20 Aug 2008, The Brocade
Last year I gave a presentation at a boys' school in Virginia - although to call Woodberry Forest a school is a bit like calling the Pacific a puddle. It was a magnificent school - gorgeous buildings situated in rolling green parkland. I got to stay in a beautifully appointed guest house. The boys were polite, interested, fun. But best of all I came away feeling I had made some friends - particularly two of the teachers, who just happen to be married to each other.
Earlier this year those two teachers and I got together again in California and as we were driving along I-280 Michael gave a fascinating description of the San Andreas fault, visible to the left of the highway. It was then that I decided I was going to ask him to write something about the land that lies hidden far beneath the Pacific - the ocean bed. Here is what he had to say. I found it fascinating, and I hope you enjoy it too. It certainly adds an extra dimension - of time and geology - to my journey.
When my friend Roz first asked if I would be willing to write an essay about the geologic story that (quite literally) underlies her journey across the Pacific, my first reaction was probably very similar to that of many people who are reading this: She's crossing the Pacific OCEAN! After departing the California coast, Roz won't see another rock until she makes landfall in Hawaii. That doesn't exactly make for an engrossing geologic narrative. But Roz was persistent (what a surprise!) and, the more I thought about it, the more I realized that geology does provide an interesting and unique perspective on her Pacific voyage. What follows is a rough geological "sea log" of the first leg of this remarkable adventure.
*Kilometer 0:*
As Roz passed beneath the Golden Gate Bridge, her attention was quite understandably on the treacherous currents that swirled around her and the enormity of the challenge ahead. I doubt she spent much time looking at the rocks of the Marin Headlands to the north, and I'm certain she didn't realize that those very rocks had made the same journey she was attempting-only in the opposite direction!
*Picture 1.* View of the Golden Gate Bridge and San Francisco from the Marin Headlands. Rocks in the foreground are radiolarian cherts of the Franciscan Formation. Photo - Michael Follo.
The Marin Headlands are what geologists refer to as an *exotic terrane*. They are comprised of rocks-in this case bedded cherts of the Franciscan Formation- containing the remains of microscopic marine organisms known as radiolaria. Some terranes are thought to have originated as far away as the southern hemisphere and/or western Pacific. Movement of the Earth's tectonic plates transported these terranes thousands of kilometers. When the plate carrying the Franciscan cherts slid beneath western North America in a process known as subduction, oceanic rocks on the descending plate were scraped off and accreted to the North American continent. Intense folding of rocks in the Marin Headlands is evidence of the force of this collision and uplift.
Thankfully for Roz, her voyage differs from that of the Marin headlands and other exotic terranes in speed as well as direction. The average rate of plate motion is approximately 5 centimeters per year-about the rate at which a fingernail grows. On even her worst days, fighting headwinds and currents, Roz is well over a hundred million times faster!
*Kilometer 10:*
Not long after paddling out of San Francisco Bay, Roz crossed a major tectonic feature, the San Andreas Fault - a *transform* plate boundary along which the North American and Pacific plates slide past one another. The movement along this boundary is primarily responsible for the numerous earthquakes that residents of California are all too familiar with. There are two other types of plate boundaries-*divergent*, where two plates move apart and new crust is created, and *convergent*, where two plates come together and crust is recycled as one plate subducts beneath the other.
*Picture 2.* Google Earth image showing approximate trace of San Andreas Fault (red line) where it crosses from the San Francisco peninsula to Point Reyes.
Roz's Pacific voyage is very different from that of her earlier row across the Atlantic. The Atlantic Ocean is bisected by a divergent plate boundary, the Mid-Atlantic Ridge, separating the Eurasian and North American plates. They were once part of a single supercontinent, known as Pangea, which began to rift apart approximately 200 million years ago. As Europe and North America moved away from this mid-ocean ridge, the Atlantic Ocean grew progressively wider-as it continues to do today. The Earth is not getting bigger, so the amount of new crust created at divergent boundaries must be balanced elsewhere by subduction at convergent boundaries. In the Pacific, this occurs along the so-called "Ring of Fire" that circumscribes virtually the entire ocean basin.
