A seismic stratigraphy study was conducted to develop a stratigraphic framework for Pliocene-Pleistocene sediments in the Ganal area, Makassar Strait, Indonesia. The study area, physiographically located in the continental slope of the offshore Kutai basin, is very attractive for deep water sequence stratigraphy analysis. The sediment interval exhibits a series of geologic features of deep water sedimentation such as a submarine fan associated with canyons and channels-levees complex. Analysis of over 4000 km of multichannel seismic data serves to detail documentation of such features and the stratigraphic evolution of the area.

On the basis of their termination patterns, two types of significant stratigraphic surfaces, unconformity and flooding surfaces, can be identified as seismic boundaries on the seismic sections. The unconformity surfaces can be recognized by erosional, truncation, and onlap termination patterns. The distribution of these surface can be correlated in the area from the slope to the basin floor, which is commonly associated with scour channels. The flooding surfaces can be recognized by downlap termination patterns of the younger layers into the older strata below. Both of these surfaces provide important information to reveal the depositional history of the deep water sedimentation in the study area.

Regional seismic profiles indicate that the Pliocene-Pleistocene sediments were deposited in the slope to basin floor setting, from the west to the east respectively. The structural and stratigraphic analysis suggests that this basin configuration strongly influenced the distribution and thickness of the seismic sequences and stratigraphic development of the Pliocene-Pleistocene sedimentary succession. Isochron maxima correspond to the depocenters that are close to sedimentary pathways and are associated with submarine channels and canyons. The isochron patterns show that depocenters and sediment pathways during deposition of the Pliocene-Pleistocene interval coincide with regional basin setting.

Six seismic sequences have been identified within the Pliocene-Pleistocene interval. Each sequence consists of lowstand deposits that can be recognized by its seismic facies units. The seismic characteristics vary from sequence to sequence as well as within lowstand system tracts. Lowstand features including submarine canyons, channels, and fan lobes have been identified and mapped. Identification of these features substantially reduces the reservoir risk associated with deep water depositional environments.

Superimposed of the canyons, channels, and fan lobes in the study area was presented in the composite map and served as good model and unique example for deep water sedimentation. Finally, a depositional model of lowstand deposits for the study area has been established and may play an important role in future exploration and development in this region and elsewhere in the world.

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Anisotropy in Earth materials often leads to unexpected geophysical responses that can not be anticipated from simple isotropic models. In this study, I investigate the effect of lateral anisotropy on transient CSEM responses of a conducting half-space excited by a horizontal loop. This study involves the mathematical solution, modeling, and interpretation of the behavior of the transient CSEM response.

Mathematical solutions are derived which describe the behavior of current density components and the vertical component of magnetic field within the Earth. These are developed from Maxwell equations and boundary conditions to model the smoke ring in a uniaxially half-space.

In this thesis, a pair of forward modeling computer programs have been developed to investigate the effect of fractures on the transient CSEM response. One program computes the theoretical response, as a function of time, of a horizontally anisotropic half-space to a sudden switch-off of electric current excited by a horizontal loop. The other program computes the elliptical diffusion smoke ring in a horizontally anisotropic half-space to a sudden step-on of electric current excited by the horizontal loop.

Electromagnetic boundary value problems based on Maxwell’s equations are solved analytically in the frequency domain. The vertical magnetic field component and the two horizontal current density components are then transformed into time domain by means of the Chave and Tilman methods, respectively. Modeling elliptical diffusion smoke rings is done for two cases, namely (fractures more conductive than the matrix) and (fractures more resistive than the matrix).

In the theoretical results, a "paradox of anisotropy" is observed in transient CSEM in which the field is more pronounced along the strike of relatively conductive fractures. This is opposite to what one might expect based on the isotropic theory.

Smoke rings are discussed in this thesis. They take circular loops in a uniform isotropic half-space while they take an elliptical shape in a horizontally anisotropic half-space, diffusing downward and outward through the conducting medium. The transient behavior of the rings are characterized in detail.

