Pitcairn, Feodor (Producer). 2008. Ocean Odyssey, Public Broadcasting System, Smithsonian

Pitcairn, Feodor (producer). 2008. Ocean Odyssey, Public Broadcasting System, Smithsonian Institution National Museum of Natural History, 57 minutes.

Commissioned by the Smithsonian Institution’s National Museum of Natural History, this film explores a series of stunning marine ecosystems along with the variety of life that inhabits them. Photographers Feodor Pitcairn and Bob Cranston visited some of their favorite sites to document what can be seen in these intact ecosystems before increasing pressures change them.

The Galapagos Islands (off the west coast of Ecuador, South America) represent a unique marine environment. The cold current comes up along South America’s west coast, a warm El Nino current arrives from the west, geothermal heat and chemicals rise from the East Pacific Rise rift zone, upwelling brings nutrient-rich cold water to the surface where it nourishes algae, and organisms who arrive at the islands adapt to the environment. Unique endemic species found nowhere else, like the marine iguana lizard. Large schools of hammerhead sharks rise up from deeper waters.

The Channel Islands, off the coast of Southern California, are encircled by lush kelp forests. The towering brown algae can grow up to one foot a day, and provide a rich environment for many species, including the nest-protecting orange garibaldi fish, and the once nearly extinct giantblack sea bass that reaches more than 6 feet in length and 500 lbs. The strange looking MolaMola (or ocean sunfish) with their rounded tail fin, and their 14 foot dorsal to pectoral fin span are examples of the unusual fish that inhabit the area. These habitats are just now recovering from years of overfishing.

The spectacular pristine coral reef in Raja Ampat, Indonesia, is teeming with life. There are many mutualistic (mutually beneficial) associations in the reef, including the association between damselfish and the coral colonies where they hide for protection. Many fish wait in place, letting the current bring food to them. The lionfish, seen here, is now a pest in Florida. Though exploding with life, a rise of just 1 degree C can destroy such a reef.

The Azores, in the Atlantic Ocean, are a place where sperm whales, the largest toothed mammal, and sometimes congregate in social groups. Though they can be docile and friendly, they have also been known to ram an sink large ships. Loggerhead turtles feed on scraps of octopus leftover from feeding sperm whales. Other whales such as the humpback whale migrate thousands of miles, singing to each other across large expanses of ocean. Calves play and stay with their mother for a year.

Off the coast of India, giant manta rays (with a wingspan of 22 feet) travel with remoras attached to them, and stop at a cleaning station where smaller fish remove parasites. The court and perform feeding loops, filtering small mysid shrimp from the water – funneling water into their mouths with special fins.

Other impressive views include the dozens of varieties of small “bait” fish that take advantage of the rich upwelling water to feed, moving as waves of glimmering bodies. Mobulas (relatives of the manta rays) come here to feed as well. Herring move as one, and are one of the most important food fishes. The jacks and tarpon come to the herring shoal to feed. In the Caribbean off the coast of Belize, Central America, whale sharks filter eggs and sperm broadcast into the water by spawning fish. Immediately following the full moon, various species of jacks and snappers form large spawning groups, releasing their spawn into the water. Similarly, the coral reef off the coast of Texas cue into the summer moon’s blue light, transforming the reef by synchronous spawning. The orbs produced will float off to start new coral colonies.

Intelecom (producer).1992. Birth of a Theory, episode #5, from The Earth Revealed, Annenberg Media, with James Sadd (Occidental College), 30 min.

In the 1960s, earth scientists developed the theory of plate tectonics. This program traces the development of plate tectonics, beginning with the contributions and methods of geologist Alfred Wegener. Sea-floor spreading, continental drift, paleomagnetism, and the primordial supercontinent Pangaea are covered.

Earth is composed dynamic planet composed of an outer skin of rigid plates that slide
on molten layer beneath.

1912 -- Alfred Wegener first proposed the idea of mobile continents (evidence included identical rocktypes, fossils, glaciation zones & minerals deposits that occur across ocean basins).

Gondwanawas an early "supercontinent" of united current-day Southern Hemisphere continents.

Wegener could not adequately define a process that could account for the observed movement.

Hess ran his fathometer continuously during WWII, leading to his discovery of sea floorspreading, based on his observation of guyots (submerged flat-topped seamounts) whichwere eroded away the further you got from mid-ocean ridges.

Sea floor spreading occurs at mid-ocean ridges, with subduction occurring at deep ocean trenches along ocean margins where the sea floor meetsthe continents.

Paleomagnetism reveals mirror images of periods of reversals in the Earth's magnetismon either side of the mid-ocean ridges (in studies pioneered by oceanographers Vine & Matthews, Wilson & Sykes).

Spreading producestransform faults along the ridges to accommodate plate movement. Their existence also demonstrates spreading is occurring (as studied aboard the R/V Glomar Challenger).

