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Serbian Tertiary ultrapotassic province is part of widespread but not voluminous basaltic magmatism in Serbia. Two principal groups of ultrapotassic rocks are recognized; the lamproite affinity group (LAG) and the kamafugite affinity group (KAG). My results demonstrate three dominant low-pressure evolutional processes: magma mixing and fractional crystallization, analcimization and heteromorphism. The two suites of ultrapotassic rocks show large ranges of Sr and Nd isotopic values but a restricted variation of Pb isotopes. LAG is characterized by wide ranges of Sr and Nd isotopes (87Sr/86Sri 0.70735- 0.71299, 143Nd/144Ndi 0.51251-0.51216). KAG is isotopically homogeneous with a limited range of Sr-Nd isotopes (87Sr/86Sri 0.70599-0.70674, 143Nd/144Ndi 0.51263-0.51256). The Pb isotope compositions of both groups are similar (206Pb/204Pb 18.581-18.832, 207Pb/204Pb 15.624-15.696 and 208Pb/204Pb 38.744-38.987), and fall within the pelagic sediment field resembling Mesozoic flysch sediments from the Vardar ophiolitic composite suture zone. Highly variable Sr and Nd isotopic signatures of primitive-LAG rocks correlate with REE fractionation and enrichment of the HFSE. I explain this correlation using vein+wall-rock melting model, invoking the presence of different metasomatic domains (veins with phlogopite, Cpx and F-apatite) that are out of isotopic equilibrium with the peridotite wall rock. Relatively uniform Sr and Nd isotopic data of KAG rocks, similar trace element patterns and small but regular variations of HFSE ratios, indicate different degrees of melting of a relatively homogeneously metasomatized mantle source. Geochemical modelling implies the role of phlogopite, apatite and Ti-oxide in their mantle source.
The present work is a paleolimnological orientated approach to refine and improve the indicator ability of freshwater ostracods from Holocene and Late glacial deposits in northeast Germany. The thesis follows two different approaches, one utilizes quantitative paleoenvironmental analysis, while the other evaluates ecological investigations of living specimens to extend the potential indicator group. For the first time quantitative ostracod analysis are carried out for a lacustrine basin (lake Krakower See) and a near-shore locality (Pudagla lowland) in the study area. The ecological investigation of living ostracods comprises 96 localities. The evaluation focused on environmental variables, which explain significantly the species composition. A canonical correspondence analysis identified at least four environmental parameters - water temperature, conductivity, pH-value, and mean water depth – which have an effect on ostracod assemblages. An extended analysis, which included only a subset of lake sites, revealed also that the former three environmental parameters affect the ostracod lake fauna, whereas the water temperature is the dominant factor. A temperature-transfer function could be regressed and calculated from the given trainingset by a weighted average model. These estimates can now be use in future paleolimnological investigations in northeast Germany to quantify the paleotemperature.
Recent geochemical and mineralogical alteration processes in tropical coastal sediments of Vietnam
(2006)
The dissertation contains two main parts: (i) Syn-sedimentary hydrodynamic processes & relationship with elemental distribution, clay matter, (ii) Short-term mineral alteration during early diagenes. Samples were taken from the uppermost one metre (<50 year old in RRD, < 300 y old in south central VN). In part one, three principal hydrodynamic factors can be revealed based on End-Member Modelling Algorithm (EMMA), for the polymodal grain-size distribution patterns in coastline of VN (i) Accumulation factor: accumulation of terrigenous sediments linked with a grain size separation (distance dependence), (ii) Erosion factor: synsedimentary erosion by wave activities, (iii) Aeolian factor: deposition from neighbour sand bar by wind (typically only for low sedimentation rate, like in South Central Coast but not to detect in RRD). Distributions of clay matter and chemical elements in the coastal sediments in Vietnam are strongly influenced by hydrodynamic forces (distance from the coastline). In part two, particle-wise analysis by TEM allowed to determined four main mixed layer series: di-Vermiculite/Smectite-ml, Kaolinite/ Expandable-ml, Illite/Smectite-ml, Chlorite/Saponite-ml. Three principal mineral alteration processes can be detected in coastal sediments during early diagenesis: Dissolution, Smectitization, Kaolinitization, based on XRD (CSD, peak area) & TEM-EDX (particle morphology, chemical formula, polytype, particle frequency). Dissolution process of clay matter is typically in the coastal alkaline condition. It is a function of diagenetic time. Dissolution begins with a higher degree of dislocation and is followed by step-wise delamination & dissolution of the first stacks Smectitization (mirrored in diVS-ml series) alters mica-like structures (illite, dioctahedral vermiculite) to smectitic structures (Beidellite, Montmorillonite). Smectitization process occurs in group-wise layer by layer transforming mechanism (mica-like layer to smectitic layer). Each step is indicated by a gauss-like distribution of the octahedral layer charge with K as trigger. Kaolinitization of KE series alters smectitic structure (beidellite, smectitic KE-ml) to kaolinitic structure (kaolinitic KE-ml, kaolinite) "interlayer by interlayer" transformation of KE-ml series is comparable to kaolinitization mechanism discussed by Dudek et al. (2006).OH- groups in ambient could be the trigger. Mangroves biota influences the sediments in two main pathways: Nutrients supply & trapping function (clay matter, heavy metals)Interaction of active root-layer: intensification of dissolution, smectitization & kaolinitization: uptake of K, Na by mangrove root is possible trigger Human activities like shrimp cultivation have stopped the influences of the former active roots.Besides, erosion process related to water discharge gives rise to dispersion of clay species & heavy metals => more toxic for ecosystem.