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The Bone Spring Formation is a series of interbedded siliciclastics and carbonates that were deposited in the Delaware Basin during the Leonardian (Early Permian). It consists of the First, Second and Third Carbonate and the First, Second and Third Sandstone, as well as the informally named Avalon Sandstone. The Second Bone Spring Sandstone, the focus of the study, can be subdivided into four distinct sand bodies separated by pelagic zones. These sands are designated the A-D Sands. The depositional patterns of the Bone Spring Formation are reflective of the underlying structure that resulted from compression during the Mississippian and Pennsylvanian.

The Second Bone Spring Sandstone (specifically the C Sand) is essentially a dolomitic, coarse siltstone that is composed of facies reflective of deposition by turbidity currents in a slope fan environment. The midfan, levee/overbank and hemipelagic environments of deposition identified in the Second Bone Spring Sandstone in this study are consistent with those of the typical slope fan of Walker (1978). The slope fans of the C Sand are confined by north-to-south trending reverse faults, which inhibit lateral migration of both the fans and the channels within them.

The A-D Sands are correlatable throughout the study area but thicken in the underlying structural lows. These thicker sands are lobate in plan view and are located adjacent to, rather than directly on top of, underlying thick sands. This is likely a result of differential compaction of underlying sediment and serves to further confine the fans.

The sediment comprising the Second Bone Spring Sandstone was likely transported through basinward migration of sand dunes in an arid environment during relative sea level lowstands. Periodically, brief rises in sea level choked off sediment supply allowing hemipelagic material to be draped over underlying sands. With sea level fall, sands were again deposited in the tectonic sub-basins.

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Inversion of normal faults at different burial depths is studied using physical models constructed with rock and deformed at confining pressure. Models consist of a 1-cm thick limestone layer above a fault dipping 70 degrees in a rigid medium, and are subjected to a two-stage deformation path of layer-parallel extension followed by coaxial contraction. To investigate the effects of burial depth and relative ductility on kinematics of inversion, five model suites were run in which confining pressure and recovery magnitudes were varied. In all models, a normal fault forms in the limestone during extension. Subsequent inversion is accommodated in the limestone by reverse slip on the normal fault, creation and movement along new reverse faults, and distributed fracturing and folding. The relative contribution of these mechanisms depends on the relative ductility of the rock and magnitude of inversion. Reverse slip on the normal fault and distributed fracturing occurs during early stages of inversion and new reverse faults form at intermediate stages. During late stage inversion, strata with low mean ductility shorten primarily by reverse slip on the pre-existing normal fault, whereas strata with high mean ductility shorten by continued slip on reverse faults.

Evidence for inversion is provided by superposed fracture fabrics in the footwall at early stages (<35% recovery), fracture and fault fabric in the upthrusted wedge at intermediate stages (35% to 100% recovery), and extensive localized cataclasis and relatively thick fault zones with small net displacement at late stages of inversion (>100% recovery). This change in fracture fabric during inversion could lead to an overpressured footwall in natural inversion structures. Reverse reactivation of the normal faults may occur during coaxial contraction even though such faults are unfavorably oriented assuming typical rock friction behavior and a homogeneous stress state. Localized reverse slip on normal faults is favored when strata display low ductility and less favored when strata work-harden during extension, however, the models show that the final inversion geometry is dependent on the ductility during both phases of deformation. Even a fault that is work-hardened during extension can reactivate if the ductility during contraction is low enough.

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Sorption processes are known to be the controlling factors in mobility of organic contaminants in soils and sediments. It has been generally assumed that the organic matter fraction is the dominant sorbent of organic compounds. Mineral-organic interactions were thought to be negligible or nonexistent. Recent studies have shown that the mineral contribution in sorption of Polycyclic Aromatic Hydrocarbons (PAH) has been underestimated.

Sorption mechanisms between minerals and PAH are poorly understood. This study followed a mechanistic approach to confirm suspected specific mineral-PAH interactions. The focus was on the sorption of pyrene to three clay sorbents, a soil clay fraction and two reference clay standards, in the presence of a competing solute, pyridine. Past studies have shown that pyridine can be directly coordinated to exchangeable cations; therefore, it can theoretically compete with pyrene for specific sites. Equilibrium sorption isotherms were modeled with the Freundlich Equation using nonlinear regression.

