This thesis deals with the stratigraphy and brachiopod systematic palaeontology of the latest Devonian (Famennian) to Early Permian (Kungurian) sedimentary sequences of the Tarim Basin, NW China. Brachiopod faunas of latest Devonian and Carboniferous age have been published or currently in press in the course of the Ph.D candidature and are herein appendixed, while the Early Permian brachiopod faunas are systematically described in this thesis. The described Early Permian brachiopod faunas include 127 species, of which 29 are new and 12 indeterminate, and six new genera (subgenera) are proposed; Tarimella, Bmntonella, Marginifera (Arenaria), Marginifera (Nesiotia), Baliqliqia and Ustritskia. A new integrated brachiopod biostratigraphical zonation scheme is proposed, for the first time, for the latest Devonian-Early Permian sequences of the entire Tarim Basin on the basis of this study as well as previously published information (including the Candidate's own published papers). The scheme consists of twenty three brachiopod acm biozones, most of which replace previously proposed assemblage or assemblage zones. The age and distribution of these brachiopod zones within the Tarim Basin and their relationships with other important fossil groups are discussed. In terms of regional correlations and biostratigraphical affinities, the Late Devonian to Early Carboniferous brachiopod faunas of the Tarim Basin are closest to those from South China, while the Late Carboniferous faunas demonstrate strong similarities to coeval faunas from the Urals, central Asia, North China and South China. During the Asselian-Sakmarian, strong faunal links between the Tarim Basin and those of the Urals persisted, while at the same time links with central Asia, North China and South China weakened. On the other hand, during the Artinskian-Kungurian times, affinities of the Tarim faunas with the Urals/Russian Platform rapidly reduced, when those with peri-Gondwana (South Thailand, northern Tibet) and South China increased. Thirty lithofacies (or microfacies) types of four facies associations are recognised for the Late Devonian to early Permian sediments. Based on detailed lithostratigraphy, biostratigraphy and facies analysis, 23 third-order sequences belonging to four supcrsequences are identified for the Late Devonian to Early Permian successions, from which sea-level fluctuation curves are reconstructed. The sequence stratigraphical analysis reveals that four major regional regressions, each marking a distinct supersequence boundary, can be recognised; they correspond to the end-Serpukhovian, end-Moscovian, late Artinskian and end-Kungurian times, respectively. The development of these sequences is considered to have been formed and regulated by the interplay of both eustasy and tectonism. Using the system tract of a sequence as the mapping time unit, a succession of 47 palaeogeographical maps have been reconstructed through the Late Devonian to Early Permian. These maps reveal that the Tarim Basin was first immersed by southwest-directed (Recent geographical orientation) transgression in the late Famennian after the Caledonian Orogeny. Since then, the basin had maintained its geometry as a large, southwest-mouthed embayment until the late Moscovian when most areas were the uplifted above sea-level. The basin was flooded again in late Asselian-Artinskian times when a new transgression came from a large epicontinental sea lying to its northwest. Thereafter, marine deposition was restricted to local areas (southwestern and northwestern margins until the late Kungurian, while deposition of continental deposits prevailed and continued through the Middle and late Permian into the Triassic.

