

    2007-05-01

    Within the framework of the fight against greenhouse gases emissions, one of the adopted solutions is the carbon dioxide sequestration. Injections of this gas in underground reservoir will acidify the fluid saturating the pores of the rock, which can then react with the porous matrix. The fluid-rock interactions consisting on both dissolution and precipitation reactions may modify porosity and permeability of the reservoir. Monitoring, during the injection and storage phase, will be required to detect possible leaks through the geologic strata overlaying the reservoir or modifications of its hydraulic properties. Among the available monitoring methods, geophysical techniques appear particularly adapted. In order to quantify the effect of dissolution reaction on the geophysical observables, we performed laboratory experiments on decimetric limestone samples (10 cm diameter and 30 cm length). A CO2saturated fluid percolated throughout the sample. During the experiments the core is placed into an original percolation device allowing to measure in situ and continuously different physical parameters (permeability, pH, electrical conductivity of both rock and fluid) during the solution flow through a sample. The output fluid was regularly sampled and the fluid chemical composition was analyzed. In addition, the P- and S-waves velocities and attenuations were measured along the sample (each centimeter) regularly. The results of the experiments, where a limestone reacts with CO2saturated reactive fluid (pH=4), reaching a one order of magnitude permeability increase, show that the seismic waves velocity and attenuation measurements allow us to follow the evolution of the porosity along the sample. The 3% increase of the porosity and the creation of preferential flow paths (wormholes), detected by the seismic study, are in agreement with the X-ray Computed Tomography (CT), the variations of the electrical formation factor, and the chemical analyses of the output fluid.

  6. Thermal strengthening of limestone: monument preservation during fire

    NASA Astrophysics Data System (ADS)

    Heap, Michael; Lavallee, Yan; Benson, Philip; Hess, Kai-Uwe; Dingwell, Donald

    2010-05-01

    The use of natural rocks in the construction of buildings and monuments predates the use of commercially engineered materials such as concrete. Such building material can be subject to elevated temperatures in the misfortunate event of a fire. In civil engineering, it is generally appreciated that the strength of rock is decreased when it is or has been exposed to elevated temperatures. This is due the formation of thermal microcracks, a result of the thermal expansion mismatch between different minerals in the rock. Even today, fire is by no means an uncommon occurrence and approximately one historic building is lost to fire in the European Union every day (COST C17 2001). A large number of historically significant buildings and monuments are constructed from carbonate material. However, could the paradigm of thermal weakening of limestone construction material be in part, a paradox? We report new findings on the thermal strengthening of the Solnhofen limestone (Solnhofen, Germany), a carbonate rock traditionally used in construction of building and statues in central Europe. Two types of deformation experiments were performed to investigate: (1) the strength of samples at elevated temperatures (i.e. during fire) and (2) the strength of samples at room temperature after heat-treatment (i.e. after fire). During experimentation, microcracking was monitored by the output of acoustic emissions (AE). Thermo-gravimetric (TG) analysis was also undertaken to measure the mass loss during heating. For the experiments ‘during fire', samples were heated to temperatures of 25°, 200°, 400°, 500°, 600°, 650° and 800°C at a controlled rate of 5°C/min and deformed until failure in a uniaxial press at a constant strain rate of 10-5 s-1. For the experiments ‘after fire', samples were heat-treated to each 100°C increment up to 800°C, they were then cooled at the same rate and their strength tested at room temperature. The mechanical data demonstrate that, during fire

  7. Geochemical controls on phosphatic carbonate deposition: A case study of the Cambrian Thorntonia Limestone, southern Georgina Basin, Australia

    NASA Astrophysics Data System (ADS)

    Creveling, J. R.; Johnston, D. T.; Poulton, S.; Kotrc, B.; Marz, C.; Schrag, D. P.; Knoll, A.

    2012-12-01

    Phosphorite and phosphatic carbonate define a spectrum of sedimentary lithologies enriched in authigenic apatite. The punctuated temporal distribution (Cook and McElhinny, 1979) and evolving spatial distribution (Brasier and Callow, 2007) of phosphates through Earth history suggest that unique and restrictive physio-chemical conditions govern the formation of authigenic apatite in time and space. A global phosphogenic episode that coincides with major evolutionary changes across the Ediacaran—Cambrian boundary (Cook, 1992) preserves a detailed record of early animal diversification (e.g., Dornbos, 2010). Phosphorus is a limiting nutrient for biological productivity. Thus, changes in the source and/or sink of this element have been invoked to explain fluctuations in organic carbon burial and oxidant accumulation over this interval. What conditions and mechanisms controlled the opening and closure of the global Ediacaran-Cambrian phosphogenic window? We present sedimentological, petrographic, and geochemical data from the Cambrian Series 2-3 Thorntonia Limestone, Georgina Basin, Australia, one of the youngest Cambrian localities displaying widespread apatite nucleation and exceptional phosphatic preservation of small shelly fossils. Integrated with sedimentology, geochemical data—iron and phosphorus speciation data, stable carbon isotopes and trace element concentrations—provide a basin-scale environmental context for interpreting phosphate deposition. Phosphorus enrichment occurred during times of expanded anoxic, ferruginous conditions in subsurface water masses. This suggests that, in addition to organic matter delivery, phosphorus adsorbed to, and co-precipitated with, iron minerals forming in the water column provided a significant source to sediments. Sedimentary organic matter played a second important role, ensuring anoxic pore water conditions needed to remobilize phosphorus from primary sources within accumulating carbonates. Petrology reveals that

  8. Hydration mechanisms of ternary Portland cements containing limestone powder and fly ash

    SciTech Connect

    De Weerdt, K.; Haha, M. Ben; Le Saout, G.; Kjellsen, K.O.; Justnes, H.; Lothenbach, B.

    2011-03-15

    The effect of minor additions of limestone powder on the properties of fly ash blended cements was investigated in this study using isothermal calorimetry, thermogravimetry (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques, and pore solution analysis. The presence of limestone powder led to the formation of hemi- and monocarbonate and to a stabilisation of ettringite compared to the limestone-free cements, where a part of the ettringite converted to monosulphate. Thus, the presence of 5% of limestone led to an increase of the volume of the hydrates, as visible in the increase in chemical shrinkage, and an increase in compressive strength. This effect was amplified for the fly ash/limestone blended cements due to the additional alumina provided by the fly ash reaction.

  9. Lithology and strontium distribution of De Queen limestone at main Highland Gypsum Quarry, Highland, Arkansas

    SciTech Connect

    Slaughter, T.A.; Ledger, E.B.; Sartin, A.A.

    1987-09-01

    The De Queen Limestone (Comanchean, Cretaceous) in the main Highland Gypsum quarry at Highland, Arkansas, consists of gypsum, limestone, and clastic sediments deposited along the landward margin of a broad, restricted, shallow lagoon. It grades downdip into the Ferry Lake Anhydrite. Gypsum, in the form of satin spar, selenite, and alabaster, is abundant in the lower part of the section. Limestones ranging from lime mudstones to grainstones contain fossil mollusks, ostracods, serpulid worm tubes, and foraminifera. The gypsum and limestone lithologies are interbedded with claystones and shales. Strontium concentration was determined on about 100 samples by x-ray fluorescence spectrometry (XRF) and was found to be controlled by diagenesis, not deposition. Strontium concentrations in the gypsum are likely controlled by the rate of recrystallization of secondary anhydrite. Levels of strontium in the limestones reflect the amount of celestite cement. The strontium content of the clastic beds correlates with the amount of strontium-rich microcrystals of strontianite, celestite, barite, and witherite.

  10. EPRI High-Sulfur Test Center: Wet flue gas desulfurization baseline limestone tests

    SciTech Connect

    Gray, S.M.; Burke, J.M.

    1990-10-01

    This report presents the results of the Baseline Limestone Test Program conducted at Electric Power Research Institute's (EPRI) High Sulfur Test Center (HSTC). The objective of this program was to characterize wet limestone FGD system performance as a function of basic FGD design and operating variables using the pilot system at the HSTC. The results from this program will be useful in optimizing existing wet limestone FGD systems, and will provide the foundation for more specific research to be conducted at the HSTC. The design and operating variables that were investigated include: inlet SO{sub 2} concentration, liquid-to-gas ratio, slurry pH and density, dissolved calcium concentration, reaction tank volume, limestone grind, and in-situ forced oxidation. Results illustrate the effect of these variables on SO{sub 2} removal efficiency, limestone utilization, sulfite oxidation, and the waste solids properties. 20 refs., 58 figs., 19 tabs.

  11. Toxicity of acid mine pit lake water remediated with limestone and phosphorus

    SciTech Connect

    Neil, L.L.; McCullough, C.D.; Lund, M.A.; Evans, L.H.; Tsvetnenko, Y.

    2009-11-15

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH similar to 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  12. Shallow-water limestones within the Paleogene forearc basin of California: Unique paleogeographic indicators

    SciTech Connect

    Whidden, K.J.; Bottjer, D.J.; Lund, S.P. . Dept. of Geological Sciences)

    1992-01-01

    A number of shallow-water limestones have recently been documented in late Mesozoic/Paleogene forearc strata of the Cordilleran continental arc. These limestones occur on two different tectonic blocks which were both developed within the forearc basin and subsequently moved relative to one another due to oblique convergence since Late Cretaceous time. Faunal evidence suggests that these limestones were deposited within the photic zone, at shelfal depths. Each limestone represents part or all of the basal Paleogene sequence; they are intercalated with or overlain by deeper-water strata. One region of outcrops in the western Santa Monica Mountains is latest Paleocene in age, while the other region, in the eastern Santa Ynez Mountains and Wheeler Gorge area, is early Eocene in age. These shallow-water limestones may be used as paleogeographic indicators, as they represent relative topographic highs within the basin. The microplate tectonic reconstruction of Hornafius (1985) suggests that the limestones occur on opposite sides of a north-south trending trough within the overall forearc basin. The Paleocene limestones, which occur along the eastern margin of the trough, are intercalated with marine shales and may represent small fluctuations in relative sea level and/or sediment supply on a topographic high. The Eocene limestones, which occur along the western side of the trough, are always the basal Paleogene unit deposited on tilted Cretaceous strata or Franciscan rocks and overlain by deeper-water shales. The occurrence of Franciscan as basement for limestone deposition implies localized tectonic uplift within the forearc. Each of these limestones probably represents initiation of a single period of relative sea level rise, as the basal shallow-water carbonates were eventually overwhelmed by deeper-water shales. Thus two episodes of carbonate deposition allow for the delineation of two topographic highs within the Paleogene forearc basin.

  13. Characterization of the enhancement effect of Na2CO3 on the sulfur capture capacity of limestones.

    PubMed

    Laursen, Karin; Kern, Arnt A; Grace, John R; Lim, C Jim

    2003-08-15

    It has been known for a long time that certain additives (e.g., NaCl, CaCl2, Na2CO3, Fe2O3) can increase the sulfur dioxide capture-capacity of limestones. In a recent study we demonstrated that very small amounts of Na2CO3 can be very beneficial for producing sorbents of very high sorption capacities. This paper explores what contributes to these significant increases. Mercury porosimetry measurements of calcined limestone samples reveal a change in the pore-size from 0.04-0.2 microm in untreated samples to 2-10 microm in samples treated with Na2CO3--a pore-size more favorable for penetration of sulfur into the particles. The change in pore-size facilitates reaction with lime grains throughout the whole particle without rapid plugging of pores, avoiding premature change from a fast chemical reaction to a slow solid-state diffusion controlled process, as seen for untreated samples. Calcination in a thermogravimetric reactor showed that Na2CO3 increased the rate of calcination of CaCO3 to CaO, an effect which was slightly larger at 825 degrees C than at 900 degrees C. Peak broadening analysis of powder X-ray diffraction data of the raw, calcined, and sulfated samples revealed an unaffected calcite size (approximately 125-170 nm) but a significant increase in the crystallite size for lime (approximately 60-90 nm to approximately 250-300 nm) and less for anhydrite (approximately 125-150 nm to approximately 225-250 nm). The increase in the crystallite and pore-size of the treated limestones is attributed to an increase in ionic mobility in the crystal lattice due to formation of vacancies in the crystals when Ca is partly replaced by Na.

  14. Role-Playing Mitosis.

    ERIC Educational Resources Information Center

    Wyn, Mark A.; Stegink, Steven J.

    2000-01-01

    Introduces a role playing activity that actively engages students in the learning process of mitosis. Students play either chromosomes carrying information, or cells in the cell membrane. (Contains 11 references.) (Author/YDS)

  15. Play Is the Way

    ERIC Educational Resources Information Center

    Gross, Steve; Sanderson, Rebecca Cornelli

    2012-01-01

    Historically, play has been viewed as a frivolous break from important endeavors like working and learning when, in fact, a child's ability to fully and freely engage in play is essential to their learning, productivity, and overall development. A natural drive to play is universal across all young mammals. Children from every society on earth…

  16. Dimensions of Infant Play.

    ERIC Educational Resources Information Center

    Fenson, Larry

    Changes in manipulative play with objects were examined in a longitudinal sample of 10 boys and 9 girls tested at ages 9, 13, and 18 months. Stability of individual differences in play was also examined. Each child was observed individually for 7 minutes in a room in which a tea set was the only toy present. Seven types of play behavior were…

  17. The Pedagogy of Play

    ERIC Educational Resources Information Center

    Giesbrecht, Sheila

    2012-01-01

    Play is important. Environmental educators Sobel and Louv write about the relationship between children and outside play and suggest that early transcendental experiences within nature allow children to develop empathetic orientations towards the natural world. Children who play out-of-doors develop an appreciation for the environment and…

  18. The Importance of Play.

    ERIC Educational Resources Information Center

    Sher, Allen

    Play is the spontaneous or organized recreational activity of children; it is at the heart of the preschool curriculum. Play aids in the development of physical, intellectual, and social skills. Children's play progresses through three developmental stages: solitary, parallel, and social. Preschool teachers should arrange for four kinds of…

  19. Literacy through Play.

    ERIC Educational Resources Information Center

    Owocki, Gretchen

    When young children play in a purposefully designed, literacy-rich environment, teachers can discover and capitalize on teachable moments. This book discusses how children develop literacy and how early childhood teachers use play and other child-centered experiences to facilitate literacy development. Chapter 1, "Play and Developmentally…

  20. Play, Policy & Practice.

    ERIC Educational Resources Information Center

    Klugman, Edgar, Ed.

    In 1992, the U.S.-Israel Binational Science Foundation (BSF), in conjunction with Wheelock College (Boston), sponsored its second workshop on children's play, entitled "Play and Cognitive Ability: The Cultural Context." This volume reflects the presentations and discussions held at the workshop, offering perspectives on children's play that, taken…

  1. 77 FR 60458 - Public Land Order No. 7803; Withdrawal of Public Lands for the Limestone Hills Training Area; MT

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-03

    ... hours. SUPPLEMENTARY INFORMATION: The Limestone Hills Training Area withdrawal will maintain the current... Bureau of Land Management Public Land Order No. 7803; Withdrawal of Public Lands for the Limestone Hills... laws, for a period of 5 years. This withdrawal will protect the Limestone Hills Training Area...

  2. Landing and Oviposition Responses of Rhagoletis indifferens (Dipt., Tephritidae) on Sweet Cherry Treated with Kaolin- and Limestone-Based Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Kaolin- and limestone-based products were compared for their effects on landing and oviposition on sweet cherry by Rhagoletis indifferens Curran (Dipt., Tephritidae). Surround (95% calcined kaolin), Cocoon (100% hydrous kaolin), Eclipse (>97% limestone), and Purshade (62.5% limestone) were studied....

  3. Effects of impurities on the removal of heavy metals by natural limestones in aqueous systems.

    PubMed

    Sdiri, Ali; Higashi, Teruo; Jamoussi, Fakher; Bouaziz, Samir

    2012-01-01

    Effects of impurities on the removal of heavy metals by natural limestones in aqueous solutions were studied by evaluating various factors including limestone concentration, pH, contact time and temperature. Solutions of Pb(II), Cd(II), Cu(II) and Zn(II), prepared from chloride reagents at a concentration of 10 mg/L, were studied in a batch method. Four natural limestone samples, collected from the Campanian-Maastrichtian limestone beds in Tunisia, were used as adsorbents. Sorption experiments indicated that high removal efficiencies could be achieved. Limestone samples containing impurities, such as silica, iron/aluminum oxides and different kinds of clay minerals, demonstrated enhanced sorption capacity, nearing 100% removal in some cases. Kinetic experiments showed that the sorption of metal ions occurred rapidly at a low coverage stage, and that solutions were nearly at equilibrium after 60 min. Data trends generally fit pseudo-second order kinetic, and intra-particle diffusion, models. The following conditions were found to promote optimum, or near-optimum, sorption of heavy metals: 1) contact time of more than 60 min, 2) pH = 5, 3) >3 g/L limestone concentration and 4) T = 35 °C. The results of this study suggest that the limestones from northern Tunisia, that contain higher amounts of silica and iron/aluminum oxides, are promising adsorbents for the effective removal of toxic heavy metals from wastewaters. PMID:22054591

  4. Stratigraphy and sedimentology of the Upper Cretaceous (Campanian) Anacacho Limestone, Texas, USA

    USGS Publications Warehouse

    Swezey, C.S.; Sullivan, E.C.

    2004-01-01

    The Upper Cretaceous Anacacho Limestone is exposed in outcrops between the cities of San Antonio and Del Rio, Texas. A detailed study of four outcrops (Blanco Creek section, Sabinal River section, Seco Creek section, Hondo Creek section) shows that the Anacacho Limestone rests on the Upson Clay (which contains fauna of early Campanian age) and is overlain by the Corsicana Marl (which contains fauna of early Maastrichtian age). An unconformity within the Anacacho Limestone is used herein to separate the limestone into a lower member and an upper member. The lower Anacacho member contains fauna of early Campanian age, whereas the upper Anacacho member contains fauna of middle Campanian age. The lower Anacacho member consists predominantly of wackestones to packstones, which are overlain by packstones to grainstones capped by the unconformity. This unconformity is interpreted as a marine flooding surface, delineating a transition from carbonate grainstones deposited in shallow water (<30 m depth) to a chalk deposited in deeper water. Above the unconformity, the upper Anacacho member is characterized by a chalk, overlain by wackestones and packstones. The uppermost section of the Anacacho Limestone consists of packstones and grainstones with abundant and diverse fossils. Most of the Anacacho Limestone developed in relatively shallow water (<50 m depth) leeward of a large carbonate build-up (possibly a rudistid reef) that now comprises the Anacacho Mountains. The environment, however, was open to marine water throughout deposition of the Anacacho Limestone. ?? 2004 Elsevier Ltd. All rights reserved.

  5. Preliminary microfacies analysis and cyclicity of the Wahoo Limestone, Lisburne Field, North Slope, Alaska

    SciTech Connect

    Morgan, S.K.; Watts, K.F.

    1995-05-01

    A well from the Lisburne field near Prudhoe Bay was examined in core, thin section, and on well logs for comparison with Wahoo Limestone in the Arctic National Wildlife Refuge (ANWR). Carbonate cycles (parasequences) are well developed in both areas but the greater abundance of terrigenous sediment and associated carbonate facies indicate that the study well is located in a more landward position on the Wahoo carbonate ramp, closer to a source of terrigenous sediment. This report presents the preliminary results of microfacies analyses that have been conducted on 424 of a total 1,115 thin sections from the study well. The stratigraphic nomenclature extended from ANWR (the type locality of the Wahoo Limestone) is different that the terminology previously used for the subsurface Lisburne Group near Prudhoe Bay. We distinguish informal lower and upper members within the Mississippian to Pennsylvanian Wahoo Limestone which overlies the Mississippian Alapah Limestone. Our upper Alapah corresponds to the middle Alapah of previous workers. Our lower Wahoo Limestone member corresponds to the upper Alapah of previous workers. Our upper Wahoo Limestone member corresponds to the previous Wahoo Limestone and is the major hydrocarbon reservoir at the Lisburne field, which is characterized by well-developed carbonate cycles (parasequences).

  6. An Action Research Study Investigating Children's Use of an iPad during Free Play in a Kindergarten Classroom: An Exploration of Teaching Pedagogy and Children's Learning, Social Interactions, and Digital Literacy

    ERIC Educational Resources Information Center

    Reynolds-Blankenship, Tara

    2013-01-01

    As part of human development, technology plays an important role in many children's lives. As digital technologies continue to permeate aspects of many children's everyday lives, educators are integrating digital technologies into classroom practices and, as such, have created a need to examine the ways in which children use technologies in their…

  7. ARD remediation with limestone in a CO2 pressurized reactor

    USGS Publications Warehouse

    Sibrell, Philip L.; Watten, Barnaby J.; Friedrich, Andrew E.; Vinci, Brian J.

    2000-01-01

    We evaluated a new process for remediation of acid rock drainage (ARD). The process treats ARD with intermittently fluidized beds of granular limestone maintained within a continuous flow reactor pressurized with CO2. Tests were performed over a thirty day period at the Toby Creek mine drainage treatment plant, Elk County, Pennsylvania in cooperation with the Pennsylvania Department of Environmental Protection. Equipment performance was established at operating pressures of 0, 34, 82, and 117 kPa using an ARD flow of 227 L/min. The ARD had the following characteristics: pH, 3.1; temperature, 10 °C; dissolved oxygen, 6.4 mg/L; acidity, 260 mg/L; total iron, 21 mg/L; aluminum, 22 mg/L; manganese, 7.5 mg/L; and conductivity, 1400 μS/cm. In all cases tested, processed ARD was net alkaline with mean pH and alkalinities of 6.7 and 59 mg/L at a CO2 pressure of 0 kPa, 6.6 and 158 mg/L at 34 kPa, 7.4 and 240 mg/L at 82 kPa, and 7.4 and 290 mg/L at 117 kPa. Processed ARD alkalinities were correlated to the settled bed depth (p<0.001) and CO2 pressure (p<0.001). Iron, aluminum, and manganese removal efficiencies of 96%, 99%, and 5%, respectively, were achieved with filtration following treatment. No indications of metal hydroxide precipitation or armoring of the limestone were observed. The surplus alkalinity established at 82 kPa was successful in treating an equivalent of 1136 L/min (five-fold dilution) of the combined three ARD streams entering the Toby Creek Plant. This side-stream capability provides savings in treatment unit scale as well as flexibility in treatment effect. The capability of the system to handle higher influent acidity was tested by elevating the acidity to 5000 mg/L with sulfuric acid. Net alkaline effluent was produced, indicating applicability of the process to highly acidic ARD.

  8. Rehabilitation of lands mined for limestone in the Indian desert

    USGS Publications Warehouse

    Sharma, K.D.; Kumar, S.; Gough, L.P.

    2000-01-01

    In the Indian desert, the economics of mining is second only to agriculture in importance. However, research on the rehabilitation of land disturbed by mining has only recently received serious attention. An attempt has been made to determine both the qualitative and quantitative success of rehabilitation plans used to revegetate limestone mine spoils in an area near Barna, northwest arid India. Rehabilitation success was achieved using a combination of rainwater harvesting techniques, soil amendment application approaches, plant establishment methods and the selection of appropriate germplasm material (trees, shrubs and grasses). It is expected that the resulting vegetative cover will be capable of self-perpetuation under natural conditions while at the same time meeting the land-use needs of the local people. The minespoils have adequate levels of the major nutrients (except P, Mo and Se) for proper plant and grazing animal health. Levels of organic matter are low whereas total B concentrations are exceptionally high. Also, the population of soil fungi, Azotobactor, and nitrifying bacteria is negligible. Enhanced plant growth was achieved in treated plots, compared to control plots, where spoil moisture storage was improved by 5-45 per cent. Due to the decomposition of farmyard manure and nitrogen fixation by planted leguminous plant species, the electrical conductance of treated mine spoils increased threefold, CaCO3 content decreased from 20??0 to 5??2 per cent, and organic carbon, P, K, and biological activity increased significantly. The rehabilitation protocol used at the site appears to have been successful because plant self-regeneration is occurring. The increased diversity of woody perennials resulted in 'dominance' being better shared among species and 'evenness' being increased within the plant community elements. The early to mid-successional trends are continuing for six years following initial rehabilitation. This study developed methods for the

  9. Effect of the specimen length on ultrasonic P-wave velocity in some volcanic rocks and limestones

    NASA Astrophysics Data System (ADS)

    Karaman, Kadir; Kaya, Ayberk; Kesimal, Ayhan

    2015-12-01

    Ultrasonic P-wave velocity (UPV) is commonly used in different fields such as civil, mining, geotechnical, and rock engineering. One of the significant parameters which affect the UPV of rock materials is likely to be the length of test cores although it is not mentioned in the literature. In this study, in order to explore the influence of the specimen length on the UPV, rock samples were collected from eight different locations in Turkey. The NX-sized core specimens having different length of 50, 75, 100, 125, and 150 mm were prepared. Before the analyses, rocks were divided into two groups in terms of their geological origins such as volcanic and chemical sedimentary (limestone) rocks. The UPV tests were carried out under dry and saturated conditions for each 200 core specimens. By evaluating the test results, it was shown that the length of the specimens significantly affects the UPV values. Based on the regression analyses, a method was developed to determine the threshold specimen length of studied rocks. Fluctuations in UPVdry and UPVsat values were generally observed for cores smaller than the threshold specimen length. In this study, the threshold specimen length was determined as 79 mm for volcanic rocks and 109 mm for limestones.

  10. Celestite in the Weathering Crust on Limestone Exposed to an Urban Atmosphere in Cracow (Poland)

    NASA Astrophysics Data System (ADS)

    Wilczyńska-Michalik, Wanda; Michalik, Marek

    2006-01-01

    Celestite containing very low amounts of barium occurs in weathering reaction zones developed on the Pińczów limestone exposed to the polluted atmosphere of Cracow. The mineral occurs both in limestone pore spaces filled with gypsum and in black gypsum crust. The Pińczów limestone contains ca 500 ppm strontium which was released during the reaction with atmospheric pollutants. The nucleation and growth of celestite, requiring significant concentration of components in evaporating solutions, is associated with gypsum crystallization.

  11. Desulfurization with a modified limestone formulation in an industrial CFBC boiler

    SciTech Connect

    Young Goo Park; Seung Ho Kim

    2006-02-01

    This work presents a practical result of experimental investigation of the limestone particle size effect on de-SOx from a circulating fluidized bed combustion (CFBC) boiler that burns domestic anthracite and is the first industrial scale in Korea. Because of combustion problems such as clinker formation, fine limestone has not been used as a desulfurization agent. The present test, however, showed that higher content (up to 50%) of the particles under 0.1 mm did not entail any malfunction in a modern CFBC system. In addition, the desulfurization efficiency was found to be comparable to the old mode of limestone sorbents. 17 refs., 4 figs., 3 tabs.