Results showed that pyrene adsorbed to highly charged and polar phyllosilicates minerals. Macroscopic sorption experiments revealed a trend of increased pyrene sorption with increase in cation exchange capacity (CEC) of sorbents. Competitive behavior was observed when pyridine was introduced in binary solute sorption experiments. Pyridine decreased the amount of pyrene adsorb by all three clay sorbents. Competition was much more significant in the reference clay standards with the lower CEC. These results suggest that a specific interaction between the aromatic rings in pyrene with the exchangeable cations on the clay surface may be present, suggesting that sorption processes can be controlled by the formation of cation-pi bonds.

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Many aquifers and petroleum reservoirs are hosted by clastic sedimentary rocks, which typically possess complex internal structures and are hierarchically organized at various scales of complexity and length. Although sedimentary patterns are well known and their hydraulic properties of the composing lithologies, i.e., porosities and conductivities, are intrinsically coupled, they are rarely utilized in flow and transport simulations. The purpose of this study is to integrate sedimentological information and modeling by using a stratigraphic simulator to generate input for a new flow simulator. The stratigraphic simulator provides maps of the distribution and orientation of the sedimentary units, which is used to align tensor properties such as hydraulic conductivities. The resulting fully three-dimensional nine-component conductivity tensor is suitable to approximate subnode-scale properties like grain fabric, small-scale bedding or lamination, or fractures. Flow-restricting interfaces can be applied to mimic thin but low-permeable units. The flow simulator allows the assessment of potentiometric heads, velocities, flowline and advective front geometries, as well as the upscaling of conductivity of complex multidimensional model domains, using different driving head gradient directions and local conductivity tensors.

The results emphasize the importance of small-scale structured sedimentary heterogeneity. Complex two- and three-dimensional structures with moderate conductivity ratios cause appreciable differences in upscaled conductivity tensors, which are enhanced when the local conductivities are slightly anisotropic. However, depending on the local conductivity tensors, the potentiometric heads and the flowline pattern can be uniform and the upscaled hydraulic conductivity can be isotropic, even though the model domain is heterogeneous. The amplitude and pattern of the head perturbation is controlled by the geometry, orientation, and magnitude of the local conductivity tensor, which defines the direction of the local fluid flow and ultimately controls the flowline, associated advective front morphology, and the "structure-induced dispersion." The potentiometric head and velocity pattern of locally slightly anisotropic models and high contrast locally isotropic are similar. The location and magnitude of the maximum velocity is dependent on the local conductivity tensor, the conductivity unit geometry, and the local head gradient. A "geometric hydraulic barrier" is generated where fast tensor components of adjacent nodes are at high angles.

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Two web-based interactive visualization tools were developed to support problem-based learning in tertiary introductory geoscience classes. The presented tools were designed using the Java™ programming language, following guidelines for good educational instruction design. They represent two different examples of how object-oriented programming can be used to enhance the quality of Internet-based instructional material. The Geomovie Java applet is an interactive animation template that allows students to visualize the geophysical seismic plane wave concept. Two-dimensional visualization of three-dimensional geological and geophysical concepts can improve the spatial ability of learners. The animated spatial path of the seismic plane wave is controlled by the learner-defined parameters. Student experimentation of the influence of the parameters on the characteristics of seismic waves results in active learning. This applet has been developed as a template, and can be used for development of other interactive, animated, two-dimensional concept demonstrations. The Geochart application has been developed as an interactive graphing tool for on-line investigation. The applet connects a database of geochemical variables for the South Platte River water quality collected during National Water Quality Program, and allows students to plot variables in XY coordinates, encouraging inquiry-based learning. Different plotting options are available. The system is developed using Java applet/servlet communication and allows future extension to other databases and systems.

