Weaubleau's Round Rocks

Driving back to Minnesota with the family after Thanksgiving, Passenger attempted to amuse Driver with area factoids from Wiki and its links. We were on Highway 13 approaching Osceola, MO, which is north-northeast of Weaubleau. So that prompted a search for information on the enigmatic Weaubleau Eggs, aka “round rocks.”

Google offers this photo:

Thousands have been found in the vicinity, but they're rare elsewhere on Earth. The most common sizes run from golf-balls to grapefruit. Over the years, residents of Weaubleau and Osceola built stairways and walls from them.

Most are round or ovoid, a little flattened on one side. Cracking them open reveals that the bulk of each egg is chert, a hard, glossy sedimentary rock that results when silica replaces portions of calcium-carbonate limestone. Flint is one type of chert.

Weaubleau eggs often have a small piece of gray or greenish mudstone at the center, hence comparisons to eggs and their yolks. Sometimes the mudstone may hold the fossil of a conodont, a tiny, toothy eel. 

Round rocks sometimes occur together in ancient gravel deposits. This geology paper on the Weaubleau crater calls them shale-filled paleokarst pockets. Here's a photo from that paper:

The current consensus among the rock-minded is that the round rocks originated with a meteorite impact circa 320-340 million years ago. Given that there are three non-concentric rings visible with synthetic-aperture radar, the cause may have been two or three serial impacts in close proximity. At any rate, something produced rings of shocked rock, the largest of which is about 12 miles in diameter.

Weaubleau counts as one of the Top 50 biggest meteor impacts detected on Earth, and offers more visible remnants than the average site. 

There's another possible distinction, even rarer if confirmed. Weaubleau could be one of a near-linear string of craters along the 38th Parallel:

If these are not coincidental, the Weaubleau event would be part of the only known serial-meteorite-impact on Earth.

But this caveat: Planetary geologists say a serial impact on Earth is improbable. Given the Earth's relatively weak gravity well, compared to that of Jupiter, terrestial gravity is supposed to be too weak to break up even poorly cemented comets. So before agreeing, they'd want more proof that the 38^th Parallel craters are of the same age. 

But the Moon appears to have several crater strings from serial impacts, so it's not impossible.

Back to rock hunting. The best place to find a specimen is near the rim of the crater. North of Osceola, we turned off the main highway and found this estimable egg in a ditch:

It's a little more than seven inches in diameter, and weighs 13 pounds, so it's on the upper end of egg size. And no, we don't plan on breaking it open to see if there's a baby conodont fossil inside.

What would form such odd objects, and in such great numbers? One TV news account surmised that the eggs were formed immediately by the impact and flew like so many cannonballs from ground zero. More likely is that the impact threw out little pieces of mudstone from the crater that, in time, prompted chert formation. The phrase doesn't roll off the tongue like the term "cannonball," but rockhounds say that Weaubleau eggs are spherical nodules of chert that nucleated around siltstone clasts.

Rena's Box Score: Storms set the pace

There are hints that a newly invigorated container removal effort at the MV Rena, still grounded off New Zealand, may not have much longer to operate. 

Rena's hull is seriously cracked and likely to finish breaking in two if the weather gets bad enough. It's amazing to me that it's still in one piece at all, given that the bow has been on the rocks for more than two months while the stern remains afloat, defying tides and ocean swells.

And storms. A 30-knot storm, with 13-foot waves, is forecast for the weekend. It'll be rough if anybody's working inside:

The crane-carrying barge Sea Tow 60 has stopped trying to lift containers, moving aside for the heavy lifter Smit Borneo. Here's a picture of Borneo on its way to the port of Tauranga, NZ, taking waves in stride:

Borneo has since arrived at Rena's location. It was lifting six containers at a time with the pedestal mounted 500-ton boom, but heavy weather and then a mechanical issue suspended the crane work. Here's containerized cargo arriving on shore:

Here's the current box score ... Out of 1,368 containers on board when the ship hit Astrolabe reef:

• Still on board, mostly below deck: 1,072
• Fell off and whereabouts unknown: 65
• Fell off, but rounded up: 25
• Removed by crane: 206

Containers are still breaking away. I'll post another note after the storm passes.