The non-natural substances in commonly used UV protection creams such as TiO2, are known to have a photocatalytic side effect, which is very harmful to human skin. This study presents some properties of clays and clays minerals concerning UV protection potential, which can be very helpful for the development of new UV protection cream generation. Clays and clay minerals are demonstrated that they have potential to absorb UV-radiation. The structures of clay particles in cream were shown to be dependent on the layer charge of clay minerals. The total amount of Fe2C>3 in chemical composition of clay plays a key role in determining the UV-absorption ability of the clay matter. Moreover, the UV-absorption ability also depends on the expandable or non- expandable property of the clay. The studies were also performed on the mixtures of wool-wax-alcohol cream and nanosuspension obtained by the extraction of fungi mass Ganoderma pfeifferi by using plantacare together with clay. The combination of clays and nanosuspension increased its UV-absorption ability. The skin model test was performed in vivo in mouse ears with skin flora Escherichia coli and infectious bacteria Staphylococcus aureus in order to determine the effects of cream samples on skin under UV irradiation and skin infection. From the results of characterization of clays and clay minerals properties in UV protection cream, this study also brings some ideas about products designing.
Die vorliegende Arbeit behandelt die Gewässernetzentwicklung im Bereich der Pommerschen Haupteisrandlage (W2), des eng benachbarten Frühpommerschen Vorstoßes (W2max) und der südlich angrenzenden Sanderflächen in einem Ausschnitt, der ungefähr zwischen Krakow, Goldberg und Malchow im mittleren Mecklenburg gelegen ist. Ziel der Untersuchungen ist die Verknüpfung geomorphologischer, bodenkundlicher, paläobotanischer, paläolimnologischer, archäologischer und historischer Befunde zur paläohydrographischen Rekonstruktion der Gewässer seit dem Spätpleistozän, eines etwa 14.000 Jahre umfassenden Zeitraums. Die hierbei präferierte multidisziplinäre Bearbeitungsweise limnischer Sedimentsequenzen aus Seebohrungen in Verbindung mit landseitigen bodenkundlich–geomorphologischen Kartierungen stellt (noch immer) ein Novum in der Gewässerforschung Mecklenburg-Vorpommerns dar und liefert wichtige Ergänzungen zu Modellvorstellungen der Gewässerentwicklung. Thematische Schwerpunkte werden für die verknüpfte, spätpleistozäne Becken– und Durchbruchstalentwicklung, die fortan archivierte limnisch–telmatische Sedimentationsgeschichte, die Wasserstandsentwicklung und die Wechselwirkung Mensch und Gewässer gesetzt. Zugleich erlauben die bodenkundlichen Arbeiten im Gewässerumfeld Aussagen zur Bodengenese und Landnutzungsgeschichte besonders innerhalb der Nossentiner–Schwinzer Heide. Im Zuge der palynologischen Bearbeitung der Seesedimente durch Dritte liegt desweiteren eine lückenlose Vegetationsgeschichte des Untersuchungsgebietes seit dem Allerød vor, die ebenso wertvolle Ableitungen zur regionalen Siedlungs- und Landnutzungsgeschichte erlaubt. Diatomeen–basierte paläolimnologische Aussagen ebenfalls Dritter fokussieren auf die postglaziale Trophie– und die Wasserstandsentwicklung der untersuchten Seen.