  12. Microtaphofacies of Lower Jurassic Limestones from the Rotzo Formation, Northern Italy

    NASA Astrophysics Data System (ADS)

    Hoffmann, Luise; Nebelsick, James; Bassi, Davide; Posenato, Renato

    2015-04-01

    Microtaphofacies investigations allow for the study of taphonomic features of cemented limestones as found in thin sections. It allows for changes in environmental parameters to be assessed especially with respect to abrasion, fragmentation, encrustation and bioerosion of biotic components. Variations of taphonomic features along environmental gradients can thus be examined and can be compared to other facies determining features such as the distribution of specific biotic components as well as carbonate fabrics. The Lower Jurassic Rotzo Formation, occurring in the palaeogeographic unit Trento Platform (Southern Alps, Italy), is characterized by very well preserved components in a shallow water lagoonal setting. Components are dominated by dasycladalean algae, small and large benthic foraminifera, various bivalves, gastropods, brachiopods and echinoderms. Oncoids and trace fossils can also be prevalent. Although bioclastic components are commonly preserved in very fine micritic limestones, various types of mass occurrences are also present especially with respect to the bivalves including the well known Lithiotis fauna. Microfacies are dominated by mudstones. Bioclastic rich microfacies are also present with packstones and rudstones mainly containing foraminifera and bivalves, but also including, and in part dominated by other components. Microtaphofacies were studied along the Monte Toraro section to the east of Tonezza del Cimone (Vicenza Province). Abrasion, fragmentation, bioerosion and encrustation were qualitatively and semi-quantitatively analyzed with features being scored into three categories equivalent to good, fair, and poor preservation. This allowed for changes along the section to be analyzed. Abrasion and fragmentation are common in all facies and affect most components. Encrustation and bioerosion rates, however, are highly variably are only dominate in oncoids rich facies. Components in mass shell accumulations are often very well preserved

  13. Streptomyces canchipurensis sp. nov., isolated from a limestone habitat.

    PubMed

    Li, Wen-Jun; Nimaichand, Salam; Jiang, Zhao; Liu, Min-Jiao; Khieu, Thi-Nhan; Kim, Chang-Jin; Hozzein, Wael N; Park, Dong-Jin; Wadaan, Mohammed A M; Ningthoujam, Debananda S

    2014-12-01

    Hundung Limestone habitat, Manipur, India is an unexplored site for microbial diversity studies. Using polyphasic taxonomy, a Streptomyces strain, MBRL 172(T), has been characterized. The strain was found to show highest 16S rRNA gene sequence similarity with Streptomyces coeruleofuscus NBRC 12757(T) (99.2 %). The DNA relatedness between MBRL 172(T) and S. coeruleofuscus NBRC 12757(T), and between MBRL 172(T) and Streptomyces nogalater NBRC 13445(T), were 36.8 ± 4.4 and 52.5 ± 2.7 %, respectively. Strain MBRL 172(T) was found to contain LL-diaminopimelic acid as the diagnostic diamino acid and glucose, mannose and xylose as the major sugars in whole cell hydrolysates. The polar lipids in the cell membrane were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositolmannoside. The predominant menaquinones detected were MK-9(H6) and MK-9(H8). The cellular fatty acids identified were mainly saturated fatty acids: anteiso-C15:0, iso-C16:0 and iso-C15:0. Based on differences in the biochemical and molecular characteristics from its closest relatives, the strain can be proposed to represent a novel taxon in the genus Streptomyces, for which the name Streptomyces canchipurensis is proposed, with the type strain MBRL 172(T) (=JCM 17575(T) = KCTC 29105(T)).

  14. The Surface of a Limestone-Rich World?

    NASA Astrophysics Data System (ADS)

    Melis, Carl; Dufour, Patrick

    2016-06-01

    We present spectroscopic observations of the dust- and gas-enshrouded, polluted white dwarf star SDSSJ104341.53+085558.2 (hereafter SDSSJ1043). Hubble Space Telescope Cosmic Origins Spectrograph far-ultraviolet spectra combined with deep Keck HIRES optical spectroscopy reveal the elements C, O, Mg, Al, Si, P, S, Ca, Fe, and Ni and enable useful limits for Sc, Ti, V, Cr, and Mn in the photosphere of SDSSJ1043. From this suite of elements we determine that the parent body being accreted by SDSSJ1043 is dry, rocky, and iron-poor. Synthesizing all available heavily-polluted white dwarf measurements, we find a trend in the Fe/Mg vs Fe/Si abundance ratio-space suggestive of whether accreted material originates from the inner or outer regions of a rocky body; we use this trend to identify the material being accreted by SDSSJ1043 as likely to have come from the outermost layers of a differentiated object. Enhanced levels of Ca and C in this object can be explained by the presence of significant amounts of calcium-carbonate and, if definitive, could be suggestive of a world with a crust rich in limestone.

  15. Multispectral analysis of limestone, dolomite, and granite, Mill Creek, Oklahoma

    NASA Technical Reports Server (NTRS)

    Rowan, L. C.; Watson, K.

    1970-01-01

    Spectral reflectance and thermal emission data were collected at the Mill Creek, Oklahoma test site during NASA missions 132 and 133 in June 1970. The data were collected by three aircraft flown several times during the diurnal cycle at altitudes of 150 to 17,000 m above mean terrain. Reflectance of the main rock types (limestone, dolomite, and granite) was determined from the data collected using a 12-channel multispectral scanner during mission 133 and from thermal infrared images recorded during mission 132 on an RS-7 scanner from 17,000 m above terrain. A preliminary rock recognition map was generated automatically using data collected from 900 m above terrain. The discrimination provided by the map is reasonably accurate. Misidentification occurred in areas of unusually high dolomite reflectivity. High altitude thermal infrared (10 to 12 micrometers) images show regional folds and faults distinguished by the presence of thermally contrasting materials. Linear and curvilinear structural features two to three times smaller than the nominal 17 m resolution could be detected.

  16. Transport studies of radon in limestone underlying houses

    SciTech Connect

    Gammage, R.B.; Dudney, C.S.; Wilson, D.L.; Saultz, R.J.

    1990-01-01

    In hilly limestone terrains of the southern Appalachians, subterranean networks of solution cavities and fissures present circulatory systems facilitating convective and advective transport of radon-bearing gas. Evidence suggests that the primary driving forces for transport are aerostatic pressure differentials created by the difference between the underground and the outside air temperatures. Examples are presented of houses experiencing elevated indoor radon levels as a consequence of communicating with such subsurface transportation systems. The location of a house near the upper or lower end of a subterranean-circulatory system seems to produce amplification of indoor radon levels in winter or summer, respectively. The transport mechanism for radon-bearing air in karst and its impact on indoor radon need better understanding, both in regard to evaluating the geographical prevalence of the phenomenon and the induced spatial and temporal effects that are possible. This paper reports field studies made at houses in karst regions at Oak Ridge, Tennessee, and Huntsville, Alabama. A primary radon-transport mechanism is advocated of ascending or descending subsurface columns of air whose flows are largely driven by aerostatic pressure gradients created by the inground-outdoor air temperature differentials. 5 refs., 5 figs., 1 tab.

  17. Acid neutralization within limestone sand reactors receiving coal mine drainage

    USGS Publications Warehouse

    Watten, B.J.; Sibrell, P.L.; Schwartz, M.F.

    2005-01-01

    Pulsed bed treatment of acid mine drainage (AMD) uses CO2 to accelerate limestone dissolution and intermittent fluidization to abrade and carry away metal hydrolysis products. Tests conducted with a prototype of 60 L/min capacity showed effective removal of H+ acidity over the range 196-584 mg/L (CaCO3) while concurrently generating surplus acid neutralization capacity. Effluent alkalinity (mg/L CaCO3) rose with increases in CO2 (DC, mg/L) according to the model Alkalinity = 31.22 + 2.97(DC)0.5, where DC was varied from 11-726 mg/L. Altering fluidization and contraction periods from 30 s/30 s to 10 s/50 s did not influence alkalinity but did increase energy dissipation and bed expansion ratios. Field trials with three AMD sources demonstrated the process is capable of raising AMD pH above that required for hydrolysis and precipitation of Fe3+ and Al3+ but not Fe2+ and Mn2+. Numerical modeling showed CO2 requirements are reduced as AMD acidity increases and when DC is recycled from system effluent. ?? 2005 Elsevier Ltd. All rights reserved.

  18. Fluid distribution effect on sonic attenuation in partially saturated limestones

    SciTech Connect

    Cadoret, T.; Mavko, G.; Zinszner, B.

    1998-01-01

    Extensional and torsional wave-attenuation measurements are obtained at a sonic frequency around 1 kHz on partially saturated limestones using large resonant bars, 1 m long. To study the influence of the fluid distribution, the authors use two different saturation methods: drying and depressurization. When water saturation (S{sub w}) is higher than 70%, the extensional wave attenuation is found to depend on whether the resonant bar is jacketed. This can be interpreted as the Biot-Gardner-White effect. The experimental results obtained on jacketed samples show that, during a drying experiment, extensional wave attenuation is influenced strongly by the fluid content when S{sub w} is between approximately 70% and 100%. This sensitivity to fluid saturation vanishes when saturation is obtained through depressurization. Using a computer-assisted tomographic (CT) scan, the authors found that, during depressurization, the fluid distribution is homogeneous at the millimetric scale at all saturations. In contrast, during drying, heterogeneous saturation was observed at high water-saturation levels. Thus, the authors interpret the dependence of the extensional wave attenuation upon the saturation method as principally caused by a fluid distribution effect. Torsional attenuation shows no sensitivity to fluid saturation for S{sub w} between 5% and 100%.

  19. Colour changes by laser irradiation of reddish building limestones

    NASA Astrophysics Data System (ADS)

    Grossi, C. M.; Benavente, D.

    2016-10-01

    We have used X-ray photoelectron spectroscopy (XPS) as a novel method to investigate the causes of colour changes in a reddish limestone under irradiation by a Q-switched Nd:YAG 1064 nm laser. We irradiated clean dry and wet surfaces of Pidramuelle Roja, a building stone frequently used in the Asturian heritage, at fluences ranging from 0.12 to 1.47 J cm-2. We measured the colour coordinates and undertook XPS analysis of the state of oxidation of iron both before and after irradiation. Visible colour changes and potential aesthetic damage occurred on dry surfaces from a fluence of 0.31 J cm-2, with the stone showing a greening effect and very intense darkening. The colour change on dry surfaces was considerably higher than on wet surfaces, which at the highest fluence (1.47 J cm-2) was also above the human visual detection threshold. The use of XPS demonstrated that the change in colour (chroma and hue) is associated with a reduction in the iron oxidation state on dry surfaces during laser irradiation. This points out to a potential routinary use of XPS to analyse causes of colour changes during laser cleaning in other types of coloured building stones.

  20. The Elements of Play: Toward a Philosophy and a Definition of Play

    ERIC Educational Resources Information Center

    Eberle, Scott G.

    2014-01-01

    Scholars conventionally find play difficult to define because the concept is complex and ambiguous. The author proffers a definition of play that takes into consideration its dynamic character, posits six basic elements of play (anticipation, surprise, pleasure, understanding, strength, and poise), and explores some of their emotional, physical,…

  1. Pigs, Planes, and Play-Doh: Children's Perspectives on Play as Revealed through Their Drawings

    ERIC Educational Resources Information Center

    Duncan, Pauline Agnieszka

    2015-01-01

    Play, an elusive concept despite the extensive literature on the subject, remains especially problematic for research focused on the perspective of children. The author discusses her study on children's perspectives about play, exploring drawing as a method for learning how young children conceptualize play within a social-semiotic framework. Her…

  2. A Review of Play and Its Relationship to Learning.

    ERIC Educational Resources Information Center

    Naumburg, Janet

    The value and function of play behavior in young children, and the process and conditions by which play contributes to learning, cognition and problem solving, are explored in this literature review. The first section examines early theories of play, the psychoanalytic theory of play, and the developmental stages of play. Common elements of play…

  3. Fracture propagation and fluid transport in palaeogeothermal fields and man-made reservoirs in limestone

    NASA Astrophysics Data System (ADS)

    Philipp, S. L.; Reyer, D.; Meier, S.

    2009-04-01

    particularly on the current local stress field. One reason for this is that fractures are sensitive to changes in the stress field and deform much more easily than circular pores. If the maximum horizontal compression is oriented perpendicular to the fault strike, its fractures (mainly in the damage zone) tend to be closed and lead less water than if the maximum horizontal compression is oriented parallel to the fault strike, in which case its fractures tend to open up and be favourable to fluid transport. In areas of potential geothermal reservoirs, fault zones must be studied, keeping in mind that the permeability structure of a fault zone depends partly on the mechanical units of the fault zone and partly on the local stress field. To explore stress fields affecting fracture propagation we have run numerical models using the finite-element and the boundary-element methods. We focus on the influence of changes in mechanical properties (particularly Young's modulus) between host rock layers in geothrmal reservoirs in limestone. The numerical models show that stresses commonly concentrate in stiff layers. Also, at the contacts between soft marl and stiffer limestone layers, the stress trajectories (directions of the principal stresses) may become rotated. Depending on the external loading conditions, certain layers may become stress barriers to fracture propagation. In a reservoir where most hydrofractures become stratabound (confined to individual layers), interconnected fracture systems are less likely to develop than in one with non-stratabound hydrofractures. Reservoirs with stratabound fractures may not reach the percolation threshold needed for significant permeability. We also used the field data to investigate the fracture-related permeability of fluid reservoirs in limestone with numerical models. We simulated different scenarios, in which potential fluid pathways were added successively (vertical extension fractures, inclined shear fractures and open layer contacts

  4. Play Therapy with Emotionally Damaged Adolescents.

    ERIC Educational Resources Information Center

    Wilson, Kate; Ryan, Virginia

    2002-01-01

    This article argues that non-directive play therapy offers an approach that is well suited to addressing adolescent concerns. The argument is illustrated by two accounts of therapy that show how a more traditional non-directive counseling approach was combined with play therapy by the adolescents themselves, allowing exploration of emotional…

  5. Metamorphosis: Play, Spirituality and the Animal

    ERIC Educational Resources Information Center

    Bone, Jane

    2010-01-01

    Animal- and bird-becoming is an aspect of play as metamorphosis connected to spirituality in early childhood settings. The reconceptualisation of play presented here is supported by research that explored the spiritual experiences of young children in different early childhood contexts. Qualitative case study research carried out in Aotearoa New…

  6. Preschool Children's Outdoor Play Area Preferences

    ERIC Educational Resources Information Center

    Holmes, Robyn M.; Procaccino, Jill K.

    2009-01-01

    This study explores preschool children's outdoor play preferences. The sample was 40 (20 male, 20 female) primarily European-American three and four year olds. Data were collected via naturalistic observation and analyzed using repeated measures ANOVAs and MANOVAs. The independent variable was sex of child; dependent variable was play space…

  7. New Directions in Play: Consensus or Collision?

    ERIC Educational Resources Information Center

    Wood, Elizabeth

    2007-01-01

    The aims of this article are to explore contemporary challenges to developing play in early childhood settings, and to identify areas of consensus and collision in policy and practice. Contemporary research highlights the effectiveness of mixed pedagogical approaches, including child- and adult-initiated play. Whilst early childhood specialists…

  8. Drawings as Spaces for Intellectual Play

    ERIC Educational Resources Information Center

    Wood, Elizabeth; Hall, Emese

    2011-01-01

    The aims of this article are to explore the links between drawing and playing and to conceptualise drawings as spaces for intellectual play. The empirical research that supports this position is based on an interpretivist study involving 14 children aged four-six in a primary school in England. Over a one-year period, 882 drawings were collected…

  9. Neutron radiography and X-ray computed tomography for quantifying weathering and water uptake processes inside porous limestone used as building material

    SciTech Connect

    Dewanckele, J.; De Kock, T.; Fronteau, G.; Derluyn, H.; Vontobel, P.; Dierick, M.; Van Hoorebeke, L.; Jacobs, P.; Cnudde, V.

    2014-02-15

    Euville and Savonnières limestones were weathered by acid test and this resulted in the formation of a gypsum crust. In order to characterize the crystallization pattern and the evolution of the pore structure below the crust, a combination of high resolution X-ray computed tomography and SEM–EDS was used. A time lapse sequence of the changing pore structure in both stones was obtained and afterwards quantified by using image analysis. The difference in weathering of both stones by the same process could be explained by the underlying microstructure and texture. Because water and moisture play a crucial role in the weathering processes, water uptake in weathered and non-weathered samples was characterized based on neutron radiography. In this way the water uptake was both visualized and quantified in function of the height of the sample and in function of time. In general, the formation of a gypsum crust on limestone slows down the initial water uptake in the materials. - Highlights: • Time lapse sequence in 3D of changing pore structures inside limestone • A combination of X-ray CT, SEM and neutron radiography was used. • Quantification of water content in function of time, height and weathering • Characterization of weathering processes due to gypsum crystallization.

  10. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States

    SciTech Connect

    Youngdahl, C.A.

    1987-08-01

    Weight losses of marble and limestone samples exposed to outdoor environments at field sites in the eastern United States have been monitored in studies initiated in 1984. The prodcedures are described, and the results are tabulated and discussed. A rate of marble loss approximately equivalent to 16 ..mu..m of surface recession per year was found in North Carolina, and losses of this order were also observed in New Jersey, New York, and Washington, DC. Limestone weight losses were much higher than for marble in the first year; loss of extraneous materials from the porous limestone appeared to be a likely contributor to the overall loss. The rate of limestone loss diminished in the second year, though it continued to be higher than for marble. Exposures are continuing in a planned 10-yr program of tests. 8 refs., 3 figs., 5 tabs.

  11. Studies on the reaction of calcined limestone with sulfur dioxide: Topical report, October 1985-September 1986

    SciTech Connect

    Sotirchos, S.V.

    1986-10-01

    The primary objective of this project, which constitutes a balanced program of theoretical and experimental work, is the development of a systematic procedure for the description of the sorptive capacity for SO/sub 2/ removal of a given limestone or dolomite starting from basic physical principles and experimental information. Our research chiefly focusses on the experimental and theoretical investigation of the effects of the initial pore structure of limestone or dolomite and of its evolution with the progress of the reaction on the transient behavior of calcined limestone or dolomite particles reacting in an environment of SO/sub 2/ and O/sub 2/. Particular attention is paid to the effects of the intraparticle mass transport process on the sorpting capacity of reacting limestone particles.

  12. Hydration study of limestone blended cement in the presence of hazardous wastes containing Cr(VI)

    SciTech Connect

    Trezza, M.A.; Ferraiuelo, M.F

    2003-07-01

    Considering the increasing use of limestone cement manufacture, the present paper tends to characterize limestone behavior in the presence of Cr(VI). The research reported herein provides information regarding the effect of Cr(VI) from industrial wastes in the limestone cement hydration. The cementitious materials were ordinary Portland cement, as reference, and limestone blended cement. The hydration and physicomechanical properties of cementitious materials and the influence of chromium at an early age were studied with X-ray diffraction (XRD), infrared spectroscopy (FTIR), conductimetric and mechanical tests. Portland cement pastes with the addition of Cr(VI) were examined and leaching behavior with respect to water and acid solution were investigated. This study indicates that Cr(VI) modifies the rate and the components obtained during the cement hydration.

  13. Primary deforestation and regrowth on limestone slopes on Vancouver Island, British Columbia

    SciTech Connect

    Harding, K.A.; Ford, D.C. . Dept. of Geography)

    1992-01-01

    Limestones, well bedded and steeply dipping, are common in northern Vancouver Island. They have been glaciated and host a high density of postglacial karren (dissolution pits, grooves and troughs linked to underlying caves). There is rich, mature forest cover of western hemlock, silver fir and red cedar that is rooted in the karren or in overlying glacial deposits. Logging commenced around 1900 AD, intensifying after 1960 with clear cutting and (often) burning of slash. Impacts were investigated quantitatively by comparing sixteen limestone sites with eight on adjoining volcanic rocks. Some sites on each retained original forest, other were cleared. It was found that soil losses following logging are significantly greater on the limestones because of wash into karren (the epikarst zone). Regrowth is retarded on the limestones also; one site cleared in 1911 had regained approximately 17% of its original volume of timber 75 years later.

  14. Play and Digital Media

    ERIC Educational Resources Information Center

    Johnson, James E.; Christie, James F.

    2009-01-01

    This article examines how play is affected by computers and digital toys. Research indicates that when computer software targeted at children is problem-solving oriented and open-ended, children tend to engage in creative play and interact with peers in a positive manner. On the other hand, drill-and-practice programs can be quite boring and limit…

  15. Play as Experience

    ERIC Educational Resources Information Center

    Henricks, Thomas S.

    2015-01-01

    The author investigates what he believes one of the more important aspects of play--the experience it generates in its participants. He considers the quality of this experience in relation to five ways of viewing play--as action, interaction, activity, disposition, and within a context. He treats broadly the different forms of affect, including…

  16. Play, Toys and Television.

    ERIC Educational Resources Information Center

    Brougere, Gilles

    In Western societies, television has transformed the life, culture, and points of reference of the child. Its particular sphere of influence is the child's play culture. This play culture is not hermetic: it is very oriented toward manipulation; has a symbolic role as a representational medium; evolves along with the child; has a certain amount of…

  17. An Invitation to Play.

    ERIC Educational Resources Information Center

    Lange, Jenny; Zieher, Connie

    The manual is intended to provide suggestions for play to parents of young children with exceptional educational needs. Nineteen types of activities are described and pictured, including make believe with boxes, dress-up activities, kitchen play, bubbles, small motor activities using beans and buttons, use of throw-away materials, painting,…

  18. Let's Just Play

    ERIC Educational Resources Information Center

    Schmidt, Janet

    2003-01-01

    Children have a right to play. The idea is so simple it seems self-evident. But a stroll through any toy superstore, or any half-hour of so-called "children's" programming on commercial TV, makes it clear that violence, not play, dominates what's being sold. In this article, the author discusses how teachers and parents share the responsibility in…

  19. Television at Play.

    ERIC Educational Resources Information Center

    Reid, Leonard N.; Frazer, Charles F.

    1980-01-01

    Discusses children as television viewers capable of manipulating the co-viewing setting by interpreting, constructing, and carrying out planned lines of play in relation to television and its content. Examples illustrate program-oriented and free-form improvisational play situations. (JMF)

  20. Return to Play

    ERIC Educational Resources Information Center

    Mangan, Marianne

    2013-01-01

    Call it physical activity, call it games, or call it play. Whatever its name, it's a place we all need to return to. In the physical education, recreation, and dance professions, we need to redesign programs to address the need for and want of play that is inherent in all of us.

  1. The Fear of Play

    ERIC Educational Resources Information Center

    Almon, Joan

    2009-01-01

    Real play--play that is initiated and directed by children and that bubbles up from within the child rather than being imposed by adults--has largely disappeared from the landscape of childhood in the United States. There are many reasons for this, such as the long hours spent in front of screens each day or in activities organized by adults. In…

  2. Theories of Play.

    ERIC Educational Resources Information Center

    Peller, Lili E.

    1996-01-01

    Discusses several theories of play advanced before the development of psychoanalysis, including the theories of surplus energy, recreation, and practice. Examines the psychoanalytical view advanced by Freud and others, which focuses on the emotional release of play and its role in discovery and learning. (MDM)

  3. Why People Play.

    ERIC Educational Resources Information Center

    Ellis, M. J.

    A critical analysis is made of the content and assumptions of the many theories or explanations for play behavior. The seven chapters of the book are as follows. Chapter One, A Purview of the Problems, is a brief overview of the problems inherent in attempting to manage play, and the arguments for and against. The second chapter, Definitions of…

  4. Poetry and Play.

    ERIC Educational Resources Information Center

    Law, Richard A.

    Philosophers and poets from classical times to the present have argued that playful and amiable discourse are conducive to teaching and learning. The play principle enhances reading and study and should be applied by teachers to benefit their students. Teachers should help their students see that it is fun to enliven the imagination with good…

  5. Clinical Intuition at Play

    ERIC Educational Resources Information Center

    Marks-Tarlow, Terry

    2014-01-01

    A clinical psychologist and consulting psychotherapist discusses how elements of play, inherent in the intuition required in analysis, can provide a cornerstone for serious therapeutic work. She argues that many aspects of play--its key roles in human development, individual growth, and personal creativity, among others--can help therapists and…

  6. Intergenerational Learning through Play.

    ERIC Educational Resources Information Center

    Davis, Lindsay; Larkin, Elizabeth; Graves, Stephen B.

    2002-01-01

    Argues that shared play experiences are a good way to build mutually beneficial relationships among older and younger generations. Outlines why intergenerational play is important, focusing on its cognitive, social, physical, and emotional benefits for both older adults and young children. Describes toys, materials, and games conducive to positive…

  7. Family Play Therapy.

    ERIC Educational Resources Information Center

    Ariel, Shlomo

    This paper examines a case study of family play therapy in Israel. The unique contributions of play therapy are evaluated including the therapy's accessibility to young children, its richness and flexibility, its exposure of covert patterns, its wealth of therapeutic means, and its therapeutic economy. The systematization of the therapy attempts…

  8. The minimal response to contact metamorphism by the Devonian Buchan Caves Limestone, Buchan Rift, Victoria, Australia

    USGS Publications Warehouse

    Barker, C.E.; Bone, Y.

    1995-01-01

    A 2.2 m thick, Late Eocene (?) dike that intruded the Devonian Buchan Caves Limestone, near Murrindal, Victoria, has produced a narrow contact aureole only centimeters wide in the adjacent host rock. The lack of response of the Buchan Caves Limestone to contact metamorphism is attributed to: 1) prior heating to near 200??C; and 2) the fact that the dike intruded into cool, near surface, low-porosity rocks which may have been in the vadose zone. -from Authors

  9. Size and performance of anoxic limestone drains to neutralize acdic mine drainagei

    USGS Publications Warehouse

    Cravotta, C.A.

    2003-01-01

    Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict the alkalinity produced within an ALD and to estimate the mass of limestone required for its construction on the basis of data from short-term, closed-container (cubitainer) tests. The cubitainer tests, which used an initial mass of 4 kg crushed limestone completely inundated with 2.8 L AMD, were conducted for 11 to 16 d and provided estimates for the initial and maximum alkalinities and corresponding rates of alkalinity production and limestone dissolution. Long-term (5-11 yr) data for alkalinity and CaCO3 flux at the Howe Bridge, Morrison, and Buck Mountain ALDs in Pennsylvania, USA, indicate that rates of alkalinity production and limestone dissolution under field conditions were comparable with those in cubitainers filled with limestone and AMD from each site. The alkalinity of effluent and intermediate samples along the flow path through the ALDs and long-term trends in the residual mass of limestone and the effluent alkalinity were estimated as a function of the computed detention time within the ALD and second-order dissolution rate models for cubitainer tests. Thus, cubitainer tests can be a useful tool for designing ALDs and predicting their performance.

  10. An Unusual Process of Accelerated Weathering of a Marly Limestone

    NASA Astrophysics Data System (ADS)

    Ercoli, L.; Rizzo, G.; Algozzini, G.

    2003-04-01

    This work deals with a singular case of stone deterioration, which occurred during the restoration of the Cathedral of Cefalù. In particular, a significant process of stone decohesion started after a consolidation treatment on ashlars of the external face of the cloister portico. A study was carried out to characterize the stone and to investigate the deterioration process. Petrographical, chemical and physical analyses were performed on samples taken from the wall. The results indicate that the medieval monument was built using a Pliocene marly limestone, called "trubo", quarried from outcrops of the environs of Cefalù. The rock is soft and uniformely cemented. The carbonatic fraction of the rock is due to foraminifera shells; the rock also contains detritic quartz, feldspate and glauconite. The clay minerals, mainly illite and montmorillonite, are widespread in the rock in the form of thin layers. The use of such a stone in a building of relevant artistic value is definitely unusual. In fact, the "trubo" is a rock subjected to natural decay because of its mineralogical composition and fabric; as effect of natural weathering, in the outcrops the rock disaggregates uniformely, producing silt. In the cloister this effect was magnified by extreme environmental conditions (marine spray, severe excursions of both relative humidity and temperature). Furthermore, after soluble salts removing and subsequent consolidation with ethyl silicate, a significant acceleration of the decay process was observed, producing friable scales detach for a depth of about 3 cm into the ashlars. The stone appeared corroded and uneven. Experimental tests were performed in laboratory in order to evidence any origin of incompatibility between such stone composition and the treatments carried out, which on the other hand are the most generally adopted in restoration interventions.

