SWLGS Luncheon Topics
Updated Jan. 4, 2007
Advances in Deepwater AUV Remote Sensing Technology and Selected Geologic Feature Examples
By Tony George, C&C Technologies
Six years have passed since AUVs first entered the market place as a commercially viable geohazard survey option for seabed investigations in water depths up to 3,000 m. Oil and gas developments located on the continental slopes are dependent on high-resolution multibeam, side scan sonar and subbottom profiler data acquired by AUVs for engineering the proposed infrastructure. The first generation AUVs are nearing the end of their life cycle. A new system (C-Surveyor III) and upgrades to the current systems are planned for the first quarter of 2007. One of the improvements AUVs includes increasing the water depth-rating limit from 3,000 to 4,500 m. The new and upgraded AUVs will have a longer hydrodynamic shell allowing more space to accommodate a larger battery and geophysical instrumentation. Improved subbottom profiler and side scan sonar instrumentation are incorporated as part of the upgrades. This first half of this presentation will briefly describe the sensor upgrades and improvements to the side scan sonar and subbottom profiler compared to the current systems.
Company AUVs have collected more than 75,000 kilometers of high-resolution geophysical data in the Gulf of Mexico, Florida Straits, Mediterranean Sea, West Africa and Brazil. These seabed investigations have uncovered numerous interesting seabed and shallow geologic features. Intensely faulted zones, fluid expulsion zones, large seabed pockmarks, mud volcanoes, deepwater corals, hydrate mounds, mass sediment transport units and large seabed furrows are a few of the features encountered on these geohazard surveys. The use of 3D visualization software is paramount to the interpretation and understanding of these features. 3D visualization provides the interpreter with details on subtle features that may otherwise go unnoticed. 3D visualization techniques allow engineers to view how features or seabed topography may impact their proposed infrastructure. Data examples of interesting features encountered on AUV surveys using 3D visualization are included in this presentation. The presentation briefly outlines the methods, processing techniques and results of a 3D microseismic AUV survey performed of a newly forming, 600-m diameter pockmark found on the upper continental slope of Nigeria.
Robert A. “Tony” George is employed with C & C Technologies, Inc. (C&C) as the Geosciences Manager for both Houston and Lafayette offices. He currently supervises a team of 35 geoscientists, marine archaeologists and cartographers who specialize in the processing, interpretation and mapping of high-resolution geophysical data for hydrographic, geohazard and archaeological surveys. Tony has participated in numerous geohazard surveys for shallow and deepwater oil and gas developments in the Gulf of Mexico, West Africa, Brazil and the Mediterranean. He has managed telecommunication survey projects in North and South America and in Southeast Asia.
Tony entered the oil field in 1985 as a junior observer for Inland Geophysical Company, a small 2D exploration seismic company operating in Texas and Louisiana. He joined John E. Chance and Associates in 1988 and spent 2 years in the field as an observer and operator before moving to an office position as geophysicist. Tony joined C&C in 1995 as a senior geophysicist and moved to a management position 2 years later.
In 1999, C&C took an initiative to develop a deepwater AUV for commercial use by the oil and gas industry. Tony worked with the system development engineers in designing the workflows and data formats used for the storage, processing and interpretation of the data acquired with this first generation AUV.