Mind the gap: Information gaps and bridging options in assessing in-situ conservation achievements
(2008)
The biodiversity crisis has gained political attention on a global level. The “2010 Target” of the Convention on Biological Diversity (CBD) aims to significantly reduce the loss of biodiversity by 2010. In order to achieve this, a network of representative and effectively managed protected areas is to be established. The effectiveness of protected areas thus represents one indicator for progress towards the CBD’s 2010 Target. However, indicators require information. The present study, in a first step, reviews the availability of open access long-term ecological data for assessing protected area effectiveness. This review shows two parallel – though contradictory – phenomena: data overkill and data scarcity. While the number of online databases providing open access data on biodiversity has grown tremendously, no long-term ecological data for a larger set of protected areas can be openly accessed. Reasons for this data scarcity are discussed. Based on this lack of information, in a second step, a method to bridge information gaps through social science research is aspired. An innovative Conservation Success Framework is developed, which defines and relates conservation needs, conservation capacity and conservation actions, its three main components. The basic assumption is that conservation can only be successful where the conservation capacity exists that is required to implement the conservation actions determined by the conservation needs. The framework was used to develop open and closed questionnaires for application in two Mexican biosphere reserves, the Sierra Gorda and the Sierra de Manantlán. As "conservation success" is often immeasurable in protected areas in practice due to unspecific conservation objectives the term is for the case studies substituted by “conservation achievements”, i.e. clearly noticeable effects from conservation actions. Overall, almost 60 interviews were conducted with different stakeholder groups. The gained information is validated through social science research techniques, such as triangulation of perspectives and active and passive observation. Based on this, conservation needs are identified and conservation capacities summarised and discussed for both case study sites. Implemented conservation actions addressing identified conservation needs and conservation capacity constraints are then analysed. In addition, noticeable effects from conservation actions on the state of biodiversity at case study sites, i.e. the conservation achievements, are described. Where locally available, non-open access data (as opposing open access data) are used to verify the findings from the social science research. Identified conservation achievements at both case study sites are evident both from quantitative information (for example forest cover increase according to non-open access data) and qualitative information (for example perceived change in the occurrence of illegal activities according to interviews). In addition, rather “intangible” indicators that can only be revealed through qualitative surveys are identified for both sites. This study thus highlights the crucial importance of integrating different types of data, ecological and socio-economic, as well as quantitative and qualitative ones. The present study concludes with a series of recommendations 1) to local practitioners at the two case study sites, and 2) to the international conservation community. Local practitioners may benefit from the present study because its results provide for each site a) an overview of existing conservation needs and implemented conservation actions; b) an easy way to identify action gaps; c) a baseline to identify progress indicators; and d) an overview of diverse perspectives on the current effectiveness of the biosphere reserves. These benefits are considered of particular importance as they can be influential in the revision of the site’s management plans, which both are now approximately ten years old and will soon be revised. The international conservation community will not be able to make a clear statement in the year 2010 about the effectiveness of protected areas on a global level due to a lack of information and transparency. However, the year 2010 should not be considered an end point for measuring progress in in-situ conservation; instead protected area quality standards must be created, effectiveness evaluations institutionalised and efforts to foster regular reporting must continue. Consequently, a scheme of consolidated actions from local to national and international level is proposed that could help to sustainably bridge existing information gaps and close them on the long run. In the end, progress reporting on the effectiveness of protected areas, and other indicators, can only improve if different governance levels “mind the information gaps” in cooperation, until continued information gathering and sharing hopefully closes these gaps one day.