  11. Techniques to improve the economics of limestone FGDS

    SciTech Connect

    Bresowar, G.E.; Klingspor, J.

    1995-12-31

    Many utilities have evaluated the cost of scrubbing versus fuel switching in various plans and scenarios to determine the most economical means for meeting the requirements of the new law. Presently, the future cost of removing a ton of SO{sub 2} is based on fuel switching, and the market values are in the range of $150 - $250 per ton. The perceived cost of FGDS retrofits is $250 - $400 per ton for eastern medium to high sulfur coal. ABB has studied the overall costs of FGDS and has developed a series of cost reducing improvements. and innovations. The improvements are manifested in ABBs new limestone FGDS technology known by the code phrase {open_quote}Stealth FGDS{close_quotes}. Stealth promises low capital and operating cost, high removal efficiencies for SO{sub 2} and other pollutants, little or positive environmental and economic impact on the local community, salable or non-hazardous by-products, ease of retrofit, and exceptionally short installation schedules. The concepts are being demonstrated in one system at the Miles Generating Station of Ohio Edison Company. Bearing the name {open_quote}LS-2 Advanced SO, Scrubbing{close_quotes}, the Stealth scrubber at Niles is a 110 MWe turnkey, retrofit unit to be completed 20 months after the release of engineering. It will remove 20,000 or more tons per year of SO{sub 2} from the flue gases generated by both Unit 1 and Unit 2 boilers, producing wallboard-grade gypsum. Upon completion of a four month test program, the plant will be operated by Ohio Edison for a four to five year reliability demonstration period. The performance and economic projections for LS-2 scrubbers show the technology to be quite attractive relative to projections for fuel switching when installed in a manner similar to the installation plan for Niles. The description and basis for these economic projections are described in this paper.

  12. Mangrove plantation over a limestone reef - Good for the ecology?

    NASA Astrophysics Data System (ADS)

    Asaeda, Takashi; Barnuevo, Abner; Sanjaya, Kelum; Fortes, Miguel D.; Kanesaka, Yoshikazu; Wolanski, Eric

    2016-05-01

    There have been efforts to restore degraded tropical and subtropical mangrove forests. While there have been many failures, there have been some successes but these were seldom evaluated to test to what level the created mangrove wetlands reproduce the characteristics of the natural ecosystem and thus what ecosystem services they can deliver. We provide such a detailed assessment for the case of Olango and Banacon Islands in the Philippines where the forest was created over a limestone reef where mangroves did not exist in one island but they covered most of the other island before deforestation in the 1940s and 1950s. The created forest appears to have reached a steady state after 60 years. As is typical of mangrove rehabilitation efforts worldwide, planting was limited to a single Rhizophora species. While a forest has been created, it does not mimic a natural forest. There is a large difference between the natural and planted forests in terms of forest structure and species diversity, and tree density. The high density of planted trees excludes importing other species from nearby natural forests; therefore the planted forest remains mono-specific even after several decades and shows no sign of mimicking the characteristics of a natural forest. The planted forests provided mangrove propagules that invaded nearby natural forests. The planted forest has also changed the substratum from sandy to muddy. The outline of the crown of the planted forest has become smooth and horizontal, contrary to that of a natural forest, and this changes the local landscape. Thus we recommend that future mangrove restoration schemes should modify their methodology in order to plant several species, maintain sufficient space between trees for growth, include the naturally dominant species, and create tidal creeks, in order to reproduce in the rehabilitated areas some of the key ecosystem characteristics of natural mangrove forests.

  13. Accelerated weathering of limestone for CO2 mitigation opportunities for the stone and cement industries

    USGS Publications Warehouse

    Langer, W.H.; Juan, C.A.S.; Rau, G.H.; Caldeira, K.

    2009-01-01

    Large amounts of limestone fines coproduced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO 2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point-sources such as cement manufacturing. AWL reactants are readily available, inexpensive, and environmentally benign. Waste CO 2 is hydrated with water to produce carbonic acid, which then reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities within about 10 km of the coastline. The majority of U.S. coastal power generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufactures, and research scientists.

  14. Novel preparation method of macroporous lime from limestone for high-temperature desulfurization

    SciTech Connect

    Sasaoka, Eiji; Uddin, M.A.; Nojima, Shigeru

    1997-09-01

    Limestone is a very important material as a high temperature desulfurization sorbent: limestone is used for in-bed SO{sub 2} capture in fluidized bed combustors of coal and can be used in coal gasifiers for the in-bed removal of H{sub 2}S. In order to develop a highly active calcium oxide high-temperature desulfurization sorbent, macroporous calcium oxides were directly prepared from limestone. This method is composed of two steps: swelling of the limestone in the gas phase followed by drying and calcination of the swelled samples. The swelling was found when limestone was exposed to a vapor of aqueous acetic acid. The swelling of the sample resulted from an increase of calcium acetate formation in the sample. It was then converted to macroporous calcium oxides by heating the sample to 850 C. The reactivity of the macroporous calcium oxide for the removal of SO{sub 2} or H{sub 2}S under coexisting H{sub 2}O vapor was higher than that of the calcined raw limestone. In particular, its SO{sub 2} removal capacity and oxidative character of CaS to CaSO{sub 4} and CaO were greatly improved by the swelling method.

  15. A model for prediction of limestone dissolution in wet flue gas desulfurization applications

    SciTech Connect

    Brogren, C.; Karlsson, H.T.

    1997-09-01

    A model has been developed to predict the dissolution rate of a limestone slurry as a function of particle size distribution and limestone conversion. The model is based on basic mass-transfer theory and includes a factor allowing the flux of calcium ions from the limestone surface to vary with the fraction dissolved. Changes in the flux with the fraction dissolved have been reported to be caused by the presence of sulfite but can also be caused by accumulation of inerts at the liquid-solid interface and/or by changes in the effective mass-transfer area. Calculations show that the decrease in flux reported for sulfites can have a significant impact on the slurry conditions within the reaction tank, i.e., impact on the limestone conversion and the relationship between liquid and solid alkalinity. In the absence of sulfites, the flux from limestone particles has been assumed to be constant with respect to the degree of dissolution. The modeling results have been found to be in good agreement with the measured values of a continuous stirred tank reactor. The model was able to accurately predict the impact of both the particle size distribution and reaction tank residence time on limestone conversion and dissolution rate.

  16. Model for the sulfidation of calcined limestone and its use in reactor models

    SciTech Connect

    Heesink, A.B.M.; Brilman, D.W.F.; Swaaij, W.P.M. van

    1998-07-01

    Limestone, both in raw and in calcined form, can be used to remove H{sub 2}S from coal gas. A mathematical model describing the sulfidation of a single calcined limestone particle was developed and experimentally verified. This model, which includes no fitting parameters, assumes a calcined limestone particle to consist of spherical grains of various sizes that react with H{sub 2}S according to the elastic shrinking-core model. The initial size distribution of the grains is derived from mercury porosimetry. The transport of H{sub 2}S through the bidisperse limestone particle is calculated based on the random-pore model of Wakao and Smith, which distinguishes macropore and micropore zones. Knudsen diffusivity inside the micropore zones is calculated according to the dusty-gas approach. The single-particle model delivers the value of a new defined utilization factor, which includes effects of external mass-transfer limitation, pore-diffusion limitation, and grain-size distribution on particle reactivity. A correlation derived for a single batch of calcined limestone explicitly expresses this utilization factor as a function of conversion and relevant process parameters. This correlation can be easily incorporated into reactor models, as shown for an existing model describing the capture of H{sub 2}S by a fluidized bed of calcined limestone particles.

  17. Sedimentology and diagenesis of Miocene Lirio Limestone, Isla de Mona, Puerto Rico

    SciTech Connect

    Ruiz, H.; Gonzalez, L.A.; Budd, A.F. )

    1991-03-01

    Isla de Mona is a carbonate plateau, 50 mi west of Puerto Rico. The island lies on the southern portion of the Mona Platform. It is composed mostly of two Miocene carbonate units: Isla de Mona Dolomite overlain by Lirio Limestone. The Lirio Limestone was deposited on a sloping erosional surface over the Isla de Mona Dolomite. The Miocene Lirio Limestone consists mostly of backreef sands (packstones) with a reefal sequence (boundstones and grainstones) present in the southwestern portion of the island. The reefal sequence is made up mostly of Stylophora, Porites, and Millepora. Thin, discreet pockets of carbonate mud, rich in planktonic foraminifera and radiolarians and mixed with shallow benthic fauna/flora (foraminifera, echinoderms, red algae, and corals) interpreted as storm deposits, are found throughout the unit. An extensive reefal zone can be inferred to be present throughout the southwestern to southern portions of the Mona Platform. The Lirio Limestone is heavily karstified and is riddled with sinkholes on the plateau surfaces and caves around the periphery of the island. Caves are exposed around the periphery of the island, radiating from a depression in the central portions of the Lirio Limestone, near contacts with the Isla de Mona Dolomite, are partially dolomitized. The southwestern outcrops exhibit partial dolomitization throughout. The distribution of sinkholes, seaward caverns, and partial dolomitization of the lowermost Lirio Limestone suggests diagenetic modifications by meteoric fluids in central exposed portions of the island and by marine-meteoric fluids in the lowermost portions of the phreatic lens.

  18. Interpretation of well hydrographs in the karstic Maynardville Limestone at the Oak Ridge Y-12 Plant

    SciTech Connect

    Shevenell, L.A.; McMaster, B.W.

    1996-06-01

    The Maynardville Limestone in Oak Ridge, Tennessee underlies the southern portion of Bear Creek Valley (BCV), and is considered to be the primary pathway for groundwater leaving the Y-12 Plant boundaries. Sixty-seven percent of all wells drilled into the Maynardville Limestone have intersected at least one cavity, suggesting karst features may be encountered throughout the shallow (< 200 ft) portions of the Limestone. Because waste facilities at the Y-12 Plant are located adjacent to the Maynardville Limestone, contaminants could enter the karst aquifer and be transported in the conduit system. As part of an overall hydrologic characterization effort of this karst aquifer, 41 wells in the Maynardville Limestone were instrumented with pressure transducers to monitor water level changes (hydrographs) associated with rain events. Wells at depths between approximately 20 and 750 ft were monitored over the course of at least two storms in order that variations with depth could be identified. The wells selected were not exclusively completed in cavities but were selected to include the broad range of hydrologic conditions present in the Maynardville Limestone. Cavities, fractures and diffuse flow zones were measured at a variety of depths. The water level data from the storms are used to identify areas of quickflow versus slower flowing water zones. The data are also used to estimate specific yields and continuum transmissitives in different portions of the aquifer.

  19. Direct sulfation of limestone based on oxy-fuel combustion technology

    SciTech Connect

    Chen, C.M.; Zhao, C.S.; Liu, S.T.; Wang, C.B.

    2009-10-15

    With limestone as the sorbent, the sulfation reaction can proceed via two different routes depending on whether calcination of the limestone takes place under the given reaction conditions. The direct sulfation reaction is defined as the sulfation reaction between sulfur dioxide (SO{sub 2}) and limestone in an uncalcined state. This reaction, based on oxyfuel combustion technology, was studied by thermogravimetric analysis. Surface morphologies of the limestone particles after sulfation were examined by a scanning electron microscope. Results show that there are more pores or gaps in the product layer formed by direct sulfation of limestone than by indirect sulfation, which can be attributed to the generation of carbon dioxide (CO{sub 2}) at a reaction interface. Compared with indirect sulfation, direct sulfation of limestone can yield much higher conversion and has a much higher reaction rate. For direct sulfation, the greater porosity in the product layer greatly reduces the solid-state ion diffusion distance, resulting in a higher reaction rate and higher conversion.

  20. Lower Cretaceous and Upper Jurassic oil reservoirs of the updip basement structure play: Southwest Alabama

    SciTech Connect

    Mink, R.M.; Mancini, E.A.

    1995-10-01

    Exploration for Lower Cretaceous and Upper Jurassic reservoirs associated with updip basement structures currently is the most active exploratory oil play in Alabama. High initial flow rates, on the order of hundreds to thousands of barrels of oil per day, are commonly encountered at depths between 8,200 and 14,500 feet. Fifty-one fields have been established and 25 million barrels of oil have been produced from these fields developed in Lower Cretaceous Hosston and Upper Jurassic Haynesville, Smackover, and Norphlet reservoirs. Production from Smackover carbonates began at Toxey field in 1967 and from Haynesville sandstones at Frisco City field in 1986. As of September 1994, Smackover wells averaged 88 barrels of oil per day and Haynesville wells averaged 284 barrels of oil per day. In 1994, production was established in the Norphlet at North Excel field and in the Hosston at Pleasant Home field. Reservoirs in the updip basement structure play cluster in three distinct areas; (1) a western area on the Choctaw ridge complex, (2) a central area on the Conecuh ridge complex, and (3) an eastern area in the Conecuh embayment. Reservoir lithologies include Smackover limestones and dolostones and Hosston, Haynesville, Smackover, and Norphlet sandstones. Hydrocarbon traps are structural or combination traps where reservoirs occur on the flanks or over the crests of basement palohighs. An understanding of the complex reservoir properties and trap relationships is the key to successful discovery and development of Lower Cretaceous and Upper Jurassic oil reservoirs of the updip basement structure play of southwest Alabama.

  1. Play Spaces in Denmark.

    ERIC Educational Resources Information Center

    Mitchell, Edna; Anderson, Robert T.

    1980-01-01

    Describes the variety of play spaces found in urban areas in Denmark: in banks, stores and individual businesses, neighborhood parks and small pocket playgrounds, specialized adventure and traffic playgrounds with supervised activities, and commercial amusement parks. (CM)

  2. The Scottish Play.

    ERIC Educational Resources Information Center

    Wheat, Chris

    1999-01-01

    Recounts an episode when, as young schoolboys, Prince Charles and classmates presented "Macbeth" as an end-of-term-play. Traces the events at school that took on different meanings when viewed from maturity. (NH)

  3. Nomination of the Globigerina Limestone of the Maltese Islands as a "Global Heritage Stone Resource"

    NASA Astrophysics Data System (ADS)

    Cassar, JoAnn

    2016-04-01

    The Maltese Islands consist of two main islands, Malta and Gozo, as well as a small number of islets, and lie in the central Mediterranean Sea approximately 90 km south of Sicily. Although only 316 square kilometres in size, the Islands contain a rich concentration of archaeological sites and historic buildings, as well as vernacular architecture and modern buildings, for the most part built of the local Globigerina Limestone, which is one of the few natural resources of the Islands. This stone can be described as a typical "soft limestone", very easy to carve and shape. It forms part of the large family of Oligo-Miocene "soft limestones" widely diffused in the Mediterranean Basin. The Maltese Globigerina Limestone Formation is one of five main Formations, and varies in thickness from 20 to over 200 m. The material used for building is located stratigraphically in the lower part of the Globigerina Limestone Formation, called the Lower Globigerina Limestone. This Formation is stratified into thick beds at outcrop. Sections where bioturbation is concentrated often also occur. This limestone is fine-grained, yellow to pale grey in colour, almost wholly composed of the tests of globigerinid planktonic foraminifera. Petrographically, Globigerina Limestone can be described as a bioclastic packstone, with bioclastic wackestones also occurring. This limestone has always been used as the predominant building material in the Islands. The Maltese prehistoric Temples, which were constructed approximately 6000 years ago, bear testimony to this. Between 1530 and 1798 the Order of the Knights of St John built kilometres of fortifications in this same material to protect the Island from the expanding Ottoman Empire. Fortifications, impressive churches, auberges and palaces were built of this stone during this period. The capital city of Valletta, a rich and dense manifestation of Baroque architecture in Globigerina Limestone, is included on the UNESCO World Heritage List, as are

  4. Comparative study of porous limestones used in heritage structures in Cyprus and in Hungary

    NASA Astrophysics Data System (ADS)

    Theodoridou, Magdalini; Ioannou, Ioannis; Rozgonyi-Boissinot, Nikoletta; Török, Ákos

    2015-04-01

    Porous limestone is widely used as construction material in the monuments of Cyprus and Hungary. The present study compares the physical properties of a bioclastic limestone from Cyprus and an oolitic limestone from Hungary. Petra Gerolakkou is a Pliocene limestone from Cyprus that originates from the district of Nicosia, the island's capital. It has been extensively used throughout the years in construction and restoration projects, particularly in the Nicosia area. Distinctive examples of its use can be found in the majority of the most important historic monuments in Nicosia, such as the Venetian walls and fortifications, churches (e.g. the Agia Sofia Cathedral), the archbishop and presidential palaces and a high number of other traditional buildings. The studied Miocene limestone from Hungary was exploited from Sóskút quarry (15-20 km W-SW to Budapest). The quarry provided stone for emblematic monuments of the capital of Hungary such as the Parliament building, Mathias Church, the Opera House and Citadella. In this study, mechanical parameters for both aforementioned stones, such as uniaxial compressive and tensile strengths, were tested under laboratory conditions. Their density, porosity and water absorption were also compared. The studied limestone from Cyprus exhibits porosity values within the range of 48-51%, apparent density between 1340 and 1400 kg/m3 and strength values under uniaxial compressive load between 1.2 and 2.8 MPa. This lithotype is also considered susceptible to salt decay, since an approximate mass loss of 12.5% is noted after 15 salt crystallization artificial weathering cycles. The porosity of the Hungarian limestone is in the order of 16-35%, the bulk density is 1600-1950 kg/m3, while the compressive strength is 2.5-15 MPa. Durability tests indicate that even after 10 freeze-thaw cycles the loss in strength is dramatic. Test results indicate that use of porous limestone in both countries is common and fabric strongly controls the

  5. Exploration models for Tertiary lacustrine carbonates, Liaodong Bay, People`s Republic of China

    SciTech Connect

    Lomando, A.J.

    1996-12-31

    Lacustrine carbonates are a significant reservoir target in the basins of eastern China. Difficulty in seismically imaging this play type generates the need for accurate exploration models to define geometries for lead and prospect identification. Rifted and karsted Cambro-Ordovician carbonates form the base of the section which is overlain by thick Tertiary lacustrine deposits. Two types of lacustrine carbonate plays have been identified. Carbonate alluvial fans developed from the erosion of Cambro-Ordovician dolomites and limestones in places along the flanks of tilted fault block ridges. During lake formation and expansion, these fans formed small shelves along the lake margins which became the sites of active carbonate production and winnowing. This play type forms discontinuous trends of lacustrine shoreline skeletal grainstones which mimic the underlying fan geometries. A second play type was identified in the JZ-20/JZ-9 trend. Stacked, shoaling upward cycles of skeletal grainstones occur on the gentle ramp sides of tilted fault blocks. In contrast, a different style of lake margin accumulation occurs on the bounding fault side of these blocks. Blocks with single major bounding faults have narrow shelves prohibiting accumulation of carbonate, whereas structures with sets of subsidiary faults form perched platforms ideal for the accumulation of thick lacustrine carbonate sections. Both of these play types have good modern analogues from the Great Salt Lake in Utah and the East African Rift System.

  6. Exploration models for Tertiary lacustrine carbonates, Liaodong Bay, People's Republic of China

    SciTech Connect

    Lomando, A.J. )

    1996-01-01

    Lacustrine carbonates are a significant reservoir target in the basins of eastern China. Difficulty in seismically imaging this play type generates the need for accurate exploration models to define geometries for lead and prospect identification. Rifted and karsted Cambro-Ordovician carbonates form the base of the section which is overlain by thick Tertiary lacustrine deposits. Two types of lacustrine carbonate plays have been identified. Carbonate alluvial fans developed from the erosion of Cambro-Ordovician dolomites and limestones in places along the flanks of tilted fault block ridges. During lake formation and expansion, these fans formed small shelves along the lake margins which became the sites of active carbonate production and winnowing. This play type forms discontinuous trends of lacustrine shoreline skeletal grainstones which mimic the underlying fan geometries. A second play type was identified in the JZ-20/JZ-9 trend. Stacked, shoaling upward cycles of skeletal grainstones occur on the gentle ramp sides of tilted fault blocks. In contrast, a different style of lake margin accumulation occurs on the bounding fault side of these blocks. Blocks with single major bounding faults have narrow shelves prohibiting accumulation of carbonate, whereas structures with sets of subsidiary faults form perched platforms ideal for the accumulation of thick lacustrine carbonate sections. Both of these play types have good modern analogues from the Great Salt Lake in Utah and the East African Rift System.

  7. Play: Children's Business and a Guide to Play Materials.

    ERIC Educational Resources Information Center

    Markun, Patricia Maloney, Ed.

    This collection of articles presents ideas about the value of children's play and suggests practical ways to implement good play experiences and select appropriate play materials. Articles examine play as an agent of social values, play and thinking, play and child development, the environmental opportunities for play factors that can destroy the…

  8. Cohesive model applied to fracture propagation in Indiana Limestone

    NASA Astrophysics Data System (ADS)

    Dewers, T. A.; Rinehart, A. J.; Bishop, J. E.

    2014-12-01

    We apply a cohesive fracture (CF) model to results of short-rod (SR), notched 3-point-bend (N3PB) tests, and Brazil tests in Indiana Limestone. Calibration and validation of the model are performed within a commercial finite element modeling platform. By using a linear traction-displacement softening response for a defined fracture-opening displacement (w1) following peak tensile stress (σcrit), the CF model numerically lumps different spatially distributed inelastic processes occurring at and around fracture tips into a thin zone within an elastic domain. Both the SR and the N3PB test specimen geometries use a notch partway through the sample to control the location of fracture propagation. We develop a mesh for both the SR and N3PB geometries with a narrow cohesive zone in the center of notches. From the Brazil tests, we find a tensile splitting stress (σsplit) of 5.9 MPa. We use a σsplit as the peak tensile stress (σcrit) for all simulations. The Young's modulus (E) and the critical crack opening distance (w1) of the CF model are calibrated against the SR data. The model successfully captures the elastic, yield, peak, and initial and late failure behavior and compares favorably against the N3PB tests. Differences in force-displacement and crack propagation are primarily caused by: more mixed-mode (shear and opening) crack propagation in N3PB than in SR tests, causing a higher peak; and transition from compression (high E) to tension (low E) in a larger volume of the N3PB sample than in the SR geometry. This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy

  9. Field and laboratory experiments on high dissolution rates of limestone in stream flow

    NASA Astrophysics Data System (ADS)

    Hattanji, Tsuyoshi; Ueda, Mariko; Song, Wonsuh; Ishii, Nobuyuki; Hayakawa, Yuichi S.; Takaya, Yasuhiko; Matsukura, Yukinori

    2014-01-01

    Field and laboratory experiments were performed to examine dissolution rates of limestone in stream flow. Field experiments were conducted in three stream sites (A-C) with different lithological or hydrological settings around a limestone plateau in the Abukuma Mts., Japan. Sites A and B are allogenic streams, which flow from non-limestone sources into dolines, and site C has a karst spring source. Tablets made of limestone from the same plateau with a diameter of 3.5 cm and a thickness of 1 cm were placed in the streams for 3 years (2008-2011) where alkalinity, pH and major cation concentrations were measured periodically. The saturation indices of calcite (SIc) of stream water were - 2.8 ± 0.4 at site A, - 2.5 ± 0.4 at site B and - 0.5 ± 0.4 at site C. Annual weight loss ratios for tablets were extremely high at site A (0.11-0.14 mg cm- 2 d- 1), high at site B (0.05 mg cm- 2 d- 1), and low at site C (0.005 mg cm- 2 d- 1). The contrasting rates of weight loss are mainly explained by chemical conditions of stream water. In addition, laboratory experiments for dissolution of limestone tablets using a flow-through apparatus revealed that flow conditions around the limestone tablet is another important factor for dissolution in the stream environment. These results revealed that limestone dissolves at a rapid rate where water unsaturated to calcite continuously flows, such as in an allogenic stream.

  10. Optimization of Trona/Limestone Injection for SO2 Control in Coal-Fired Boilers

    SciTech Connect

    2005-09-01

    Mobotec USA develops and markets air pollution control systems for utility boilers and other combustion systems. They have a particular interest in technologies that can reduce NOx, SOx, and mercury emissions from coal-fired boilers, and have been investigating the injection of sorbents such as limestone and trona into a boiler to reduce SOx and Hg emissions. WRI proposed to use the Combustion Test Facility (CTF) to enable Mobotec to conduct a thorough evaluation of limestone and trona injection for SO{sub 2} control. The overall goal of the project was to characterize the SO{sub 2} reductions resulting from the injection of limestone and trona into the CTF when fired with a high-sulfur eastern bituminous coal used in one of Mobotec's Midwest installations. Results revealed that when limestone was injected at Ca:S molar ratios of 1.5 to 3.0, the resulting SO{sub 2} reductions were 35-55%. It is believed that further reductions can be attained with improved mixing of the sorbent with the combustion gases. When limestone was added to the coal, at Ca:S molar ratios of 0.5 to 1.5, the SO{sub 2} reductions were 13-21%. The lower reductions were attributed to dead-burning of the sorbent in the high temperature flame zone. In cases where limestone was both injected into the furnace and added to the coal, the total SO{sub 2} reductions for a given Ca:S molar ratio were similar to the reductions for furnace injection only. The injection of trona into the mid-furnace zone, for Na:S molar ratios of 1.4 to 2.4, resulted in SO{sub 2} reductions of 29-43%. Limestone injection did not produce any slag deposits on an ash deposition probe while trona injection resulted in noticeable slag deposition.

  11. Mineralogical characterization of the Shelburne Marble and the Salem limestone: Test stones used to study the effects of acid rain

    SciTech Connect

    McGee, E.S.

    1989-01-01

    The Salem Limestone and the Shelburne Marble are representative of limestones and marbles commonly used in buildings and monuments. Both stones are composed predominantly of calcite. The Salem Limestone is homogeneous in composition and mineralogic characteristics throughout the test block. The Shelburne Marble has compositionally homogeneous mineral phases, but the distribution of those phases within the test block is random. The mineralogy and physical characteristics of the Shelburne Marble and Salem Limestone test blocks described in the study provide a baseline for future studies of the weathering behavior of these stones. Because the Shelburne Marble and the Salem Limestone are representative of typical commercial marbles and limestones, they are likely to be useful in a consortium study of the effects of acid precipitation on these two types of building stones.

  12. Dynamic responses of photosystem II in the Namib Desert shrub, Zygophyllum prismatocarpum, during and after foliar deposition of limestone dust.

    PubMed

    van Heerden, P D R; Krüger, G H J; Kilbourn Louw, M

    2007-03-01

    The effects of limestone dust deposition on vegetation in desert ecosystems have not yet been reported. We investigated these effects in a succulent shrub from the Namib Desert at a limestone quarry near Skorpion Zinc mine (Namibia). Effects of limestone dust were determined in Zygophyllum prismatocarpum (dollar bush) plants with heavy, moderate and no visible foliar dust cover by means of chlorophyll a fluorescence measurements. Limestone dust deposition decreased overall plant performance through loss of chlorophyll content, inhibition of CO(2) assimilation, uncoupling of the oxygen-evolving complex and decreased electron transport. Importantly, dynamic recovery occurred after termination of limestone extraction at the quarry. Recovery was accelerated by rainfall, mainly because of dust removal from leaves and stimulation of new growth. These results indicate that limestone dust has severe effects on photosynthesis in desert shrubs, but that recovery is possible and that, in arid environments, this process is modulated by rainfall.