The Cocos Gap is a deeper portion, or saddle, of the Cocos Ridge and forms part of the western boundary of the Panama Basing It is probably typical of saddles within most submarine ridges, In order to determine the mechanisms controlling sediment dispersal, the nature and sources of the sediments at 23 core locations were defined by hydrodynamic size separation (> 63, 2- 63, <2 micron) and microscopic or X-ray diffraction analysis of the individual fractions. In addition, calcium carbonate, organic carbon, opal and quartz determinations were made for the total sediment. The silt sized fraction was resolved into eight textural modes, The coarse modes reflect the progressive breakage and winnowing of the corase fraction (foraminifera) under the influence of bottom currents and gravity. Above 2000 m mechanical breakdown, winnowing and relocation by bottom currents mask the effects of depth related dissolution of the carbonate fraction, Intermediate modes in general represent a transitional facies with both biogenic and terrigenous influences, while the finest modes characterize a distal regime of clay deposition, The clay fraction is amorphous material with very low percentages of well crystallized clays. Three main sources and transport paths were recognized, including one associated with the circulation of the Panama Basin. Sedimentation within the Gap is controlled by local processes, predominantly the interaction between tidally induced intensification of bottom water flow and directional (thermohaline) flow. The steep' ness of the sea floor slope is a major factor controlling the efficiency of winnowing of the sediment away from certain higher elevations (biogenic source areas) to the sheltered parts and flanks of the ridge. Superimposed upon this sediment dispersal is the influx of terrigenous material carried by directional bottom currents that operate as postulated upper and lower contour currents along the flanks of the ridge. The crest of the Cocos Gap acts as a catchment area for the biogenic components, while the adjacent more sloping region, the sub-plateau, acts as a source area. The extreme breakage of the foraminifera is most likely a function of the tidally induced intensification of the bottom water flow, characteristic of many shallow ridges, and is probably most significant in the subplateau. Hydrographic data indicates that there is no significant transport of bottom water across the Cocos Gap into the Panama Basin, but downslope transport of carbonate and siliceous fragments and minerals from the Gap into the basin is associated with cyclical tidal bottom water flow. / Graduation date: 1976

Low copy number anonymous nuclear loci were used to search for species markers in four species of Klamath Basin suckers. We sequenced 28 randomly chosen loci representing 10,421 bp; 21 loci were similar to sequences in GenBank. Eight fixed sequence differences were found among Klamath species. Locus 120 contained rare but diagnostic markers for Deltistes luxatus and for Catostomus rimiculus. Locus 4 also contained three rare but unique sites in Catostomus rimiculus. No sequence differences were found between Chasmistes brevirostris and Catostomus snyderi. Loci 4 and 120 exhibited allele frequency differences between Rogue River C. rimiculus and all Klamath Basin suckers. Genotype BB of locus 4 was a fixed diagnostic marker and genotype BB of locus 120 was a frequency dependent marker for Rogue C. rimiculus. Although Klamath suckers represent three genera, very limited variation was found among 10,431 base pairs. We examined phylogenetic patterns of five loci in eleven catostomid genera and 25 species to determine if the homogeneity in the Upper Klamath Basin was due to massive hybridization and introgression or to retention of ancestral sequences. Two loci with no similarity to GenBank sequences (non-coding loci) and three loci with substantial similarity to GenBank sequences (coding loci) gave similar results, providing support for various subfamilies and tribes, more support for eastern genera and little support for western genera. Each locus was a mosaic of species or population markers, sometimes providing discriminatory power for allopatric populations of a species, such as C. macrocheilus, while not discriminating other species. Upper Klamath Basin species were noteworthy in their lack of autapomorphies, but had similar numbers of derived informative sites as other catostomins. Upper Klamath Basin species consistently shared ancestral or equivocal informative sites either with moxostomatins or a variable group of western species and shared derived sites with other western species, especially C. occidentalis. The data suggest that Upper Klamath Basin species have retained a largely ancestral genome at these loci. Thus, the failure of this technique to uncover significant variation in Upper Klamath Basin species may be a reflection of their plesiomorphic genome at these loci and not necessarily hybridization. / Graduation date: 2004

In the past decade considerable research in several disciplines has been oriented toward the design of optimal capacity expansion plans for water resource systems. The emphasis of most of these efforts has been directed toward minimization total cost outlays in project planning. This focus somewhat limits the full applicability of the optimal capacity expansion solutions since it is believed that the criteria of economic efficiency is not well addressed in this mode. This study explores the merits of scheduling water resource project facilities on the basis of anticipated economic benefits provided, an approach needed only infrequently in the systems engineering literature. Using the Umatilla River Basin in Northeast Oregon as a case study example, the facilities (and their alternatives) of a previously planned federal water resource development project in that area were carefully analyzed with respect to the magnitude and timing of anticipated benefits and costs. Irrigated agriculture and fishery development/enhancement benefits were the two principal purposes of the project considered. In addition, benefits arising from flood prevention, municipal and industrial water supply, and erosion control were also integral to the original overall evaluation. The design of the research was to first implement a basic scheduling model in the context of the case study area and then to explore the ramifications of exchange-theoretic and distribution-theoretic criteria on the timing of facilities and the ultimate allocation of water among purposes. The model implemented was aimed at maximizing the present value of net benefits inherent in an optimally timed set of facilities subject to an annual budget constraint. Having designed the model along integer programming lines, three different solution techniques were explored in order to realize a desirable level of efficiency in basic model solution. It was found that reasonably efficient solutions could be obtained. By optimally timing the facilities it was found that the total present value of net benefits of the project could be significantly enhanced when compared to the original schedule proposed in the project planning documents. Of even greater interest is the issue of incorporating into the planning process (and specifically into the capacity expansion mode of planning) considerations of tradeoffs or exchanges between project beneficiaries. Such exchanges and other distributional criteria can affect and be affected by the selection and timing of project facilities within an overall project design. These interrelationships are explored paying particular attention to the way in which exchanges of water (via water rights transfers) could establish higher levels of benefits in future years. Noneconomic exchange processes such as the enforcement of extant property rights relating to water resources are another issue which complicated the process of water planning. Such distributional criteria are difficult to incorporate into the capacity expansion mode of planning analysis. However, ways are explored by which the basic model may be modified and used by decision makers in order to take account of more realistic problems in water resource planning for individual river basins. / Graduation date: 1981 / Partially funded by the U.S. Dept. of the Interior as authorized under the Water Research and Development Act of 1978. / Final technical completion report for project no. A-046-ORE to U.S. Dept. of the Interior.