The New Zealand coal covering the complete maturity range from peat to high volatile bituminous, thus from early diagenetic to catagenesis coalification levels, has been studied in order to bring out new insights into molecular alterations, macromolecular structural evolution, elemental-compositional changes as function of maturation and to propose which processes cause these changes. As particular note from the previous observations that many immature coals from around the world often have rather high extraction yields. It is uncertain whether or not bitumen affecting on petroleum potential and structural evolution of coals. My purposes were therefore to find out the possible interaction between kerogen and bitumen during pyrolysis, and to elucidate the role of bitumen in defining petroleum potential and structural evolution of coals. Furthermore, it is assumed that low rank coals appear to be well suited for feeding the deep subsurface microbes. The products are released as either CO2 or CO that could be substrates for microbial activity. Thus, in this dissertation, I have calculated the loss of CO2 during diagenesis to give the quantitative feeding potential link to deep biosphere, using a mass balance model. To achieve these purposes, at the primary step, the facies variability as well as the molecular compositional changes within the coal band sequence in regard to distinguish the influences of organofacies and maturity need to be clear. Hence, the first aim was to gather information about depositional environment and insights into the plant communities that have contributed to New Zealand coals. Numerous organic-geochemical techniques were used to analyse the free lipids and macromolecular organic matter. Total organic carbon determination (TOC), bulk δ13Corg isotope analysis, the Rock-Eval pyrolysis, pyrolysis- gas chromatography and infrared spectrometry were performed on the original samples and the residue after solvent extraction. The crude lipid extract was separated into fractions that were then analysed by gas chromatography and gas chromatography-mass spectrometry. The obtained data shows that organic matter of New Zealand coals contains mainly terrestrial higher plant material, with a more or less constant background supply of bacterial biomass, deposited in oxidising environment. Angiosperms contributed as the main proportion of the organic matters. Gymnosperms, particularly the Podocarpaceae, Cupressaceae, Taxodiaceae, Pinanceae and Araucariaceae conifer species, still dominated during the Cretaceous. New Zealand coal is classified as mixed gas- and oil-prone. Hydrogen index values increase from 120 to 280 (mg/g TOC) with increasing maturity, which has been explained by the loss of oxygen during diagenesis. A Transformation Ratio of CO2 (TRCO2) has been formulated here in order to quantify the loss of CO2 for any given coal type. It obviously shows CO2 generation is one of the major features of diagenesis that might feed the deep biosphere. In case of study, about 10 to 105 mg CO2 per gram of total organic carbon have been released during maturation from peat to high volatile bituminous. This is equivalent to 0.23 to 2.4 millimoles CO2 per g TOC. For methanogenesis via CO2 reduction, between 0.92 and 9.6 millimoles hydrogen would be required for complete CO2 reduction during diagenesis. Future work must determine if this is feasible or not. The important role of bitumen in defining the petroleum generation potential was elucidated. The presence of hydrogen transfer agents in bitumen helps to stabilize free radicals hence prevents recombination/ repolymerization processes thus preserving the petroleum generating potential in original coals. Specially, second-order reactions between kerogen and bitumen occurred during pyrolysis that reduce the primary gas yield, but increase the potential secondary gas as well as oil yields. Therefore, it is proposed that pre-extraction of source rocks before pyrolysis, especially coals where extraction yields are particularly high, is not recommended. The comparative investigation with previously studied higher rank Carboniferous German coals showed an excellent fit for both pyrolysis and infrared spectrometry data, suggesting that the New Zealand coals can be considered as natural precursors of the German coals. The structural evolution of coals during maturation is firstly characterized by the enrichment of the aliphatic structures in low rank, peat to high volatile bituminous, then decreases with further maturation. This enrichment of aliphatic carbon content in low rank is accompanied by an increase in the average aliphatic chain length. A slightly enrichment of CH3 group is observed in maturity range 0.9- 2.1% vitrinite reflectance. Secondly, during coalification the content of protonated aromatic carbons increases until R0 ~ 1.6%, then decreases with further maturation.