  13. Game-playing epilepsy.

    PubMed

    Siegel, M; Kurzrok, N; Barr, W B; Rowan, A J

    1992-01-01

    A 25-year-old woman with documented generalized seizures evoked by playing checkers was given a battery of psychological tests as well as a series of cognitive and non-game-related tasks during a session of intensive EEG-video monitoring. Generalized epileptiform discharges during each task, as well as during intervals of checkers playing, were quantified to determine possible triggering factors. Previous reports have discussed the roles of attention, concentration, stress, thinking, and spatial processing in similar cases. Our analysis showed significant activation of the EEG only with tasks involving strategic thinking, i.e., considering a sequence of moves based on evaluating the consequences of previous moves.

  14. Looking into Children's Play Communities

    ERIC Educational Resources Information Center

    Mabry, Mark; Fucigna, Carolee

    2009-01-01

    Play, particularly children's sociodramatic play, is the cornerstone of early childhood classrooms in the United States. Early childhood educators learn and expound mantras of "the value of play," "play-based programs," "children learning through play," and "play as child's work." They strive to promote the importance of making a place for play in…

  15. Play Therapy: Client-Centered Counseling for Elementary School Children.

    ERIC Educational Resources Information Center

    DeMaagd, Joan

    The value and importance of creative activities and play opportunities in play therapy is reviewed and discussed. Play therapy is considered to be part of the non-directive client-centered approach to counseling developed by Carl Rogers. The importance of giving the child the opportunity to play out his feelings and explore his thoughts and…

  16. The Development of Play as the Development of Consciousness.

    ERIC Educational Resources Information Center

    McCune, Loraine

    1993-01-01

    Argues that the capacity for consciousness of self and others arises from developing representational and perceptual activities, especially during play. Examines young children's development of symbolic play, from sensorimotor exploration to representational play through five stages involving gestures of recognition, self-pretend and pretend play,…

  17. One Thing Leads to Another: Evolution, Play, and Technology

    ERIC Educational Resources Information Center

    Narey, Teresa A.

    2010-01-01

    Traditionally, we think of play as children's work, and this work is often considered trivial and meaningless. However, when the definition of play is explored, its multiple meanings encourage us to understand play as an important vehicle for the propulsion of society. Play has become a hot topic in households and classrooms and for political…

  18. Play Deprivation: Is It Happening In Your School?

    ERIC Educational Resources Information Center

    Lauer, Lisa M.

    2011-01-01

    High-stakes testing combined with the notion that indoor and outdoor spontaneous play are a "waste of time" have contributed to the condition known as "play deprivation". This paper defines the term play deprivation and explores its negative effects on children and adults. Negative effects resulting from play deprivation include an increase in…

  19. Exploring Writing with Non-Academics.

    ERIC Educational Resources Information Center

    Phillips, Jerry

    Three adult males met 2 hours a week for 26 weeks in a non-academic setting to explore writing. Adult One (A-1) and Adult Two (A-2) were limestone miners and close friends. Adult Three (A-3) had some limited academic writing experience, so A-1 and A-2 thought that he knew more about what made writing effective. A-3 observed the others' writing…

  20. Emotionality and intentionality in bonobo playful communication.

    PubMed

    Demuru, Elisa; Ferrari, Pier F; Palagi, Elisabetta

    2015-01-01

    Great apes show very complex systems for communicating emotions and intentions. Whereas gestures are intentional signals, facial expressions can disclose both emotions and intentions. The playful context is a good field to explore the possible dichotomy between intentionally and emotionally driven signals as it has been suggested that one of its functions is to learn producing and decoding communicative patterns. To understand how signals are produced during play and how they are modified in the course of ontogeny, we investigated the use of playful facial expressions and gestures in bonobos (Pan paniscus), a tolerant species showing a high propensity to play even as adults. Our results showed that the use of play faces and gestures is strongly influenced by the characteristics of the play session. Both play faces and gestures were more often performed when social play involved physical contact and when the receiver was visually attending, thus suggesting that both signals can be strategically employed when communicating becomes more urgent. Compared to play faces, gestures were more frequent during dyadic than polyadic sessions, when a unique receiver was involved. Being gestures not context specific, they are probably used more selectively by the sender. On the contrary, play faces are context specific and transmit an unequivocal positive message that cannot be misconceived. These features legitimize a broad use of playful facial expressions, independently of the number of playmates. The similarities and differences in the production of these signals are probably linked to the different degree of emotionality and intentionality characterizing them. PMID:25204682

  1. Emotionality and intentionality in bonobo playful communication.

    PubMed

    Demuru, Elisa; Ferrari, Pier F; Palagi, Elisabetta

    2015-01-01

    Great apes show very complex systems for communicating emotions and intentions. Whereas gestures are intentional signals, facial expressions can disclose both emotions and intentions. The playful context is a good field to explore the possible dichotomy between intentionally and emotionally driven signals as it has been suggested that one of its functions is to learn producing and decoding communicative patterns. To understand how signals are produced during play and how they are modified in the course of ontogeny, we investigated the use of playful facial expressions and gestures in bonobos (Pan paniscus), a tolerant species showing a high propensity to play even as adults. Our results showed that the use of play faces and gestures is strongly influenced by the characteristics of the play session. Both play faces and gestures were more often performed when social play involved physical contact and when the receiver was visually attending, thus suggesting that both signals can be strategically employed when communicating becomes more urgent. Compared to play faces, gestures were more frequent during dyadic than polyadic sessions, when a unique receiver was involved. Being gestures not context specific, they are probably used more selectively by the sender. On the contrary, play faces are context specific and transmit an unequivocal positive message that cannot be misconceived. These features legitimize a broad use of playful facial expressions, independently of the number of playmates. The similarities and differences in the production of these signals are probably linked to the different degree of emotionality and intentionality characterizing them.

  2. Limestones as a paleobathymeter for reconstructing past seismic activities: Muroto-misaki, Shikoku, southwestern Japan

    NASA Astrophysics Data System (ADS)

    Iryu, Y.; Maemoku, H.; Yamada, T.; Maeda, Y.

    2009-03-01

    Muroto-misaki (Cape Muroto) is located at the southern tip of the eastern half of Shikoku, southwestern Japan and is ~ 100 km north of the Nankai Trough where the Philippine Sea Plate is being subducted beneath the Eurasian Plate. Therefore, the Muroto-misaki area has been seismically uplifted. Sedimentologic analyses were conducted on Holocene limestones that occur along the coast from Muroto-misaki to Meoto-iwa, located ~ 13 km north of the cape. The limestones are limited to less than 9.2 m in elevation. The limestones are up to 4.4 m in mean diameter, up to 0.5 m in thickness, and consist mainly of fossilized sessile organisms, including annelids, corals, bryozoans, encrusting foraminifers, barnacles, nongeniculate coralline algae, and, to a lesser extent, molluscs and peyssonneliacean algae. Acicular and equant cements are minor components. Acicular cements are found in semi-closed spaces between coralline algal crusts and their substrates. The modal composition of limestones was determined by a point-counting technique. Based on the biotic composition, the Holocene limestones can be classified into six types (Types I to VI). A comparison of the vertical distribution of these rock types with that of modern sessile organisms indicates that the top of Type I limestone, which is characterized by the occurrence of hermatypic corals, corresponds approximately to the mean low water springs when the limestones formed. A difference in the highest occurrence of Type I limestone between two sites may represent the variation in the total amount of uplift over the last 1000 to 1500 years, which resulted in an apparent northward decline of paleo-mean low water springs at a rate of ~ 10 cm/km. Therefore, the Holocene limestones are a good paleobathymeter to reconstruct past seismic activities in this area. This study shows that warm temperate carbonate deposits are as excellent recorders of geologic events, such as the timing and scale of repeated coseismic uplifts and

  3. Acid mine drainage treatment with a combined wetland/anoxic limestone drain: Greenhouse and field systems

    SciTech Connect

    Skousen, J.; Sexstone, A.; Cliff, J.; Sterner, P.; Calabrese, J.; Ziemkiewicz, P.

    1999-07-01

    The most common methods for treating acid mine drainage (AMD) involve applying a strong base to neutralize the acidity and to precipitate metals. Limestone use in AMD treatment has been largely confined to anaerobic wetlands, anoxic limestone drains (ALDs) and open limestone channels. If Fe{sup 3+} and Al could be removed from AMD before introduction into limestone systems, then the use of limestone for AMD treatment could be greatly expanded. The authors developed and monitored a passive AMD system to determine if AMD containing Fe{sup 3+} as ferrous sulfides (FeS{sub x}) through sulfate reduction. Further, Fe and al may be adsorbed to organic matter in the wetland thereby eliminating the formation of metal hydroxides with subsequent plugging of limestone pores. A field scale wetland/anoxic limestone drain (WALD) system located at Douglas, WV exported net alkaline water (mean of 127 mg/L as CaCO{sub 3}) for one year. However, dissolved oxygen and Fe data suggest that poor hydraulic conductivity caused this system to act as an Fe-oxidizing system, rather than an Fe-reducing system. As such, the system's long term effectiveness for treating AMD was compromised. After five years of operation, the system still reduces the acidity of the water from about 500 mg/L as CaCO{sub 3} to about 150 mg/L. A small scale Greenhouse system performed more like an Fe-reducing system, decreasing acidity for seven months and exporting Fe{sup 2+}, although the water existing the wetland did not contain excess alkalinity. While complications arose in the authors systems due to high flows in the Douglas system and high acidity in the Greenhouse system, pre-treating AMD with organic material can improve the condition of the water for proper treatment by an ALD or underlying limestone. For low to moderate flows (<400 L/min) and low Fe concentrations (<50 mg/L), a passive system that pre-treats AMD with organic substrates and then directs the water into limestone may be effective for many

  4. The Significance of Podpe limestone in the Cultural Heritage of Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Bedjanič, Mojca; Mirtič, Breda; Mladenović, Ana; Rožič, Boštjan; Skaberne, Dragomir; Zupančič, Nina

    2013-04-01

    Podpeč limestone is characterized by its dark grey, or nearly black colour, with white fossil shells of the Lithiotis. These beds, which have been dated as Lower Jurassic, occur in southern and south-western Slovenia, and are particularly common in areas southwest of Ljubljana. The main quarry, which is not active, is located next to the village of Podpeč near Ljubljana, and has been declared as a geological natural value of national importance; as such, it is officially protected as a natural monument. In the close vicinity of the village there are some other smaller quarries, but all of them have been abandoned. With its very low porosity (0.9%) and water absorption (0.13 - 0.30 % by mass), but relatively high compressive strength (185 MPa), this limestone is quite durable, although its colouring becomes somewhat bleached when situated outdoors. The use of Podpeč limestone was first documented in the case of the Roman period in Slovenia, when it was used for funerary stelae, votive altars, boundary stones, and other artefacts. At the end of the 5th Century AD, with the fall of the Roman Empire, stone-cutting ceased at Podpeč for the next few centuries. Before 1850 Podpeč limestone had no special value. Only very few portals or pilasters made of this stone are known, and no evidence has been found in churches. However, towards the end of the 19th Century Podpeč limestone became better-known, although before the first half of the 20th Century there were no significant stonecutting workshops in Podpeč. After this, stone was supplied progressively from the main quarry. Large numbers of buildings in Ljubljana and central Slovenia have sills, lintels and jambs made of Podpeč limestone. Production stopped in 1967. The internationally renowned Slovenian architect Jože Plečnik (1872-1957) used Podpeč limestone in various Slovenian buildings - the central stadium in Ljubljana, the National University Library, many altars and churches (Bogojina, the Ši\\vska and

  5. Actinobacterial diversity in limestone deposit sites in Hundung, Manipur (India) and their antimicrobial activities

    PubMed Central

    Nimaichand, Salam; Devi, Asem Mipeshwaree; Tamreihao, K.; Ningthoujam, Debananda S.; Li, Wen-Jun

    2015-01-01

    Studies on actinobacterial diversity in limestone habitats are scarce. This paper reports profiling of actinobacteria isolated from Hundung limestone samples in Manipur, India using ARDRA as the molecular tool for preliminary classification. A total of 137 actinobacteria were clustered into 31 phylotypic groups based on the ARDRA pattern generated and representative of each group was subjected to 16S rRNA gene sequencing. Generic diversity of the limestone isolates consisted of Streptomyces (15 phylotypic groups), Micromonospora (4), Amycolatopsis (3), Arthrobacter (3), Kitasatospora (2), Janibacter (1), Nocardia (1), Pseudonocardia (1) and Rhodococcus (1). Considering the antimicrobial potential of these actinobacteria, 19 showed antimicrobial activities against at least one of the bacterial and candidal test pathogens, while 45 exhibit biocontrol activities against at least one of the rice fungal pathogens. Out of the 137 actinobacterial isolates, 118 were found to have at least one of the three biosynthetic gene clusters (PKS-I, PKS-II, NRPS). The results indicate that 86% of the strains isolated from Hundung limestone deposit sites possessed biosynthetic gene clusters of which 40% exhibited antimicrobial activities. It can, therefore, be concluded that limestone habitat is a promising source for search of novel secondary metabolites. PMID:25999937

  6. Dietary adaptations of Assamese macaques (Macaca assamensis) in limestone forests in Southwest China.

    PubMed

    Huang, Zhonghao; Huang, Chengming; Tang, Chuangbin; Huang, Libin; Tang, Huaxing; Ma, Guangzhi; Zhou, Qihai

    2015-02-01

    Limestone hills are an unusual habitat for primates, prompting them to evolve specific behavioral adaptations to the component karst habitat. From September 2012 to August 2013, we collected data on the diet of one group of Assamese macaques living in limestone forests at Nonggang National Nature Reserve, Guangxi Province, China, using instantaneous scan sampling. Assamese macaques were primarily folivorous, young leaves accounting for 75.5% and mature leaves an additional 1.8% of their diet. In contrast, fruit accounted for only 20.1%. The young leaves of Bonia saxatilis, a shrubby, karst-endemic bamboo that is superabundant in limestone hills, comprised the bulk of the average monthly diet. Moreover, macaques consumed significantly more bamboo leaves during the season when the availability of fruit declined, suggesting that bamboo leaves are an important fallback food for Assamese macaques in limestone forests. In addition, diet composition varied seasonally. The monkeys consumed significantly more fruit and fewer young leaves in the fruit-rich season than in the fruit-lean season. Fruit consumption was positively correlated with fruit availability, indicating that fruit is a preferred food for Assamese macaques. Of seventy-eight food species, only nine contributed >0.5% of the annual diet, and together these nine foods accounted for 90.7% of the annual diet. Our results suggest that bamboo consumption represents a key factor in the Assamese macaque's dietary adaptation to limestone habitat.

  7. Depositional facies and diagenetic history of Trenton Limestone in northern Indiana

    SciTech Connect

    Fara, D.R.; Keith, B.D.

    1984-12-01

    Subsurface cores were studied petrographically to determine the facies and diagenetic history of the Trenton Limestone on a regional scale in northern Indiana. The Trenton Limestone is a yellowish olive-gray fossiliferous limestone, which is replaced by a light-gray dolostone in northern Indiana. Facies composing the Trenton are: 1) bryozoan-echinoderm packstone, 2) bryozoan-echinoderm grainstone, 3) bryozoan packstone to wackestone, 4) lime mudstone, and 5) dolostone. The bryozoan-echinoderm packstone is the major facies. Coarse-grained (1-4 mm) grainstones are typically 1 ft (30 cm) thick, have abrupt bases, and become muddy upward. They are considered storm deposits. Hardgrounds occur throughout the limestone facies, but they are most numerous toward the base. These facies indicate deposition below wave base, interrupted by periods of high energy during storms. Fossiliferous white and gray chert nodules are scattered throughout the unit. Also found in the limestone facies are prevalent stylolites and microstylolites, an indication of chemical compaction. The dolostone facies consists of coarsely crystalline (0.4 mm) idiotopic dolomite. Pyrite is associated with the dolomite. Porosity, found only in the dolostone, is discontinuous and characterized as intercrystalline, vuggy, and moldic. Porous zones are commonly oil stained or have been plugged by poikilotopic selentic gypsum. Minor amounts of celestite are found as cavity fillings.

  8. Stratigraphy and diagenesis of the Mississippian Lodgepole Limestone, Williston Basin, North Dakota

    SciTech Connect

    Grover, P.W.

    1996-12-31

    Stratigraphic correlation of the Lodgepole Limestone (Bottineau Interval) indicates a sequence of three clinoform-shaped wedges that filled in the early Williston Basin. To date four productive 100m thick mounds have been discovered in the Lodgepole Limestone at Dickinson Field. The mounds seem to have nucleated at the toe of slope of the first highstand system tract and were subsequently buried by the second highstand systems tract. By isopaching each of the systems tracts one can predict were other mounds might have nucleated. Burial depth of the Bakken Shale-Lodgepole Limestone contact grade from 0.6 km at the edge of the Williston Basin to 3.4 km in the center. With increased depth the basal Lodgepole Limestone shows three phases of dolomitization, which are: small clear early dolomite; later iron rich fracture filling saddle dolomite and a later iron rich dolomite that seems to follow stylolites. Pre-oil migration mineralization of the overlying limestone include minor amounts of: anhydrite, pyrite, iron poor sphalerite, late iron rich sphalerite, chalcopyrite and celestite.

  9. Stratigraphy and diagenesis of the Mississippian Lodgepole Limestone, Williston Basin, North Dakota

    SciTech Connect

    Grover, P.W. )

    1996-01-01

    Stratigraphic correlation of the Lodgepole Limestone (Bottineau Interval) indicates a sequence of three clinoform-shaped wedges that filled in the early Williston Basin. To date four productive 100m thick mounds have been discovered in the Lodgepole Limestone at Dickinson Field. The mounds seem to have nucleated at the toe of slope of the first highstand system tract and were subsequently buried by the second highstand systems tract. By isopaching each of the systems tracts one can predict were other mounds might have nucleated. Burial depth of the Bakken Shale-Lodgepole Limestone contact grade from 0.6 km at the edge of the Williston Basin to 3.4 km in the center. With increased depth the basal Lodgepole Limestone shows three phases of dolomitization, which are: small clear early dolomite; later iron rich fracture filling saddle dolomite and a later iron rich dolomite that seems to follow stylolites. Pre-oil migration mineralization of the overlying limestone include minor amounts of: anhydrite, pyrite, iron poor sphalerite, late iron rich sphalerite, chalcopyrite and celestite.

  10. Forest seasonality shapes diet of limestone-living rhesus macaques at Nonggang, China.

    PubMed

    Tang, Chuangbin; Huang, Libin; Huang, Zhonghao; Krzton, Ali; Lu, Changhu; Zhou, Qihai

    2016-01-01

    Limestone forests are an unusual habitat for primates, but little information is available for the genus Macaca in such habitats, making a comparative understanding of extant limestone primates' behavioral adaptation incomplete. We collected data on the diet of rhesus macaques (Macaca mulatta) in a limestone habitat at Nonggang Nature Reserve, southwestern Guangxi, China, and examined the effects of forest seasonality on their diet. Our results indicated that a total of 114 species of plants are consumed by macaques. Young leaves are a preferred food, accounting for 48.9 and 56.9% of the overall diets. One group significantly increased young leaf consumption in response to availability. Fruits contributed to only 27.3 and 28.7% of overall diet. The macaque diet varied according to season. They fed on more fruits in the rainy season. Consumption of mature leaves increased when the availability of young leaves and fruits declined in the dry season, indicating that mature leaves are a fallback food for macaques in a limestone habitat. Similar to sympatric Assamese macaques, Bonia saxatilis, a shrubby, karst-endemic bamboo was consumed by rhesus macaques throughout the year, and was the top food species through most of the year, suggesting that bamboo consumption represents a key factor in the macaque's dietary adaptation to limestone habitat.

  11. Field Test of Limestone as a Treatment Medium for Groundwater at the Savannah River Site

    SciTech Connect

    Ekechukwu, A.A.

    2001-04-10

    Groundwater downgradient from the F- and H-Area Seepage Basins at the Savannah River Site is contaminated with acids, metals, radionuclides, and tritium originally released as part of low-level waste streams from the Radiochemical Separations Areas processing facilities. To stem the flux of tritium discharged from the basin area, a series of wells was installed to extract the groundwater and re-inject it upgradient of the seepage basins. Tritium is captured in an extraction-re-injection cycle that allows it to decay. To meet regulatory criteria for re-injection, metals and radionuclides must be treated and removed. One method under consideration for this removal is in-situ contact with limestone. Equilibration of the groundwater with limestone raises the pH to approximately 8. At this pH, metals and radionuclides can be removed by direct precipitation, co-precipitation, and enhanced adsorption. A pilot test was performed to provide data required to assess the applicability of limestone in groundwater treatment. The demonstration unit consisted of several columns of limestone with different total column lengths and thus different residence times. Ground water from the basins was passed through each of the columns and analyzed for metals, radionuclides, ions, pH, and alkalinity. The results from both the laboratory and field tests show the limestone's effectiveness as an in-situ treatment medium.

  12. Effect of magnesium salts on the sulphation capacity of limestone slurry

    SciTech Connect

    Ozyuguran, A.; Altun-Ciftcioglu, G.; Karatepe, N.; Ersoy-Mericboyu, A.

    2006-09-15

    The effect of different magnesium salts such as MgO, MgSO{sub 4}.7H{sub 2}O and Mg(OH){sub 2} on the total sulphation capacities of limestone slurries prepared from five different limestone samples was investigated. Sulphation reactions of slurries were conducted at a constant temperature of 323 K in a gaseous mixture consisting of 5% O{sub 2}, 10% CO{sub 2}, 0.5% SO{sub 2} and a balance of nitrogen by volume. It was found that the total sulphation capacities of limestone slurries increased with the addition of MgO and Mg(OH){sub 2} salts and decreased with the addition of MgSO{sub 4}.7H{sub 2}O salt. Depending on the chemical composition of the limestone samples the total sulphation capacities of limestone slurries were increased between 22.30% and 75.00% by MgO addition and between 23.70% and 69.00% by Mg(OH){sub 2} addition.

  13. Discrimination of reservoir dolostone within tight limestone using rock physics modeling and pre-stack parameters

    NASA Astrophysics Data System (ADS)

    Park, G.; Lee, B.; Lee, G.

    2013-12-01

    Dolostones may be differentiated from limestones based on various pre-stack seismic parameters as they are denser and faster. However, because the seismic properties of a rock are affected strongly by porosity, porous dolostones may not be significantly denser and faster than limestones. We computed various pre-stack parameters (P-impedance, S-impedance, Vp/Vs, Poisson's ratio, Lamé constants) for tight limestones using the Vp and density logs from a well that penetrated Jurassic carbonate and the Vs log, constructed from the empirical relationships of Vp and Vs. The pre-stack parameters of dolostones with 1% - 40% porosity were estimated based on the bulk and shear moduli and bulk densities computed from the formulas proposed by various workers, including Gassmann equations. Crossplots of the pre-stack parameters show that the Lamé constants (λ, μ) are most effective in differentiating dolostones from limestones. In particular, the λρ -μρ vs. μρ crossplot shows a clear-cut separation of the porous dolostones and tight limestones; the porous dolostones plot exclusively to the left of the λρ -μρ of about 25 GPa.

  14. Influence of clay swelling on the mechanical behaviour of Egyptian Helwan limestone

    NASA Astrophysics Data System (ADS)

    Aly, Nevin

    2016-04-01

    Clay minerals exist naturally in the majority of different Egyptian limestones types. Changes in the dimensions of clays during swelling / shrinking process induced by changes in the environmental conditions can result in acceleration the deterioration of the hosting stone. Petrographic investigation by scanning - electron microscope (SEM) of Helwan limestone (biomicritic limestone) revealed distribution of a typical smectite morphology (curled - leaf shape) beside abundance of glauconite pellets within the stone material. The clay frication extracted from Helwan reached 10% and oriented aggregates samples were analyzed by X- ray diffraction (XRD) and confirmed the identification of smectite as the main mineral in the clay frication. To study the effect of the clay content on the mechanical behavior of Helwan limestone, hygric swelling test was performed at first by using displacement sensor and then the effect of multiple wetting/ drying cycles on the stone strength was determined using unconfined compressive strength (UCS). Results revealed that there was a significant correlation between degree of swelling of the clay and strength of the limestone.

  15. [Effect of limestone and magnesite application on remediation of acidified forest soil in Chongqing, China].

    PubMed

    Yang, Yong-sen; Duan, Lei; Jin, Teng; Zhao, Da-wei; Zhang, Dong-bao; Hao, Ji-ming

    2006-09-01

    Effect of limestone and magnesite application on remediation of a typical acidified soil under a masson pine (Pinus massoniana) forest at Tieshanping, Chongqing in southwest China was studied through field experiments. The changes of soil water chemistry in different layers within one year after application of limestone or magnesite indicated that the remediation agents leaded to the recovery of acidified soil by significant increase of pH value and concentration of relative cation, i.e., Ca2+ or Mg2+, and notable decrease of inorganic monomeric aluminum (Ali). However, the accelerated leaching of NO3- and SO4(2-) might somewhat counteract the positive effects. Since the limestone powder applied was much finer and thus more soluble than the magnesite powder, it seemed that the addition of limestone was more effective than that of magnesite. However, the application of magnesite could probably improve the nutrient uptake and growth of plant, and thus limestone and magnesite should be used together. The change of soil water chemistry was much more notable in upper layer of soil than lower, which means that it will take long time to achieve the whole profile soil remediation.

  16. Fluoride removal from groundwater by limestone treatment in presence of phosphoric acid.

    PubMed

    Gogoi, Sweety; Nath, Suresh K; Bordoloi, Shreemoyee; Dutta, Robin K

    2015-04-01

    Fluoride removal from groundwater has been studied by addition of dilute phosphoric acid (PA) to the influent water before limestone treatment through laboratory plug-flow column experiments and bench-scale plug-flow pilot tests. In this PA-enhanced limestone defluoridation (PAELD) technique, fluoride is removed from 0.526 mM to 0.50-52.60 μM in 3 h with near neutral final pH. The presence of PA increases the fluoride removal capacity of limestone to 1.10 mg/g compared to 0.39 mg/g reported in its absence. The changes in fluoride removal with variation in initial PA concentration, initial fluoride concentration and the final pH have been found to be statistically significant with p < 0.05. The estimated recurring cost is US$ ≈0.58/m(3) water. Simple scrubbing and rinsing is a preferable method for regeneration of limestone as it is almost equally effective with lime or NaOH. Sorption of fluoride by calcium phosphates produced in situ in the reactor is the dominant mechanism of fluoride removal in the PAELD. Precipitation of CaF2 and sorption of fluoride by the limestone also contribute to the fluoride removal. High efficiency, capacity, safety, environment-friendliness, low cost and simplicity of operation make the PAELD a potential technique for rural application. PMID:25621387

  17. The effects of lichen cover upon the rate of solutional weathering of limestone

    NASA Astrophysics Data System (ADS)

    McIlroy de la Rosa, J. P.; Warke, P. A.; Smith, B. J.

    2014-09-01

    The contribution of lichens to the biomodification of limestone surfaces is an area of conflict within bioweathering studies, with some researchers suggesting a protective effect induced by lichen coverage and others a deteriorative effect induced by the same organisms. Data are reported demonstrating the potential role of endolithic lichen, in particular of Bagliettoa baldensis, in the active protection of Carboniferous limestone surfaces from rainfall-induced solutional weathering. During a 12-month microcatchment exposure period in the west of Northern Ireland, average dissolutional losses of calcium are greater from a lichen-free limestone surface compared with a predominantly endolithic lichen-covered surface by just under 1.25 times. During colder winter months, the lichen-free surface experiences calcium loss almost 1.5 times greater than the lichen-covered surface. Using extrapolation to upscale from the micro-catchment sample scale, for the year of sample exposure, the rate of calcium loss is 1.001 g m- 2 a- 1 from lichen-covered limestone surfaces and 1.228 g m- 2 a- 1 from lichen-free bare limestone surfaces. This research has implications for our understanding of karst environments, the contribution of lichens to karren development and the conservation of lichen-colonised dimension stone within a cultural setting.

