Sunday, June 10, 2012


Job 38:8-9
Or who shut up the sea with doors, when it brake forth, as if it had issued out of the womb?When I made the cloud the garment thereof, and thick darkness a swaddlingband for it,

After the aphotic zone, there’s complete darkness. From 1,000 meters below the surface, all the way to the sea floor, no sunlight penetrates the darkness; and because photosynthesis can’t take place, there are no plants, either. Animals that live in the abyssal zone feed on detritus raining down from above—or on each other. And sometimes they make their own light; certain species of deep sea fish and jellyfish have special light-producing cells.

the bottom of the ocean, there is no natural light. The pilots plot the position of the sub with both standard navigation equipment and with special topographical (or 3-D) maps that are made by side scan sonar. To find a specific site, the pilots use the 3-D maps, but they must also rely on visual clues. Visual work is difficult because they only have the light of the sub. Imagine looking for rock samples on land in total darkness, with only a flashlight—things seem to suddenly loom out of the blackness, and it’s hard to see enough to find what you’re looking for. These folks are often trying to find a single small probe, only a couple meters in length, or a specific spot they’ve visited before. Talk about a needle in a haystack! So it’s quite helpful to have a pilot who knows the area well; it’s a bit like when you hike—you look at the map, but even the best map doesn’t show the individual trees that you recognize as you become familiar with a specific place

The oceans are divided into two broad realms; the pelagic and the benthic. Pelagic refers to the open water in which swimming and floating organisms live. Organisms living there are called the pelagos. From the shallowest to the deepest, biologists divide the pelagic into the epipelagic (less than 200 meters, where there can be photosynthesis), the mesopelagic (200 - 1,000 meters, the "twilight" zone with faint sunlight but no photosynthesis), the bathypelagic (1,000 - 4,000 meters), the abyssopelagic (4,000 - 6,000 meters) and the deepest, the hadopelagic (the deep trenches below 6,000 meters to about 11,000 m or 36,000 feet deep). The last three zones have no sunlight at all. 

Benthic zones are defined as the bottom sediments and other surfaces of a body of water such as an ocean or a lake. Organisms living in this zone are called benthos. They live in a close relationship with the bottom of the sea, with many of them permanently attached to it, some burrowed in it, others swimming just above it. In oceanic environments, benthic habitats are zoned by depth, generally corresponding to the comparable pelagic zones: the intertidal (where sea meets land, with no pelagic equivalent), the subtidal (the continental shelves, to about 200 m), the bathyal (generally the continental slopes to 4,000 m), the abyssal (most of the deep ocean seafloor, 4,000 - 6,000 m), and the hadal (the deep trenches 6,000 to 11,000 m). 

There are several types of deep benthic surfaces, each having different life forms. First, most of the deep seafloor consists of mud (very fine sediment particles) or "ooze" (defined as mud with a high percentage of organic remains) due to the accumulation of pelagic organisms that sink after they die. [Unlike the shoreline, sandy habitats are rarely found in the deep sea because sand particles, created by wave action on coral and rocks at shorelines, are too heavy to be carried by currents to the deep.] Second, benthic areas too steep for sediment to stick are rocky. Rocky areas are found on the flanks of islands, seamounts, rocky banks, on mid-ocean ridges and their rift valleys, and some parts of continental slopes. At the mid-ocean ridges, where magma wells up and pushes seafloor tectonic plates apart, even flat surfaces are rocky because these areas are too geologically new to have accumulated much mud or ooze. Third, in some areas certain chemical reactions produce unique benthic formations. The best known of these formations are the "smoker" chimneys created by hydrothermal vents, which are described in detail below.


Darkness was upon the face of the deep After the aphotic zone, there’s complete darkness. From 1,000 meters below the surface, all the way to the sea floor.

And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.(Genesis 1:2)

Exploration of these zones has presented a challenge to scientists for decades and much remains to be discovered. However, advances in technology are increasingly allowing scientists to learn more about the strange and mysterious life that exists in this harsh environment. Life in the deep sea must withstand total darkness (except for non-solar light such as bioluminescence ), extreme cold, and great pressure. To learn more about deep-sea marine life, sophisticated data collection devices have been developed to collect observations and even geological and biological samples from the deep. First, advances in observational equipment such as fiber optics that use LED light and low light cameras has increased our understanding of the behaviors and characteristics of deep sea creatures in their natural habitat. Such equipment may be deployed on permanent subsea stations connected to land by fiber optic cables, or on "lander" devices which drop to the seafloor and which are later retrieved (typically after a radio command activates the dropping of ballast so the lander may float up.) Second, remotely operated vehicles (ROVs) have been used underwater since the 1950s. ROVs are basically unmanned submarine robots with umbilical cables used to transmit data between the vehicle and researcher for remote operation in areas where diving is constrained by physical hazards. ROVs are often fitted with video and still cameras as well as with mechanical tools such as mechanical arms for specimen retrieval and measurements. Other unmanned submarine robots include AUVs (autonomous undersea vehicles) that operate without a cable, and the USA's new Nereus , a hybrid unmanned sub which can switch from ROV to AUV mode and which is currently the world's only unmanned submarine capable of reaching the deepest trenches. Third, manned deep sea submersibles are also used to explore the ocean's depths. Alvin is an American deep sea submersible built in 1964 that has been used extensively over the past 4 decades to shed light on the black ocean depths. Like ROVs, it has cameras and mechanical arms. This sub, which carries 3 people (typically a pilot and 2 scientists), has been used for more than 4,000 dives reaching a maximum depth of more than 4,500 m. France, Japan and Russia have similar manned scientific submersibles that can reach somewhat greater depths, while China is currently building one to reach 7,000 m.

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