Along this convergent plate boundary the Marin Headlands and other exotic terranes were accreted to western North America. However, complex plate interactions over the last 30 million years have transformed this formerly continuous subduction zone into the San Andreas Fault system. After crossing the San Andreas, Roz will not pass another plate boundary until she reaches the western Pacific near the end of her voyage. There, the Pacific plate collides with the Philippine and Indo-Australian plates along a complex boundary.
*Kilometer 3700*
I'm certain that Roz will be thrilled to see the Hawaiian Islands - and they provide a break from 3700 kilometers of geologic monotony. For the past several months, Roz has been rowing some 5-6 kilometers above a featureless abyssal plain marked only by occasional volcanic seamounts, all below sea level. The Hawaiian Islands, on the other hand, rise from a depth of 6000 meters to an elevation of over 4000 meters above sea level. By this measure, Mauna Loa on the Big Island of Hawai'i is the tallest mountain on Earth, surpassing even Mount Everest (8850 meters).
The Hawaiian Islands are a chain of volcanic islands extending from Kaua'i in the northwest to the Big Island of Hawai'i in the southeast and require a different explanation. The most important clues to the origin of Hawaiian volcanoes come from their age distribution and composition. The oldest volcanic rocks are found on Kaua'i. The islands get progressively younger to the southeast, culminating in the currently active Kilauea volcano on the Big Island.
The Hawaiian Islands are thought to be the product of a more or less random "hot spot," a thermal plume of mantle-derived magma that has burned its way up through the overlying plate. The Pacific plate is moving (to the northwest) over a stationary hot spot. As the plate continues to move over this, a series of volcanoes have built up and then gone extinct as each island was carried away from it.
The Pacific Plate has been moving over the hot spot at an average rate of approximately 10 centimeters per year. The prominent bend in the chain reflects a change in the direction of Pacific Plate motion some 40 million years ago. Prior to that time, the Pacific Plate was moving almost due north.
The Pacific plate is steadily carrying the Hawaiian Islands northwest at a rate of some 10 centimeters per year, the first leg of her journey is actually getting longer by the day. Sorry, Roz!
*About the author:*
Michael Follo is a science teacher at Woodberry Forest School in Virginia. He has a Ph.D. in geology from Harvard University, and has taught at the college and secondary school level for the past 23 years. He has conducted geologic fieldwork in Europe, North America, and Hawai'i-but, unlike Roz, nowhere in between.
Other stuff:
Position as at 2100 19th August HST, 0700 20th August UTC: 22 26.238'N, 151 00.378'W.
It is a beautiful night tonight. As I rowed along after sunset, waiting for the moon to rise, the deck of my boat lit up and looked up at the sky to see a shooting star. I'd never seen one so bright - it really was like a camera flash going off in the darkness of the night.
Thanks for all the great messages. Special hellos to: Brian - have a great (and safe) time mountain-climbing in Pakistan. Hope to see you in London in November. Andy, Emer, Ailis, Saoirse and Caoimhe - so nice to know you are keeping an eye on the blog. Hope you're settling into your not-so-new home. Lots of love to all. George - thanks for the quote. I used to live in the same village as Sir Peter Blake's family - I met his widow and son. Lovely people - wish I'd met the man himself, but I was too late. John, Erin - great questions. Will respond in future blogs.
And finally. from George van der Meeuwen in New Zealand: There is a legend that says: On the occasion of a great forest fire, all the animals sought to escape. Only one little hummingbird was gathering a few drops of water from the river and flying high to drop them on the fire. They asked the hummingbird what use it was to do so little? The hummingbird answered - 'If everyone were to do just a little!'
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19 Aug 2008, The Brocade
When I was on board the JUNK the other night I talked with Marcus and Joel about plastic pollution - of course. Hard not to, when the raft beneath our feet was a monument to the issue, being kept afloat by 10,000 plastic bottles lashed together in cargo netting.