  18. Forest seasonality shapes diet of limestone-living rhesus macaques at Nonggang, China.

    PubMed

    Tang, Chuangbin; Huang, Libin; Huang, Zhonghao; Krzton, Ali; Lu, Changhu; Zhou, Qihai

    2016-01-01

    Limestone forests are an unusual habitat for primates, but little information is available for the genus Macaca in such habitats, making a comparative understanding of extant limestone primates' behavioral adaptation incomplete. We collected data on the diet of rhesus macaques (Macaca mulatta) in a limestone habitat at Nonggang Nature Reserve, southwestern Guangxi, China, and examined the effects of forest seasonality on their diet. Our results indicated that a total of 114 species of plants are consumed by macaques. Young leaves are a preferred food, accounting for 48.9 and 56.9% of the overall diets. One group significantly increased young leaf consumption in response to availability. Fruits contributed to only 27.3 and 28.7% of overall diet. The macaque diet varied according to season. They fed on more fruits in the rainy season. Consumption of mature leaves increased when the availability of young leaves and fruits declined in the dry season, indicating that mature leaves are a fallback food for macaques in a limestone habitat. Similar to sympatric Assamese macaques, Bonia saxatilis, a shrubby, karst-endemic bamboo was consumed by rhesus macaques throughout the year, and was the top food species through most of the year, suggesting that bamboo consumption represents a key factor in the macaque's dietary adaptation to limestone habitat. PMID:26530218

  19. [Effect of limestone and magnesite application on remediation of acidified forest soil in Chongqing, China].

    PubMed

    Yang, Yong-sen; Duan, Lei; Jin, Teng; Zhao, Da-wei; Zhang, Dong-bao; Hao, Ji-ming

    2006-09-01

    Effect of limestone and magnesite application on remediation of a typical acidified soil under a masson pine (Pinus massoniana) forest at Tieshanping, Chongqing in southwest China was studied through field experiments. The changes of soil water chemistry in different layers within one year after application of limestone or magnesite indicated that the remediation agents leaded to the recovery of acidified soil by significant increase of pH value and concentration of relative cation, i.e., Ca2+ or Mg2+, and notable decrease of inorganic monomeric aluminum (Ali). However, the accelerated leaching of NO3- and SO4(2-) might somewhat counteract the positive effects. Since the limestone powder applied was much finer and thus more soluble than the magnesite powder, it seemed that the addition of limestone was more effective than that of magnesite. However, the application of magnesite could probably improve the nutrient uptake and growth of plant, and thus limestone and magnesite should be used together. The change of soil water chemistry was much more notable in upper layer of soil than lower, which means that it will take long time to achieve the whole profile soil remediation. PMID:17117649

  20. Tidal rhythmites infine-grained Carboniferous limestones, U.S.A.

    USGS Publications Warehouse

    Archer, A.W.; Feldman, H.R.

    1994-01-01

    Analyses of fine-grained limestones reveals that many exhibit fine-scale laminations. Laminations can be normally graded and consist of a coarser-grained lower part and a finer-grained upper part. The upper part can also contain finely disseminated organic material. Despite the similarities of such graded laminae to yearly varves and turbidites, it can be demonstrated by use of laminae-thickness periodicities that some graded laminae are reasonably interpreted as the product of tidal processes. Within siliciclastic systems, modern analogues of such processes are available for comparisons. In fine-grained facies of the Salem Limestone (Visean; Indiana, U.S.A.), periodicities observed within sequential-laminae thicknesses indicate a dominant control by neap-spring tidal processes. Similarly, laminae within limestones of the vertebrate-bearing Hamilton paleochannel (Stephanian; Kansas, U.S.) exhibit similar features, including fine-scale tidal bundles. This limestone is noted for the abundance of articulated fish fossils. Carbonates containing articulated fish from the Wild Cow Formation (Stephanian; New Mexico, U.S.), exhibit diffuse laminations; however, closely associated siliciclastic mudstones contain laminae that exhibit tidal periodicities. There are many similarities between tidal periodicities and patterns of lamination thicknesses of these rocks. A tidal interpretation for these rocks allows for localized, very rapid rates of deposition. Such rapid deposition may, in part, help to explain how articulated fish and other vertebrates can become preserved within such fine-grained limestones. ?? 1994.

  1. Fluoride removal from groundwater by limestone treatment in presence of phosphoric acid.

    PubMed

    Gogoi, Sweety; Nath, Suresh K; Bordoloi, Shreemoyee; Dutta, Robin K

    2015-04-01

    Fluoride removal from groundwater has been studied by addition of dilute phosphoric acid (PA) to the influent water before limestone treatment through laboratory plug-flow column experiments and bench-scale plug-flow pilot tests. In this PA-enhanced limestone defluoridation (PAELD) technique, fluoride is removed from 0.526 mM to 0.50-52.60 μM in 3 h with near neutral final pH. The presence of PA increases the fluoride removal capacity of limestone to 1.10 mg/g compared to 0.39 mg/g reported in its absence. The changes in fluoride removal with variation in initial PA concentration, initial fluoride concentration and the final pH have been found to be statistically significant with p < 0.05. The estimated recurring cost is US$ ≈0.58/m(3) water. Simple scrubbing and rinsing is a preferable method for regeneration of limestone as it is almost equally effective with lime or NaOH. Sorption of fluoride by calcium phosphates produced in situ in the reactor is the dominant mechanism of fluoride removal in the PAELD. Precipitation of CaF2 and sorption of fluoride by the limestone also contribute to the fluoride removal. High efficiency, capacity, safety, environment-friendliness, low cost and simplicity of operation make the PAELD a potential technique for rural application.

  2. Origin and Evolution of Limestone Caves of Chhattisgarh and Orissa, India: Role of Geomorphic, Tectonic and Hydrological Processes

    NASA Astrophysics Data System (ADS)

    Gautam, P. K.; Allu, N. C.; Ramesh, R.; Yadava, M. G.; Panigrahi, C. P.

    2014-12-01

    Carbonate rocks undergo karstic process and karst morphology is a key to understand the nature and genesis of caves. The primary energy source for the formation of karst landforms is hydrological cycle. Geomorphic features along with hydrological characteristics provide important information not only on karst formation but also climate and environmental conditions. In this paper, we present the tectonic and geomorphic features that played a role in evolution of caves located in Chhattisgarh and Orissa States of India. The geomorphic and tectonic aspects of Kotumsar, Kailash, and Gupteshwar caves are discussed in relation to the origin and evolution of these caves. Caves are located near the water falls. The area is folded and faulted along the Eastern Ghat Mobile Belt (EGMB) due to tectonic reactivation. Shaly-limestone beds exhibit vertical dipping near Gupteshwar cave, and steeply inclined near Kotumsar and Kailash caves. Indrāvati and Sabari/Kolab tributaries of the Godavari River drain the area. The landscape evolution and the origin of caves in the region is a multistage process, where the lithology, orogeny, fluvial action, and monsoon are the main agents, which is similar to the four state model (Ford and Ewers, 1978). The river basin evolution and regional tectonism also caused the initiation of karstification in the region. The evolution of caves is believed to have taken place in Pre-Pliocene under more humid conditions that coincided with the initiation of monsoon in India. Further, during the Quaternary wet-dry/cold-warm phases altered physical and chemical weathering of limestone rocks. Contrasting relief features of Bastar plateau have also helped the extensive cave formation in the region. The dissolution along weak planes initiated the openings of caves, further enlarged by geomorphic agents. Both monsoon and tectonics have caused fluctuations in water levels along river courses, which acted as active agents in evolution of caves.

  3. "Playing" with Science

    ERIC Educational Resources Information Center

    Allen, Dave

    2012-01-01

    When faced with a multitude of tasks, any opportunity to "kill two birds with one stone" is welcome. Drama has always excited the author: as a child performing in plays, later as a student and now as a teacher directing performances and improvising within lessons. The author was lucky enough to have inspirational teachers during his primary and…

  4. Play's Importance in School

    ERIC Educational Resources Information Center

    Sandberg, Anette; Heden, Rebecca

    2011-01-01

    The purpose of this study is to contribute knowledge on and gain an understanding of elementary school teachers' perspectives on the function of play in children's learning processes. The study is qualitative with a hermeneutical approach and has George Herbert Mead as a theoretical frame of reference. Interviews have been carried out with seven…

  5. Who's Calling the Plays?

    ERIC Educational Resources Information Center

    Goldman, Jay P.

    1990-01-01

    Without an enforceable policy, school athletics programs are beset by politics, high finance, and public sentiment. The most nettlesome problems include loss of instructional time to sports and extracurricular activities; the appropriateness and effectiveness of no-pass/no-play rules; lack of sportsmanship; proliferation of interstate competition;…

  6. Bicentennial Plays and Programs.

    ERIC Educational Resources Information Center

    Fisher, Aileen

    This book contains royalty-free material on bicentennial themes for presentation by schools and amateur groups. The first section, Plays and Pageants, contains "Our Great Declaration,""A Star for Old Glory,""Sing, America, Sing,""Washington Marches On,""When Freedom Was News," and "A Dish of Green Peas." The second section, Playlets and…

  7. Abstraction through Game Play

    ERIC Educational Resources Information Center

    Avraamidou, Antri; Monaghan, John; Walker, Aisha

    2012-01-01

    This paper examines the computer game play of an 11-year-old boy. In the course of building a virtual house he developed and used, without assistance, an artefact and an accompanying strategy to ensure that his house was symmetric. We argue that the creation and use of this artefact-strategy is a mathematical abstraction. The discussion…

  8. Writing as Play.

    ERIC Educational Resources Information Center

    Rensenbrink, Carla

    1987-01-01

    Reveals ways to help students learn that writing can be similar to play, in that they can use their imaginations to create new settings and even new worlds. Suggests using toys, imaginary trips, and including friends in stories as inspiration for writing. (SKC)

  9. The Games Children Play

    ERIC Educational Resources Information Center

    Padak, Nancy; Rasinski, Timothy

    2008-01-01

    The games that children play are not just for fun-they often lead to important skill development. Likewise, word games are fun opportunities for parents and children to spend time together and for children to learn a lot about sounds and words. In this Family Involvement column, the authors describe 12 easy-to-implement word games that parents and…

  10. Statistics at Play

    ERIC Educational Resources Information Center

    English, Lyn D.

    2014-01-01

    An exciting event had occurred for the grade 3 classes at Woodlands State School. A new play space designated for the older grades had now been opened to the third graders. In sharing their excitement over this "real treat, real privilege," the teachers invited the children to find out more about playgrounds and, in particular, their new…

  11. Integrated Play Groups

    ERIC Educational Resources Information Center

    Glovak, Sandra

    2007-01-01

    As an occupational therapist running social play groups with sensory integration for children on the autism spectrum, the author frequently doubted the wisdom of combining several children on the spectrum into a group. In fact, as the owner of a clinic she said, "No more!" The groups seemed like a waste of parents' time and money, and she refused…

  12. Playing It Safe.

    ERIC Educational Resources Information Center

    Jones, Rebecca

    1997-01-01

    Offers tips for avoiding sports-related injuries: (1) expect more of coaches; (2) develop an athletic-safety plan; (3) consider hiring an athletic trainer; (4) check facilities and equipment regularly; (5) recognize athletes' limitations; (6) take precautions beyond the playing field; and (7) check liability coverage and obtain informed consent.…

  13. Games Professors Play

    ERIC Educational Resources Information Center

    Kenny, James A.; Herzing, Thomas W.

    1969-01-01

    The games are Build a Reputation (REP), Confuse the Student (CON), Blame the Opposition (BOP), and Pass the Buck (BUCK). Professors play these games because they "want to show off on occasion, . . . want to get off the hook and avoid responsibility, . . . are prone to blame others, or simply because they are lazy. (WM)

  14. PlayWrite.

    ERIC Educational Resources Information Center

    Amodeo, Janis

    This report describes the PlayWrite Program, which was developed in the Montville Township School District, New Jersey, to encourage children in grades K-6 to write. The primary objectives of the program are to increase students' motivation to write; to improve their writing skills through the process of brainstorming, composing, revising, and…

  15. Creative Outdoor Play Areas.

    ERIC Educational Resources Information Center

    Miller, Peggy L.

    Considering the creation of proper play areas for children (school sites, municipal and mini parks, private homes and backyards, shopping centers, apartment complexes, recreational areas, roadside parks, nursery schools, churches, summer camps, and drive-in theaters) as one of today's major challenges, the author recommends that professional…

  16. One Play a Day

    ERIC Educational Resources Information Center

    Blankenship, Mark

    2007-01-01

    Undergraduate theater students rarely get the chance to work on a major world premiere, but this year hundreds of them will. Currently, more than 70 colleges and universities are participating in "365 Days/365 Plays," an ambitious project from Pulitzer Prize-winning playwright Suzan-Lori Parks. Every week, as they mount their portion of this epic…

  17. The Paradoxes of Play.

    ERIC Educational Resources Information Center

    Rokosz, Francis M.

    1988-01-01

    The article makes a case against the structuring of intramural sports programs on the basis of the varsity athletics model, arguing that the latter model's components of competition and aggression mar the former's intrinsic rewards of play, creativity, and enhanced human relationships. (CB)

  18. Exploratory and basic fluidized-bed combustion studies. Quarterly report, April-June 1980. [Limestone and dolomite; USA

    SciTech Connect

    Johnson, I.; Myles, K.M.; Swift, W.M.

    1980-12-01

    This work supports the development studies for both atmospheric and pressurized fluidized-bed coal combustion. Laboratory and process development studies are aimed at providing needed information on limestone utilization, removal of particles and alkali metal compounds from the flue gas, control of SO/sub 2/ and trace pollutant emissions, and other aspects of fluidized-bed coal combustion. This report presents information on: (1) the development of a sorbent utilization prediction methodology, (2) studies of factors which affect limestone breakup and elutriation, (3) basic studies of limestone sulfation under combustion conditions, and (4) studies of the kinetics of the hydration of spent limestone.

  19. Porosity development in the Copper Ridge Dolomite and Maynardville Limestone, Bear Creek Valley and Chestnut Ridge, Tennessee

    SciTech Connect

    Goldstrand, P.M.; Menefee, L.S.; Dreier, R.B.

    1995-12-01

    Matrix porosity data from deep core obtained in Bear Creek Valley indicate that porosities in the Maynardville Limestone are lithology and depth dependent. Matrix porosities are greater in the Cooper Ridge Dolomite than in the Maynardville Limestone, yet there is no apparent correlation with depth. Two interrelated diagenetic processes are the major controlling factors on porosity development in the Copper Ridge Dolomite and Maynardville Limestone; dissolution of evaporate minerals and dedolomitization. Both of these diagenetic processes produce matrix porosities between 2.1 and 1.3% in the Copper Ridge Dolomite and upper part of the Maynardville Limestone (Zone 6) to depths of approximately 600 ft bgs. Mean matrix porosities in Zones 5 through 2 of the Maynardville Limestone range from 0.8 to 0.5%. A large number of cavities have been intersected during drilling activities in nearly all zones of the Maynardville Limestone in Bear Creek Valley. Therefore, any maynardville Limestone zone within approximately 200 ft of the ground surface is likely to contain cavities that allow significant and rapid flow of groundwater. Zone 6 could be an important stratigraphic unit in the Maynardville Limestone for groundwater flow and contaminant transport because of the abundance of vuggy and moldic porosities. There are large variations in the thickness and lithology in the lower part of the Maynardville (Zones 2, 3, and 4 in the Burial Grounds region). The direction and velocity of strike-parallel groundwater flow may be altered in this area within the lower Maynardville Limestone.

  20. Play in America from Pilgrims and Patriots to Kid Jocks and Joystick Jockeys: Or How Play Mirrors Social Change

    ERIC Educational Resources Information Center

    Cross, Gary

    2008-01-01

    Drawing on a range of sources in the history of play, this article discusses how play for all ages mirrors social change, especially but not exclusively in America. The article explores three broad themes from colonial times to the present: first, how play was shaped by changes in work and time at work; second, how play activities were transformed…

  1. Suitability of two types of organic wastes for the growth of sclerophyllous shrubs on limestone debris: a mesocosm trial.

    PubMed

    Maisto, G; De Marco, A; De Nicola, F; Arena, C; Vitale, L; Virzo De Santo, A

    2010-03-01

    This study investigated whether overlaying organic wastes directly on limestone debris allowed the growth of sclerophyllous shrubs; the aim was to explore the feasibility of rehabilitation of sites destroyed by quarrying activity. In an open air mesocosm experiment two types of organic material were compared: compost from municipal wastes (C) and a mixture of compost and poultry manure added with wheat husk (C-PW). Mesocosms were pots (1m diameter, 60cm height) containing limestone debris covered by the organic material. Seven mesocosms with C and seven mesocosms with C-PW were planted with sclerophyllous shrubs (Laurus nobilis L., Phillyrea angustifolia L. and Quercus ilex L.). The substrates were characterised in terms of chemical and physical parameters, microbial activity and biomass, and total and active fungal biomass. Shrub photosynthetic performance and growth were evaluated. Over the whole experimental period, organic matter mineralization was higher in C-PW. Microbial biomass and respiration were higher in C-PW than in C but after one year no statistically significant difference between the two substrates occurred. Fungal mycelium was a minor fraction of the microbial community in both types of substrates and decreased dramatically after setting up the mesocosms. The metabolic quotient was higher in C suggesting more stressful conditions as compared to C-PW. Both substrates allowed shrub growth; however photosynthetic rates and the increase of plant size were higher on C-PW than on C. The results demonstrated that, as compared to only compost, the mixture of compost and poultry manure added with wheat husk is a substrate more suitable to both microbial processes and plant growth. Therefore a plan to revegetate quarries based on the use of organic wastes as a substrate for sclerophyllous shrubs could be feasible and, what is more, helpful to mitigate the environmental impact of organic wastes disposal. PMID:20092872

  2. Suitability of two types of organic wastes for the growth of sclerophyllous shrubs on limestone debris: a mesocosm trial.

    PubMed

    Maisto, G; De Marco, A; De Nicola, F; Arena, C; Vitale, L; Virzo De Santo, A

    2010-03-01

    This study investigated whether overlaying organic wastes directly on limestone debris allowed the growth of sclerophyllous shrubs; the aim was to explore the feasibility of rehabilitation of sites destroyed by quarrying activity. In an open air mesocosm experiment two types of organic material were compared: compost from municipal wastes (C) and a mixture of compost and poultry manure added with wheat husk (C-PW). Mesocosms were pots (1m diameter, 60cm height) containing limestone debris covered by the organic material. Seven mesocosms with C and seven mesocosms with C-PW were planted with sclerophyllous shrubs (Laurus nobilis L., Phillyrea angustifolia L. and Quercus ilex L.). The substrates were characterised in terms of chemical and physical parameters, microbial activity and biomass, and total and active fungal biomass. Shrub photosynthetic performance and growth were evaluated. Over the whole experimental period, organic matter mineralization was higher in C-PW. Microbial biomass and respiration were higher in C-PW than in C but after one year no statistically significant difference between the two substrates occurred. Fungal mycelium was a minor fraction of the microbial community in both types of substrates and decreased dramatically after setting up the mesocosms. The metabolic quotient was higher in C suggesting more stressful conditions as compared to C-PW. Both substrates allowed shrub growth; however photosynthetic rates and the increase of plant size were higher on C-PW than on C. The results demonstrated that, as compared to only compost, the mixture of compost and poultry manure added with wheat husk is a substrate more suitable to both microbial processes and plant growth. Therefore a plan to revegetate quarries based on the use of organic wastes as a substrate for sclerophyllous shrubs could be feasible and, what is more, helpful to mitigate the environmental impact of organic wastes disposal.

  3. "We Should Be Playing, Not Talking": Play, Self-Agency and Moving towards Depressive Moments

    ERIC Educational Resources Information Center

    Poynton, Margaret

    2012-01-01

    This paper describes the use of play in the psychotherapy of a latency child from a severely traumatised background. It considers the meaning of play in relation to the role of the psychotherapist and to psychotherapeutic technique and explores its functions in terms of the child's development. The paper documents the psychotherapist's learning…

  4. Games People Play.

    ERIC Educational Resources Information Center

    Linacre, John Michael; Fisher, Patrick

    1998-01-01

    The two articles of this theme section consider problems of measurement in relation to games. "How Good was Bobby Fischer in 1992?" (John Michael Linacre) explores a Rasch analysis of the chess performance of Bobby Fischer, while "Objective Analysis of Golf" (Patrick Fisher) considers measurement problems presented by golf. (SLD)

  5. Supervising the uncanny: the play within the play.

    PubMed

    Leader, Carol

    2015-11-01

    The writer offers a combined experience in analysis and the performing arts to explore uncanny aspects of the unconscious subtext of the patient's inner drama; subtext which can remain hidden from view in supervision. Freud and Jung's understanding of uncanny experience is considered together with a painting from medieval alchemy and Matte Blanco's conceptions concerning the symmetrical nature of unconscious process. Theatre and the work of the theatre director and actor in approaching the multidimensional aspects of a play are then introduced. Finally clinical case material from group supervision demonstrates how the 'theatre of therapy' and the work of the supervisory couple and group promote the emergence of a more authentic conscious asymmetrical response to the patient's 'script' that can break the 'spell' of the transference/countertransference relationship. This in turn brings meaning to the underlying and implicit 'stage directions' that the patient has been unconsciously communicating.

  6. Supervising the uncanny: the play within the play.

    PubMed

    Leader, Carol

    2015-11-01

    The writer offers a combined experience in analysis and the performing arts to explore uncanny aspects of the unconscious subtext of the patient's inner drama; subtext which can remain hidden from view in supervision. Freud and Jung's understanding of uncanny experience is considered together with a painting from medieval alchemy and Matte Blanco's conceptions concerning the symmetrical nature of unconscious process. Theatre and the work of the theatre director and actor in approaching the multidimensional aspects of a play are then introduced. Finally clinical case material from group supervision demonstrates how the 'theatre of therapy' and the work of the supervisory couple and group promote the emergence of a more authentic conscious asymmetrical response to the patient's 'script' that can break the 'spell' of the transference/countertransference relationship. This in turn brings meaning to the underlying and implicit 'stage directions' that the patient has been unconsciously communicating. PMID:26499298

  7. Freshwater biodissolution rates of limestone in the temperate climate of the Dinaric karst in Slovenia

    NASA Astrophysics Data System (ADS)

    Mulec, J.; Prelovšek, M.

    2015-01-01

    Dissolution rates in two freshwater karst systems were determined by using tablets of dense micrite-biopelmicrite Cretaceous limestone. Submerged limestone tablets in riverbeds were subjected to a natural gradient from complete darkness to direct sunlight. Higher light rates significantly (p < 0.05) increased the epilithic biomass of phototrophs and the overall dissolution rates, which were highest at the Unica spring (- 49.2 μm a- 1), but the exact portion of light-dependent dissolution remains elusive. In the karst river Unica, with its big fluctuations in environmental parameters (e.g., discharge), light rates can be used in estimating the dissolution rates enhanced by phototrophs. Natural biofilms in aquatic systems have important implications for landform evolution, and the impact on limestone dissolution rates is comparable with rates of debris falling from steep slopes.

  8. Search for high-calcium limestone in Silurian reefs of northern Indiana.

    USGS Publications Warehouse

    Ault, C.H.; Carr, D.D.

    1981-01-01

    During Silurian time, the Indiana part of the Wabash Platform was a shallow-water area between the proto-Illinois and proto- Michigan Basins and a site of growth of hundreds, or perhaps thousands, of reefs. Today, most reefs of northern Indiana are dolomite, but some are dolomitic limestone, and a few are limestone of high purity in deposits that can be mined by openpit methods. Four of the five generations of reefs of Silurian age in the Great Lakes area have been recognized in northern Indiana. All known limestone reefs are restricted to an area of six countries in north-central Indiana, although no apparent depositional environment as revealed from study of surrounding inter-reef rocks has been found to account for any restriction. Dolomitization is more likely related to the textures and lithologies of the individual reefs.-from Authors

  9. Chitinozoans in the Ordovician (Caradocian) Ridley and Pierce Limestones of central Tennessee

    SciTech Connect

    Kessler, T.E.; Siesser, W.G. )

    1990-04-01

    Chitinozoans are an extinct group of organic microfossils of uncertain biological affinity. In shape, they resemble minute (50{mu}m-2,000{mu}m) flasks and vases. Chitinozoan fossils occur in marine sedimentary rocks ranging from Cambrian to Carboniferous in age. Chitinozoan diversity is low in the Ridley and Pierce Limestones. Thirteen taxa were identified; two were left in open nomenclature, and one (Conochitina ridleyensis) is provisionally considered to be a new species. Low chitinozoan abundance and the sporadic distribution of chitinozoans in the Ridley and Pierce Limestones is believed to be the result of variable environmental conditions associated with a marine, shallow-shelf environment. The short-ranging chitinozoan taxa Lagenochitina baltica, Conochitina robusta, and Rhabdochitina turgida allow an accurate age assignment to be made for the Ridley and Pierce Limestones. These formations can now be correlated with the Conochitina hirsuta-Lagenochitina sp. A biozone, indicating an upper Blackriveran (mid-Caradocian) age assignment.

  10. Applications of bacterial carbonatogenesis to the protection and regeneration of limestones in buildings and historic patrimony

    NASA Astrophysics Data System (ADS)

    Le Métayer-Levrel, G.; Castanier, S.; Orial, G.; Loubière, J.-F.; Perthuisot, J.-P.

    1999-07-01

    The ability of the so-called carbonatogenic bacteria may be used for producing surficial protecting coatings (biocalcin) on limestones buildings, monuments and statuary. This is the concept of biomineralisation. Laboratory experiments were undertaken in order to choose the most active bacterial strains and to improve the composition of the nutritional media suitable for stimulating the nitrogen cycle metabolic pathways which are the only ones to be used in aerobic and/or microaerophilic conditions. Life-size experiments, subsequent measurements, and observations show that this natural process of biomineralisation is feasible within the frame of industrial constraints. This concept of further developments includes the creation of patinas and the manufacturing of biological mortars and cements which were also improved in the laboratory. The biomineralisation recreates a material that is remarkably similar to the limestone substrate because it uses natural microbial mediation which follows the same natural processes that formed many limestones.