Detailed subsurface structure contour maps and cross sections have shown the northern Los Angeles basin to be underlain by a south facing monocline that is complicated by secondary faults and folds. The monocline forms a structural shelf that marks the northern boundary of the Los Angeles central trough. The monocline and associated structures are called the Northern Los Angeles shelf. Isopach maps show that during the Miocene, the predominant structural style was extension. Thick accumulations of volcanic and volcaniclastic rocks, controlled by normal faults, had a very different depositional pattern than during the Pliocene. At approximately the beginning of the Pliocene extension changed to compression resulting in the reactivation of the Miocene normal faults in a reverse sense and the beginning of the formation of the monocline and secondary structures. Thick growth sequences were deposited to the south of the growing monocline toward the present day Los Angeles central trough. Fault-bend and fault-propagation fold models are inadmissible solutions to explain the growth of the monocline. A basement-involved shear model may explain some of the details of the secondary structures. Analysis of the Pliocene growth strata shows that the monocline and secondary structures, the South Salt Lake, the East Beverly Hills, and the Las Cienegas anticlines, all began to form near the beginning of the Pliocene. All of the secondary structures became inactive prior to the Upper Pico during the Late Pliocene. Thick accumulations of Upper Pico growth strata attest to continued monoclinal folding after the secondary structures became inactive. The growth strata record both the structural growth and the shortening associated with growth and therefore allow the dip of the monocline causing fault or shear zone (the Monocline fault) to be calculated. In the East Beverly Hills area, the growth strata yield a dip of 61°. At Las Cienegas the dip of the Monocline fault is 62°. These dips are maximum values based on the assumption the growth strata record all shortening. The fault slip rates for the Monocline fault are similar in both areas, 1.1-1.2 mm/yr in the East Beverly Hills and 1.3-1.5 mm/yr. in Las Cienegas. The resulting horizontal convergence rates are also similar, .5-.6 mm/yr and .6-.7 mm/yr respectively. The Quaternary marine gravels have been deformed into a broad east-west trending fold, the Wilshire arch. Elastic and non-elastic methods of modeling the blind fault (Wilshire fault), over which the deformation occurred, yield much greater shortening rates than for the Pliocene. The non-elastic method involves modeling the arch as a fault-bend fold. This model predicts a 15° north-dipping thrust with a slip rate of 1.5-1.9 mm/yr and a horizontal shortening rate of 1.4-1.8 mm/yr. The elastic method involves matching the observed deformation to that produced on the free surface by slip on a fault in an elastic half-space. The elastic dislocation model predicts a right-lateral reverse slip solution with an oblique-slip rate of 2.6-3.3 mm/yr. This solution yields a horizontal shortening rate of 1.4-1.8 mm/yr. These higher shortening rates suggest that there was a marked change in tectonic style at the end of the Pliocene from high-angle faulting and tectonic subsidence to shallow faulting and uplift. / Graduation date: 1994

Thesis (M.S.)--Oregon State University, 1982. / Typescript (photocopy). Some maps folded in pocket. Includes bibliographical references (leaves 156-169). Also available via the World Wide Web.

