Description not available.

Description not available.

Description not available.

A time series of six sonar images collected over gaseous seeps at Biloxi Dome. The yellow-green vertical columns are seeps of gas bubbles emitted from the seafloor (red). Note changes in seep intensity through time and the appearance of "bursting" behavior denoted by the arrows.

A gas capture device, called the methane bucket, was assembled and deployed on the Little Hercules. The methane bucket allows for estimating the volumetric flow rate associated with bubbles of methane gas at natural seeps. The methane forms a mix of hydrate (methane ice) and gas at depth but when brought to the surface the hydrate dissociates allowing measuring gas volume.

The Little Hercules remotely operated vehicle, outfitted with a 'methane bucket' capture device, captures gas bubbles percolating up from a seafloor gas seep.

Photo #1 of sequence showing capture of methane gas which forms hydrate at the top of the methane bucket.

Photo #2 of sequence showing capture of methane gas which forms hydrate at the top of the methane bucket.

Photo #3 of sequence showing capture of methane gas which forms hydrate at the top of the methane bucket.

Broken mussel shells at the site of a cold seep.

Natural gas seep imaged with acoustic sounding technology. Red line is bottom profile.

The methane bucket deployed over a methane seep with live mussels and a large red crab (Chaceon quinquedens) in the background. Note bubbles in chamber and methane hydrate formed at top of container.

The methane bucket deployed over a methane seep with live mussels and a large red crab (Chaceon quinquedens) in the background. Note bubbles in chamber and methane hydrate formed at top of container.

A 'methane bucket' capture device added to the front of the Little Hercules r remotely operated vehicle with gas hydrate (shiny material) at the top of the cylinder. During ascent, the hydrate was seen to sublimate to gas and expand in volume, filling the gas cylinder.

Launching Little Hercules from the after deck of the OKEANOS EXPLORER. A calibrated grid is attached to the ROV on its right in this image. It will be used to measure the rate of methane gas emission from a cold seep site.

A calibrated grid attached to the front of Little Hercules in order to collect imagery data that will allow scientists to assess sizes and rates of bubble escape from natural methane seeps.

An aggregation of mussels and a lone urchin at a cold seep site.

Preparing to deploy a calibrated grid for measuring rate of methane emissions at a cold seep site. Serendipitously a comb jelly is seen below the right side supporting arm of the grid.

Bubbles of methane gas rising through a mussel bed at the Pascagoula Dome seen silhouetted against a calibrated grid.

Bubbles of methane gas rising through a mussel bed at the Pascagoula Dome seen silhouetted against a calibrated grid.

Bubbles of methane gas rise through a mussel bed at the Pascagoula Dome and are seen silhouetted against a calibrated grid.

Bubbles of methane gas rise through a mussel bed at the Pascagoula Dome and are seen silhouetted against a calibrated grid.

Bubbles of methane gas rise through a mussel bed at the Pascagoula Dome and are seen silhouetted against a calibrated grid.

Bubbles of methane gas rise through a mussel bed at the Pascagoula Dome.

Methane bubbles rising from a seep area.

Methane bubbles rising from a seep area.

Three bubbles of less dense than water hydrocarbon gas and fluids escaping from an oil, gas, and brine seep area. The left-most bubbles seem to have escaping material that is leaving a trail of the bubble trajectories through the water column.

A closeup of a bubble of hydrocarbon gas and fluids escaping from an oil, gas, and brine seep area.

Small mounds or volcanoes around the periphery of a brine pool rose small heights (centimeters) from the seafloor. Some of these small volcanoes were emitting gas, probably also mixed with liquid hydrocarbons and brine. Is the brown material covering the black oil a mineral precipitate or is it of biological origin?

A small "volcano" around the periphery of a brine pool rose small heights (centimeters) from the seafloor. Some of these small volcanoes were emitting gas, probably also mixed with liquid hydrocarbons and brine. Note the bubble of gas rising from the small volcano reflecting the lights of Little Hercules giving an illusion of eyes staring back at the camera.

Globules of tar and white bacterial mat at a natural oil seep. The white specks seen above the black background are probably copepods. In the left upper center a bristleworm is crawling over the bacterial mat.

Globules of tar and white bacterial mat at a natural oil seep. The white specks seen above the black background are probably copepods. The bristle worm seen in image expl8356 has moved further up the mound and can be seen in the upper center of the image. This movement occurred over a period of six minutes between images.

Globules of tar and white bacterial mat at a natural oil seep. The white specks seen above the black background are probably copepods.

Amphipod and translucent worm tube associated with white spongy material at oil seep site on the seafloor.

Filaments of bacterial material and white mats of bacteria material at a natural oil seep site on the seafloor.

Small tar stalagmite appearing structures caused by a natural oil seep on the seafloor.

Stalagmites of tar rise from the seafloor with a surrounding white bacterial mat.

Small tar stalagmite appearing structures caused by a natural oil seep on the seafloor.

Stalagmites of tar rise from the seafloor with a surrounding white bacterial mat.

Small tar stalagmite appearing structures caused by a natural oil seep on the seafloor.

Stalagmites of tar rise from the seafloor with a surrounding white bacterial mat.

An aggregation of vestimentiferan tubeworms (Lamellibrachia sp.). Such aggregations provide habitat for smaller animals such as the small white anemones covering the tube worm tubes, and the shrimps Alvinocaris muricola. The tiny white spots all around the tubeworms are copepods, tiny swimming crustaceans.

An army of tiny white copepods flitting about over an aggregation of vestamentiferan tubeworms (Lamellibranchia sp.). Such aggregations provide habitat for smaller animals such as the small white anemones coverning some of the worm tubes and the shrimps Alvinocaris muricola.

First map of an oceanic basin. Matthew Fontaine Maury produced this map in 1853 and published it in the Wind and Current Charts for that year.

Second map of an oceanic basin. Matthew Fontaine Maury produced this map in 1854 and published it in the Wind and Current Charts for that year. This map had significantly more data than the 1853 map including soundings by Lt. Otway Berryman, USN, on the USS DOLPHIN over the Mid-Atlantic Ridge (MAR) north of the Azores. These were the first soundings on the MAR.

Bottom characteristic map of the approaches to New York Harbor by "United States Hydrographical Office" as published in Matthew Fontaine Maury's Wind and Current Charts for 1858. Data from United States Coast Survey. Note there is no expression of Hudson Canyon below the continental shelf break although the channel of the Ice Age Hudson River is clearly shown.

First profile of an oceanic basin. Matthew Fontaine Maury produced this profile in 1854 and published it in the Wind and Current Charts for that year.

An early example of a microscopic examination of ocean bottom sediment. This was published with a report by Lt. Joseph Dayman, RN, who ran a line of sounding s across the Atlantic Ocean from Newfoundland to Ireland on HMS CYCLOPS in 1857. This was the second line run and covered the same ground sounded by Lt. Otway Berryman for the USCS on the ARCTIC in 1856.

Sounding on the HMS CYCLOPS in mid-Atlantic Ocean in August 1857. The diagram on the right shows the problem with early hemp sounding line methods. The line would keep running out after reaching bottom and the surveyors would not be able to ascertain an accurate depth.

Top panel same as image map00006. Bottom panel demonstrates method of detaching weight and retrieving bottom sample such that the surveyor would at least know that the sounding weight had reached bottom. However, this did not improve the accuracy of the sounding.