  11. Reduction of soil pollution by usingwaste of the limestone in the cement industry

    NASA Astrophysics Data System (ADS)

    Muñoz, M. Cecilia Soto; Robles Castillo, Marcelo; Blanco Fernandez, David; Diaz Gonzalez, Marcos; Naranjo Lamilla, Pedro; Moore Undurraga, Fernando; Pardo Fabregat, Francisco; Vidal, Manuel Miguel Jordan; Bech, Jaume; Roca, Nuria

    2016-04-01

    In the cement manufacturing process (wet) a residue is generated in the flotation process. This builds up causing contamination of soil, groundwater and agricultural land unusable type. In this study to reduce soil and water pollution 10% of the dose of cement was replaced by waste of origin limestone. Concretes were produced with 3 doses of cement and mechanical strengths of each type of concrete to 7, 28 and 90 days were determined. the results indicate that the characteristics of calcareous residue can replace up to 10% of the dose of cement without significant decreases in strength occurs. It is noted that use of the residue reduces the initial resistance, so that the dose of cement should not be less than 200 kg of cement per m3. The results allow recommends the use of limestone waste since it has been observed decrease in soil and water contamination without prejudice construction material Keywords: Soil contamination; Limestone residue; Adding concrete

  12. Prediction of Building Limestone Physical and Mechanical Properties by Means of Ultrasonic P-Wave Velocity

    PubMed Central

    Concu, Giovanna; De Nicolo, Barbara; Valdes, Monica

    2014-01-01

    The aim of this study was to evaluate ultrasonic P-wave velocity as a feature for predicting some physical and mechanical properties that describe the behavior of local building limestone. To this end, both ultrasonic testing and compressive tests were carried out on several limestone specimens and statistical correlation between ultrasonic velocity and density, compressive strength, and modulus of elasticity was studied. The effectiveness of ultrasonic velocity was evaluated by regression, with the aim of observing the coefficient of determination r2 between ultrasonic velocity and the aforementioned parameters, and the mathematical expressions of the correlations were found and discussed. The strong relations that were established between ultrasonic velocity and limestone properties indicate that these parameters can be reasonably estimated by means of this nondestructive parameter. This may be of great value in a preliminary phase of the diagnosis and inspection of stone masonry conditions, especially when the possibility of sampling material cores is reduced. PMID:24511286

  13. Epilithic and endolithic bacterial communities in limestone from a Maya archaeological site.

    PubMed

    McNamara, Christopher J; Perry, Thomas D; Bearce, Kristen A; Hernandez-Duque, Guillermo; Mitchell, Ralph

    2006-01-01

    Biodeterioration of archaeological sites and historic buildings is a major concern for conservators, archaeologists, and scientists involved in preservation of the world's cultural heritage. The Maya archaeological sites in southern Mexico, some of the most important cultural artifacts in the Western Hemisphere, are constructed of limestone. High temperature and humidity have resulted in substantial microbial growth on stone surfaces at many of the sites. Despite the porous nature of limestone and the common occurrence of endolithic microorganisms in many habitats, little is known about the microbial flora living inside the stone. We found a large endolithic bacterial community in limestone from the interior of the Maya archaeological site Ek' Balam. Analysis of 16S rDNA clones demonstrated disparate communities (endolithic: >80% Actinobacteria, Acidobacteria, and Low GC Firmicutes; epilithic: >50% Proteobacteria). The presence of differing epilithic and endolithic bacterial communities may be a significant factor for conservation of stone cultural heritage materials and quantitative prediction of carbonate weathering. PMID:16391878

  14. 'Dora' & Kids at Day of Play

    NASA Technical Reports Server (NTRS)

    2005-01-01

    From left, Cobie Smith, 5, and Tatume Smith, also 5, have their picture taken with 'Dora the Explorer.' The children were participants in Nickelodeon's Worldwide Day of Play celebration at Stennis Space Center (SSC) on Oct. 1. The Worldwide Day of Play is sponsored annually by Nickelodeon television network to encourage children to be physically active. Approximately 150 children participated in the event at SSC.

  15. Lacustrine sedimentation and origin of the Upper Pennsylvanian Redstone limestone, northern Appalachian basin

    SciTech Connect

    Eggleston, J.R. )

    1993-03-01

    The Redstone limestone occurs in a 7- to 12-m interval between the underlying Pittsburgh and overlying Redstone coal beds. The thickness of the Redstone limestone, which is up to 12 m, varies laterally. The Redstone is sometimes partially or totally replaced by a fluvial siliciclastic unit, which formed either penecontemporaneous or just prior to the limestone. Two cores and an outcrop of Redstone limestone in northern West Virginia were studied in detail. X-ray mineralogical analyses indicate that the limestone is predominantly calcite, ankerite, and quartz, with minor amounts of dolomite, chert, pyrite, feldspar, and clay minerals. Six carbonate facies were identified. The predominant facies is a pedogenic breccia facies that contains typical paleosol features, such as peds and root traces, and represents periods of subaerial exposure of the sediment. A fossiliferous facies contains an abundance of ostracod and mollusk fossilized shells; nested ostracod shells and the occurrence of a shallow-water gastropod, Anthracopupa sp., suggest a shallow-water origin. A bioturbated facies exhibits disrupted bedding and burrows filled with detrital material. The micritic facies contains predominantly calcite and ankerite grains less than 30 microns in diameter and exhibits no apparent bedding. A laminated facies is characterized by two distinct types of lamination: one type is created by interbedding of quartz, clay minerals, plant material, and calcite and/or ankerite and could be caused by periodic storms; the other type contains interbeds of rhombohedral ankerite within predominantly micritic calcite, which could be caused by changes in climate or lake conditions. In summary, petrographic and sedimentological analyses indicate that the Redstone limestone probably formed in a shallow, widespread lake or series of lakes.

  16. Canada's east coast play

    SciTech Connect

    Doig, I.M.

    1984-02-01

    The intent of this paper is to give a basic overview presentation on Canada's east coast play - most likely the number one offshore play in the free world - and possibly the world. The play stretches 2,500 miles north and south, as it follows the Labrador Coast, past the Strait of Belle Isle and onto the Grand Banks of Newfoundland and as it makes a 90 degree turn, 1,000 miles east to west along the coast of Nova Scotia to the Georges Bank. 3,500 miles in all - which if placed in western Canada, would stretch from northern Alberta to southern Mexico. It's geologic potential is immense - 15-20 billion barrels of oil and 80-90 Tcf of natural gas. And so far only approximately 2 billion barrels of oil and 5 Tcf of natural gas have been found. There is more out there. And less than 200 wells have been drilled - still very virgin territory. Two world size discoveries have been made in the area. Hibernia, on the Grand Banks, is estimated to contain 1.8 billion barrels. Venture, on the Scotian Shelf, has a natural gas reserve of 2.5 Tcf - big by Canadian standards and significant in that Mobil Oil has also made some other interesting discoveries on the same Sable Island block which have not been delineated.

  17. Joints and Mineral Veins in Limestone-Marl Alternations: Arrest and Fracture Frequencies

    NASA Astrophysics Data System (ADS)

    Philipp, S. L.; Reyer, D.

    2009-05-01

    Layering is a common feature of many rock masses. In particular, many sedimentary rocks are layered because of depositional changes (stratification), and diagenetic processes. Mechanical layering, where the mechanical properties, particularly the Young's moduli (stiffness), change between layers, may coincide with changes in grain size, mineral content or facies. The mechanical layering of the rock is important because layering commonly results in abrupt changes in local stress fields that may lead to fracture arrest. However, if all the beds in a rock mass have essentially the same Young's modulus and their contacts are welded together (sealed or healed) the beds may function mechanically as a single layer. Here we explore how mechanical layers relate to sedimentary layers in limestone-marl alternations. This we do by investigating the effects of sedimentary layering of the host rock, on the emplacement and geometries of extension fractures such as joints and mineral veins. Detailed field studies were carried out at two localities of well-exposed limestone-marl alternations: (1) the Jurassic Blue Lias at the Glamorgan Coast of South Wales, UK, and (2) the Triassic Muschelkalk in the Kraichgau area, Southwest Germany. In both study areas, calcite veins occur almost exclusively in the cores and damage zones of faults, whereas jointing is pervasive. Fracture arrest, common in mechanically layered host rocks, is primarily controlled by local variations in the stress field, mainly due to three factors: discontinuities (fractures and contacts), changes in host rock mechanical properties, and stress barriers, where the local stress field is unfavorable to fracture propagation. These factors are related in that changes in stiffness and stress barriers are common at contacts between different rock types. A fourth mechanism, namely the material toughness (critical strain energy release rate) of the contact in relation to that of the adjacent layers has been much studied in

  18. Rapid method to determine actinides and 89/90Sr in limestone and marble samples

    DOE PAGES

    Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.; Utsey, Robin C.; Sudowe, Ralf; McAlister, Daniel R.

    2016-04-12

    A new method for the determination of actinides and radiostrontium in limestone and marble samples has been developed that utilizes a rapid sodium hydroxide fusion to digest the sample. Following rapid pre-concentration steps to remove sample matrix interferences, the actinides and 89/90Sr are separated using extraction chromatographic resins and measured radiometrically. The advantages of sodium hydroxide fusion versus other fusion techniques will be discussed. Lastly, this approach has a sample preparation time for limestone and marble samples of <4 hours.

  19. Passive treatment of acid mine drainage in down-flow limestone systems

    SciTech Connect

    Watzlaf, G.R.

    1997-12-31

    Passive down-flow systems, consisting of compost and/or limestone layers, may be well suited for treatment of acidic mine drainage containing ferric iron and/or aluminum. Two columns were constructed and operated in the laboratory. The first column simulated a downward, vertical-flow anaerobic wetland, also referred to as successive alkalinity-producing systems (SAPS), and has received mine drainage for 97 weeks. The 0.16-m diameter column was vertically oriented and (from bottom to top) consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost, and 0.91 m of free standing water. Water flowed vertically downward through the system. A second column, filled with only limestone, received water from the same source as the first column. This limestone column contained a 1.06-m thick layer of limestone and 0.91 m of free standing water and has received water for 55 weeks. Actual acid mine drainage (pH = 3.1, acidity = 200 mg/L (as CaCO{sub 3}), SO{sub 4}{sup 2-} = 600 mg/L, Total Fe = 10 mg/L, Mn = 14 mg/L, and Al = 18 mg/L) was collected every two weeks from a nearby abandoned deep mine and applied to these columns at a rate of 3.8 mL/min. For the compost/limestone column, effluent pH remained above 6.2 (6.2-7.9); however, pH at a depth of 0.38 m in the compost (halfway) dropped to < 4 after 28 weeks (net acidic). At the bottom of the compost pH remained > 4.5 for all 97 weeks. Alkalinity was generated by a combination of limestone dissolution and sulfate reduction. Over the 97 week period, the column generated an average of 330 mg/L of alkalinity, mostly due to limestone dissolution. Bacterial sulfate reduction displayed an ever decreasing trend, initially accounting for more than 200 mg/L of alkalinity and after 40 weeks only accounting for about 50 mg/L.

  20. Accelerated weathering of limestone for CO2 mitigation: Opportunities for the stone and cement industries

    USGS Publications Warehouse

    Langer, William H.; San, Juan A.; Rau, Greg H.; Caldeira, Ken

    2009-01-01

    Accelerated weathering of limestone appears to provide a low-tech, inexpensive, high-capacity, environmentally friendly CO2 mitigation method that could be applied to about 200 fossil fuel fired power plants and about eight cement plants located in coastal areas in the conterminous U.S. This approach could also help solve the problem of disposal of limestone waste fines in the crushed stone industry. Research and implementation of this technology will require new collaborative efforts among the crushed stone and cement industries, electric utilities, and the science and engineering communities.

  1. Discrimination of moist oil shale and limestone using laser induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Paris, P.; Piip, K.; Lepp, A.; Lissovski, A.; Aints, M.; Laan, M.

    2015-05-01

    Laser-induced plasma emission spectra of Estonian oil shale and associated limestone with varying moisture content were studied. Time gated spectra excited by 1064 nm laser radiation were recorded. Spectral lines for determination of plasma parameters were selected. Moisture causes the reduction of the intensity of the total emission, and increases the intensity of the Hα line. It was found that the effect of the moisture content on the plasma temperature and electron concentration was inconsiderable. Using the ratio of intensities of Hα and Mg spectral lines, it was possible to distinguish reliably between limestone and oil shale independently of their moisture content.

  2. Basalt-Limestone and Andesite-Limestone Interaction in the Arc Crust - Implications for Volcanic Degassing of CO2

    NASA Astrophysics Data System (ADS)

    Carter, L. B.; Dasgupta, R.

    2014-12-01

    Volcanically emitted CO2 is generally mantle-derived, but high degassing rates at some arcs (e.g. Merapi [1] and Colli Albani Volcanic District [2]) are thought to be affected by magma-carbonate interaction in the upper plate. However, the effects of depth, temperature, and composition on this process are poorly known. We experimentally simulated magma (50%)-limestone (50%) wallrock interactions at 0.5-1.0 GPa, 1100-1200 °C using pure calcite and a hydrous (~3-5 wt.% H2O) melt (basalt, andesite, or dacite). At 1.0 GPa, 1200 °C starting melts are superliquidus, whereas in the presence of calcite, Ca-rich cpx ± Ca-scapolite are produced. With increasing T, basalt-calcite interaction causes the melt, on a volatile-free basis, to become silica-poor and Ca-rich with alumina decreasing as cpx becomes more CaTs-rich. The same trend is seen with all starting melt compositions as P decreases at a constant T (1200 °C), producing melts similar to ultracalcic (CaO/Al2O3>>1) melt inclusions found in arc settings. Shifting from basalt to andesite has little effect on SiO2 and CaO of the reacted melt (e.g. 37 wt.% SiO2, 42 wt.% CaO at 0.5 GPa, 1200 °C), whereas Al2O3 of andesite-derived reacted melt is lower, likely a result of lower alumina in the starting andesite. Wall-rock calcite consumption is observed to increase with increasing T, decreasing P, and increasing melt XSiO2. At 0.5 GPa between 1100 and 1200 °C, our basalt experiments yield carbonate assimilation from 22 to 48 wt.%. This decreases to 20 wt.% at 1.0 GPa, 1200 °C, whereas an andesitic composition assimilates 59 to 52 wt.% from 0.5 to 1.0 GPa at 1200 °C. The higher assimilation in andesite-added runs at high-T is because of lower silicate liquidus as evidenced by lower modal proportion or absence of cpx ± scapolite. Using a magma flux rate estimated for Mt. Vesuvius [3], we obtain a CO2 outflux for a single such volcano experiencing arc magma-calcite reaction [4] of at least 2-4% of the present

  3. Exploration potential of Albania

    SciTech Connect

    Silverman, M.R. )

    1991-08-01

    Albania is rich in natural resources, especially crude oil and natural gas. It has far greater petroleum reserves for its size than any other country in Eastern Europe. The nation consists of three principal geologic provinces. Strongly folded upper Paleozoic and Mesozoic strata comprise the Sub-Pelagonian and Pelagonian massifs in the northeast Albania. The search for oil and gas in the future is likely to be concentrated in the coastal basins and offshore in the relatively shallow waters of the Adriatic Sea. Hydrocarbons have been trapped onshore in anticlines and tilted fault blocks, primarily in lenticular upper Miocene sandstones and in Helvetian limestones. Exploration for stratigraphic and other nonstructural traps may represent the best potential for future discoveries onshore. Albania's greatest oil and gas potential is probably in the Albanian shelf of the Durres basin, offshore. No wells have ever been drilled offshore, and exploration is confined to a limited, nearshore seismic survey. Recent access to Albanian data suggests most published regional interpretations are many years out of date. Albania's offshore potential includes several zones of hydrocarbon generation in Mesozoic to Paleogene strata. Potential reservoirs include Neogene flysch sandstones and Mesozoic platform carbonates. Albania has recently invited foreign oil companies to apply for offshore exploration rights. As Albania is opened to foreign investment in the petroleum sector, there is little doubt that modern seismic techniques and the deliberate search for subtle traps may be expected to lead to substantial new discoveries.

  4. Play in Practice: Case Studies in Young Children's Play.

    ERIC Educational Resources Information Center

    Brown, Cheryl Render, Ed.; Marchant, Catherine, Ed.

    This book uses a collection of stories, or "cases," as a basis for reflection, discussion, and learning about the many roles "play" has in children's lives. Each of the 12 cases addresses an issue of play from one of three categories--the role of adults in play, the cultural meanings of play, and the issues related to play in special settings.…

  5. Exploring Children's Perceptions of Play Using Visual Methodologies

    ERIC Educational Resources Information Center

    Anthamatten, Peter; Wee, Bryan Shao-Chang; Korris, Erin

    2013-01-01

    Objective: A great deal of scholarly work has examined the way that physical, social and cultural environments relate to children's health behaviour, particularly with respect to diet and exercise. While this work is critical, little research attempts to incorporate the views and perspectives of children themselves using visual methodologies.…

  6. Playing with Pitch: Exploring and Investigating the Science of Sound

    ERIC Educational Resources Information Center

    Mueller, Andrea; Clair, Jan Le; Kechaidis, Maria; Swain, Wendy; MacDonald, Jane

    2004-01-01

    This activity is the result of a school-university collaboration among four educators (two intermediate classroom teachers, a vice-principal/teacher, and a university-based teacher educator/researcher) who worked together to improve the quality of learning in the classroom. The educators combined their teaching expertise to plan and co-teach an…

  7. Triple Play: Three Educators Explore Education and Economic Development.

    ERIC Educational Resources Information Center

    O'Neil, Robert M.; And Others

    1984-01-01

    Discusses the ways in which the University of Wisconsin system, the Wisconsin Board of Vocational, Technical and Adult Education, and the Department of Public Instruction contribute to the economic development of the state. (JOW)

  8. Recovery and recycling of limestone in LEC flue gas desulfurization. Final report, June 1, 1990--August 31, 1991

    SciTech Connect

    Gardner, N.C.; Adler, R.J.; Lin, Y.C.; Unger, M.E.; Lux, K.W.

    1992-03-01

    Prudich et al. have proposed an attractive technology called Limestone Emission Control (LEC) for removing sulfur dioxide from flue gases. Beds of 1/8 inch wet limestone particles absorb the sulfur dioxide from the gases. Sulfates and sulfites deposit on the surfaces of the particles, limiting their utilization to about 20%. The unreacted portion of the limestone can be recovered by mechanical grinding and recycling, enabling high overall sorbent utilization. Favorable economic costs derive from small equipment, simplicity, and low sorbent cost. Our research concentrates on selecting and testing on a laboratory scale suitable candidate dry and wet grinding methods for recovering limestone in LEC flue from desulfurization. A wet grinding method based on the impeller fluidizer, a new type of slurry processor, receives special attention. The impeller fluidizer is a dosed cylindrical vessel with an impeller at one end. It combines the operations of wet grinding, washing, and transporting the spent and recovered limestone as an aqueous slurry.

  9. When play is a family business: adult play, hierarchy, and possible stress reduction in common marmosets.

    PubMed

    Norscia, Ivan; Palagi, Elisabetta

    2011-04-01

    Easy to recognize but not easy to define, animal play is a baffling behavior because it has no obvious immediate benefits for the performers. However, the absence of immediate advantages, if true, would leave adult play (costly but maintained by evolution, spanning lemurs to Homo sapiens) unexplained. Although a commonly held view maintains that play is limited by stress, an emergent hypothesis states that play can regulate stress in the short term. Here we explored this hypothesis in a captive family group of New World monkeys, Callithrix jacchus (common marmoset). We observed six subjects and gathered data on aggressive, play, and scratching behavior via focal (6 h/individual) and all occurrences sampling (115 h). We found that play levels were highest during pre-feeding, the period of maximum anxiety due to the forthcoming competition over food. Scratching (the most reliable indicator of stress in primates) and play showed opposite trends along hierarchy, with dominants scratching more and playing less than subordinates. Finally, scratching decreased after play, whereas play appeared to be unrelated to previous scratching events, symptoms of a potential stressful state. In conclusion, both play timing and hierarchical distribution indicate that play limits stress, more than vice versa, at least in the short term. PMID:21107884

  10. When play is a family business: adult play, hierarchy, and possible stress reduction in common marmosets.

    PubMed

    Norscia, Ivan; Palagi, Elisabetta

    2011-04-01

    Easy to recognize but not easy to define, animal play is a baffling behavior because it has no obvious immediate benefits for the performers. However, the absence of immediate advantages, if true, would leave adult play (costly but maintained by evolution, spanning lemurs to Homo sapiens) unexplained. Although a commonly held view maintains that play is limited by stress, an emergent hypothesis states that play can regulate stress in the short term. Here we explored this hypothesis in a captive family group of New World monkeys, Callithrix jacchus (common marmoset). We observed six subjects and gathered data on aggressive, play, and scratching behavior via focal (6 h/individual) and all occurrences sampling (115 h). We found that play levels were highest during pre-feeding, the period of maximum anxiety due to the forthcoming competition over food. Scratching (the most reliable indicator of stress in primates) and play showed opposite trends along hierarchy, with dominants scratching more and playing less than subordinates. Finally, scratching decreased after play, whereas play appeared to be unrelated to previous scratching events, symptoms of a potential stressful state. In conclusion, both play timing and hierarchical distribution indicate that play limits stress, more than vice versa, at least in the short term.

  11. Problem Solvers: Solutions--Playing Basketball

    ERIC Educational Resources Information Center

    Smith, Jeffrey

    2014-01-01

    In this article, fourth grade Upper Allen Elementary School (Mechanicsburg, Pennsylvania) teacher Jeffrey Smith describes his exploration of the Playing Basketball activity. Herein he describes how he found the problem to be an effective way to review concepts associated with the measurement of elapsed time with his students. Additionally, it…

  12. Children's Thinking Styles, Play, and Academic Performance

    ERIC Educational Resources Information Center

    Holmes, Robyn M.; Liden, Sharon; Shin, Lisa

    2013-01-01

    Based on the study of seventy-four middle school children of mostly Filipino and part Hawaiian heritages, this article explores the relationships of children's thinking styles, play preferences, and school performance. Using the Group Embedded Figures Test, the Articulation of the Body Scale, and written responses to three questions, the authors…

  13. Children's Spontaneous Vocalisations during Play: Aesthetic Dimensions

    ERIC Educational Resources Information Center

    Countryman, June; Gabriel, Martha; Thompson, Katherine

    2016-01-01

    This paper explores the phenomenon of spontaneous vocalisations in the self-chosen, unstructured outdoor play of children aged 3-12. Spontaneous vocalisations encompass the whole range of children's unprompted, natural, expressive vocal soundings beyond spoken language. Non-participant observations at childcare centres and on elementary school…

  14. Gender, Play, Language, and Creativity in Preschoolers

    ERIC Educational Resources Information Center

    Holmes, Robyn M.; Romeo, Lynn

    2013-01-01

    This study explored the effects of a child's gender and school setting on preschoolers' language abilities (receptive vocabulary), creativity, and social play. The participants were primarily European-American children who spoke English as a primary language (nine children were bilingual), and were from middle income socioeconomic…

  15. Microblogging Activities: Language Play and Tool Transformation

    ERIC Educational Resources Information Center

    Hattem, David

    2014-01-01

    The following is a qualitative case study presenting three vignettes exploring the use of language play while microblogging during an academically sanctioned task. Ten students and one teacher used "Twitter" in an intensive, English as a second language advanced grammar course to practice writing sentences with complex grammatical…

  16. Adults and Children Developing Play Together.

    ERIC Educational Resources Information Center

    Bruce, Tina

    1997-01-01

    Identifies four dominant strands in the recent literature on adults and children developing play together: socio-cultural, adversarial, child development, and nomad-academic. Explores each strand and analyzes areas of agreement and disagreement to see if any reconciliations can be made across differences. Asserts that each strand is important in…

  17. World History Plays, Puzzles and Activities.

    ERIC Educational Resources Information Center

    Stevens, Lawrence

    This instructional resource, for grades 7-10, includes a collection of 10 plays with related learning activities. Units of study include: (1) "Alexander the Great and the Greeks"; (2) "The Black Death and the End of the Middle Ages"; (3) "Robert Clive and Imperialism"; (4) "Christopher Columbus and the Age of Exploration"; (5) "Fall of the…

  18. Serious Design for Serious Play in Physics.

    ERIC Educational Resources Information Center

    Rieber, Lloyd P.; Matzko, Michael J.

    2001-01-01

    These designers approaches their physics lesson design task from the viewpoint of play. The designs, all having strong gaming influences, aim to be flexible enough to take advantage of the experience and ideas of a teacher working with a standard curriculum, yet interesting enough for students to want to continue exploring resources on their own…

  19. Development through Work and Play.

    ERIC Educational Resources Information Center

    Hartung, Paul J.

    2002-01-01

    Five proposals are made for incorporating a work-play perspective in career development research: (1) fuse work and play conceptually over the life course; (2) imbue developmental career theory with a work-play fusion; (3) study work and play across the life span; (4) investigate work and play within the life space; and (5) consider a work-play…

  20. The Neglected Factor-Play

    ERIC Educational Resources Information Center

    Feitelson, Dina; Ross, Gail S.

    1973-01-01

    Spontaneous thematic play behavior in children is investigated. Environmental prerequisites of play and possible functions of play in cognitive and personality development are discussed. Whether modelling is a prerequisite for thematic play, and the relationship between level of play and creativity test performance in children are assessed. (DP)

  1. Oxygen and carbon isotopic composition of limestones and dolomites, bikini and eniwetok atolls.

    PubMed

    Gross, M G; Tracey, J I

    1966-03-01

    Aragonitic, unconsolidated sediments from the borings on the Eniwetok and Bikini atolls are isotopically identical with unaltered skeletal fragments, whereas the recrystallized limestones exhibit isotopic variations resulting from alteration in meteoric waters during periods of emergence. Dolomites and associated calcites are enriched in O(18), perhaps because of interaction with hypersaline brines.

  2. Unconformity-associated replacement limestones after anhydrite in Mississippian of Williston Basin

    SciTech Connect

    Kendall, A.C.

    1983-03-01

    Locally in southeastern Saskatchewan, Mississippian nodular anhydrites (after subaqueous gypsum) beneath an unconformity have been altered to limestone-limestones that are commonly porous and oil-bearing. In the region, carbonates beneath the unconformity are normally overlain by red beds and have been completely dolomitized and plugged with anhydrite to form an impermeable caprock. Mississippian anhydrites subcrop at the unconformity surface and reveal little evidence of alteration-even to gypsum. Textures in replaced anhydrites indicate that calcitization involved both creation of porosity and in-situ (small-scale) replacement leading to retention of anhydrite (and later gypsum) fabrics. Celestite formed as strontium was released from anhydrite during replacement by gypsum and calcite. Sulfur in associated pyrite is isotopically lighter than the anhydrite, suggesting anhydrite-alteration involved the activities of sulfate-reducing bacteria. Evidently, H/sub 2/S liberated during the reaction migrated across the unconformity to reduce overlying red beds. Limestones of this type do not appear to have been reported previously. Stratigraphic and petrographic evidence indicates replacement, although spacially related to the unconformity, was not a weathering phenomenon. It occurred after the unconformity was buried. Unexpectedly heavy delta/sup 13/C and delta/sup 18/O values (+ 1.22 to 1.54, and -1.0 to -3.7) obtained from the replacement limestones seem to preclude the utilization of organic carbon in the reaction. The source of carbonate and of the energy required for sulfate-reducing bacterial activity is therefore problematic.

  3. Lead, zinc, and strontium in limestone cap rock from Tatum salt dome, Mississippi

    SciTech Connect

    Saunders, J.A.

    1988-09-01

    Limestone cap rock at Tatum salt dome, Mississippi, contains disseminated pyrite, sphalerite, and galena, and disseminated to massive amounts of strontianite (SrCO/sub 3/) and celestite (SrSO/sub 4/). Sulfide minerals are locally present in bitumen-rich areas of the upper, massive portion of the limestone cap rock, whereas strontium minerals are disseminated throughout this zone. However, sulfide and strontium minerals are most abundant in the lower banded portion of the limestone cap rock, which consists of alternating subhorizontal light and dark-colored bands. The dark bands are composed of calcite of variable grain size, sulfides, quartz, dolomite, albite, and up to 1% bitumen that apparently formed by the biodegradation of crude oil. Lighter bands are composed of variable amounts of coarsely crystalline, euhedral calcite, strontianite, and celestite resulting in strontium (Sr) contents of up to 30% locally. Banded limestone cap rock at Tatum dome formed at the top of the actively dissolving anhydrite zone by a combination of sulfate reduction and oxidation of liquid hydrocarbons by bacteria to cause the precipitation of calcite and sulfide minerals and the accumulation of insoluble residue from the anhydrite (quartz, albite, dolomite). Lead and zinc in the sulfide minerals could have been derived from the dissolving anhydrite, but the abundance of Sr minerals present requires an external source. Present-day oil field brines in central Mississippi contain up to 3000 ppm Sr, and basin brines of similar composition apparently contributed Sr to the cap-rock environment during formation.