The Volta Basin covers most of the major food producingdistricts of Ghana. Thus said, it is considered as the foodbasket of Ghana. This perception underscores the need toprotect the basins bio-physical environment and resource base.This concern has been mirrored by several initiatives both interms of policy and planning that aim at improving themanagement of the basin’s resource base to enable itspeople depend on it in meeting their livelihoods. Like mostcommunities that lie in the lower reaches of the Volta, thepeople of the South Tongu District have been brought under theimpact of the dam. Even though no extensive study has yet beenconducted to establish the extent of the dam’s impact inthe district, it is widely believed by the locals thatlivelihoods have been impacted by environmental changes. Keycomplaints include, amongst others, tree cover depletion,decline in soil fertility, poor agricultural productivity, lowrainfall and bush fires. At the district level some steps havebeen taken in the form of projects and programmes to addresspoverty and resource management issues, while others areunderway. This study seeks to contribute to the on-goinggeneral discussion concerning poverty and environmentalmanagement in the basin by presenting some perspectives fromfour villages, namely, Torsukpo, Agbogbla, Akato and Alesikpein the South Tongu District. From two perspectives, thesecommunities are considered as homogenous: (i) they are allpredominantlyeweswith respect to ethnic composition, and (ii)subsistence farming features as a key occupation in all thecommunities. Among the range of issues identified in thedistrict, the study discusses mainly conservation (with respectto tree planting), bush fires and co-operative management. Ittreats these issues with focuses on key socio-cultural factors.In the examination of these issues institutional matters suchas tenure are seen as central players in resource managementand are thus given attention. While information gathered hereincontributes generally to deepening knowledge on the prevailingproblems, some recommendations are also offered as possiblesteps to improving resource management and livelihoods in theDistrict. <b>Key words:</b>environment; natural resources; lower volta;local people; livelihood

El comportament hidrodinàmic de les aigües subterrànies en conques intramuntanyoses ve condicionat principalment per la geologia, i especialment pel context estructural i els materials sedimentaris que reomplen la conca. L'estudi d'aquestes àrees requereix un enfocament a gran escala per poder determinar les zones de recàrrega i descàrrega dels diferents sistemes de flux que conformen els recursos hídrics de la zona. Aquestes zones solen estar afectades per un fort desenvolupament humà que pot donar lloc a una modificació de la quantitat i la qualitat de l'aigua subterrània de diferents formes. En aquest sentit, en conques intramuntanyoses és un aspecte clau entendre la importància de la geologia i de les pressions humanes en el flux d'aigua subterrània per arribar a assolir una gestió correcta dels recursos hídrics, així com per assegurar llur disponibilitat a llarg termini. En aquesta tesi s'ha estudiat la depressió de la Selva com a un cas paradigmàtic on té lloc una important pressió sobre els recursos hídrics subterranis. Per tal d'estudiar el paper hidrogeològic que juguen les falles regionals en conques intramuntanyoses, en primer lloc, s'ha realitzat un model hidrogeològic conceptual a partir de la modelització del flux subterrani. Per fer&#8208;ho, s'ha dut a terme una simulació d'una zona de falla subjacent a una formació al&#8729;luvial, on la falla pot recarregar o drenar l'aqüífer al&#8729;luvial. S'han considerat diferents valors de permeabilitat per la zona muntanyosa, la zona de falla i els materials sedimentaris, així com diferents gruixos de falla i condicions de contorn. Els resultats mostren que es poden produir fluxos verticals ascendents i descendents a la part superior de la zona de falla degut a l'acció de la formació al&#8729;luvial, i fins i tot a través del sòcol, influenciant per tant la recàrrega dels materials sedimentaris de la depressió. En segon lloc, s'ha caracteritzat el sistema hidrogeològic de la depressió de la Selva mitjançant mesures del nivell piezomètric i dades hidroquímiques e isotòpiques (&#948;18O, &#948;D) al llarg de diverses campanyes de camp amb un doble objectiu: (i) caracteritzar un sistema hidrodinàmic on els elements tectònics juguen un paper important en la hidrodinàmica subterrània, i (ii) descriure la influència de l'explotació d'aigües subterrànies en la hidrodinàmica del sistema. Els resultats piezomètrics han posat de manifest la relació existent entre les formacions situades a les zones de muntanya que envolten la depressió i els materials sedimentaris que rebleixen aquesta. Les zones de falla tenen un efecte directe en la recarrega, permetent l'existència de fluxos verticals ascendents des del sòcol cap a diferents aqüífers sedimentaris. Les dades hidroquímiques i isotòpiques han validat aquestes observacions. En aquest sentit l'ió fluor (< 15 mg/l) i nitrat (< 217 mg/l) han estat usats com a traçadors dels fluxos profunds i superficials respectivament i han permès posar de manifest l'efecte dels bombejos en la distribució de les línies de flux. La composició isotòpica de la molècula de l'aigua (&#61540;18OH2O, &#61540;D) ha