Robert & Palmer introduced the term "Plate Tectonics" which is considered to be the unifying theory of Earth Systems Science, although questions remain about the mechanisms & processes underlying plate movement.

PBS (producer). 1995. Plate Tectonics: The Hawai’ian Archipelago, NOVA, from Hawai’i - Born of Fire, WGBH, 5 min.

Most of the phenomena associated with plate tectonics occur along the plate boundaries, including volcanic eruptions. However, the Hawai’ian eruptions do not fit this pattern. These eruptions are thought instead to be associated with a phenomenon known as a hotspot. This short video clip shows how the placement of the volcanic island chain is thought to trace the movement of the Pacific plate over a stationary plume of magma.

The Hawai’ian islands are not part of those that ring the Pacific.

They are instead formed over a fixed plume of superheated rock (magma) that comes up through the mantle and reaches the surface as a hotspot. Such plumes rise from the core or an area of high radioactivity.

Where the magma erupts through the sea floor it creates new land, leading to the world’s largest volcano, Mauna Loa, and its neighbor, Kilauea.

The Pacific sea floor is slowing drifting NW over the fixed hotspot creating a chain of volcanoes (an archipelago).

The plate has been moving for 70 million years, leading to a series of submerged extinct volcanoes, and a new volcano (Loihi) which won’t reach the surface of the ocean as an island for a couple of thousand of years.

PBS (producer). 2009. Earthquakes in the Midwest, NOVA Science Now, with Neil DeGrasse Tyson (exec. ed.), WGBH, 13 min.

Another instance of tectonic phenomena not associated with plate boundaries are earthquakes in North America’s Midwest. Unlike California quakes, which occur where plate margins slip past or under each other, these large dangerous quakes occur through processes that aren’t well understood. Evidence from caves show that they have been happening for thousands of years, and a big dangerous quake will undoubtedly happen again, perhaps in the near future.

When tension along the edges of a tectonic plate gets too great, the plates slip causing an earthquake. But another mechanism may cause a big dangerous quake in the heartland of America.

Deep in a cave in Illinois, stalagmites may reveal information on the biggest looming quake in the U.S.A.. 200 years ago, the region near Memphis, TN (New Madrid, MO) was rocked by 3 huge quakes (1811-1812), though no big cities existed there at the time. These were some of the biggest quakes in North America, and were felt from Mexico to Canada.

These quakes show up in the shifts of the rings of layers of crystal that form as the drips from the ceiling of the cave that deposit them move because of the quake. Chemical analysis of the crystals is used to determine the date of the layers, showing that there is a pattern of quakes that has been going on in the New Madrid Seismic Zone (NMSZ) for 15,000 years.

200 small (imperceptible) quakes a year show that the region is very active, as it sits over a “failed” rift zone. Moreover, sediment in the Mississippi River bed shows deformed layers that are outside the NMSZ, suggesting that the quake area may jump again. A repeat of these large quakes would be catastrophic, with 12 million people in the area under- (or un-) prepared and unaware.

Intelecom (producer). 1992. The Sea Floor, episode #4, from The Earth Revealed, Annenberg Media, with James Sadd (Occidental College), 30 min.

This episode examines major sea-floor features: the mid-oceanic ridge, oceanic trenches, and fracture zones; evidence of Earth's mobile crust.

The ocean floor is an environment with no light, near freezing temperatures and crushing pressures. Specialized submersibles and remote techniques must be used to explore “planet ocean.”

Water from volcanic steam and melting comets filled ocean basins (made of relatively thin, but heavy basaltic rockthatsinks below the level of the granitic continents); and runoff weathered the land, adding salty chemicals.

Gently dipping, shallow continental shelves (2 – 70 km wide) comprise one sixth of Earth’s surface. These extend out to the continental slope (steep) with submarine canyons(valleys),continental rise (gradual, with fans of debris), and abyssal plain(flat).

The ocean bottom is continually showered by a gentle “marine snow” of pelagic sediment made of organisms’ shells, dust, and clay particles.

Volcanic peaks (lava hillsand largerseamounts) dot the seascape. A long, connected system (“baseball seam”) of volcanic mid-ocean ridges have crests with central valleys formed by fissures filled by under-sea lava flows, making for a young sea floor (only 200 million years old vs. 4 billion year old continental crust).

Stromatolites (fossilized microbial colonies of marine algae) and sedimentary rock of marine origin that have been uplifted on the continents give evidence that oceans existed early in Earth’s history. Where is the older sea floor?

As new sea floor is added at the mid-ocean ridges (sea floor spreading) the older sea floor moves outward, with the oldest sea floor back sinking back into the mantle at subduction zones, resulting in underwater trenches (where the sea floor is pulled down sharply to deep depths).

Oceanographic sampling of the sea floor includes retrieval of sediments with grabs and corers.

Echosounding(used to detect enemy submarines) bounces sound waves off the sea bottom landforms. This technique provided the first 2-D profile (return time = depth) of sea floor topography.