Im Mitteldevon wurde im heutigen Gebiet von Rügen-Hiddensee und der östlich angrenzenden Ostsee eine über 1500 m mächtige Abfolge kontinentaler und rand- bis flachmariner Sedimente abgelagert, die durch 10 Bohrungen einer Untersuchung zugänglich geworden sind. Unterdevon fehlt; die Abfolge lagert mit großer Lücke und diskordant kaledonisch deformierten ordovizischen Schichten auf. Sie geht kontinuierlich in Oberdevon über. Geröll-, Lithoklasten und Quarzkorn-Analysen belegen die Herkunft der Sedimente von einem sedimentär-metamorphen Liefergebiet - den Mitteleuropäischen Kaledoniden im SW bis W des devonischen Rügen-Beckens. Geochemische und petrographische Ergebnisse unterstreichen ihre Ablagerung im Übergang eines aufgearbeiteten Orogens zu einem Kontinentalgebiet im Vorfeld der kaledonischen Hochlage. Faziesanalysen führen zu dem Schluss, dass Sedimentfazies und -zyklizität durch eine materialliefernde Hochlage im SW, variierende Subsidenz, klimatische Variationen (saisonale bis episodische Niederschläge, Austrocknung) sowie durch Transgressionen aus einem marinen Gebiet im SE bestimmt waren. So ergeben sich zwei große Faziesbereiche: (1) terrigene Red-Beds mit Molasse-Charakter – die Old Red-Fazies (ORF) im eigentlichen Sinn; (2) eine rand- bis flachmarine Fazies – die so bezeichnete Litoral-Marine Fazies (LMF). Zwischen beiden existieren Verzahnungen und Übergänge mit transgressivem bzw. regressivem Charakter. Aufgrund einer generellen „Absenkung“ veränderte sich Sedimentationsraum von einer vorwiegend kontinentalen Ebene im tieferen Mitteldevon über einen sandigen Flachschelf am Ende des Mitteldevons zu einem Karbonatschelf im Oberdevon. Diese Entwicklung korreliert gut mit den Phasen des globalen Meeresspiegelanstiegs in diesem Zeitraum. Die sedimentologischen, petrographischen, geochemischen und mineralogischen Analysen erlauben eine detaillierte Rekonstruktion der Ablagerungsmilieus. Das Material der terrigenen Red Beds (ORF) wurde durch ephemere Ströme und Schichtfluten auf eine weite flache Alluvialebene gebracht und auf ephemeren Überschwemmungsebenen sowie distal auf terrigenen Mud Flats und in ephemeren Tümpeln abgelagert. Dabei unterlagen die oberflächennahen Sedimente saisonaler Austrocknung und Evaporation (Bildung von Trockenriss-Feldern, Calcretes, teils Spuren von Gips/Anhydrit). Demgegenüber bezeugen lokal verbreitet auftretende grüne und graue Horizonte mit gehäuften Pflanzenresten und Sporen zeitweilig wasserbedeckte Gebiete und Bedingungen erhöhter Humidität und bevorzugten Pflanzenwuchses (Küstenniederungen). Zahlreiche marine Einschübe, die den SE-Teil des Arbeitsgebietes bereits im Eifel erreichten, und mit der Zeit im zunehmenden Maße auch den Westteil beeinflussten, signalisieren die marginale Lage des Rügen-Beckens zu einem sich im SE anschließenden marinen Ablagerungsraum. Sie führten zu einer zunehmenden Marinität der mitteldevonischen Abfolgen und zur Bildung des zweiten Faziesbereiches (LMF) aus tidal-lagunären und litoralen bis flachmarinen Sedimenten. Phasenweise ansteigende fluviatile Transportkraft führte zur Schüttung gröberer, vorrangig sandiger, seltener konglomeratischer Sedimente und zur Kompensation der Beckensubsidenz, was sich in Abfolgen progradierender Küstenlinien und deltaischen Küstenvorbaus widerspiegelt. Des weiteren führt die intraformationelle Aufarbeitung der Sedimente zur Bildung zahlreicher Intraklasten-Horizonten. Die Klimaproxies signalisieren semiaride Bedingungen in Übereinstimmung mit der paläogeographischen Lage Vorpommerns und Balticas im Devon im südlichen Trockengürtel bis äquatorialen Feuchtgürtel. Mittels der Faziesverteilung, der Sediment- und base level-Zyklizität und der Milieuentwicklung ist es möglich, ein zeitlich-räumliches Faziesmodell zu konstruieren mit Rückschlüssen auf die generelle Entwicklung des vorpommerschen Mitteldevons. Paläogeographisch existieren enge Verbindungen zu den polnischen Devonvorkommen; vorrangig zur Koszalin-Chojnice-Zone (NW-Polen), darüber hinaus in SE’ Fortsetzung vermutlich bis zur Radom-Lublin-Region und dem Heilig-Kreuz-Gebirge. Sie sind an den Südrand des Old Red-Kontinents einzuordnen und wurden in einem perikratonalen, sich nach SE vertiefenden Becken entlang dessen Peripherie abgelagert. Variierende Subsidenz und Mobilität kaledonischer Grundgebirgsblöcke modifiziert die Faziesmuster in diesem Becken. Während die Sedimentation in Südpolen bereits im Unterdevon begann bzw. sich teils kontinuierlich an das Silur anschließt, wurde der vorpommersche Ablagerungsraum erst ab der Wende Ems/Eifel in das Sedimentationsgeschehen einbezogen. So bildete die Rügen-Senke den nordwestlichsten Ausläufer des polnischen Perikratonalraumes. Ihre ursprüngliche Ausbreitung nach Südwesten, Nordwesten und Nordosten ist aufgrund post-devonischer Denudation nicht rekonstruierbar, jedoch wahrscheinlich begrenzt durch das Fennoskandische Hoch im N und einer materialliefernden kaledonischen Grundgebirgshochlage im SW.