And we agreed that we are not against plastics per se. Plastics have many valuable uses - apart from keeping rafts afloat, plastic is used for many other things that could not easily be substituted with any other material. Looking around the Brocade, I have plastic waterproof bags, Pelican cases, sea anchor buoy, buckets, seed sprouter, food containers and most of my electronics.
No, what we are against is not the use of plastic, it's the ABuse of plastic, particularly for items that are intended to be disposable. According to the printed cotton grocery bag the JUNK guys gave me, over one million plastic bags are used PER MINUTE world-wide. And it can take over 300 years for them to break down. That leads to some scary arithmetic if you work out how many billions or trillions of plastic bags we could end up with.
As a parallel example, I was working in Information Technology in the run-up to the year 2000, and we were all obsessed with the so-called Millennium Bug. The fear was that all computer-based systems would grind to a halt thinking that 00 signified 1900 rather than 2000. We cursed the short-sighted predecessors who had somehow overlooked the fact that the year 2000 would inevitably arrive - or at least had counted on it not arriving until they were safely retired.
And yet are we not now guilty of similar short-sightedness if we think that we can carry on producing plastic goods indefinitely, and not eventually be up to our eyes in cast-off plastics? Will future generations look back at our era and curse us for our short-sighted stupidity?
Unfortunately democracy does not encourage long-term thinking at governmental level. Plastics (like cars) are so convenient, and so integrated a part of our lives - no politician who wanted to get elected is likely take a tough stand on widespread reduction of plastic usage.
So action has to start at the grassroots level. We all need to do our bit to make a difference - and plastic bags and plastic water bottles are a good place to start. Rather than relying on recycling, let's REDUCE the amount of plastic being generated - a much better solution with a smaller carbon footprint and overall lower environmental impact. Get your re-usable grocery bags (organic cotton or bags made from recycled plastic are best) and your water filter. And do your bit to save this wonderful planet of ours.
I've said it before and I'll say it again: If we pull together, we can make a world of difference!
Other stuff:
Last chance to get me into the top 25 for the AMEX list! I need to make the shortlist to have a chance of qualifying for a share of the funds - and further funding is crucial to the second leg of my Pacific row, and the environmental documentary based on my adventure. Having just said democracy is flawed. VOTE FOR ME PLEASE!!
Position at 2100 18th August HST, 0700 19th August UTC: 22 26.722'N, 150 31.022'W.
A hot and calm day today - not conducive to high mileage, but I kept plugging away, fuelled by regular bribes of Larabars and wild salmon jerky. For a while this afternoon there wasn't a cloud in the sky and over the calm seas I could see all the way to the horizon. Blue above, blue below. The ocean looked like a very big place.
Well done to Team GB for a promising start to the Olympics. Mum sent me an update a few days ago to say we were third in the medals table. Fantastic! Congrats to all the athletes - especially the rowers.
Thank you for all the messages - and for the donations that keep on trickling in. All very much appreciated. You are kind, wonderful and generous people!
Thanks especially to Sandi for my virtual trip from Lands End to John O'Groats. So I'm in the Peak District now? I must drop in on my friend Penny in Hathersage! I love the moors around there - thank you for conjuring up happy memories of long rambles and country pubs!
Thanks, too, to John H for the links to the following articles. The oceans really are in trouble. Quite apart from the plastic pollution, see what else is happening.
*Ocean 'dead zones' expanding worldwide: study*
WASHINGTON (AFP) - Oceanic "dead zones" where marine life cannot survive have been steadily increasing over the past five decades and now encompass 400 coastal areas of the world, a US-Swedish study.
The number of these areas, in which aquatic ecosystems disappear due to lack of oxygen in the water, have "approximately doubled each decade since the 1960s," said the study in the journal Science on Friday.
SAN JUAN, Puerto Rico - A maroon-striped marauder with venomous spikes is rapidly multiplying in the Caribbean's warm waters and even off the East Coast - swallowing native species, stinging divers and generally wreaking havoc on an ecologically delicate region.