  4. The effect of elevated temperature on the strength parameters of silica acid ester consolidated porous limestones

    NASA Astrophysics Data System (ADS)

    Pápay, Zita; Török, Ákos

    2013-04-01

    The porous limestone is one of the most widespread construction materials of the monuments in Central Europe, with emblematic buildings in Vienna, Bratislava, Budapest and many other cities of Austria, Slovakia, Czech Republic and Hungary. The restoration of these monuments very often requires the consolidation of the porous limestone material, where various types of consolidants are used to strengthen the highly weathered stone. Our research focused on the understanding of the behaviour of consolidated porous limestone when the material is subjected to higher temperatures. Test procedure included the preparation of cylindrical test specimens from the Miocene porous limestone which was followed by consolidation by four various types of silica acid ester. The samples after consolidation were heated to 300 and 600 °C in electric oven. The material properties such as ultrasonic pulse velocity, density were tested before and after the treatment. Indirect tensile strength (Brazilian test) was used to compare the strength parameters of non treated and consolidated samples. Silica acid ester treated samples after heating were also measured in terms of strength, density and ultrasonic pulse velocity. The results show that there are significant changes in strength of various pre-treated samples after heating indicating the sensitivity of the materials to temperature changes and accidental fire.

  5. Hydrogen sulfide capture by limestone and dolomite at elevated pressure. 2: Sorbent particle conversion modeling

    SciTech Connect

    Zevenhoven, C.A.P.; Yrjas, K.P.; Hupa, M.M.

    1996-03-01

    The physical structure of a limestone or dolomite to be used in in-bed sulfur capture in fluidized bed gasifiers has a great impact on the efficiency of sulfur capture and sorbent use. In this study an unreacted shrinking core model with variable effective diffusivity is applied to sulfidation test data from a pressurized thermogravimetric apparatus (P-TGA) for a set of physically and chemically different limestone and dolomite samples. The particle size was 250--300 {micro}m for all sorbents, which were characterized by chemical composition analysis, particle density measurement, mercury porosimetry, and BET internal surface measurement. Tests were done under typical conditions for a pressurized fluidized-bed gasifier, i.e., 20% CO{sub 2}, 950 C, 20 bar. At these conditions the limestone remains uncalcined, while the dolomite is half-calcined. Additional tests were done at low CO{sub 2} partial pressures, yielding calcined limestone and fully calcined dolomite. The generalized model allows for determination of values for the initial reaction rate and product layer diffusivity.

  6. Performance Monitoring: Evaluating an Organic Carbon-Limestone PRB for Treatment of Heavy Metals and Acidity

    EPA Science Inventory

    Since 2004, researchers from the U.S. EPA National Risk Management Research Laboratory (NRMRL) have annually evaluated performance of an organic carbon-limestone permeable reactive barrier (PRB) system installed in 2003 by EPA Region 6 at the Delatte Metals Superfund site in Ponc...

  7. Limestone characterization to model damage from acidic precipitation: Effect of pore structure on mass transfer

    USGS Publications Warehouse

    Leith, S.D.; Reddy, M.M.; Irez, W.F.; Heymans, M.J.

    1996-01-01

    The pore structure of Salem limestone is investigated, and conclusions regarding the effect of the pore geometry on modeling moisture and contaminant transport are discussed based on thin section petrography, scanning electron microscopy, mercury intrusion porosimetry, and nitrogen adsorption analyses. These investigations are compared to and shown to compliment permeability and capillary pressure measurements for this common building stone. Salem limestone exhibits a bimodal pore size distribution in which the larger pores provide routes for convective mass transfer of contaminants into the material and the smaller pores lead to high surface area adsorption and reaction sites. Relative permeability and capillary pressure measurements of the air/water system indicate that Salem limestone exhibits high capillarity end low effective permeability to water. Based on stone characterization, aqueous diffusion and convection are believed to be the primary transport mechanisms for pollutants in this stone. The extent of contaminant accumulation in the stone depends on the mechanism of partitioning between the aqueous and solid phases. The described characterization techniques and modeling approach can be applied to many systems of interest such as acidic damage to limestone, mass transfer of contaminants in concrete and other porous building materials, and modeling pollutant transport in subsurface moisture zones.

  8. Goat Urine and Limestone Affect Nitrogen and Cation Distributions in an Acidic Grassland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of goats (Capra aegagrus hircus L.) to clear overgrown pastures and woodlots of unwanted vegetation may result in high rates of urine deposition where goats congregate. Surface application of limestone to dystrophic acid soils before clearing is known to augment ammonia gas volatilization from ...

  9. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation

    EPA Science Inventory

    The U.S. Geological Survey - Leetown Science Center and the Colorado School of Mines have developed a remediation process for the treatment of metals in circumneutral mining influenced waters. The process involves treatment with a pulsed limestone bed (PLB) system, followed by c...

  10. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation (Presentation)

    EPA Science Inventory

    The U.S. Geological Survey - Leetown Science Center and the Colorado School of Mines have developed a remediation process for the treatment of metals in circumneutral mining influenced waters. The process involves treatment with a pulsed limestone bed (PLB) system, followed by c...

  11. Hydrology of the cavernous limestones of the Mammoth Cave area, Kentucky

    USGS Publications Warehouse

    Brown, Richmond F.

    1966-01-01

    The Mammoth Cave National Park in central Kentucky offers a unique opportunity to study the occurrence of ground water in limestone under natural conditions. Ground water occurs as perched and semiperched bodies in alternate sandstone, shale, and limestone formations and under water-table conditions at the approximate level of the Green River in thick soluble limestone. Three continuous recorders that operated for 5 years indicate that precipitation on the Mammoth Cave plateau recharges the underlying sandstone rapidly. Ground water from the sandstone discharges horizontally to the edges of the plateau and vertically to underlying formations. Some of the precipitation recharges underlying formations almost immediately through overland flow to sinkholes and free fall through open shafts to pools at the water table. Much of the precipitation on the Pennyroyal plain flows overland into sinkholes and then through solution openings to the Green River. Water from the Green River flows into limestone solution channels under Mammoth Cave plateau at some stages, and this water discharges again to the Green River downstream. The presence of salt water, high in chloride in the Green River, makes it possible to trace the movement of the river water through the underground streams. Graphs show relationships of chloride concentration, stage of the Green River, time, precipitation, ground-water levels, and stratigraphy.

  12. Assessment of radiological hazard of NORM in Margalla Hills limestone, Pakistan.

    PubMed

    Ali, Muhammad; Qureshi, Aziz Ahmed; Waheed, Abdul; Baloch, Muzahir Ali; Qayyum, Hamza; Tufail, Muhammad; Khan, Hameed Ahmed

    2012-08-01

    Studies on naturally occurring radioactive material (NORM) in the limestone from the Margalla Hills have been carried out by measuring gamma activity and to access its radiological implications if any. For data acquisition, a High-Purity Germanium detector was employed. The activity concentrations of (226)Ra, (232)Th, and (40)K were found to be 14.32 ± 0.24, 2.05 ± 0.04, and 13.80 ± 0.20 Bq kg(-1), respectively. These values are relatively lower as compared to that in the limestone of other countries and much lower than the values reported for the natural building stones. The average specific activities due to (226)Ra were found to be higher when compared with (40)K and (232)Th. Indices of radium equivalent activity (Ra(eq)), internal hazard (H(in)), indoor absorbed gamma dose rate (D(R,)), and corresponding annual effective dose (E(eff)) were also determined for the limestone-made rooms. All of these indices were found to be in the lower ranges. The Margalla Hills limestone does not pose any excessive radiological health hazard as a building material and in industrial uses for a common man.

  13. Use of limestone obtained from waste of the mussel cannery industry for the production of mortars

    SciTech Connect

    Ballester, Paloma; Marmol, Isabel; Morales, Julian; Sanchez, Luis . E-mail: luis-sanchez@uco.es

    2007-04-15

    Various types of cement-SiO{sub 2}-CaCO{sub 3} mortar were prepared by replacing quarry limestone aggregate with limestone obtained as a by-product from waste of the mussel cannery industry. The CaCO{sub 3} aggregate consists mainly of elongated prismatic particles less than 4 {mu}m long rather than of the rounded particles of smaller size (2-6 {mu}m) obtained with quarry limestone. The mechanical and structural properties of the mortars were found to be influenced by aggregate morphology. Setting of the different types of mortar after variable curing times was evaluated by scanning electron microscopy (SEM), thermogravimetric analysis (TG) and mercury intrusion porosimetry (MIP) techniques. Mortars with a high content in mussel shell limestone exhibited a more packed microstructure, which facilitates setting of cement and results in improved mortar strength. The enhanced mechanical properties of the new mortars allow the cement content in the final mortar composition to be decreased and production costs to be reduced as a result.

  14. Adsorption/desorption of phosphorus on limestone from the Biscayne Aquifer under freshwater and seawater conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Areas of seawater intrusion are known geochemically active regions particularly in limestone aquifers, where carbonate mineral dissolution and ion exchange reactions are important. Both of these processes can lead to a release of phosphorus from the aquifer matrix to the groundwater as seawater int...

  15. The mechanics of intersecting echelon veins and pressure solution seams in limestone

    NASA Astrophysics Data System (ADS)

    Seyum, Solomon; Pollard, David D.

    2016-08-01

    Many studies that describe the formation of echelon vein arrays relate the causative stresses implicitly to the deformation, reliant on simple shear kinematics, such that the vein-to-array angle and the array width are the primary physical quantities. In contrast, we identify twelve physical quantities to describe echelon veins in two dimensions, including coeval, vein-intersecting, pressure solution seams. A finite element method is used to reproduce vein shapes in linear elastic and elastic-perfectly plastic model limestone. Model vein geometries are designed using values within the range of geometries measured from echelon veins at Raplee Anticline and Comb Monocline, Utah. Four physical quantities are significant for describing echelon vein shapes: vein spacing, vein-array angle, limestone elastic stiffness, and closing of orthogonal pressure solution seams. Pressure solution seam closing influences the mechanical interaction between adjacent veins, and for a range of conditions, causes a nearly linear vein opening distribution (triangular shapes) and encourages straight vein propagation, both of which approximate field measurements. Model results show that small spacing of veins with seams and large vein-array angles promote straight vein traces in limestone with stiffness typical of laboratory measurements, given the physical geologic conditions inferred from the burial history of the limestone strata.

  16. 76 FR 60815 - Final Legislative Environmental Impact Statement (LEIS) for the Limestone Hills Training Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... Department of the Army Final Legislative Environmental Impact Statement (LEIS) for the Limestone Hills Training Area Land Withdrawal, Montana Army National Guard (MTARNG) AGENCY: National Guard Bureau (NGB), Department of the Army, DoD. ACTION: Notice of availability. SUMMARY: This announces the availability of...

  17. Alteration of limestone surfaces in an acid rain environment by gas-solid reaction mechanisms

    SciTech Connect

    Mossotti, V.G.; Lindsay, J.R.; Hochella, M.F. Jr.

    1987-01-01

    As part of a study to assess mineralogical alterations in building stone due to acid rain, Salem Limestone was exposed in the form of briquettes for one year in several urban and one rural environment. Samples exposed in the rural location were found to be chemically indistinguishable from the freshly quarried limestone (control material). In marked contrast, all samples collected from urban exposure sites developed gypsum stains on the ground-facing surfaces where the stones were unwashed by precipitation. However, the bulk chemistry of the urban samples (not including the stain) was virtually identical to the that of the control stone. X-ray photoelectron spectroscopy (XPS) revealed the presence of sulfur (in the form of sulfate) disseminated over the calcite grain surfaces to a depth less than 10 nm in the freshly quarried limestone; XPS showed an identical sulfate layer on the calcite grains after the one year exposure period. Mass balance calculations and sulfur isotope patterns indicate that the gypsum stain on the protected surfaces consists of adventitious sulfur. The authors found no evidence of nitrate attack on any of the limestone surfaces.

  18. Optimization of nanolime solvent for the consolidation of coarse porous limestone

    NASA Astrophysics Data System (ADS)

    Borsoi, Giovanni; Lubelli, Barbara; van Hees, Rob; Veiga, Rosário; Silva, António Santos

    2016-09-01

    The potentialities of nanomaterials for application in the field of conservation have been widely investigated in the last two decades. Among nanomaterials, nanolimes, i.e., dispersions of lime nanoparticles in alcohols are promising consolidating products for calcareous materials. Nanolimes are effective in recovering the very superficial loss of cohesion of decayed materials, but they do not always provide sufficient mass consolidation. This limitation is mainly related to the deposition of the nanoparticles nearby the surface of the material. Experimental research has been set up with the aim of improving the in-depth deposition of lime nanoparticles. Previous research by the authors has shown that nanolime deposition within a substrate can be controlled by adapting the nanolimes properties (kinetic stability and evaporation rate) to the moisture transport behavior of the substrate. Nanolime properties can be modified by the use of different solvents. In this research, nanolime dispersions have been further optimized for application on Maastricht limestone, a coarse porous limestone. Firstly, nanolimes were synthesized and dispersed in ethanol and/or water, both pure and mixed in different percentages. Subsequently, based on the kinetic stability of the nanolime dispersions, the most promising solvent mixtures were selected and applied on the limestone. The deposition of lime nanoparticles within the limestone was studied by phenolphthalein test, optical microscopy and scanning electron microscopy. The results confirm that nanolime dispersed in a mixture of ethanol (95 %) and water (5 %) can guarantee a better nanoparticles in-depth deposition within coarse porous substrates, when compared to dispersions in pure ethanol.

  19. Sulfate Attack of Cement-Based Material with Limestone Filler Exposed to Different Environments

    NASA Astrophysics Data System (ADS)

    Gao, Xiaojian; Ma, Baoguo; Yang, Yingzi; Su, Anshuang

    2008-08-01

    Mortar prisms made with OPC cement plus 30% mass of limestone filler were stored in various sulfate solutions at different temperatures for periods of up to 1 year, the visual appearance was inspected at intervals, and the flexural and compressive strength development with immersion time was measured according to the Chinese standard GB/T17671-1999. Samples were selected from the surface of prisms after 1 year immersion and examined by x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), laser-raman spectroscopy and scanning electron microscopy (SEM). The results show that MgSO4 solution is more aggressive than Na2SO4 solution, and Mg2+ ions reinforce the thaumasite sulfate attack on the limestone filler cement mortars. The increase of solution temperature accelerates both magnesium attack and sulfate attack on the limestone filler cement mortar, and leads to more deleterious products including gypsum, ettringite and brucite formed on the surface of mortars after 1 year storage in sulfate solutions. Thaumasite forms in the mortars containing limestone filler after exposure to sulfate solutions at both 5 °C and 20 °C. It reveals that the thaumasite form of sulfate attack is not limited to low-temperature conditions.

  20. Demonstration of a hydration process for reactivating partially sulfated limestone sorbents

    SciTech Connect

    Smith, G.W.; Hajicek, D.R.; Myles, K.M.; Goblirsch, G.M.; Mowry, R.W.; Teats, F.G.

    1981-10-01

    The utilization of limestione sorbent for the removal of SO/sub 2/ in coal combustion in an atmospheric fluidized-bed combustor (AFBC) can be markedly increased by reactivating the partially sulfated limestone for reuse in the combustor. Such reuse would reduce costs and the environmental impact of quarrying and disposing of large quantities of limestone. The reactivation process consists of hydrating the partially sulfated limestone by treatment with water. A demonstration of the hydration process and the reuse of the reactivated limestone were carried out at Grand Forks Energy Technology Center (GFETC) in cooperation with Argonne National Laboratory (ANL). The data obtained in the GFETC 0.2-m/sup 2/ AFBC are compared with those obtained earlier in the ANL 0.02-m/sup 2/ AFBC. Marked enhancement of calcium utilization was achieved in both studies, but differences were noted in the degree of enhancement and in the Ca/S mole ratios required to maintain SO/sub 2/ in the off-gas at an acceptable level.

  1. Farm Hall: The Play

    NASA Astrophysics Data System (ADS)

    Cassidy, David C.

    2013-03-01

    It's July 1945. Germany is in defeat and the atomic bombs are on their way to Japan. Under the direction of Samuel Goudsmit, the Allies are holding some of the top German nuclear scientists-among them Heisenberg, Hahn, and Gerlach-captive in Farm Hall, an English country manor near Cambridge, England. As secret microphones record their conversations, the scientists are unaware of why they are being held or for how long. Thinking themselves far ahead of the Allies, how will they react to the news of the atomic bombs? How will these famous scientists explain to themselves and to the world their failure to achieve even a chain reaction? How will they come to terms with the horror of the Third Reich, their work for such a regime, and their behavior during that period? This one-act play is based upon the transcripts of their conversations as well as the author's historical work on the subject.

  2. Laboratory studies of Miocene limestone for the use of construction industry in Sri Lanka

    NASA Astrophysics Data System (ADS)

    de Silva Jayawardena, Upali

    2016-04-01

    Geologically ten percent of Sri Lanka is made up of Miocene limestone which covers northern and north-western coastal belt of the Island. It is used as a raw material for various industries but only cement and lime are being used for the construction industry. Except its chemical composition there is no available literature to study about other properties. Therefore the author carried out a series of laboratory tests to find out the mechanical properties of limestone in Sri Lanka. The objective of this paper is to make a note on the various properties of Miocene limestone and describe its suitability to use as an aggregate for the construction industry in Sri Lanka. Borehole samples (NX size) of limestone were obtained from various drilling sites in Northern Province of Sri Lanka and selected samples were prepared for different laboratory tests after visual observations. The tests were carried out according to ASTM Standards at the geotechnical and materials testing laboratories. The number of samples per each test was different. The range (and average result) for each property can be mentioned here as bulk density 2213-2643 (2452) kg/m3, water absorption 2.2-4.5 (1.91)%, porosity 1-15 (6.5)%, specific gravity 2.58-2.68(2.62), ultrasonic pulse velocity P wave 4480-6338 (5668) m/s and S wave 2688-3802 (3400) m/s, uniaxial compressive strength 11-92 (35)MPa, point load strength 1.2-7.1 (3.7)MPa, aggregate impact value, AIV 25-30 (28)%, LAAV 35-38 (36)%, and Brazilian tensile strength 2.1-4.4 (3.2)MPa. Poisson's ratio 0.12-0.68 (0.22) and modulus of elasticity 42-85 (62) GPa were obtained by using P and S ultrasonic wave velocity values. According to LAAV and AIV this limestone may be suitable as the base course material for road construction but may not be suitable for surface material of highways and rail road ballasts. Ultrasonic velocity waves indicate that limestone is highly compacted and solid. According to the compressive strength of solid limestone rock a few

  3. The Öland limestone - A Swedish stone used for more than one thousand years

    NASA Astrophysics Data System (ADS)

    Schouenborg, Björn; Wickström, Linda; Mikaelsson, Jan

    2016-04-01

    The second largest island in Sweden is the home of the "Öland limestone", a condensed and bedded limestone whose origin dates back to Lower Ordovician, i.e. about 480 M years ago. Öland is a part of the palaeocontinent Baltica that, at the time, was situated at low latitudes with deposition of the calcareous sediments in a cool water environment. The limestone on Öland represents a proximal ramp tectonic setting, with the oldest sediments deposited in the west and younger sediments deposited towards east and southeast. Fluctuating sea-levels have created erosional hard grounds such as the Flowery sheet. These hardgrounds are recognised by their vivid colours and trace fossils, and can be traced all over Baltica, but is maybe best represented on Öland. Ordovician limestones are present in many places in Sweden, but it is the occurrence on Öland that is the most renowned in a building stone perspective. One reason for this is the favourable trading location, an island off the Swedish East coast in middle of the trading routes between the Baltic countries and the continent. Other reasons are the pleasant aesthetical values with numerous orthoceratites and other fossils. The limestones on Öland differ in colour. From the red varieties (with oxidized iron) to brownish and grey. The bedding is mostly in the cm-scale which easily enables very exploitable thickness of slabs. Every mm limestone represents about 1000 years of deposition. The limestone has most likely been used in a very crude way for many thousand years, but archaeological evidence of a more industrialized usage is just a little more than 1000 years. It is known from the literature that the first official Swedish king, Gustav Vasa (16th century), desired this stone. At the time it was called "Öland marble", and the king "imported" specialists to process it further at the Royal Stone workshop on northern Öland. Remnants of tools and working sites still remain in an outdoor museum. Export of the

  4. The nature and distribution of flowing features in a weakly karstified porous limestone aquifer

    NASA Astrophysics Data System (ADS)

    Maurice, L. D.; Atkinson, T. C.; Barker, J. A.; Williams, A. T.; Gallagher, A. J.

    2012-05-01

    SummaryThe nature and distribution of flowing features in boreholes in an area of approximately 400 km2 in a weakly karstic porous limestone aquifer (the Chalk) was investigated using single borehole dilution tests (SBDTs) and borehole imaging. One-hundred and twenty flowing features identified from SBDTs in 24 boreholes have densities which decrease from ∼0.3 m-1 near the water table to ∼0.07 m-1 at depths of more than 40 m below the water table; the average density is 0.20 m-1. There is some evidence of regional lithological control and borehole imaging of three boreholes indicated that most flowing features are associated with marls, hardgrounds and flints that may be developed at a more local scale. Borehole imaging also demonstrated that many flowing features are solutionally enlarged fractures, suggesting that even in carbonate aquifers where surface karst is developed on only a small scale, groundwater flow is still strongly influenced by dissolution. Fully connected solutional pathways can occur over 100s, sometimes 1000s of metres. However, conduits, tubules and fissures may not always be individually persistent along a flowpath, instead being connected together and also connected to unmodified fractures to create a relatively dense network of voids with variable apertures (<0.1 cm to >15 cm). Groundwater therefore moves along flowpaths made up of voids with varying shape and character. Local solutional development of fractures at significant depths below the surface suggests that mixing corrosion and in situ sources of acidity may contribute to solutional enhancement of fractures. The study demonstrates that single borehole dilution testing is a useful method of obtaining a large dataset of flowing features at catchment-regional scales. The Chalk is a carbonate aquifer with small-scale surface karst development and this study raises the question of whether other carbonate aquifers with small-scale surface karst have similar characteristics, and what

  5. Quantifying and timing of long-term carbonate mobilisation in a limestone aquifer

    NASA Astrophysics Data System (ADS)

    Kirstein, J.; Gaupp, R.

    2012-04-01

    Carbonate dissolution during weathering, its intermediate storage by reprecipitation, and/or final export to the sea are major components in the global carbon cycle. The Thuringian Basin in the central part of Germany exposes deposits of the German Triassic Muschelkalk sequence consisting of limestone and dolostone beds. Partial dissolution, oxidation and iron redistribution is obvious in limestones along the slopes of the middle Saale river valley. These features are most prominent close to a Mid Quaternary valley floor (Elster terrace). They decrease down-section following fractures in homogeneous micritic limestones of the Lower Muschelkalk (Jena Formation), and reach a minimum close to the present groundwater table. It implies a discontinuous vertical migration of the groundwater table close to the valley slopes, spanning >700 ka of valley incision, and a coeval increase of oxidative weathering of sulfides and organic matter in the micritic carbonate. The recharging groundwater carries dissolved and particulate organic matter from the soil into fractures and pores. Microbial community oxidizes the organic material by using O2 that diffuses in from atmosphere. Due to the dissolved CO2 the water is undersaturated concerning carbonate minerals. The fissures enlarge by the water dissolving the limestones. The working hypothesis suggests the maximum of carbonate dissolution and descendant export within the vadose zone. Material export is supposed to occur dependant on climatic variations with microbial mediation in both dissolution and transient reprecipitation. Furthermore, the study area has the important advantage that the timing of the 100 m migration of the ground water table has a good age control due to topographic dating of terrace formation. Key aspects of this study are the quantification of long-term telodiagenetic transformations of the limestones, the timing of the involved processes and the analysis of current carbon fluxes both surface and subsurface

  6. Evolution and extinction of Permian fusulinid fauna in the Khao Tham Yai Limestone in NE Thailand

    NASA Astrophysics Data System (ADS)

    Hada, Shigeki; Khosithanont, Somboon; Goto, Hiroya; Fontaine, Henri; Salyapongse, Sirot

    2015-05-01

    The first detailed biostratigraphic investigation of a single limestone unit within the Khao Tham Yai Limestone shows it was deposited continuously in a shelf setting without any intercalation of clastic beds. It ranges from the Wordian (middle Middle Permian) up to the Wuchiapingian (lower Upper Permian). The limestone unit is divided in ascending order into three fusulinid zones, i.e. Colania, Lepidolina and Codonofusiella zones. The middle zone is characterized by an abundance of large-tested fusulinids characteristic of the Lepidolina Zone. Shell sizes of the fusulinid species in this zone display continuous rapid morphological change along a one-way evolutionary path from small, primitive species with simple structure to large, highly evolved species having a complicated wall structure. Fusulinid biostratigraphy in a single limestone unit elucidates evolution and extinction patterns of Permian fusulinids of the shallow-water Tethyan shelf area in the Indochina Block. Our study reveals that the boundary between the Guadalupian (Middle Permian) and Lopingian (Upper Permian) in the Khao Tham Yai Limestone is clearly defined as an abrupt change in the fusulinid assemblages from the elimination of large-tested Verbeekinids and Schwagerinids to the domination of small-shelled Schubertellids. The Schubertellids underwent slower evolutionary morphological change than earlier fusulinids and were decreasingly dominant through the Permian. A similar pattern of fusulinid evolution and extinction at the Guadalupian-Lopingian boundary occurs in shallow-water Tethyan shelf areas and mid-oceanic shallow-water environments in mid-Panthalassa. Eventually, even smaller fusulinids abruptly become extinct. Clastic deposits finally replace previous carbonate formations characterized by algae-foraminifera biota. It starts in the upper Middle Permian in the southern parts and spreads throughout the whole area in the lower Upper Permian in NE Thailand. These observations suggest

  7. Evaluation of Different Modeling Approaches to Simulate Contaminant Transport in a Fractured Limestone Aquifer

    NASA Astrophysics Data System (ADS)

    Mosthaf, K.; Rosenberg, L.; Balbarini, N.; Broholm, M. M.; Bjerg, P. L.; Binning, P. J.