The primary objective of this study is to practically apply geostatistical tools that can help to improve an evaluation of groundwater quality for a particular area. The Nam Dinh area, an area of 70 x 70 km2, located in the Southern part of the Red River Delta, was selected as a source for different data sets to be used as case studies. A set of geostatistical tools has thus been applied to the different real data sets which were collected from the coastal Quaternary aquifers in the different campaigns. This gives us a yardstick by which the success of a specific approach can be measured. Throughout the thesis a series of the case studies are, in turn, represented in order to get insight into and an understanding of what various geostatistical tools can do and, more importantly, what their shortcomings are. There are nine different methods of data analyses use in this thesis, which include: (1) Major Ion Comparison, (2) Graphic Plots, (3) Exploratory Statistical Data Analysis, (4) Variogram Analysis, (5) Spatial Estimation Using Kriging, (6) Cluster Analysis, (7) Principle Component Analysis, (8) Multivariate Regionalization Analysis, and (9) Contamination Risk Mapping Using Indicator Kriging. First, major ion comparison and graphic analysis are performed in order to get a general hydrogeochemical view of the collected datasets, before stepping into a further geostatistical approach. By these analyses, various groundwater types are observed and a general hydrochemical trend is visualized using Stiff- and Piper diagrams as well as site maps. The major ion ratios in relation to TDS concentration are compared to investigate the origin of water. Second, a statistical exploratory data analysis is applied to describe the important features of the data by which the character of a specific hydrogeochemical variable might be recognized. Deviations from the Gaussian probability model are detected and appropriate transformations for a formal analysis in geostatistics are selected. Since the Theory of Regionalized Variables (Mathéron 1971; short term: Geostatistics) assumes Gaussian distribution the hydrochemical variables used here are checked for normality. These analyses show that although the data are facing some problems such as outliers and they are very positively skewed at the linear scale, this can effectively be minimized by transforming the data to log-scale. Third, both variogram analyses and Kriging techniques are used to spatially estimate a rectangular 36x36 estimation grid within an area of 70 x 70 km based on the sampled locations (85, 45 and 74 and 38 visited locations for the Pleistocene RS, the Pleistocene DS, the Holocene RS, the Holocene DS, respectively). These estimated values are then used to map the spatiotemporal variability of groundwater quality. In practice, estimation of unknown values and mapping of concentrations of a specific variable can, of course, easily be created by many available software programs. However, error variances are always present in any estimation due to a level of uncertainty, so the reliability of how these estimates could be yielded has also been evaluated in this case study. A critical assessment of all possible variations, tightly related to the seasonal change, directional influence, spatial distribution and prediction error is conducted and concluded. Fourth, Cluster Analysis (CA), Principle Component Analysis (PCA) and Multivariate Regionalization Analysis (RA) are applied to three main datasets of all Quaternary aquifers in the Nam Dinh area to discover the relationships among measured hydrochemical parameters by which we can detect and regionalize major factors which have an impact upon groundwater quality. These approaches are also to overcome the plethora of data that is usually a common problem for any one who has already tackled groundwater data. In this case study both clustering and R mode principal component analyses are thus performed based on the following parameters: The log-transformed concentrations of all measured major ions and of NO3-, NO2-, NH4+, PO42-, i.e. 11 variables from three different datasets of the main aquifers. By cluster analysis three classes of water types, ranging from freshwater to brackish-saltwater types, are typically grouped. Finally, Indicator Kriging (IK) is performed to evaluate the risks of arsenic contamination. The focus of this approach is to assess contamination risk expressed as probability of exceeding threshold- values. The region may thus be subdivided into “safe” and “unsafe” zones on the basis of probability maps which mark contaminated all places where the risk of arsenic contamination exceeds a given threshold for drinking water purpose. By this case study, it is shown that Indicator Kriging is a useful method which has some advantages for many contamination studies. Firstly, it is well known as the non-parametric technique which can be appreciably used when a dataset does not reach normal shape or nearly normal shape as in this situation. Secondly, the outlier problem that often exists in any analysis can be overcome when applying this method. Thirdly, it can be applied in practice to delimit a study area into “safe zone” or “unsafe zone” from which decision-making on the water supply can be decided for the remediation of a contaminated water source or selecting an appreciative source for exploitation. The combined use of spatial (Geostatistics) and multivariate statistical measures have proven to be of major assistance in questions of assessing groundwater quality especially in less sampled regions. A major advantage lies in the possibility of simultaneously creating spatial estimates as well as estimation confidence limits.