The red lionfish, a tropical native of the Indian and Pacific oceans that probably escaped from a Florida fish tank, is showing up everywhere - from the coasts of Cuba and Hispaniola to Little Cayman's pristine Bloody Bay Wall, one of the region's prime destinations for divers.
Wherever it appears, the adaptable predator corners fish and crustaceans up to half its size with its billowy fins and sucks them down in one violent gulp.
If you live in the UK and wish to make a contribution to Roz and don't wish to use Paypal, send a message from the Contact area of this website for details
Do look at the Books box Roz's latest recommendation is there, amongst many other books: Titus Groan by Mervyn Peake - or purchase it from Audible.com
Day 86 of the Atlantic Crossing, 26 February 2006: No news, no blog.
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18 Aug 2008, The Brocade
If I had a dollar (or pound) for every time I've been asked if I've read The Life of Pi, I wouldn't be needing to ask you to vote for me in the Amex grants scheme (hint!).
But although I had read it, it was quite a while ago and at the time I didn't really GET it. Today I've been listening to it as an audiobook, and if I was ever going to get it, it would be today..
The hero, Pi, finds himself on a lifeboat on the Pacific with only a tiger called Richard Parker for company. His lifeboat is almost exactly the same size as the Brocade, so as I've been rowing along and listening to his life as a castaway, his life has seemed very close to mine (although fortunately the only animals I have on board are of the stuffed variety). There is mention of sea anchors and water rationing. He even encounters a garbage patch.
Not surprisingly, the book really made sense to me today. The way author Yann Martel described the ocean and the skies really struck a chord - but even closer to home were the descriptions of boredom and terror, excitement and despair, often coming almost at the same time. There is even a line in the book that says, "The Pacific is no place for rowers"!!
But my favourite passage is Chapter 56 (I think), which starts:
I must say a word about fear. It is life's only true opponent. Only fear can defeat life. It is a clever, treacherous adversary, how well I know.
Wise words, of which there are many in this intriguing book. I'm very glad to have given it a second try.
Other stuff:
Position at 2100 17th August HST, 0700 18th August UTC: 22 38.295'N, 150 02.297'W.
It has been a very pleasant day's rowing - a few squalls and a brisk cool breeze, but they are a welcome relief from the hot tropical sun. The Life of Pi has occupied my mind, and was the perfect length to accompany a day's rowing. Whenever I find myself getting bored or impatient with rowing, I tell myself to "Go into the book" and refocus my attention on the story and away from the boredom. Or I promise myself I won't look at my watch until the end of the next chapter. It's all in the mind.
And I have crossed 150 degrees West - woohoooo!!!! Waikiki lies just this side of 158 degrees. I am now into the last 500 nautical miles. Too soon to say that the end is in sight, but it's definitely drawing nearer.
Yesterday I switched over to Hawaii Standard Time, and got rather caught out when the sun abruptly set at 1830 and I hadn't even started getting my dinner ready. Today I've succeeded in getting the hang of the new time zone. I was up at 0500 to start rowing at 0530 to make the most of daylight hours. At the time of drafting this blog it's 1830 and I'm just sitting down to my dinner (a rather grand way of saying: I'm sitting in my cabin typing this while I wait for my freeze-dried food to rehydrate in boiled water). Then a couple more hours under a nearly full moon, and that should be a fine end to a very satisfactory day.
Please try to vote on the AMEX project if you have not yet done so. BUT please don't vote more than once! We still need to push the total a bit higher.
It is easy to vote:
1. Go to the Members Project box on the right, click on Additional Information.
2. Half way down the right hand column is the invitation to be a guest - sign up.
3. Go to top right of the page and vote.
We appreciate your help, Rita Savage.
Purchase the Life of Pi from Amazon or from Audible.com
Follow the voyage of JUNK as they head towards Hawaii.
Click here to view Day 85 of the Atlantic Crossing 24 February 2006: Click the Links - Rita trying to keep people interested when there is no news from Roz.
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