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Book
x, 62 leaves, bound.
Earth Sciences Library (Branner), Special Collections
Book
59 pages
Earth Sciences Library (Branner), Special Collections
Book
xi, 214 p.
Earth Sciences Library (Branner), Special Collections
Book
1 online resource.
This thesis focuses on the form and formation of Branched Channel Networks (BCNs). These networks are among the most striking forms that define the surface of our planet, and are the primary means that transport rock and water from high to low elevations across Earth's surface. As such, they play a fundamental role in shaping the elevation structure of continents, the spatial distribution of vegetation, and the rates and routes by which rocks, nutrients, and water are transported across different terrestrial reservoirs. BCNs also exist in extraterrestrial environments, where, as on Earth, they may encapsulate information regarding the processes and physical conditions under which these environments are shaped. In studying these networks, I pose two main hypotheses: (a) the structure of BCNs is sensitive to the erosional mechanics of the processes that carve them, and (b) a common set of constraints rationalizes the ubiquity of BCNs across disparate physical conditions (e.g., subaerial, submarine, extraterrestrial). First, I evaluate the limitations of the numerical tools with which I test these hypotheses, and show that the flow-routing rules used for the downslope routing of water and sediment over gridded Digital Elevation Models (DEMs) have a statistically significant impact on the form of modeled topography and the spatial distribution of modeled geomorphic processes. Having these limitations in mind, I address the first hypothesis, and show that the structure of BCNs reflects two coupled constraints: (1) the characteristic along-flow channel profile shaped by the channel forming processes, and (2) the fact that two flows initiating at an infinitesimal distance apart on each side of a drainage divide must experience an identical elevation drop between the divide and the junction where these flows once again meet. I then use numerical Landscape Development Model (LDMs) and analysis tools to demonstrate that these constraints impact the plan-view structure of BCNs as well as their temporal evolution, and that the form of these networks is indeed sensitive to the erosional mechanics of the processes that shape them. To address the second hypotheses, I analytically show that a simple dependence between sediment transport rate and the frequency at which geophysical flows traverse landscapes rationalizes the formation of BCNs by a wide variety of process, regardless of the stochasticity or homogeneity in which these processes are generated in time and/or space. Thus, as long as this dependency exists, networks may form by a variety of processes across disparate physical conditions. I then use LDMs based on this analytical framework to demonstrate the conditions for network formation and the relationships between the physical characteristics of flows and the landscape features they form.
Earth Sciences Library (Branner), Special Collections
Book
xii, 101 leaves, bound.
Earth Sciences Library (Branner), Special Collections
Book
vii, 227 p.
Earth Sciences Library (Branner), Special Collections
Book
ix, 52 leaves.
Earth Sciences Library (Branner), Special Collections
Book
xi, 188 leaves.
Earth Sciences Library (Branner), Special Collections
Book
xxxv, 326 p. : ill., maps ; 32 cm
  • List of illustrations
  • Publisher's foreword / Michael A. Keller
  • Exploring the Eighteenth Century: The Charles J. Tanenbaum Collection at the Stanford University Libraries / Benjamin Stone
  • Charles Tanenbaum, book collector / John E. Mustain
  • Charles J. Tanenbaum, librarian / Michael Ryan
  • The Charles J. Tanenbaum Collection and the crisis of independence / Jack Rakove
  • Kings and republicans in the collection of Charles J. Tanenbaum / Caroline Winterer
  • Editorial preface / Benjamin Stone
  • The Tanenbaum Collection at the Stanford University Libraries
  • The Tanenbaum Collection at the Stanford University Libraries, manuscripts
  • Index.
Art & Architecture Library (Bowes), Earth Sciences Library (Branner), Special Collections
Book
xxii, 227 pages.
Earth Sciences Library (Branner), Special Collections
Book
xiii, 100 leaves bound.
Earth Sciences Library (Branner), Special Collections

12. Memoirs [2012]

Book
1 v. (various pagings) : ill. (some col.) ; 28 cm.
Finding aid
Online Archive of California
Earth Sciences Library (Branner), Special Collections
Book
xi, 109 leaves, bound.
Earth Sciences Library (Branner), Special Collections
Book
1 online resource.
This dissertation aims to improve the interpretation of thinly bedded sand-shale systems that are below resolution of conventional well-log and seismic data by using rock physics and quantitative seismic analysis. The key contributions of this dissertation are (1) incorporation of parameter uncertainties into existing models that are used for estimating petrophysical properties of sub-resolution sand-shale systems, (2) a new method for approximating fluid substitution in thinly bedded sand-shale reservoirs that is applicable at the measurement scale without the need to downscale the measurements, and (3) an application of rock physics, spatial statistics, and feature-extraction based attributes to quantitatively interpret seismic data for sub-resolution reservoir properties such as net-to-gross ratio, saturation, and stacking pattern. Most of rock physics relations are derived for rocks that are considered homogeneous at particular scales. If these relations are applied to measurements at other scales, the relations often fail when the measurements represent average properties of heterogeneous rocks (for example, a stack of interbedded sand and shale layers). First, we investigate the Thomas-Stieber model, a model commonly used for estimating volume fraction of sand and its porosity in thinly bedded sand-shale sequences. We present sensitivity and uncertainty analyses of this model under various scenarios, especially when the model assumptions are violated. We also extend the model by incorporating uncertainties into the model parameters using Monte Carlo simulations in a Bayesian framework. Next, we propose a simple graphical mesh interpretation and accompanying equations for approximating fluid substitution in sub-resolution interbedded sand-shale sequences. The advantages of our method are as follows. Even when it is applied to the measurements at their original scales, our method appropriately changes fluid in the sands only, without the need to downscale the measurements. The interbedded sand layers can be either clean or shaly (i.e., sand with dispersed clay). We illustrate the performance of the model using both synthetic and real well log data and present sensitivity analysis of the model parameters. Estimating reservoir properties of sub-resolution sand-shale reservoirs from seismic data is not straightforward because the relation between seismic signatures and rock properties are not unique. This relation is even further complicated by the spatial arrangement of the sub-resolution layers. This dissertation presents a workflow for seismic interpretation of such thin reservoirs. The workflow consists of four main steps: (1) estimate transition matrices (Markov chain model) at the well location from log data, (2) use the matrices to create various sand-shale sequences with varying reservoir properties such as net-to-gross ratio, saturation, and stacking pattern, (3) generate synthetic seismograms corresponding to the sequences and from these seismograms extract attributes which will be used as a training set, and (4) finally use the training set to estimate reservoir properties of the area away from the well. Most of seismic attributes discussed here are obtained using feature-extraction techniques, which compare amplitudes of seismogram segments and find new representations of these seismograms in a new, smaller set of features. We apply the workflow to both synthetic data and real data from channelized turbidite deposits in West Africa.
Earth Sciences Library (Branner), Special Collections
Book
x, 61 leaves, bound.
Earth Sciences Library (Branner), Special Collections
Book
vii, 34 leaves, bound.
Earth Sciences Library (Branner), Special Collections
Book
xx, 195 p.
Collection
PhD Dissertations, Stanford Earth
Earth Sciences Library (Branner), Special Collections
Book
xviii, 168 p. bound.
Earth Sciences Library (Branner), Special Collections
Book
xxv, 248 p.
Collection
PhD Dissertations, Stanford Earth
Earth Sciences Library (Branner), Special Collections
Book
xx, 197 leaves, bound.
Collection
PhD Dissertations, Stanford Earth
Earth Sciences Library (Branner), SAL3 (off-campus storage), Special Collections