ALBERT

Description / Table of Contents: PREFACE The ocean has always been reluctant to reveal its secrets. Its size and the inaccessibility of its deeper regions have made their safeguard a reasonably simple matter with the result that significant misconceptions persisted for many years. Two of the most widespread of these concerned the featureless nature of the sea floor and the silence of the deep ocean. Underwater acoustics has played a key role in discrediting both and in so doing introduced new and exciting developments in oceanography and geophysics. In the years following World War II, echosounders and subbottom profilers based on new active sonar technology, revealed the true nature of the seafloor topography and led to the major advances represented by plate tectonics. Research driven by the requirements of passive sonar, on the other hand, was to demonstrate that the sea was not silent but was characterised by a complex noise spectrum. Many individual mechanisms and sources ranging from man-made, biological and geophysical activity to the intrinsic noise of the sea itself were found to contribute to this spectrum. A major component, which is the subject of this book, was to remain unrecognised to underwater acoustics until noise measurements could be made effectively at very low frequencies, although its presence had been indicated by seismology long before these measurements were possible. By virtue of its geographical isolation in the Southern Ocean, New Zealand has provided an ideal environment for long-range propagation and ambient noise investigations and numerous studies have been reported. Our interest in the subject of this book was aroused initially in the course of one such experiment in 1966. For the first time it had been possible to extend the recording bandwidth to 1 Hz and the improved performance of this new system was anticipated eagerly. However the main purpose of the experiment was nearly aborted by the appearance of a new and unsuspected noise component at frequencies below 10 Hz. Due primarily to technical limitations in the equipment then available, a subsequent programme, designed to identify the properties and origin of the source more clearly, was not productive and was soon abandoned. An opportunity to revisit the problem arose some 10 years later, when the University of Auckland became involved in a major environmental study in support of the development of an offshore gas field in Cook Strait. The technology then available provided an opportunity to examine afresh the relationship between sea state and the seismo-acoustic response generated. An initial trim demonstrated the potential of the site. Accordingly a long-term programme, involving the parallel measurement of the oceanwave field and acoustic response, was undertaken in a series of student research theses. The data so gathered were of sufficiently high quality to ultimately establish wave-wave interactions as the source of the acoustic effects observed and to identify many of its characteristics. This result was soon to be confirmed by other studies. As the noise data accumulated, however, it became apparent that certain refinements to the theories describing the mechanism were required. Our attempts to provide these refinements have been reported in a number of contributions in recent years. The accounts of these and similar contributions by others have unfortunately appeared in the literature in a somewhat disjointed manner, with the result that the evolution of the subject has not been easy to follow. This book attempts to present a more coherent account of the subject and its development. Most of the early experimental and theoretical results from our group have arisen from two key Ph.D. theses, due to Dr. K.C. Ewans and Dr. C.Y. Wu. The painstaking and careful instrumentation development and data analysis provided by Dr. Ewans were critical to the definitive correlation which we were able to establish between wind field, seastate and the acoustic response so generated. Dr. Wu's thesis presented the first phase of our attempt at the resolution of certain key theoretical issues, which were identified in the course of the experimental programme. Both studies owe much to the support of Shell BP Todd Oil Services Ltd., acting for Maui Development Ltd., and to the University of Auckland. The support of the Electricity Corporation of New Zealand Ltd. during a later experimental investigation of the Southern Ocean wave field is also acknowledged...

Description / Table of Contents: Plate tectonics has significantly broadened our view of the dynamics of continental evolution, involving both the processes currently active at the surface and those extending deep into the interior of the Earth. Seismic anisotropy provides some of the most diagnostic evidence for mapping past and present deformation of the entire crustmantle system. This volume contains papers presented originally at an international workshop at the Chateau of Trest in the Czech Republic in 1996. This workshop brought together geophysicists and geologists who work in the field of observational and theoretical seismology, mineral and rock physics, gravity studies and geodynamic modelling. Topics include large-scale anisotropy of the Earth's mantle, mantle heterogeneity vs. anisotropy 3-D velocity and density structures and inferences on mantle dynamics, mineral and rock physics studies, and mathematical aspects of complex wave propagation.