1983 – “Gloria” sonar technology towed behind the ship, combined with satellite location (Global Positioning System or GPS) provided a mosaic of images used to determine the composition of the sea floor for the Atlas of Exclusive Economic Zone of the United States (200 miles from the shoreline, including rights to oil, gas, and minerals (e.g., manganese nodules)).

Harvest of resources may be difficult (especially in the deep sea), and environmentally damaging.

The oceans host unique forms of life. At the mid-ocean ridges, hot vents on the sea floor (up to 350°C, but doesn’t boil due to high pressures) have organisms living on chemical energy from hydrogen sulfide (energy from the interior of the Earth rather than external sunlight energy) at these deep sea hydrothermal vents.

Understanding the sea floor will helps to determine the influence of oceans on global climate change.

Intelecom (producer). 1992. Sedimentary Rocks: The Key to Past Environments , episode #17, from The Earth Revealed, Annenberg Media, with James Sadd (Occidental College), 30 min.

Theexposed layers of sedimentary rock at the Grand Canyon and elsewhere allow scientists to peer into the geologic past. This episode explores the movement of sediment and its deposition, along with the processes of lithification, compaction, and cementation that produce sedimentary rocks. The organic components of rock are also discussed.

Two billion years of Earth’s geologic history is recorded in the sedimentary rock of the Grand Canyon, Arizona, revealing conditions at the time the sediments were deposited (climate, vegetation, position of shoreline, etc.).

Sedimentis the product of chemicalweathering andmechanical/physical weathering (forming clastic sediments), biological activity, andwind, water and ice erosion.

Size categories include (in decreasing size): boulder (rock), cobble, pebble, sand, silt and clay (the consistency of flour).

The primary surface of Earth is composed of compacted layers of sediment formed into rock.

Particles become smoothed and rounded during transport by wind, water, gravity, etc.

Depositionoccurs where water slows, with coarse grains dropping out first (sand along the beach; with mud and claydropped further offshore).

Lithificationoccurs when compactionrearranges and distorts the particles, andcementation (by dissolved minerals in the pore space) binding the particles together into rock.

Warm or shallow waters (desert lakes, lagoons) may lead tothe precipitation ofevaporitesthat form as mineralscome out of solution (e.g., calcite, gypsum, or salt deposits).

Biological processes form limestoneby way of the accumulation ofcalcium carbonate from the “shells” of dead plants, algae and animals (e.g., chalk). Diatoms and radiolarians produce glass “shells” that form chert and diatomite.

Accumulation of vegetation in bayous and swamps leads to deposits of peat, which with time and pressure are transformed into coal.

The principle of uniformity states that processes today are the same as in the past, thus you can interpret past environmentsat the time of sediment deposition; the law of original horizontality states sediments are laid down/settle in the water column in horizontal layers (with gravity).

Ripple marks, mud cracks and other features record other aspects of the ancient landscape.

The Ridge Basin (between San Andreas & San Gabriel faults) shows evidence of opening and filling with water (i.e., a spreading zone).

Valuable resources can be derived from sedimentary rock, including limestone for cement, sand, gravel, iron ore, bauxite for aluminum, and materials needed to manufacture brick, tile, and asphalt.

Intelecom (producer). 1992. Waves, Beaches and Coasts, episode #24, from The Earth Revealed, Annenberg Media, with James Sadd (Occidental College), 30 min.

This program shows the dynamic interaction of coast and the energy of the ocean. Wave types, parts, movement, and their impact on the shore are illustrated. The program also covers shoreline characteristics, currents, erosion and deposition, and discusses how the greenhouse effect could impact sea level and coastal lands.

Winds transfer energy to the water as waves – a surge of energy that is then transferred to the coast by surf.

Water in waves takes a circular motion (lifted up and forward, return down and backward) with diameter at the surface equal to wave height. The wave base (beyond which no movement occurs) is one half the wave length.

Waves are slowed by the ocean bottom, steepening the wave until it breaks as surf.

A seismic sea wave, or tsunami, is much more powerful than wind-generated waves, bringing destruction.

A wave front will bend (refraction) due to the local decrease in velocity of wave that hit bottom first, thus decreasing the angle at which waves come onshore. Waves wrap around headlands (wearing them away) and disperse into bays (filling them with sediment).

Waves approach the coast at an angle, and return with gravity, leading to a zig-zag motion, with the overall flow along the coast in a longshore current. Sand is deposited as an extension of the beach (a sand spit) and behind breakwaters, so that they must be dredged.

Low, gentle summer waves lead to a wide gently sloping beach, while energetic winter waves produce a narrow steep beach. Streams and rivers, and erosion of the coast add sediment to coastal waters. Dams trap river sediments and deprive beaches of sand.

People soon forget severe storms that happen every few decades, and build along the shore. Sea walls built for protection are a threat to beaches (they cut erosion, thus decreasing the sand supply), and are undercut. Water tank studies show irregular shapes, like natural features, help prevent undercutting by waves.