evidenciat canvis estacionals en les aigües captades pels pous posant de manifest l'existència de dos sistemes de flux: un sistema de flux regional amb llargs temps de trànsit i originat a les zones circumdants més elevades, i un sistema de flux local recarregat a la zona de la depressió. Els dos sistemes contribueixen de manera diferent als recursos hídrics que s'estan explotant, i la seva aportació específica defineix el potencial de la depressió per una explotació sostenible a llarg termini. S'han caracteritzat les aigües des d'un punt de vista hidroquímic a partir de la composició en elements majoritaris, minoritats i traça (fluor, brom, liti, TOC) i de dades isotòpiques (&#61540;18OH2O, &#61540;D, triti, &#61540;34SSO4, &#61540;18OSO4). Aquesta caracterització ha permès una descripció acurada dels processos geoquímics que defineixen les fàcies hidroquímiques de l'aigua subterrània al llarg de la depressió de la Selva. Així, s'han definit dos sistemes de flux regional i diferents qualitats de l'aigua associada a la recarrega local, i alhora s'ha corroborat el model hidrogeològic conceptual de la depressió de la Selva. Des d'un punt de vista regional, a la depressió de la Selva el control estructural defineix sistemes de flux locals, intermitjos i regionals, els quals son responsables de la hidrodinàmica a gran escala, fins al punt que aquests son responsables de la recuperació dels descensos del nivell piezomètric després del període de màxima extracció (estiu). A la zona d'estudi, l'origen de la recarrega, a escala regional, és atribuïda a la serralada Transversal, a la zona més septentrional de la conca, i a les Guilleries, especialment a la zona oest. Aquests sistemes hidrogeològics impliquen un flux vertical ascendent des del sòcol que recarrega els nivells aqüífers neògens de la depressió. Els sistemes de flux locals i intermitjos s'originen a la pròpia depressió o a les zones circumdants més properes, els quals estan menys afectats per les zones de falla. La pressió antròpica crea una barreja entre els diferents sistemes de flux modificant la qualitat de l'aigua al llarg de l'any. Els resultats d'aquest estudi mostren que en conques intramuntanyoses per obtenir una caracterització integrada del sistema hidrogeològic i el coneixement necessari per formular estratègies específiques cap a una gestió sostenible dels recursos hídrics, i en concret a la depressió de la Selva, és necessari: i) la utilització de diferents metodologies per abordar l'estudi d'aquests tipus de sistemes hidrogeològics. Així, en el present treball primerament s'aborda des de la caracterització de camp fins a la modelització numèrica passant per l'estudi de nivell piezomètrics i dades hidroquímiques e isotòpiques; ii) caracteritzar l'evolució piezomètrica de les diferents formacions geològiques juntament amb les característiques hidroquímiques/isotòpiques i els processos geoquímics relacionats que defineixen les mostres d'aigua, i per tant, cada un dels extrems de barreja de la recarrega (local, intermitja i regional) que participen en el conjunt del sistema de flux; iii) finalment, identificar les pressions humanes, fins i tot en els sistemes a més gran escala, com una verdadera alteració al comportament natural. Aquesta tesi defineix els sistema hidrogeològic de la depressió de la Selva com a exemple de funcionament hidrodinàmic sota pressions antròpiques aplicable a altres conques intramuntanyoses. Aquest coneixement és necessari per formular estratègies de gestió dels recursos hídrics des d'un punt de vista quantitatiu i qualitatiu, com a eina indispensable per satisfer la demanda lligada a una millora socioeconòmica sense produir un empitjorament de la qualitat ambiental a llarg termini. / Groundwater hydrodynamics in range&#8208;and&#8208;basin areas are essentially determined by their geology, including the tectonic structure and the basin sedimentary infilling. Their study requires a large&#8208;scale approach to determining the location of the recharge and discharge areas of each flow system providing the basin with water resources. Furthermore, most of these areas have undergone heavy human development that can modify groundwater quantity and/or quality in different ways. Understanding geological and human influences on groundwater flow in these areas is a key aspect in achieving an adequate water resources management and therefore its future availability. In this dissertation, the Selva Basin has been studied as a paradigmatic case of a range&#8208;and¬basin area with severe human pressure on its groundwater resources.A conceptual hydrogeological model emphasizing the role of the main fault zones has been developed and tested using numerical flow modeling as a first step. Groundwater flow has been simulated in a range&#8208;and&#8208;basin area affected by a significant fault zone, which may drain or recharge an overlying alluvial aquifer. Various hydraulic conductivity values for the range rocks, the fault¬zone, and the sedimentary infilling of the basin are considered, as well as different fault&#8208;zone widths and boundary conditions. The results show that upward and downward fluxes develop in the upper part of the fault zone controlled by the action of the alluvial aquifer, and even through the basement floor, which influence the recharge of the sedimentary infilling of the basin.Second, the Selva range&#8208;and&#8208;basin