Description / Table of Contents: The special issue contains contributions presented at the international workshop Seismic waves in laterally inhomo- geneous media IV, which was held at the Castle of Trest, Czech Republic, May 22-27, 1995. The workshop, which was attended by about 100 seismologists from more than 10 countries, was devoted mainly to the current state of theoretical and computational means of study of seismic wave propagation in complex structures. The special issue can be of interest for theoretical, global and explorational seismologists. The first part contains papers dealing with the study and the use of various methods of solving forward and inverse problems in complicated structures. Among other methods, discrete-wave number method, the finite-difference method, the edge-wave supperposition method and the ray method are studied and used. Most papers contained in the second part are related to the ray method. The most important topics are two-point ray tracing, grid calculations of travel times and amplitudes and seismic wave propagation in anisotropic media.

Description / Table of Contents: This volume contains 18 papers from 8 countries dealing with different aspects of triggered and induced seismicity. In situ observations of the phenomenon include examples of seismicity due to reservoirs, hard-rock mines, coal mines, mine collapses, brine production caverns, fluid injections, and geothermal hot-dry-rock projects. High-frequency acoustic emission studies from laboratory experiments and hard-rock mines have also been reported. Besides providing case studies of previously unavailable observations of seismicity, the present volume contains investigations of the causes and source mechanism of seismic events, determination of source parameters, seismic hazard as related to the design of support systems for underground openings and procedures for closure of brine production caverns, and the use of seismic and non-destructive techniques in assessing rock damage, measuring dynamic elastic moduli and detecting discontinuities. This collection of papers provides an excellent indication of the state of the art, recent developments and outstanding challenges facing scientists and engineers in understanding the causes and alleviating the effects of induced seismicity.

Description / Table of Contents: The perturbation of the earth by mankind causes earthquakes in a variety of situations. This phenomenon continues to be a major concern to engineers and scientists concerned with the mitigation of the consequences of this seismicity, as well as better understanding the processes at its origin. The present volume contains twelve papers from six countries, dealing with observations of triggered and induced seismicity in four continents. The reported cases include seismicity due to hard-rock mines, coal mines, underground research facilities for nuclear waste disposal, water injections, reservoirs, acquifers and oil fields. This volume provides case studies of previously unavailable observations of this phenomenon, investigations of the cause and source mechanism of seismic events, studies of source location distributions, determinations of seismic source parameters, cases of the use of such parameters in assessing rockburst hazard in mines, and measurements of velocity an attenuation properties of rock masses. The present collection of papers provides an excellent indication of the current state of the art and new developments in this area of research.

Description / Table of Contents: Earthquakes in shallow subduction zones account for the greatest part of seismic energy release in the Earth and often cause significant damage; in some cases they are accompanied by devastating tsunamis. Understanding the physics of seismogenic and tsunamigenic processes in such zones continues to be a challenging focus of ongoing research. The seismologic and geodetic work reported in this volume highlights the recent advances made toward quantifying and understandig the role of shallow plate coupling in the earthquake generation process. The relation between regional seismotectonics, features in the downgoing plate, and the slip distribution in earthquakes are examined for recent and great historical events. In addition to papers reporting new results, review articles on tsunami and tsunamigenic earthquakes and depth dependent plate interface properties are presented. These observational results, along with complementary laboratory and theoretical studies, can assist in assessing the seismic potential of a given region.

Description / Table of Contents: Geodynamics concerns with the dynamics of the global motion of the earth, of the motion in the earth's interior and its interaction with surface features, together with the mechanical processes in the deformation and rupture of geological structures. Its final object is to determine the driving mechanism of these motions which is highly interdisciplinary. In preparing the basic geological, geophysical data required for a comprehensive mechanical analysis, there are also many mechanical problems involved, which means the problem is coupled in a complicated manner with geophysics, rock mechanics, seismology, structural geology etc. This topical issue is Part I of the Proceedings of an IUTAM / IASPEI Symposium on Mechanics Problems in Geodynamics held in Beijing, September 1994. It addresses different aspects of mechanics problems in geodynamics involving tectonic analyses, lithospheric structures, rheology and the fracture of earth media, mantle flow, either globally or regionally, and either by forward or inverse analyses or numerical simulation.

