In 1983, President Ronald Reagan established the Exclusive Economic Zone, an area of 3.9 billion acres (∼1.6 billion hectares) that gives the United States exclusive rights to energy and mineral resources on and under the seafloor for a distance of 200 nautical miles (∼370 km) from its coastline and in its territorial seas [ Rowland et al. , 1983]. The U.S. Geological Survey established a program, EEZ‐Scan, in spring 1984 to map this new undersea territory [ Gardner , 1984; EEZ‐Scan Group, 1985]. The results of the first field season of mapping the EEZ off the conterminous west coast of the United States have been published as an atlas [ EEZ‐Scan 84 Scientific Staff , 1986] that is the first volume of a series.
In 1983, President Ronald Reagan signed a Proclamation establishing the Exclusive Economic Zone (EEZ) of the United States extending its territory 200 nautical miles from the coasts of the United States, Puerto Rico, the Northern Mariana Islands, and other U.S. territories and possessions. The charter of the U.S. Geological Survey (USGS) places the primary responsibility for mapping the territories of the United States within the USGS. Upon declaration of the EEZ, the territory of the United States was enlarged by more than 13 million square kilometers, all of which are under water. The USGS EEZ-SCAN program to systematically map the EEZ began in 1984 and continued through 1991. This digital publication contains all the GLORIA sidescan imagery of the deep-water (greater than 200 meters) portion of the EEZ mapped during those 8 years of data collection. For each EEZ area, we describe the data collection surveys and provide downloads of the GLORIA data and metadata.
Research Article| January 01, 1986 Terrane accretion, production, and continental growth: A perspective based on the origin and tectonic fate of the Aleutian–Bering Sea region David W. Scholl; David W. Scholl 1U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar Tracy L. Vallier; Tracy L. Vallier 1U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar Andrew J. Stevenson Andrew J. Stevenson 1U.S. Geological Survey, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar Geology (1986) 14 (1): 43–47. https://doi.org/10.1130/0091-7613(1986)14<43:TAPACG>2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation David W. Scholl, Tracy L. Vallier, Andrew J. Stevenson; Terrane accretion, production, and continental growth: A perspective based on the origin and tectonic fate of the Aleutian–Bering Sea region. Geology 1986;; 14 (1): 43–47. doi: https://doi.org/10.1130/0091-7613(1986)14<43:TAPACG>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Orogenesis in the Aleutian–Bering Sea region would create an expansive new area of Pacific-rim mountain belts. The region itself formed about 55 Ma as a consequence of the suturing of a single exotic fragment of oceanic crust—Aleutia—to the Pacific's Alaskan-Siberian margin. A massive overlap assemblage of the igneous crust of the Aleutian Arc and the thick sedimentary masses of the Aleutian Basin have since accumulated above the captured basement terrane of Aleutia.Future closure of the Aleutian–Bering Sea region, either northward toward the continent or southward toward the Aleutian Arc, would structurally mold new continental crust to the North American plate. The resulting "Beringian orogen" would be constructed of a collage of suspect terranes. Although some terranes would include exotic crustal rocks formed as far as 5000 km away, most terranes would be kindred or cotetonic blocks composed of the overlap assemblage and of relatively local (100–1000 km) derivation.The Aleutian–Bering Sea perspective bolsters the common supposition that, although disrupted and smeared by transcurrent faulting, examples of kindred assemblages should exist, and perhaps commonly, in ocean-rim mountain belts. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Research Article| February 01, 1983 Tectonic and geologic implications of the Zodiac fan, Aleutian Abyssal Plain, northeast Pacific ANDREW J. STEVENSON; ANDREW J. STEVENSON 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar DAVID W. SCHOLL; DAVID W. SCHOLL 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar TRACY L. VALLIER TRACY L. VALLIER 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar Author and Article Information ANDREW J. STEVENSON 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 DAVID W. SCHOLL 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 TRACY L. VALLIER 1U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1983) 94 (2): 259–273. https://doi.org/10.1130/0016-7606(1983)94<259:TAGIOT>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation ANDREW J. STEVENSON, DAVID W. SCHOLL, TRACY L. VALLIER; Tectonic and geologic implications of the Zodiac fan, Aleutian Abyssal Plain, northeast Pacific. GSA Bulletin 1983;; 94 (2): 259–273. doi: https://doi.org/10.1130/0016-7606(1983)94<259:TAGIOT>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Zodiac fan, a large body of upper Eocene through at least lower Oligocene turbidities, underlies the Aleutian Abyssal Plain and lies just south of the Aleutian Trench and the Alaskan Peninsula in the northeastern north Pacific. The fan deposits cover an area of more than 1 × 106 km2 and contain at least 280,000 km3 of terrigenous sediment. The most striking feature of the fan is its well-developed channel distributary system, which persists nearly to the plain limits. Levee overbank deposits associated with the channels are the dominant sedimentary style, a process believed to predominate on fans receiving primarily fine-grained detritus. Four major channels have been identified on the fan with the following relative age relation (> = older than): Sagittarius > Aquarius > Taurus, and Sagittarius >Seamap. Recently obtained seismic information implies that Seamap Channel may be older than Aquarius Channel. If Seamap is the youngest channel, a depositional interval of 8 m.y. (40−32 m.y. B.P.) is indicated for the fan as a whole. If Taurus is the youngest, as we believe, the interval of deposition is greater than 8 m.y. but is probably less than 16 m.y. (40−24 m.y. B.P.). Nanno-flora, pollen, and spores obtained from Deep Sea Drilling Site 183, near the northern margin of the fan, indicate that the fan formed in a nontropical (northern) environment, and that the source terrane had a climate similar to or slightly cooler than that recorded from coeval onshore deposits in the eastern Gulf of Alaska. On the basis of the interval of deposition, the volume of the fan, and sediment yield from climatically similar modern drainages, a minimum drainage of 500,000 km2 is believed necessary to have supplied the sediment to form the fan, assuming no sediment was deposited before it reached the fan. Tertiary plate-motion models requiring large amounts of relative convergence along the Aleutian Trench are judged unworkable, as such reconstructions require the Zodiac fan to have formed 1,500 to 3,000 km from the nearest continental landmass and separated from it by topographic barriers, requiring that the drainage be inflated in size manyfold to overcome anticipated sediment losses during such a lengthy transport. As the minimum drainage (500,000 km2) is already equal to one-half of the State of Alaska, any major expansion is judged unreasonable. This requires that relative convergence at the Aleutian Trench be limited to less than ∼500 km from 40 m.y. B.P. to present. A possible method by which this limitation can be satisfied is to allow a significant portion of southern Alaska to move in concert with the Pacific plate since the upper Eocene. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
