U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin, Barrow to Barrow. Cruise Report

U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin CRUISES HE-0302 August 30 to September 11, 2003 Barrow, AK to Barrow, A

The origin of fine scale acoustic stratigraphy in deep-sea carbonates

In this paper we investigate the origin and geologic significance of the closely spaced high-frequency subbottom acoustic reflectors characteristic of pelagic carbonates. A detailed survey was conducted of a small area in the equatorial Pacific with the Marine Physical Laboratory\u27s Deep-Tow instrument package, providing high-resolution 4-kHz profiles and precise positioning of core samples. The cores were sampled at closely spaced intervals for sound velocity and saturated bulk density. Acoustic impedances were calculated, and a reflection coefficient log determined for the upper 10 m of the sediment column. The reflection coefficient log revealed no interfaces with large reflection coefficients that correlated with the reflectors seen on the Deep-Tow 4-kHz seismic profile. The calculated reflection coefficients were very low (typically 10−3–10−5) and varied about a wavelength that was on the order of the wavelength of the 4-kHz pulse, implying that interference plays a role in the composition of the seismic record. Convolving the outgoing 4-kHz pulse with the reflection coefficient log generated a synthetic seismogram that very closely resembled the 4-kHz reflection profile. Varying the frequency of the outgoing pulse changed the amplitude and position of the reflectors seen on the synthetic seismograms. Thus we conclude that the reflectors seen on the 4-kHz seismic profile were not caused by discrete geologic horizons but rather are the result of the interference of many small layers

U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin. Cruise Report for 2004

U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin CRUISES HE-0405 October 6 to October 26, 2004 Nome, AK to Barrow, A

U.S. Law of the Sea Cruise to Map and Sample the US Arctic Ocean Margin

U.S. Law of the Sea cruise to map and sample the US Arctic Ocean margin CRUISE HEALY 1202 August 25 to September 27, 2012 Barrow, AK to Dutch Harbor, A

U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin. Cruise Report for 2008

USCGC Icebreaker Healy (WAGB-20) U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin CRUISES HE-0805 August 14 to September 5, 2008 Barrow, AK to Barrow, A

U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin, cruise report for 2009

U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin CRUISES HE-0905 August 7 to September 16, 2009 Barrow, AK to Barrow, A

U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin

U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin CRUISE HEALY 1102 August 15 to September 28, 2011 Barrow, AK to Dutch Harbor, A

U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin. Cruise Report for 2008

USCGC Icebreaker Healy (WAGB-20) U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin CRUISES HE-0805 August 14 to September 5, 2008 Barrow, AK to Barrow, A