Stories of rafting and Earth's crust

A few weeks ago a friend of mine lent me two books by Erin Mckittrick: A Long Trek Home and Small Feet, Big Land. I'm not entirely sure why, but probably because a few weeks prior to that we'd talked about rafting and she'd realised that the two rafts I was talking about were pack-rafts - inflatable boats big enough to carry a person but small enough to fit in a backpack - and Erin Kckittrick has done a lot of her travelling in a packraft.

It reminded me of rafting.

It reminded me of the trips we made in Estonian winters, where we'd have to bang paddles to get rid of the built up ice and cover gloves in plastic bags so the hands wouldn't end up as drenched ice blocks instead:

Camping on the bank of Emajõgi, Estonia

Leisurely paddling on Emajõgi, Estonia

Midwinter evening on Valgejõgi, Estonia

Setting up camp overnight, Valgejõgi, Estonia

It can take a while to paddle down a river... Valgejõgi, Estonia

Then the trips around Wanaka:

A high time of my life where we drove old, banged-up cars and lived in shared flats, but bought expensive, high-tech outdoor gear and used it regularly. The way priorities were meant to be ;) 

Lake Wanaka

Lake Wanaka

Hawea river

The Man with his brother on Clutha river

The Man on Hawea river

Heading out on Lake Wanaka on a still winter's morning

Lunchbreak on an empty shore

Where a raft can easily carry, but a car can't go - a lunch, a nap, and then back into a raft and home

Having had those experiences meant that when I read Erin Kckittrick's words, I could sense some of it better. I could picture some of the terrain she has moved through:

Near Anchorage, Alaska

When she mentioned the Iditarod sled dog racers, I knew that I know some of them:

Denver glacier, Alaska

Even the cover of her book, Small Feet, Big Land - the mountain that provides the backdrop there is the mountain I named my son after.


The more stories I listen to and the more stories I get to experience myself, the more real the new stories I come across feel to me because of all the intertwined experiences, memories of smells, knowledge...

It also meant that whilst reading Erin's and her husband Hig's words on their blog last thing in the evening right after having collapsed in bed from the exhaustion of having been a parent that whole day (oh, hi kids!), I came across a fascinating story about what would happen if earthquakes stopped:

"Question: are earthquakes an inevitable “side-effect” of a planet that can support life, or can you imagine a planet whose surface is stable enough that it never quakes the way ours does?

Answer: /.../ One way to look at it is to imagine what would happen if you shut off tectonics on earth and then watched what happened.

For a while (tens to hundreds of millions of years I’d guess) it wouldn’t be a problem. No more volcanic eruptions would reduce nutrient input into some ecosystems, but similar nutrients could be derived from mountain erosion.

Gradually erosion and deposition would lead to a planet dominated by ocean and broad coastal plains with rounded upland hills and low mountains. At this point the rate of erosion would be dropping off because the softer sediment would already be eroded, and steep slopes where erosion is enhanced would be reduced. This means that the mineral portions of soils, and dissolved minerals in groundwater, would be becoming less and less. Also without upland sources rivers would be sluggish and low oxygen. Beaches would be broad and muddy, and tides would be damped by broad shallow seas along the coastlines. This is a planet where diversity is reduced, but life is likely still abundant.

Next the land would vanish, eroded away by the ocean. The ocean floor is covered in a layer of clay, sealing off any geologic nutrient sources. Life would have to evolve to make use of a narrower spread of chemical building blocks, but would still have sunlight as an energy source.

This picture is built around the impossible scenario where tectonics on the earth get shut off. If you had a planet where the nuclear heat that powers tectonics was absent from the start, then there would be no topography to start with. Many scenarios for the beginning of life, and for life’s survival of hard times like possible “snowball Earth” periods, rely on geothermal springs. And without tectonic mixing of the earth’s mantle and crust much of the volatile water and CO2 might never reach the atmosphere… perhaps it would be a frozen dry rock."


And all these wonderful stories because of talking about a pack-raft.

Which reminds me: this friend (who lent me the books) and I made a deal that when there is a warmer weekend - her cut-off point is around 19 degrees Celsius - we will take the rafts down one of Christchurch's rivers and go explore. And then after that there is another friend I'd like to take rafting with me.

I look forward to that!

3 comments:

  1. Tere Maria,
    Leidsin Su read blogimaailmast juba päris tükk aega tagasi. Vahepeal, kui elus oli kiirem aeg, pidasin pausi, aga nüüd olen uuesti aktiivne lugeja ja pean ütlema, et ootan juba kannatamatult Su uusi postitusi!
    No ja olgem ausad, siinne postitus on hea näide sellest miskist, mis mind siia tagasi peibutab. Loodus, prioriteedid, seiklus, oma valikute järgi elamine ... vahvad olete!
    Ja veel, ajasid suure telkimisisu peale ;-) aint et mitte lumes ... brrr, kas töesöna külm ei ole?! :-)
    Jaksu ja pönevust teie kiwi ellu!

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    1. PS. Esimesel ööl, kui magamiskotid on kuivad, ei ole. Teisel ja kolmandal, kui nad on niisked ja pole kuivada saanud, on ;)

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