hydrogeological system is described using potentiometric, hydrochemical, and isotopic data (&#948;18O, &#948;D) taken from different field surveys, in order to achieve a twofold objective: (i) to describe a hydrogeological system in which tectonic elements play a significant role in the flow dynamics, and (ii) to show the influence of groundwater exploitation on the hydrodynamics of the system. Hydraulic head data indicate the relationships between the geological formations in the range areas and the sedimentary infill of the basin. In this context, fault zones and a fracture network have a direct effect on the recharge, and allow an upward vertical flow from the basement to the sedimentary aquifers. Hydrochemical and isotopic data support this observation. The use of fluoride (up to 15 mg/l) and nitrate (up to 217 mg/l) as tracers for the contribution of deep and shallow flow systems respectively provides a detailed portrait of the effects of pumping on the flowpath distribution. Isotopic data depict seasonal trends in groundwater captured by wells. Two distinct flow systems are differentiated: a regional, large&#8208;scale, long residence time system, originating in the surrounding ranges, and a local flow system constituted by infiltration in the lower areas of the basin. The two systems contribute differently to the resources that are withdrawn, and their specific contributions define the potential for sustainable future water exploitation in the basin. The final part of this hydrogeological study is a more specific description of the geochemical processes that determine the hydrochemical characteristics of groundwater across the Selva basin, based on the interpretation of major, minor and trace elements (such as fluoride, bromide, lithium, TOC, and their ratios to some major elements), and isotope data (&#61540;18OH2O, &#61540;D, tritium,&#61472;&#61540;34SSO4,&#61472;&#61540;18OSO4). It defines two different regional flow systems and different water qualities of local recharge anduses this specific data to corroborates the overall hydrogeologic conceptual model for the Selva range&#8208;and&#8208;basin area. From a methodological perspective, this chapter explores the use of minor elements and isotopes in the interpretation of regional scale system hydrodynamics. It also discusses their use as tracers of the distinct ground water flows originating in distinct recharge areas and influenced by an intricate tectonic setting. The results of this dissertation describe the flow system of the Selva basin. In this basin, structural control defines the local, intermediate and regional flow systems responsible for the large&#8208;scale hydrodynamics of the basin and, more importantly, the recovery of drawdown after the main withdrawal period (summer). The origin of the recharge of the large&#8208;scale, regional flow systems is assigned to the Transversal range on the northern side and to the Guilleries range, especially in the western part. These hydrogeological systems include a groundwater flow within the basement and an upward vertical recharge from the basement to the overlying Neogene sedimentary layers. The local and intermediate flow systems originate in the basin itself or in the less&#8208;elevated surrounding ranges, and the fault system has a minor effect on their flowpaths. Human development modifies the flow paths mixing the different flow systems and changing the water quality along the year seasons. From a broader point of view, this highlights the value of using different methodological insights in the study of these hydrogeological systems, as well as addressing the problem of water management in complex geological environments. First, it presents the outcome of various methodologies ranging from field work to numerical modeling, together with the analysis of hydraulic head, hydrochemical and isotopical data. Second, it shows the relevance of potentiometric evolution in different geological settings, and the treatment of the hydrochemical/isotopic features and related geochemical processes that define groundwater samples and therefore each of the recharge end&#8208;members (local, intermediate, and regional) that participate in the overall flow systems. Finally, it identifies the effect of human pressures even on large&#8208;scale flow systems, as true alterations of natural behavior. The recognition of these effects, together with an integrated characterization of the hydrogeological system, provides the necessary knowledge for formulating specific strategies for assessment focusing on sustainability of water resources management in these geological contexts. In specific terms, these strategies must be based on the importance of the groundwater flow terms in the water balance for a given hydrological basin. These terms are usually overlooked, yet they play an important role, especially when groundwater resources from deep confined (or leaky) aquifers are exploited. In the case of the Selva basin, identifying this contribution is fundamental in establishing potential future exploitation rates that further socio&#8208;economic developments may generate. This dissertation shows the scope of several approaches to describing this term in the water budget in range&#8208;and&#8208;basin areas in order to determine the availability of water resources therein, as a first essential step towards sustainability.

