Currents in Monterey Submarine Canyon


Book Description

Time series were obtained from two current meters near bottom on one mooring in Monterey Submarine Canyon. These records were analyzed to determine the general character of the currents, the volume transport at different levels above the canyon floor, the power spectral estimates of the upcanyon and cross-caynon directional components, and the coherence between directional components. Current speed variations appeared as a series of peaks occurring every 5 to 6 hr with maxima of 17 to 21 cm/sec. Current directions oscillated with a discernible period of about 12 hr. Currents 30 m above the bottom were aligned nearly along the canyon axis; currents 60 m above the bottom were nearly perpendicular to the canyon axis. The spectral analysis indicated tides as a major driving force of the deep currents, but also indicated the presence of other forcing functions, possibly internal waves, with shorter periods. The coherence between instruments was low, suggesting the possible presence of a near-bottom boundary layer, or that significant signal deterioration was caused by noise.




Mass Transport, Gravity Flows, and Bottom Currents


Book Description

Mass Transport, Gravity Flows, and Bottom Currents: Downslope and Alongslope Processes and Deposits focuses solely on important downslope and alongslope processes. The book provides clear definitions and characteristics based on soil mechanics, fluid mechanics and sediment concentration by volume. It addresses Slides, Slumps, and Debris Flows, Grain Flows, Liquefied/Fluidized Flows, and Turbidity Currents, Density plumes, Hyperpycnal Flows, the Triggering Mechanisms of Downslope Processes, Bottom Currents, and Soft-Sediment Deformation Structures. The mechanics of each process are described in detail and used to provide empirically-driven categories to help recognize these deposits it the rock record. Case studies clearly illustrate of the problems inherent in recognizing these processes in the rock record, and potential solutions are provided alongside future avenues of research. An appendix also provides step-by-step guidance in describing and interpreting sediments. - Comprehensively addresses modern downslope and alongslope processes, including definitions and mechanisms - Provides key criteria for the recognition of depositional facies in the rock record - Includes case studies to illustrate each downslope and alongslope process - Identifies key problems and potential solutions for future research - Uses pragmatic, empirical, data-driven interpretations to revise conventional facies models




Deep-Water Processes and Facies Models: Implications for Sandstone Petroleum Reservoirs


Book Description

This rock-based book is an attempt to link deep-water process sedimentology with sandstone petroleum reservoirs. In presenting a consistent process interpretation, the author has relied on his description and interpretation of core and outcrop (1:20 to 1:50 scale) from 35 case studies (which include 32 petroleum reservoirs), totaling more than 30,000 feet (9,145 m), carried out during the past 30 years (1974-2004). This book should serve as an important source of information for students on history, methodology, first principles, advanced concepts, controversies, and practical applications on deep-water sedimentology and petroleum geology.* Discusses the link between deep-water process sedimentology and petroleum geology * Addresses criteria for recognizing deposits of gravity-driven, thermohaline-driven, wind-driven, and tide-driven processes in deep-water environments* Provides head-on approach to resolve controversial process-related problems




Deep Marine Systems


Book Description

Deep-water (below wave base) processes, although generally hidden from view, shape the sedimentary record of more than 65% of the Earth’s surface, including large parts of ancient mountain belts. This book aims to inform advanced-level undergraduate and postgraduate students, and professional Earth scientists with interests in physical oceanography and hydrocarbon exploration and production, about many of the important physical aspects of deep-water (mainly deep-marine) systems. The authors consider transport and deposition in the deep sea, trace-fossil assemblages, and facies stacking patterns as an archive of the underlying controls on deposit architecture (e.g., seismicity, climate change, autocyclicity). Topics include modern and ancient deep-water sedimentary environments, tectonic settings, and how basinal and extra-basinal processes generate the typical characteristics of basin slopes, submarine canyons, contourite mounds and drifts, submarine fans, basin floors and abyssal plains.




Observations and Modeling of the Internal Tide in a Submarine Canyon


Book Description

Shipboard ADCP and CTD measurements were conducted in Monterey Submarine Canyon in April and October 1994 to determine the propagation characteristics and energy levels of the semidiurnal internal tide. The measurements reveal a bottom intensified internal tide propagating energy up canyon. The region of strongest motion is in a beam 150-200 m thick, centered approximately 150 m above the Canyon floor. Along canyon baroclinic M2 currents are typically 15-20 cm/s, an order of magnitude larger than the estimated barotropic tidal currents. In April 1994, the internal tidal beam is well described by a progressive wave, while in October 1994, the signal is standing along and perpendicular to the beam. The Princeton Ocean Model was used to study the generation and propagation of semidiurnal internal tides in submarine canyons and to investigate their sensitivity to canyon shape.




Atlas of Deep-Water Outcrops


Book Description

Hardcover plus CD







Characterization of Tidal Currents in Monterey Bay from Remote and In-situ Measurements


Book Description

A first order description of tidal heights and currents in Monterey Bay is provided. Analysis of sea level records indicate that a mixed, predominantly semidiurnal tide nearly co-oscillates within the bay. Analysis of month-long moored ADCP records obtained in the winter and summer of 1992 reveals that tidal-band currents account for approximately 50 percent of the total current variance in the upper ocean (20-200 m). A relatively strong (7 cm/s) fortnightly tide (MSf) is present in both seasons. Considerable rotation of the semidiurnal ellipse orientations occurs with depth during both seasons. A month- long record of surface current measurements obtained with CODAR, an HF radar system, during September 1992 reveals that the Monterey Submarine Canyon clearly influences the strength and direction of semidiurnal (M2) tidal currents. Good agreement exists between the strength and orientation of ADCP- and CODAR-derived tidal ellipses, with the exception of the constituent K1. Large, spatially uniform K1 surface currents (20-30 cm/s) appear to be the result of diurnal sea breeze forcing.




Economic and Palaeoceanographic Significance of Contourite Deposits


Book Description

There has lately been a growth in the number and level of studies of contourite deposits. Most recent studies of contourites have two major lines of interest. One, propelled by the oil industry's continuous move into increasingly deep waters, concerns their economic significance. The other involves the stratigraphic/ palaeoceanographic record of ocean circulation changes imprinted on contourite deposits that can be a key to understanding better the climate-ocean connection. The application of many different theoretical, experimental and empirical resources provided by geophysics, sedimentology, geochemistry, petrology, scale modeling and field geology are used in the 16 papers of this volume, proposing answers to those two main aspects. The papers are subdivided into two major categories (economic interest and stratigraphic/palaeoceanographic significance), with case studies ranging from well-documented drifts to new examples of modern and fossil series, involving a large diversity of geographic and physiographic scenarios worldwide