Description / Table of Contents: Geodynamics concerns the dynamics of the earth's global motion, of the earth's interior motion and its interaction with surface features, together with the mechanical processes in the deformation and rupture of geological structures. Its final object is to determine the driving mechanism of these motions. It is highly interdisciplinary. In providing the basic geological, geophysical infromation required for a comprehensive mechanical analysis, there are also many mechanical problems involved, which means the problem is coupled intricately with geophysics, rock mechanics, seismology, structural geology, etc. This is Part II of the Proceedings of an IUTAM/IASPEI Symposium on Mechanics Problems in Geodynamics held in Beijing, September 1994. It discusses different aspects of mechanics problems in geodynamics involving the earth's rotation, tectonic analyses of various parts of the world, mineral physics and flow in the mantle, seismic source studies and wave propagation and application of the DDA method in tectonic analysis.

Description / Table of Contents: PREFACE There can be little doubt that estuarine, coastal and shelf circulation modeling will assume increasing importance in the immediate future, as we work through the implications of industrialization for oceanic systems. These issues will place new and serious operational demands on available models, and the rapid increase in computational power we now enjoy makes it possible to respond with detailed simulations in many categories. As a result, we are witnessing an explosive growth in the quantity of model-generated information. Lacking, however, is a concomitant increase in its quality or even in quality control procedures. A single simulation exercise is easily capable of generating gigabytes of output in a matter of hours. Most of the data will necessarily go unexamined by its progenitors. Yet it is highly likely that disks full of simulation output will be used extensively as learning tools for students and researchers, as criteria for engineering design, as a basis for operational decision-making, and in the formulation of public policy. The purpose of this volume is to assemble and present what is known about the intrinsic quality of simulation output: its "correctness" for various purposes. We have operated on the twin premises that (1) every simulation has some intrinsic value and (2) every simulation has serious drawbacks. Between these two extremes lies a vast gulf of uncertainty and potential error, which must be bridged in a professional way if modeling is to achieve its potential in the coastal ocean. This is the basic challenge put to the authors of this volume. Essentially we seek to describe and consolidate approaches, theories, and practices for extracting information from models, and to understand the limits of their proper use. We have focused on quantitative approaches to the problem, from diverse physical and mathematical perspectives. Rather than pursuing abstract, philosophical analyses, we have sought contributions reflecting contemporary practice in government, academic, engineering, and research units where frontier model development is taking place. In a similar spirit, we have avoided imposing linguistic norms among authors, which we view as unproductive at this time. Instead, we have let the authors describe their approaches to this multi-faceted problem in their own terms, subject only to standards of clarity of expression. We are especially pleased to have balanced representation from European and North American authors. This volume was initially conceived at an informal workshop in Brussels, convened by our great friend and colleague, the late Bruno M. Jamart. That event first brought several of the contributing authors together over the skill assessment theme, and seeded a mutual vision of the present work. Bruno's energy, insight, integrity, collegiality, and boundless spirit has been an inspiration to all who knew and worked with him. His untimely death in 1990 represents a great loss which is deeply and widely felt. In his memory we dedicate this volume, a humble memorial to a great spirit and friend.