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The Hickory Sandstone is an important aquifer in central Texas and is partitioned by faults that impede cross-fault fluid flow. This study provides a detailed stratigraphic and structural model in the vicinity of a normal, oblique-slip fault with 60’ (18.3 m) of stratigraphic throw. The model is developed using 3500’ (1050 m) of continuous core and geophysical logs from eleven closely spaced boreholes. The local stratigraphy is studied in detail and environments of deposition inferred. A model of fault evolution is inferred using the observed fault structure and throw distributions.

Locally, the Hickory Sandstone consists of 450’ (137 m) of Cambrian-aged, quartzose and arkosic sandstone with localized mudstone and siltstone interbeds and overlies Precambrian Town Mountain Granite. Within the study area, the Hickory Sandstone is subdivided into four facies: the cross-bedded facies, the mudstone facies, the interbedded sandstone facies and the hematite facies. These facies form a stacked sequence representing an initial braided-stream fluvial environment that grades into a high energy, open marine environment that closely matches the tide-dominated, high microtidal estuarine model of Reinson (1992). Lateral correlation of strata packages in the cross-bedded facies was very difficult and complicated development of the fault model.

The study fault is a linked fault system consisting of several major segments. Two segments overlap and locally hard link along both strike and dip. The major fault segments also consist of several linked subsegments. Net stratigraphic throw decreases slightly upward from a maximum of 60’ (18.3 m) near the granite basement. Where the major segments overlap, the throw exhibits systematic variations consistent with displacement transfer between the neighboring segments. The linked fault system is inferred to have formed by interaction and linkage of two, early, en echelon basement faults. Ultimately these faults propagated upward and laterally into the overlying Hickory Sandstone, interacted and partially hard-linked, producing a large linkage structure that affected subsequent, neighboring hanging wall deformation. Subsidiary small faults are common but do not exhibit simple spatial relations with the large fault segments. There is only a weak correlation between a fault’s shear zone thickness and stratigraphic throw for faults with 1’ to 60’ (0.3 to 18.3 m) of throw.

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Dinoflagellate biostratigraphy of the Upper Campanian-Danian was studied in five surface sections from Colombia and one from western Venezuela (Rio Loro section). The Rio Molino section is in northern Colombia, the Chiguata Creek and Tausa sections are in the central part of the Eastern Cordillera, La Buitrera Creek section is in the western flank of the Eastern Cordillera, and the Aico Creek Section is in the Upper Magdalena Valley. At least twenty-two biostratigraphically significant events where identified in the upper Campanian and Maastrichtian of the studied sections. In absence of calcareous macro- and microfossils the Campanian/Maastrichtian boundary was identified based on the highest occurrence of Trichodinium castanea and near the lowest occurrence of Phelodinium tricuspe, Yolkinigymnium lanceolatum and Hafniasphaera fluens. Several third-order coarsening upward cycles were recognized within the overall shallowing upward pattern displayed in the six sections. Dinoflagellates tend to be more abundant at the base of these cycles and peridinoid cysts dominate the dinoflagellate assemblage in most samples. During the upper Campanian carbonate sediments accumulated in northern Colombia (Socuy Limestones), while high paleo-productivity conditions generated biosiliceous sediments and condensed phosphorites in the Eastern Cordillera and the Upper Magdalena Valley (Plaeners Formation and Lidita Superior). These become younger to the east. Continuous, cyclic progradation from the east and south during the upper Campanian accumulated coarse-grained siliciclastics in proximal settings where sandstones are interbedded with porcelanites and cherts (Chiguata and Tausa sections). In more distal environments, micritic limestones and dark mudstones from the Buscavida Formation represent coeval sediments (La Buitrera Creek and Aico Creek sections). An expanded section of mudstones and sandstones from Los Pinos and Tierna Formations was recognized in the Chiguata Creek section relative to the Aico, La Buitrera, Rio Molino and Tausa sections. The K/T boundary is present in the Venezuelan section but coincides with an 11.5 m unexposed interval separating uppermost Maastrichtian dinoflagellate events below from Danian dinoflagellates above.

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