RED Dawn: Digital Cameras, Moving into Movies

How often does one get to meet one's movie hero?

Not often. I did interview Harrison Ford once about his helicopter training when I was writing The God Machine, and also John Lithgow for Harvard Magazine, but those talks were by telephone, so they don't count as up-close.

The hero-meeting I have in mind was three weeks ago, when I was at a location shoot in Maine for the History Channel. The show will air for the centennial of Titanic's loss: April 2012.

The object in question is the Red One digital camera, which is something I've wanted to see since it came on the market four years ago. The Red One offers a max resolution of 4,480 by 2,304 at 60 frames per second, which is well beyond what any television can reproduce. It's movie quality.

The production unit for Lone Wolf Documentary Group was using the Red on a wheeled crane, which will give a cinema-like feel. 

An operator holding a remote control was responsible for changing the angle, focal length, and focus of the camera. Here's the business end:

Here's a profile, from the company:

Typical attachments to the body are a hi-res monitor, filter,  a battery pack, a storage device, and a carrying handle. The Red is very much a modular design.

I know there are other brands of digital cameras now capable of moviemaking, and a newer Red model, the Epic, surpasses the Red One in features like pixel array. But the One has a special place because it opened the door to more independents by greatly lowering production costs. I first picked up a Sony video camera in 1980, starting reading American Cinematographer, and wondered how long it would be before video could match the 35mm cameras from Arri and Panavision.

I talked to a technician on the set and he said the latest video equipment records light better than filmstock in some respects, including underlit scenes. Very bright spots of the image are still a challenge for video, which tends to wash them out, but bracketing can improve the rendering. 

It's not just a question of resolution; a successful product takes the right combination of lenses, sensors, mounts, image-processing software and workflow, and storage that can reliably handle the huge flows of data. The Red One started with hard-drive storage, but now flash cards are common.

There weren't many skeptics about what a Red One could do after Peter Jackson took up the company's offer to try it out. Jackson did more than play around with it: he hauled two of them to New Zealand and came back with a short-form WWI costumer called Crossing the Line, filmed in two days. It drew a lot of attention at the National Association of Broadcasters' 2007 convention. Here's a low-resolution clip from it, posted on YouTube:

Since then, many major productions have dropped film stock and gone Red, including Social Network and Contagion. Here are more titles. 

There was a long waiting list at first; now availability is better. Renting the Red One body and a package of commonly used accessories costs about $2,500 per week from an LA rental house. 

Rena's New Phase: Container-Plucking

The removal of Heavy Fuel Oil, diesel, and lubricating oil from the Rena is complete enough that the next phase, container removal, has begun.

We're told that a grand total of 1,262 containers remain on the Rena, topside and in the holds. A crane on the Sea Tow 60 has pulled off eighteen to date, after workers freed the corner attachments with cutting torches. Here's a short NZ news item with a video clip.

Pulling containers from unstable stacks and lifting them with a crane that's sitting on another ship -- a ship that's moving independently from the Rena -- is difficult and dangerous, even in the best of weather. Getting close enough to use a cutting torch and attach cables means a rigger is close enough to get smashed. 

Despite the salvor's best efforts, it's likely that hundreds of containers will end up in the water anyway, particularly if a storm comes along. And the work is so difficult and dangerous it can't be rushed with the thought of beating the storms. The best information I've seen on the ups and downs of the salvage work can be found at this blog, Antipodean Mariner. Check it out!

Six to eight containers off would be a good day, so months of fair weather would be required to get all of them off. Not too likely.

Anticipating that likelihood, Svitzer's salvors have readied two hundred transponders, and attached them to containers most likely to become flotsam.

A more substantial crane-equipped vessel, the Smit Borneo, is on its way from Singapore and should arrive in a week or two. The Smit Borneo is a heavy-lifter, usually employed for pipelaying in the offshore oil patch. Here's an issue of a Smit publication, The Tug, that mentions the Borneo at work on a sunken drill rig. Here's the vessel, from VesselTracker.com:

A look at the Rena makes the challenge clear. Containers were stacked seven high aft of the deckhouse, and up to six high elsewhere. There are hundreds more containers secured in steel racks called "cell guides," under the decks.