Description / Table of Contents: V. P. Wright and T. P. Burchette: Carbonate ramps: an introduction / Geological Society, London, Special Publications, 149:1-5, doi:10.1144/GSL.SP.1999.149.01.01 --- W. M. Ahr: Carbonate ramps, 1973–1996: a historical review / Geological Society, London, Special Publications, 149:7-14, doi:10.1144/GSL.SP.1999.149.01.02 --- A. Kirkham: A Quaternary proximal foreland ramp and its continental fringe, Arabian Gulf, UAE / Geological Society, London, Special Publications, 149:15-41, doi:10.1144/GSL.SP.1999.149.01.03 --- Gordon Walkden and Alun Williams: Carbonate ramps and the Pleistocene-Recent depositional systems of the Arabian Gulf / Geological Society, London, Special Publications, 149:43-53, doi:10.1144/GSL.SP.1999.149.01.04 --- Viviane Testa and Dan W. J. Bosence: Carbonate-siliciclastic sedimentation on a high-energy, ocean-facing, tropical ramp, NE Brazil / Geological Society, London, Special Publications, 149:55-71, doi:10.1144/GSL.SP.1999.149.01.05 --- Janice M. Light and John B. Wilson: Cool-water carbonate deposition on the West Shetland Shelf: a modern distally steepened ramp / Geological Society, London, Special Publications, 149:73-105, doi:10.1144/GSL.SP.1999.149.01.06 --- J. Fred Read: Phanerozoic carbonate ramps from greenhouse, transitional and ice-house worlds: clues from field and modelling studies / Geological Society, London, Special Publications, 149:107-135, doi:10.1144/GSL.SP.1999.149.01.07 --- M. Aurell, B. Bádenas, D. W. J. Bosence, and D. A. Waltham: Carbonate production and offshore transport on a Late Jurassic carbonate ramp (Kimmeridgian, Iberian basin, NE Spain): evidence from outcrops and computer modelling / Geological Society, London, Special Publications, 149:137-161, doi:10.1144/GSL.SP.1999.149.01.08 --- Martyn Pedley: A review of sediment distributions and processes in Oligo-Miocene ramps of southern Italy and Malta (Mediterranean divide) / Geological Society, London, Special Publications, 149:163-179, doi:10.1144/GSL.SP.1999.149.01.09 --- Rodney F. Gilham and Charlie S. Bristow: Facies architecture and geometry of a prograding carbonate ramp during the early stages of foreland basin evolution: Lower Eocene sequences, Sierra del Cadí, SE Pyrenees, Spain / Geological Society, London, Special Publications, 149:181-203, doi:10.1144/GSL.SP.1999.149.01.10 --- H. D. Sinclair, Z. R. Sayer, and M. E. Tucker: Carbonate sedimentation during early foreland basin subsidence: the Eocene succession of the French Alps / Geological Society, London, Special Publications, 149:205-227, doi:10.1144/GSL.SP.1999.149.01.11 --- Irene Gómez-Pérez, Pedro A. Fernández-Mendiola, and Joaquín García-Mondéjar: Constructional dynamics for a Lower Cretaceous carbonate ramp (Gorbea Massif, north Iberia) / Geological Society, London, Special Publications, 149:229-252, doi:10.1144/GSL.SP.1999.149.01.12 --- Martina Bachmann and Jochen Kuss: The Middle Cretaceous carbonate ramp of the northern Sinai: sequence stratigraphy and facies distribution / Geological Society, London, Special Publications, 149:253-280, doi:10.1144/GSL.SP.1999.149.01.13 --- Ana C. Azerêdo: Geometry and facies dynamics of Middle Jurassic carbonate ramp sandbodies, West-Central Portugal / Geological Society, London, Special Publications, 149:281-314, doi:10.1144/GSL.SP.1999.149.01.14 --- Kinga Hips: Lower Triassic storm-dominated ramp sequence in northern Hungary: an example of evolution from homoclinal through distally steepened ramp to Middle Triassic flat-topped platform / Geological Society, London, Special Publications, 149:315-338, doi:10.1144/GSL.SP.1999.149.01.15 --- Ákos Török: Controls on development of Mid-Triassic ramps: examples from southern Hungary / Geological Society, London, Special Publications, 149:339-367, doi:10.1144/GSL.SP.1999.149.01.16 --- Zakaria Lasemi, Rodney D. Norby, and Janis D. Treworgy: Depositional facies and sequence stratigraphy of a Lower Carboniferous bryozoan-crinoidal carbonate ramp in the Illinois Basin, mid-continent USA / Geological Society, London, Special Publications, 149:369-395, doi:10.1144/GSL.SP.1999.149.01.17 --- Jobst Wendt and Bernd Kaufmann: Mud buildups on a Middle Devonian carbonate ramp (Algerian Sahara) / Geological Society, London, Special Publications, 149:397-415, doi:10.1144/GSL.SP.1999.149.01.18 --- Bernd Kaufmann: Middle Devonian reef and mud mounds on a carbonate ramp: Mader Basin (eastern Anti-Atlas, Morocco) / Geological Society, London, Special Publications, 149:417-435, doi:10.1144/GSL.SP.1999.149.01.19 --- Yong Seok Choi and J. A. Simo: Ramp facies and sequence stratigraphic models in an epeiric sea: the Upper Ordovician mixed carbonate-siliciclastic Glenwood and Platteville Formations, Wisconsin, USA / Geological Society, London, Special Publications, 149:437-456, doi:10.1144/GSL.SP.1999.149.01.20