ALOHA BREEZE FLOOR FAN

Handbook of Seafloor Sonar Imagery (Wiley-Praxis Series in Remote Sensing)

Images of the Earth’s seafloor acquired by acoustic (sonar) systems are usually difficult to interpret because of their nature and because of the complex and varied geological processes at play. In recent years, there have been huge advances in acoustic remote sensing and its applications. This unique and timely handbook provides end-users, as well as specialists, with a single source of reference covering all stages from data acquisition to interpretation and decision-making. Drawing on their first hand experience of state-of-the-art sonar systems, the authors review the different types of sonar available and the various stages of data processing. They then focus on the distinct types of geological environments present in the deep ocean in the vicinity of mid-ocean ridges and geological plate boundaries — volcanic structures, tectonic structures and sedimentary processes — each illustrated with representative sea floor images, detailed reasoning and interpretations. Each chapter is followed by a short bibliography covering the main references, and an extended bibliography appears at the end of the book. The book also discusses sonar imagery interpretation, particularly the recognition of image anomalies and their correction. The many real-life examples of errors and anomalies, and how they can be detected and corrected, draw upon the authors’ wealth of experience of at-sea acquisition of sonar data, its processing and interpretation. The combination of theory and practical experience, extensive use of real sonar images, and explanations of the reasoning behind the final interpretation, all contribute to make this book a comprehensive reference work for users of acoustic imagery, ranging from the novice to experienced marine geologists. Readership: Professional scientists involved with the acquisition, processing, analysis and interpretation of marine sonar images, for applications in marine geology and deep sea studies. Scientists, engineers and surveyors in industry involved in hazard assessment for cable surveys, the placement of oil platforms, pipelines and wellheads. The book will also serve as a useful reference work for university undergraduate and postgraduate students studying in remote sensing, marine science, oceanography, geology, geophysics, environmental science and related subject areas.

During a stint as a draftsman/photographer at a San Francisco engineering firm specializing in the design of semisubmersible offshore drilling platforms, I took this photograph of a seafloor blowout preventer. Although this was taken in 1977, the recent devastation in the Gulf of Mexico--Petrochernobyl--suggests that little has been accomplished in the way of improvements over this antique model. If one can get beyond the recent bad press surrounding this type of apparatus, I believe it possesses considerable sculptural beauty...

Photographed in 1977 with a Canon SLR; 35 mm Kodachrome; exposure data unavailable

Mud seafloors off Oregon are commonly being disrupted by trawling, according to a new report by scientists from Oregon State University. Particularly affected are species such as two-foot-long sea pens, observed on the sea floor 600 feet deep off California. (Photo courtesy of Northwest Fisheries Science Center, NOAA Fisheries Service)