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Research about Chukchi Sea

Source-linked reports with geographic coverage including Chukchi Sea.

25 records · Page 2Linked to original sources
USGS1986

Multichannel seismic-reflection data collected in 1980 in the eastern Chukchi Sea

The U.S. Geological Survey (USGS) collected approximately 2,652 km of 24-channel seismic-reflection data in early September, 1980, over the continental shelf in the eastern Chukchi Sea (Fig. 1). The profiles were collected on the USGS Research Vessel S.P. Lee. The seismic energy source consisted of a tuned array of five airguns with a total volume of 1213 cubic inches of air compressed to approximately 1900 psi. The recording system consisted of a 24-channel, 2400 meter long streamer with a group interval of 100 m, and a GUS (Global Universal Science) model 4200 digital recording instrument. Shots were fired every 50 meters. Navigational control for the survey was provided by a Magnavox integrated navigation system using transit satellites and doppler-sonar augmented by Loran C (Rho-Rho). A 2-millisecond sampling rate was used in the field; the data were later desampled to 4-milliseconds during the demultiplexing process. 8 seconds data length was recorded. Processing was done at the USGS Pacific Marine Geology Multichannel Processing Center in Menlo Park, California, in the sequence: editing-demultiplexing, velocity analysis, CDP stacking, deconvolution-filtering, and plotting on an electrostatic plotter. Plate 1 is a trackline chart showing shotpoint navigation.

Alaska↗
USGS1975

Petrography of University of Washington dredge samples for the central Chukchi Sea

Twenty thin sections of rocks dredged from the central Chukchi Sea have been examined petrographically and compared with some onshore rocks in northern Alaska. Of these, 16 are sandstones, three are highly CaCO 3 -rich silts and carbonate rocks, and one is an olivine-magnetite-rich basalt. Eight of the sandstones have been point-counted in an effort to determine compositional trends. Sample numbers, lithologies, and locations are summarized in Table 1, and locations are shown in Figure 1. Dr. Joe S. Creager of the University of Washington kindly provided the dredge samples and thin sections for study.

Alaska↗