    2014-12-01

    It is important to understand the fate and transport of contaminants in limestone aquifers because they are a major drinking water resource. This is challenging because they are highly heterogeneous; with micro-porous grains, flint inclusions, and being heavily fractured. Several modeling approaches have been developed to describe contaminant transport in fractured media, such as the discrete fracture (with various fracture geometries), equivalent porous media (with and without anisotropy), and dual porosity models. However, these modeling concepts are not well tested for limestone geologies. Given available field data and model purpose, this paper therefore aims to develop, examine and compare modeling approaches for transport of contaminants in fractured limestone aquifers. The model comparison was conducted for a contaminated site in Denmark, where a plume of a dissolved contaminant (PCE) has migrated through a fractured limestone aquifer. Multilevel monitoring wells have been installed at the site and available data includes information on spill history, extent of contamination, geology and hydrogeology. To describe the geology and fracture network, data from borehole logs was combined with an analysis of heterogeneities and fractures from a nearby excavation (analog site). Methods for translating the geological information and fracture mapping into each of the model concepts were examined. Each model was compared with available field data, considering both model fit and measures of model suitability. An analysis of model parameter identifiability and sensitivity is presented. Results show that there is considerable difference between modeling approaches, and that it is important to identify the right one for the actual scale and model purpose. A challenge in the use of field data is the determination of relevant hydraulic properties and interpretation of aqueous and solid phase contaminant concentration sampling data. Traditional water sampling has a bias

  8. The effect of limestone treatments on the rate of acid generation from pyritic mine gangue.

    PubMed

    Burt, R A; Caruccio, F T

    1986-09-01

    Surface water enters the Haile Gold Mine, Lancaster County, South Carolina by means of a small stream and is ponded behind a dam and in an abandoned pit. This water is affected by acidic drainage. In spite of the large exposures of potentially acid producing pyritic rock, the flux of acid to the water is relatively low. Nevertheless, the resulting pH values of the mine water are low (around 3.5) due to negligible buffering capacity. In view of the observed low release of acidity, the potential for acid drainage abatement by limestone ameliorants appears feasible.This study investigated the effects of limestone treatment on acid generation rates of the Haile mine pyritic rocks through a series of leaching experiments. Below a critical alkalinity threshold value, solutions of dissolved limestone were found consistently to accelerate the rate of pyrite oxidation by varying degrees. The oxidation rates were further accelerated by admixing solid limestone with the pyritic rock. However, after a period of about a month, the pyrite oxidation rate of the admixed samples declined to a level lower than that of untreated pyrite. Leachates produced by the pyrite and limestone mixtures contained little if any iron. Further, in the mixtures, an alteration of the pyrite surface was apparent.The observed behaviour of the treated pyrite appears to be related to the immersion of the pyrite grains within a high alkalinity/high pH environment. The high pH increases the rate of oxidation of ferrous iron which results in a higher concentration of ferric iron at the pyrite surface. This, in turn, increases the rate of pyrite oxidation. Above a threshold alkalinity value, the precipitation of hydrous iron oxides at the pyrite surface eventually outpaces acid generation and coats the pyrite surface, retarding the rate of pyrite oxidation. PMID:24214013

  9. Isotopic tracers of gold deposition in Paleozoic limestones, Southern Nevada

    SciTech Connect

    Peterman, Z.E.; Widmann, B.L.; Marshall, B.D.; Aleinikoff, J.N.; Futa, K.; Mahan, S.A.

    1994-12-31

    Strontium isotopic analyses of barren and mineralized Paleozoic carbonate rocks show that hydrothermal fluids added radiogenic strontium ({sup 87}Sr) to the mineralized zones. At Bare Mountain, samples collected from mineralized areas have {delta}{sup 87}Sr{sub t} values ranging from +3.0 to +23.0, whereas unmineralized carbonate rocks have {delta}{sup 87}Sr, values of {minus}0.6 to +2.9. In other ranges, {delta}{sup 87}Sr, values of the unmineralized carbonate rocks are even lower and virtually indistinguishable from primary marine values. This correlation of elevated {delta}{sup 87}Sr{sub t} values with mineralized zones provides a useful technique for assessing the mineral potential of the Paleozoic basement beneath Yucca Mountain, and may find broader use in mineral exploration in the Basin and Range province as a whole.

  10. Isotopic tracers of gold deposition in Paleozoic limestones, southern Nevada

    USGS Publications Warehouse

    Peterman, Z.E.; Widmann, B.L.; Marshall, B.D.; Aleinikoff, J.N.; Futa, K.; Mahan, S.A.

    1994-01-01

    Strontium isotopic analyses of barren and mineralized Paleozoic carbonate rocks show that hydrothermal fluids added radiogenic strontium (87Sr) to the mineralized zones. At Bare Mountain, samples collected from mineralized areas have ??87Srt values (per mil deviation from primary marine values) ranging from +3.0 to +23.0 (mean of this log-normal distribution is +7.0), whereas unmineralized carbonate rocks have ??87Srt values of -0.6 to +2.9 (mean of +1.07??1.03). In other ranges (Striped Hills, Spring Mountains, and ranges in the vicinity of Indian Springs Valley), ??87Srt values of the unmineralized carbonate rocks are even lower and virtually indistinguishable from primary marine values. This correlation of elevated ??87Srt values with mineralized zones provided a useful technique for assessing the mineral potential of the Paleozoic basement beneath Yucca Mountain, and may find broader use in mineral exploration in the Basin and Range province as a whole.

  11. Playing My Heart Out: Original Play as Adventure.

    ERIC Educational Resources Information Center

    Donaldson, O. Fred

    1999-01-01

    "Original" play denotes play that is pre-cultural--before conceptualizations and learned responses. Four anecdotes about play with an infant with Down's syndrome, a child with leukemia, a lioness, and a dying woman illustrate the connections between beings and between the ordinary and the sacred during trusting, fearless, playful encounters. (SV)

  12. Imagination, Playfulness, and Creativity in Children's Play with Different Toys

    ERIC Educational Resources Information Center

    Mo????ller, Signe?? Juhl?

    2015-01-01

    Based on a four-month experimental study of preschool children's play with creative-construction and social-fantasy toys, the author examines the in?uence of both types of toys on the play of preschool children. Her comparative analysis considers the impact of transformative play on the development of imagination during play activities and…

  13. Child's Play: Revisiting Play in Early Childhood Settings.

    ERIC Educational Resources Information Center

    Dau, Elizabeth, Ed.; Jones, Elizabeth, Ed.

    Noting that play is an essential aspect of learning for young children, this book presents a collection of articles on children's play in Australia. Part 1, "Play, Development, and Learning," contains the following chapters: (1) "The Role of Play in Development and Learning" (Ann Glover); (2) "Stop, Look, and Listen: Adopting an Investigative…

  14. Tectonic origin for polygonal normal faults in pelagic limestones of the Cingoli anticline hinge (Italy)

    NASA Astrophysics Data System (ADS)

    Petracchini, Lorenzo; Antonellini, Marco; Billi, Andrea; Scrocca, Davide

    2016-04-01

    Polygonal faults are a relatively-recent new class of normal faults which are thought to be formed during early burial and diagenesis as a consequence of heterogeneous lateral volume changes. Polygonal faults are non-systematically oriented and, in map view, they form rhombus-, pentagon-, or hexagon-like pattern, suggesting a non-tectonic origin. Furthermore, polygonal faults are layer bound and they are restricted to particular stratigraphic level. Predicting the pattern of polygonal normal fault results crucial for geofluid exploration and exploitation, but, despite the large number of studies, the origin of these faults remains still largely controversial. One of the main reason for this uncertainty is that they are poorly known in outcrops. Polygonal faults have been identified in few localities within Mesozoic chalk (United Kingdom, France, and Egypt), in Paleogene claystone (Belgium), and in the Cretaceous Khoman Formation (Egypt) where polygonal faults have been observed in an extensive exposure of chalk. In this study, we describe an outcrop in the Cingoli anticline hinge, which is located at external front of the northern Apennines fold-thrust belt (Italy), showing normal faults that we interpreted as syn-tectonically (syn-thrusting) polygonal faults. The outcrop shows three vertical exposures of sub-horizontal fine-grained marly limestones with chert interlayers of Albian-Turonian age. Intraformational short normal faults affect the carbonate and chert beds. These faults are poorly-systematic and they cut through the carbonate beds whereas usually stop against the chert layers. The fault surfaces are often characterized by slickolites, clayey residue, and micro-breccias including clasts of chert and carbonate. Fault displacement is partly or largely accommodated by pressure solution. At the fault tips, the displacement is generally transferred, via a lateral step, to an adjacent similar fault segment. The aim of our study is to understand the nucleation

  15. Multimodal Play and Adolescents: Notes on Noticing Laughter

    ERIC Educational Resources Information Center

    Vasudevan, Lalitha

    2015-01-01

    In this article, I explore laughter as a form of multimodal play in which adolescents' engage across contexts and in various configurations. With a few recent exceptions, a focus on unscripted play is largely missing from ongoing research and discussion about the education of adolescents. Whereas the space to play has been vitally important to the…

  16. Play Behaviors of Parents and Their Young Children with Disabilities

    ERIC Educational Resources Information Center

    Childress, Dana C.

    2011-01-01

    Learning to explore, communicate, and interact with others and the environment through play can be problematic for young children with disabilities, but with parental support, children can learn and interact successfully during play activities. To determine how parents engage their preschool children with disabilities in play and what behaviors…

  17. Sensorhesis as a Motive for Play and Stereotyped Behavior.

    ERIC Educational Resources Information Center

    Ellis, M. J.

    This paper attempts a unified explanation of such apparently non-utilitarian behaviors as curiosity, manipulation, and exploration as manifestations of "playful behaviors" on the one hand and stereotyped responses on the other. Sensorhesis names the new theory offered to explain the existence and nature of playful behavior. Play and stereotyped…

  18. Museum Superheroes: The Role of Play in Young Children's Lives

    ERIC Educational Resources Information Center

    Krakowski, Pamela

    2012-01-01

    This article explores the role of play in an art museum. Reflecting upon a kindergarten field trip to the Warhol Museum in which children's play was the centerpiece of the museum experience, the author examines what early childhood theorists have written about the value of play in young children's lives. She shows how the Warhol's program for…

  19. Foreign Ludicity in Online Role-Playing Games

    ERIC Educational Resources Information Center

    Liang, Mei-Ya

    2012-01-01

    This article reports on an explorative case study which, in the first place, aimed to ascertain different types of foreign language play in online role-playing in "Second Life," and which, secondly aimed to describe how various sources of contextual support can explain this foreign language play. Students' written conversation was analyzed and…

  20. Emancipating Play: Dis/Abled Children, Development and Deconstruction

    ERIC Educational Resources Information Center

    Goodley, Dan; Runswick-Cole, Katherine

    2010-01-01

    This paper reflects critically on the meaning of play, especially as it relates to disabled children and their experiences. We explore the close alliance of play to cognitive and social development, particularly in the case of psychologies of development, and reveal a dominant discourse of the disabled child as a non-playing object that requires…

  1. Exploring Mars

    NASA Astrophysics Data System (ADS)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  2. Fault zones in Triassic Muschelkalk limestones of the Upper Rhine Graben: Infrastructure characterization and permeability structure analyses

    NASA Astrophysics Data System (ADS)

    Meier, Silke; Bauer, Johanna F.; Philipp, Sonja L.

    2014-05-01

    zones in the past. This shows that open fractures with orientations parallel to fault zones may be pathways for fault zone parallel fluid flow in geothermal reservoirs. By contrast, the well-developed fault cores, comprising fault gouge, fault breccia and host rock lenses, may be potential barriers for fluid flow in inactive fault zones. It is concluded that the fault damage zones in Muschelkalk limestones are potential drilling targets of geothermal wellbores in the URG. Hydraulic stimulation may be required, however, to improve the connectivity of the natural fracture network. The presented studies help to predict the permeability of fault-related geothermal reservoir rocks and minimize the exploration risk of geothermal projects. This project is part of the Research and Development Project AuGE (Outcrop Analogue Studies in Geothermal Exploration). Project partners are the companies Geothermal Engineering GmbH and GeoEnergy GmbH as well as the Universities of Heidelberg and Erlangen. The project is funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) within the framework of the 5th Energy Research Program (FKZ 0325302).

  3. A Case Study of Gendered Play in Preschools: How Early Childhood Educators' Perceptions of Gender Influence Children's Play

    ERIC Educational Resources Information Center

    Chapman, Rachel

    2016-01-01

    This research aimed to explore children's play in relation to gender stereotypes and beliefs and practices of educators in preschool settings. A feminist poststructuralist approach framed the design of the research and data were collected in two settings through predetermined categories of play during periods of spontaneous free play. The question…

  4. The Aesthetics of Play: A Didactic Study of Play and Culture in Preschools. Uppsala Studies in Education 62.

    ERIC Educational Resources Information Center

    Lindqvist, Gunilla

    Based on Vygotsky's theory amongst others that play reflects different aspects of children's development and culture, this thesis explores in depth how aesthetic activities can influence children's play and the nature of the connections between play and culture, primarily in the aesthetic forms of drama and literature. The thesis also presents…

  5. North Dakota`s Dickinson Lodgepole discovery: A Preliminary exploration model

    SciTech Connect

    LeFever, J.A.; Halabura, S.P.; Martiniuk, C.D.; Fischer, D.W.

    1995-08-14

    Interest in the Mississippian Lodgepole formation of North Dakota has intensified since the successful completion of the Duncan Oil Inc. 1-11 Knopik flowing 2,707 b/d of oil and 1.55 MMcfd of gas 430 cu m of oil and 43,891 cu m of gas. The play began when Conoco drilled an in-field wildcat in an attempt to establish deeper production in Dickinson oil field. The discovery well, 74 Dickinson State, was completed in a clean lower Lodgepole limestone section that is thought to represent a Waulsortian mound. The most important questions asked concerning the Lodgepole play are whether or not it will step out of the Dickinson area, what are the factors that control the development of these mounds, what controlled the development of the reservoir and trap, and how it was charged with oil. Other than the reservoir section, the most significant feature observed from wireline logs of the area is the anomalously thick Bakken formation (Mississippian-Devonian). This observation is important to understanding the Lodgepole play and can be used to help explore for similar features elsewhere in the basin. The paper describes the regional setting, the Lodgepole stratigraphy, deposition, regional equivalents, and a salt collapse model that can readily explain the features observed at the Dickinson field.

  6. Recovery and recycling of limestone in LEC flue gas desulfurization. Final report, September 1, 1991--August 31, 1992

    SciTech Connect

    Gardner, N.C.; Boo, J.Y.; Culver, L.

    1992-09-01

    Prudich et. al. have proposed an attractive technology called Limestone Emission Control (LEC) for removing sulfur dioxide from flue gases. Beds of 1/8 inch wet limestone particles absorb the sulfur dioxide from the gases on contact. Sulfite and sulfate salts deposit on the surface of the particles; however, the gas never reaches the interior, limiting the limestone utilization to approximately 20% or less. The unreacted portion of the limestone can be recovered by mechanical grinding and recycling, enabling high overall sorbent utilization. Favorable economics are derived from small equipment, simplicity, and low sorbent costs. This project is a wet method for grinding and recovering the spent limestone from the LEC process, utilizing an impeller fluidizer, a new type of slurry processor. It consists of a cylindrical vessel with an impeller at one end. The impeller, driven at high rpm, concentrates the gravel size limestone in a rotating torus at the top of the cylinder, where the coating is abraded off by particle-particle impaction. The impeller generates sufficient pressure head to serve as a slurry pump. It combines the operation of wet grinding, washing, and transporting the spent and recovered limestone as an aqueous slurry. The fluidizer may be advantageous over dry grinding in the aspects of sharpness of separation, transport convenience, equipment erosion, and sorption bed cementation.

  7. Play and Positive Group Dynamics

    ERIC Educational Resources Information Center

    Thompson, Pam; White, Samantha

    2010-01-01

    Play is an important part of a child's life and essential to learning and development (Vygotsky, 1978). It is vital that students participate in play and that play be conducted in a restorative manner. Play allows a variety of group dynamics to emerge. Irvin Yalom (1995) identifies 11 curative factors of the group experience. These factors include…

  8. Play Therapy in Elementary Schools

    ERIC Educational Resources Information Center

    Landreth, Garry L.; Ray, Dee C.; Bratton, Sue C.

    2009-01-01

    Because the child's world is a world of action and activity, play therapy provides the psychologist in elementary-school settings with an opportunity to enter the child's world. In the play therapy relationship, toys are like the child's words and play is the child's language. Therefore, children play out their problems, experiences, concerns, and…

  9. Playful Learning and Montessori Education

    ERIC Educational Resources Information Center

    Lillard, Angeline S.

    2013-01-01

    Although Montessori education is often considered a form of playful learning, Maria Montessori herself spoke negatively about a major component of playful learning--pretend play, or fantasy--for young children. In this essay, the author discusses this apparent contradiction: how and why Montessori education includes elements of playful learning…

  10. Passive treatment of acid mine drainage in systems containing compost and limestone: Laboratory and field results

    SciTech Connect

    Watzlaf, G.R.; Pappas, D.M.

    1996-12-31

    Passive, down-flow systems, consisting of compost and limestone layers, termed successive alkalinity producing systems (SAPS), may be well suited for treatment of mine drainage containing ferric iron and/or aluminum. A column, simulating a SAPS, has been operated in the laboratory for 52 weeks. The 0.16-m diameter column consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost thick layer of limestone, a 0.76-m thick layer of spent mushroom compost and 0.91 m of free standing water. Actual AMD (pH = 3.02, acidity = 218 mg/L (as CaCO{sub 3}), SO{sub 4} = 600 mg/L, Fe = 16.0 mg/L, Mn = 12.1 mg/L, and Al = 17.1 mg/L) was applied to the column at a rate of 3.8 mL/min. Effluent pH has remained above 6.2 (6.2-7.9) in the column system. A SAPS located in Jefferson County, PA has been monitored for the past 4.5 years. The SAPS has an approximate area of 1000 m{sup 2} and contains a 0.4-m thick layer of limestone, a 0.2-m thick layer of spent mushroom compost, and 1.5 m of free standing water. Mine water (acidity = 335 mg/L (as CaCO{sub 3}), SO{sub 4} = 1270 mg/L, Fe = 246 mg/L, Mn = 38.4 mg/L, and Al = <0.2 mg/L) flowed into the SAPS at a rate of 140 L/min. Water samples from the field and laboratory systems have been collected at strategic locations on a regular basis and analyzed for pH, alkalinity, acidity, Fe{sup 2+}, total Fe, Mn, Al, SO{sub 4}, Ca, Mg, Na, Co, Ni, and Zn. Alkalinity has been generated in both field and laboratory systems by a combination of limestone dissolution and sulfate reduction. The column generated an average of 378 mg/L of alkalinity; 74% due to limestone dissolution and 26% due to bacterial reduction of sulfate. The field SAPS generated an average of 231 mg/L of alkalinity and exhibited seasonal trends.

  11. Cretaceous planktic foraminiferal biostratigraphy of the Calera Limestone, Northern California, USA

    USGS Publications Warehouse

    Sliter, W.V.

    1999-01-01

    The Calera Limestone is the largest, most stratigraphically extensive limestone unit of oceanic character included in the Franciscan Complex of northern California. The aim of this paper is to place the Calera Limestone at its type locality (Rockaway Beach, Pacifica) in a high-resolution biostratigraphy utilizing planktic foraminifers studied in thin section. A section, about 110 m-thick, was measured from the middle thrust slice exposed by quarrying on the southwest side of Calera Hill at Pacifica Quarry. Lithologically, the section is divided in two units; a lower unit with 73 m of black to dark-grey limestone, black chert and tuff, and an upper unit with 36.8 m of light-grey limestone and medium-grey chert. Two prominent black-shale layers rich in organic carbon occur 11 m below the top of the lower black unit and at the boundary with overlying light-grey unit, yielding a total organic content (TOC) of 4.7% and 1.8% t.w., respectively. The fossiliferous Calera Limestone section measured at Pacifica Quarry, from the lower black shale, contains eleven zones and three subzones that span approximately 26 m.y. from the early Aptian to the late Cenomanian. The zones indentified range from the Globigerinelloides blowi Zone to the Dicarinella algeriana Subzone of the Rotalipora cushmani Zone. Within this biostratigraphic interval, the Ticinella bejaouaensis and Hedbergella planispira Zones at the Aptian/Albian boundary are missing as are the Rotalipora subticinensis Subzone of the Biticinella breggiensis Zone and the overlying Rotalipora ticinensis Zone in the late Albian owing both to low-angle thrust faulting and to unconformities. The abundance and preservation of planktic foraminifers are poor in the lower part and improve only within the upper G. algerianus Zone. The faunal relationship indicate that the lower black shale occurs in the upper part of the G. blowi Zone and correlates with the Selli Event recognized at global scale in the early Aptian. The upper black

  12. Rough and Tumble Play 101

    ERIC Educational Resources Information Center

    Carlson, Frances

    2009-01-01

    Many people fear that play-fighting or rough and tumble play is the same as real fighting. There is also a fear that this rough play will become real fighting if allowed to continue. Most of all, parents and teachers fear that during the course of rough and tumble play a child may be hurt. To provide for and allow children to play rough without…

  13. Limestone percussion tools from the late Early Pleistocene sites of Barranco León and Fuente Nueva 3 (Orce, Spain).

    PubMed

    Barsky, Deborah; Vergès, Josep-María; Sala, Robert; Menéndez, Leticia; Toro-Moyano, Isidro

    2015-11-19

    In recent years, there is growing interest in the study of percussion scars and breakage patterns on hammerstones, cores and tools from Oldowan African and Eurasian lithic assemblages. Oldowan stone toolkits generally contain abundant small-sized flakes and their corresponding cores, and are characterized by their structural dichotomy of heavy- and light-duty tools. This paper explores the significance of the lesser known heavy-duty tool component, providing data from the late Lower Pleistocene sites of Barranco León and Fuente Nueva 3 (Orce, Spain), dated 1.4-1.2 Myr. Using quantitative and qualitative data from the large-sized limestone industries from these two major sites, we present a new methodology highlighting their morpho-technological features. In the light of the results, we discuss the shortfalls of extant classificatory methods for interpreting the role of percussive technology in early toolkits. This work is rooted in an experimental program designed to reproduce the wide range of percussion marks observed on the limestone artefacts from these two sites. A visual and descriptive reference is provided as an interpretative aid for future comparative research. Further experiments using a variety of materials and gestures are still needed before the elusive traces yield the secrets of the kinds of percussive activities carried out by hominins at these, and other, Oldowan sites. PMID:26483530

  14. Limestone percussion tools from the late Early Pleistocene sites of Barranco León and Fuente Nueva 3 (Orce, Spain).

    PubMed

    Barsky, Deborah; Vergès, Josep-María; Sala, Robert; Menéndez, Leticia; Toro-Moyano, Isidro

    2015-11-19

    In recent years, there is growing interest in the study of percussion scars and breakage patterns on hammerstones, cores and tools from Oldowan African and Eurasian lithic assemblages. Oldowan stone toolkits generally contain abundant small-sized flakes and their corresponding cores, and are characterized by their structural dichotomy of heavy- and light-duty tools. This paper explores the significance of the lesser known heavy-duty tool component, providing data from the late Lower Pleistocene sites of Barranco León and Fuente Nueva 3 (Orce, Spain), dated 1.4-1.2 Myr. Using quantitative and qualitative data from the large-sized limestone industries from these two major sites, we present a new methodology highlighting their morpho-technological features. In the light of the results, we discuss the shortfalls of extant classificatory methods for interpreting the role of percussive technology in early toolkits. This work is rooted in an experimental program designed to reproduce the wide range of percussion marks observed on the limestone artefacts from these two sites. A visual and descriptive reference is provided as an interpretative aid for future comparative research. Further experiments using a variety of materials and gestures are still needed before the elusive traces yield the secrets of the kinds of percussive activities carried out by hominins at these, and other, Oldowan sites.

  15. Pakistan has unventured regions, untested plays

    SciTech Connect

    Quadri, V.N.; Quadri, S.M.J.G.

    1998-01-05

    Quantitative numerical models for integrating known geological, geophysical, and geochemical processes, including 3D basin simulation and visualization, are important innovations that are helping to reduce the cost of exploration. It is unfortunate that against this background, in Pakistan there still exist some unventured sedimentary basins and untested plays. This article discusses in some detail one of the unventured regions, the Peshawar basin, and an untested play area, the Punjab platform zone. The intermontane Peshawar basin lies immediately north of Potwar-Kohat basin, the latter the site of several oilfields. Source rocks for gas, condensate, and possibly oil exist in the Sulaiman Range located in the Punjab zone.

  16. Play, Play Therapy, Play Research. Proceedings of the International Symposium (Amsterdam, the Netherlands, September 1985).

    ERIC Educational Resources Information Center

    Kooij, Rimmert van der; Hellendoorn, Joop

    After an introduction which briefly discusses emotional, therapeutic, phenomenological, cognitive, and developmental perspectives on play, this volume presents the complete texts of all the main lectures and a few short papers that were given at the International Symposium on Play, Play Therapy, and Play Research. Papers in part 1 concern certain…

  17. A Homoploid Hybrid Between Wild Vigna Species Found in a Limestone Karst.

    PubMed

    Takahashi, Yu; Iseki, Kohtaro; Kitazawa, Kumiko; Muto, Chiaki; Somta, Prakit; Irie, Kenji; Naito, Ken; Tomooka, Norihiko

    2015-01-01

    Genus Vigna comprise several domesticated species including cowpea and mungbean, and diverse wild species. We found an introgressive hybrid population derived from two wild species, Vigna umbellata and Vigna exilis, in Ratchaburi district, Thailand. The hybrid was morphologically similar to V. umbellata but habituated in a limestone rock mountain, which is usually dominated by V. exilis. Analyzing simple sequence repeat loci indicated the hybrid has undergone at least one round of backcross by V. umbellata. We found the hybrid acquired vigorous growth from V. umbellata and drought tolerance plus early flowering from V. exilis, and thus has taken over some habitats of V. exilis in limestone karsts. Given the wide crossability of V. umbellata, the hybrid can be a valuable genetic resource to improve drought tolerance of some domesticated species. PMID:26648953

  18. On the role of organic adlayers in the anomalous water sorptivity of Lépine limestone.

    PubMed

    Ioannou, Ioannis; Hoff, William D; Hall, Christopher

    2004-11-01

    Sorptivity data are reported for the capillary absorption of water, ethanol, propan-2-ol, and n-heptane by the calcitic limestone Lépine (Lavoux à grain). The data confirm that the water sorptivity is anomalously low, an indication of partial wetting by water. Results are expressed in terms of a wetting index. The water sorptivity increases after heat treatment and chemical oxidation by hydrogen peroxide bleaching, while the sorptivity with organic liquids is unchanged. These treatments, therefore, increase the water wetting index. The results provide strong evidence that the presence of a natural organic adlayer is responsible for the anomalously low water sorptivity of this particular limestone. This natural water repellency effect may be exploited in developing chemical treatments to modify the water transport properties of stone. PMID:15380433

  19. Attenuation of stormwater contaminants from highway runoff within unsaturated limestone, Dade County, Florida

    USGS Publications Warehouse

    Waller, Bradley G.; Klein, Howard; Lefkoff, Lawrence J.

    1984-01-01

    Infiltration of stormwater in heavily urbanized parts of Dade County, Florida, is a prime source of recharge to the unconfined Biscayne aquifer, the sole source of drinking water for southeast Florida. Ponded stormwater at the test site contained greater concentrations of lead, zinc, manganese, nitrogen (except nitrate), and phosphorus than the water which percolated through the unsaturated limestone. Attenuation of some stormwater contaminants in the surface soils and limestone is indicated at the test site adjacent to a busy throughfare. Lead concentrations of 610 micrograms per kilogram and zinc concentrations of 91 micrograms per kilogram were found in the thin surface soils, nearly 20 times more than the concentrations of these metals at greater depth. In contrast, soil and rock sample at a control site remote from heavy traffic contained low concentrations of metals and showed little variation in concentration with depth. (USGS)

  20. Microstructural study of sulfate attack on ordinary and limestone Portland cements at ambient temperature

    SciTech Connect

    Irassar, E.F.; Bonavetti, V.L.; Gonzalez, M

    2003-01-01

    This paper presents an investigation on the mechanism of sulfate attack on Portland cements (PCs) containing limestone filler. It is based on the analysis of microstructure and composition of mortar specimens (ASTM C 1012) stored for 2 years in sodium sulfate solution (0.352 M). Microstructure was studied using quantitative X-ray diffraction (XRD) on samples taken from the surface to the core of the specimens. The profile of compounds formed by sulfate attack was determined millimeter by millimeter at 1 and 2 years. Results show that sulfate attack in mortars containing limestone filler is characterized by an inward movement of the reaction front leading first to the formation of ettringite, later to gypsum deposition, and finally to thaumasite formation when the decalcification of mortar leads to the breakdown of C-S-H.