For container geeks, here's a handbook for vessel masters about how containers are stowed on different types of ships, above and below decks. Here's a risk-advisory paper from marine insurers on the problems of container stowage above decks. (Item for future blog: marine insurers are concerned about a rising trend of containers lost from containerships while in transit; there are a variety of reasons for this; one is a scary phenomenon called parametric rolling.)

First, a brief summary about how generic containerships like the Rena stow their cargo. At port, crews begin by lowering and stowing containers in the holds (the cavernous areas below decks). When each hold is full, cranes lift heavily reinforced covers to seal the hatches. These hatch covers are the foundation for hundreds more containers on deck, usually six high. 

Containers in the holds: Each vertical column of containers is called a “cell.” As lowered by a crane, a container slides down a “cell guide" (a strong steel framework with vertical tracks) until it comes to rest either on the base of the cell guide, or another container. 

Containers are highly standardized, which allows the dimensions of the cell guides to be very precise. Precision is normally a good thing, because if there's slack between the cell guides and the containers, movement of the containers at sea will damage the cell guides.

Above decks, the first two or three tiers of containers are held down by steel rods called lashings. These are diagonal tension rods, securing corners of the containers to fittings on the ship structure. These attachments are quite strong ... assuming the containers and fittings are in good shape. If you look at the Rena photo above you can see some of the diagonal lashings -- they look like X's across the ends of the containers.

But containers in tiers rising higher than the lashed ones are more at risk. These upper containers attach to each other at the corners, not directly to the ship structure. The higher and heavier the stack, the more leverage to crush the containers below, or to snap their attachments. Crushed containers are visible at the bottom of the stacks on the stern.

Chasing Contrails at Flight Level 360

Disaster-wise, I'm tracking several developments (evidence of spontaneous fission at Fukushima-Daichi; what went wrong with Fobos-Grunt after successful injection to low-Earth orbit; and the daring plan to pluck shipping containers from the leaning Rena with the Smit-Borneo crane barge) but for now, a word about my sponsor, clouds! This following two trips to California in the last two weeks.

One trip was for an Inviting Disaster safety talk at a NASA facility and the other was to finish location shooting for a History Channel special to be broadcast in April 2012, produced by Lone Wolf Documentary Group. Links to come.

Both flights offered fine weather, which for a cloud-watcher, means heaps of clouds below and a clear sky above. 

One neat back-lighting effect that appeared west of Salt Lake City was produced as sunlight reflected off the snow cover, sending sunlight up through a heavy cloud cover:

And contrails clamored for attention, like these two eye-level streaks at 36,000 feet:

Here's a sunrise-contrail, appearing when I was on the way back:

Here's a contrail as seen from above, also in early morning.

Over eastern Utah our flight paralleled another plane, which happened to be making a whopper of a contrail. The sky was hazy enough, and the contrail big enough, that it actually threw a shadow across the sky:

 

Here's the dark streak that the contrail laid across a low cloud deck and a range of mountains:

That's a big one. More typically, contrail-shadows are faint and not visible at long distances, like these:

Winding up, now back at ground level, here's a summertime time-lapse video of cirrus on a northwesterly wind, followed by a handful of contrails.

Lotsa flotsam: Crane vessel joins the Rena scene

Quick DW sitrep: The Rena will never float again, or not in one piece, but at least it's holding together at its location on Astrolabe Reef, so far. There's some progress in pumping the heavy fuel oil and diesel out of the tanks: 256 metric tons so far. That's out of the port-side tanks, which are a lot easier to reach than those on starboard side.

The work on the inside is truly miserable: a sickening smell of rotting food and oil; very slippery ladders and stairways tilting beyond 20 degrees; the danger of getting flattened by something breaking loose.

And then there's the noise. If the salvors have a spare moment to make an audio recording and send it to someone like me, it would do justice to a techno-haunted house. As each wave hits, those on the inside say it raises an unearthly chorus of shrieks, groans, and grinding noises. "Cacophony" is the word that comes to mind, but it's not strong enough. This description from Svitzer spokesman Matt Watson:

"When you are up close to it, it sounds like Jurassic Park - you hear this groan, and then a crack, and then a roar like she's kind of writhing in the water.… It runs from one end to the other and then it just seems to ricochet back. It's a very interesting sound, to say the least."