The Caribbean is a geologically complex region with several different plate boundary interactions. Geodynamic reconstructions of the northwestern Caribbean region have been particularly controversial in terms of the number of arcs, subduction polarity, and timing of collision. This thesis develops a refined tectonic reconstruction for the northwestern Caribbean based on a review of geological data of Cuba and a regional analysis within the northwestern Caribbean context. With regard to plausibility, significant emphasis was put on the degree and qualitiy of visualization. Three crustal sections across key areas in western, central, and eastern Cuba have been constructed in order to conduct an evolutionary interpretation in three dimensions. Western and central Cuba constitute an orogenic belt resulting from the collision of a mid- to Late Cretaceous volcanic arc - the "Great Caribbean Arc" - with the southern paleomargin of North America. The collision process apparently started in the Campanian, but major north- to northeast-directed thrusting processes at the southern Bahamas margin culminated during the Paleocene. A continous southwest-dipping polarity of the "Great Caribbean Arc", at least from the Aptian-Albian, can be infered from (1) its Late Cretaceous approach towards the North American margin, (2) the magnitude of top to the north directed tectonic transport in the Cuba orogenic belt, and (3) the internal structures of the metamorphic fore-arc assemblages and their evolution on the north side of the arc. An Early Cretaceous southwest-dipping origin of the "Great Caribbean Arc" along the northern fringe of the Chortís Block appears to be in all probability. This concept provides a link between (1) middle Late Cretaceous collision processes along the Matagua suture zone, (2) the Turonian termination of "Great Caribbean Arc"-activity on Jamaica, and (3) the late Campanian onset of collision in the Cuba orogenic belt. The collision of the "Great Caribbean Arc" with the Bahamas margin hampered relative northward motion of the Caribbean Plate from the late Campanian onward. Continued northward push finally resulted in the commencement of north-dipping subduction. Late Cretaceous commencement of north-dipping subduction was accompanied by superposition of oceanic crust and large-scale north-directed gravity sliding on the upper plate, as documented by ophiolitic slide-masses and Maastrichtian olistostromes in eastern Cuba (Nipe - Cristal and Moa Baracoa ophiolite massifs) as well as on Jamaica (ophiolites of the Bath-Dunrobin Complex) and the southern peninsula of Hispaniola. Progress of north-dipping subduction was responsible for the emergence of a Paleocene to Middle Eocene volcanic arc which spanned the northwestern Caribbean along the southern boundary of the Yucatán Basin while the Chortís Block and the Nicaragua Rise were still in a paleoposition to the south of the Maya Block. North-dipping subduction and the associated volcanic arc isolated the Yucatán Basin from its original affiliation to the Caribbean Plate. Relative northward motion of the Caribbean Plate and activity of the Paleogene volcanic arc stopped after the Eocene arrival of thickened oceanic crust of the Caribbean Large Igneous Province at the north-dipping subduction zone. After the late Early Eocene commencement of spreading at the Mid-Cayman Rise, North America - Caribbean relative motion was taken up along the sinistral Oriente Fault with estimated amounts of 800 to 1000 km offset since the Middle Eocene. This transform margin dissmembered the northwestern Caribbean extend of the Paleocene to Middle Eocene volcanic arc. Its eastern bend was uncoupled in the course of this process and may be represented by the Aves Ridge. South-central Hispaniola can be restored to a Middle Eocene position to the south of eastern Cuba, which accounts for an approximate Cenozoic displacement of 200 to 300 km. Therefore, most of the western prolongation of the Oriente Fault must be accommodated at the northern bounding-faults of the southern peninsula of Hispaniola. The proposed synthesis is in clear accordance with the paradigm of plate tectonics, corroborating its capability to incorporate even a complex region like the Caribbean.