During the Late Pliocene to Middle Pleistocene Ages, sediments of the study area were deposited in the intra-slope salt withdrawal basin where sand-prone sediments deposited as turbidite lobes and channel fills are the main reservoirs of the Northern Gulf of Mexico. The main purpose of this study was to identify and characterize these sand-prone sediments. Sequence stratigraphic analysis of well logs, biostratigraphic data, and 3-D seismic data provided a chronostratigraphic framework of the study area, within which seismic facies analysis was carried out. Each sequence was subdivided into separate seismic bodies characterized by specific amplitude, coherence of reflectors, and shape of reflectors. The descriptions of each seismic facies combined with well logs were compared with turbidite facies models to infer their geological information. Five turbidite elements were identified: depositional channel fills and overbank deposits, erosional channel fills, turbidite lobes, mud turbidite fills and sheets and hemipelagic and pelagic drapes. Depositional channel fills are usually deposited in lower parts of interpreted sequences, surrounded by shale-prone overbank deposits. The lateral variation of these turbidite elements was revealed by horizon slices, in which depositional channels are generally trending NE-SW or NNE-SSW with elongated sinuous forms. Well logs indicate that depositional channel fills usually consist of bell or cylinder type sand-prone sediments. Turbidite lobe was found only in the 1.1-0.8 Ma sequence, in which it laps out onto the underlying sequence boundary and shows high-amplitude and a high-coherence of mound shape. This facies is interpreted as sand-prone, but wells available penetrated only the marginal parts of this facies and showed poor reservoir qualities. Horizon slices could partly reveal its lapout boundary due to the limitation of vertical seismic resolution. Mud turbidite fills and sheets are the most dominant turbidite facies, which usually occurred in the upper parts of sequences and overlain by hemipelagic and pelagic drapes. Hemipelagic and pelagic drapes were deposited very widely, wrapping down the previous topography with consistent thickness throughout the basin. Erosional channel was observed only in the 0.8-0.7 Ma sequence where it cut into the underlying sequence and was filled by shale-prone sediments. Depositional channel fills and turbidite lobes are the main reservoir facies in the study area. Seismic facies analysis using vertical seismic sections and horizon slices combined with lithology data made it possible to identify and systematically describe these sand prone turbidite elements in intra-slope salt withdrawal basin.

Understanding the nature of mud volcanism, mechanisms of formation, types of eruptions and their relationship to the hydrocarbon systems provides important information about subsurface conditions and geological processes within the South Caspian Basin. A 2D seismic grid in southeastern offshore Azerbaijan is used to define the areal distribution of mud volcanoes and to make a classification of the mud volcanoes based on characteristic seismic features. As a result detailed database for each determined mud volcano is constructed. Analysis of different parameters from this database shows that there is a high concentration of mud volcanoes at the southern part of the study area. It is coincides with the distribution of the subsurface structures within the basin. Mud volcanoes with low relief (several tens of meters) are mainly concentrated in the northeast. Conversely, mud volcanoes with large vertical relief (greater than 200 m) are clustered in the southwest part of the basin. Mud volcano development in the South Caspian Basin is generally linked to faults, which in some instances are detached at the basement level. By using interpreted seismic surfaces it is possible to determine relative time of mud flows from the mud volcanoes. Timing of mud flows reveals to the actual activity of the mud volcanoes and it gives valuable information about possible mechanism of mud volcanism within the South Caspian Basin. Previous studies of the onshore mud volcanoes in Azerbaijan and the results from current work conclude that mud volcano formation within the South Caspian Basin is mainly controlled by tectonic forces and overpressured sediments. Mud volcano activity is not always related to the Maykop organic reach shale succession. It can occur at shallow depths by pressure breakthrough from any stratigraphic zone.