As to the crane-vessel question that I raised in this post, now we know the name of the ship hired by marine salvor Svitzer to round up containers from the Rena: the Pancaldo. Here's a picture from MarineTraffic:

According to RadioNZ, the Pancaldo will start by hoisting stray containers aboard (that's flotsam, meaning debris floating in the water). Here are containers setting out on their voyage, which could reach South America if not picked up first:

Whenever Pancaldo pulls a sunken container off the seafloor, it's got a grip on lagan. Lagan includes containers that its cranes pluck from the tilting deck of the wreck.

But it won't be bringing back jetsam: that's because admiralty courts say jetsam is only that that stuff that a crew physically heaved overboard to lessen the draft. Months from now, when you're trying to keep all these straight, think of jetsam as something that is jettisoned.

These kind of details may seem like nit-picking to the rest of us, but in legal history it's meant a good deal in fights involving claimants who came across extremely valuable cargo: was it free for the taking, or did it belong to the salvor, the insurers, or the vessel owner?

Why Rena carried two grades of fuel oil

The Containership Vessel Rena hasn't broken in half yet, but the hull is seriously fractured, given the flexing of the ship. Here's a diagram from Maritime NZ showing how the ship sits half-on, and half-off, Astrolabe Reef. The bow is on the right:

Each technological disaster and close call offers a window into how systems work, and how they fail. The grounding of the Rena is an opportunity to learn about the modern combination of fuel and machinery that makes big ships get up and go.

By the early 1900s, the most common approach to powering a steamship was coal-> steam-> reciprocating engine. Ships carried thousands of tons of coal in storage compartments called bunkers, and men called coal trimmers shoveled it within reach of firemen, who heaved it into fireboxes, which heated a bank of boilers to raise steam. Later, shipbuilders turned from reciprocating engines to the more compact and powerful steam turbines. 

Loading and handling coal on board ship was a nuisance, dirty, and labor-intensive. Coal for bunkering ships began a long decline following the amazing discovery of Spindletop Field near Beaumont, Texas, in 1901. Ships began experimenting with crude oil, but the quantities required were large and oil had better uses. Steamship engineers turned to steam-generating systems that burned the cheapest grade of petroleum-derived fuel, a tarry residue from refining called Bunker C. 

Some power plants use similar stuff today; it's called No. 6 Fuel Oil, or a blend of No. 6 and No. 2.

Number 6 and Bunker C must be heated before pumps can force the stuff from storage tanks, through pipes, and into burner heads mounted under the boilers. Normally this is not a problem, since ships have a surplus of waste heat and use it to keep the tanks hot.

Later, shipbuilders began moving away from steam plants to marine diesels, but those gulped expensive diesel fuel. Filling an ocean-going tugboat with a load of diesel can cost upward of $30,000.

What to do? Big ships with diesel engines, and now some big tugboats, turned to a heavy fuel oil (called HFO) similar to Bunker C, heating it and injecting it at high pressure into the cylinders of a diesel engine. 

In a busy containership or tanker harbor, a crowd of heavy-fuel-oil-burning ships would contribute much to local haze. Many ports, such as Long Beach, California, prohibit ships from burning it in their waters. One legal solution is for a ship to carry a smaller quantity of gasoil or diesel fuel for harbor use, because these burn (relatively) more cleanly in marine diesel engines. (The biggest of shipboard diesel engines are very big, weighing 2,300 tons.)

Here's what a smoke plume from untreated heavy fuel oil looks like, when burned in an urban setting (photo from the Environmental Defense Fund):

So that's why the Rena approached Astrolabe Reef on October 5 with two kinds of fuel in its bunkers: 1,400 tons of cheap heavy fuel oil, and 300 tons of diesel to use where HFO is banned, like harbors and Antarctic waters.

Once the ship lost power, the heavy fuel oil started cooling and congealing. Here's what HFO looks like when washed up on a New Zealand beach:

There's about a thousand tons of such goo still on Rena, so we can only hope the salvors can get their augers and steam-generators working and force it from the tanks before the ship breaks in two.