Shipwrecks and Carrion Flowers

On Sunday Sila and I and Sandi went down to Cape Point and went for the WORLD'S WINDIEST HIKE. Sorry I didn't bring my camera because we did the Shipwreck Trail in the park. Have you seen Pirates of the Caribbean 3: At World's End? Because there's a scene where Johnny Depp is in this plain of white sand and just his ship sticking out like a big black hulk. That's what Shipwreck Beach looks like, except with lots of parts of ships everywhere. It is brutal. I didn't have my camera on me so here's somebody's picture from the series of tubes:
That's what it looks like (I guess) when it's not blowing 60+ km/hr across the beach, at which point it becomes a surreal stinging wasteland.

To avoid complete and total exfoliation, we walked back to Olifantsbos via the inland trail. We saw lots of droppings as big as moose pellets - but no eland or bontebok from which they must have originated. We picked up some ostrich feathers caught in a prickly bush. There were lots of cute little succulents.

We stopped on the way back at the Good Hope Nursery outside Scarborough which specializes in indigenous plants and picked out four more succulents to complete my box. I don't know what they all are yet! But yesterday I got it all planted up: This is an unknown. The guy at the nursery told me it was Crassula but he didn't know what kind. I looked at a billion on line today and although there are thousands of kinds of Crassula, I didn't see any with little pea leaves like this. More research is necessary. Here's the coolest/ weirdest one: Stapelia grandiflora. It's a dwarf species from the same genus as that giant carrion flower that is polinated by flies and smells like dead stuff and/or trash. Some of the specimens at the nursery had blooms so I smelled it and yah, it smells dead. But the scent is not too strong. So I bought one with two buds on it. The flowers are really weird looking, like a drunk starfish leaning up against the little trunks. So weird and cool.

The box is in my office window now, gets low sun until about 11 every day so I think that will satisfy all these guys. I need to find somebody who can tell me what each really is! Tempting to follow it up with a cactus box on my other window sill... but maybe I should just be patient since I already have 101 tomato plants to take care of.


Garden is growing...

So my first seed trays didn't work. Wrong soil, too much wind? drying sun? cold nights? I have no idea. Sila built shelves in the kitchen and one is high, under the skylight. Its warm there. Also I did some research on the dumptrucks and series of tubes (Stevens, T. 2005) and discovered that a good soaking in tea will help soften seed casings and promote germination. On Sunday we emptied out the old trays and started over. We also bought some basil seedlings because, well, Sila needs pesto. The results:

A mini forest of basil, rapidly outgrowing its trays:

Basil sprouts in 3 days! The seed packet says 8:

Tomato sprouts in 3 days! (see blurry little seed leaves in foreground). Do you think it's my feel-good blue wall that's making the plants so happy? Or the tea?

I have plans for these little guys... in my garden diary

Dad sent me an ad for hanging upside-down tomato pots - I recently bought a gorgeous book called "Crops in Pots" that has some similar ideas - We are going to get wall baskets of coconut fiber and plant the cherry tomatoes out the sides and basil in the top. Pasta baskets!

Now that I have the perfect germination laboratory, I am ready to try my chilis again once I move these things outside. Stay tuned for excessive tomato consumption and hot recipes.

In unrelated news, been busy these last weeks with an XRF class and planning field work for 08 in Namibia and Mozambique. Working on an urgent paper with Francesca and a less urgent one with Emily and Francesca. Tired. Been swimming - this morning 1320m at the Obz community pool. It's just me and the Grammy Faye caps since school went back in session.


Geology in Afrikaans

This morning I went to Stellenbosch to work with Jodie for the day. She was late so I enjoyed looking at all the cool display cases in the geology building. There are lots of things besides minerals, although the mineral collection was impressive! They also have a case of stalactites, ferric nodules, and all kinds of cool things.

I am getting a big kick out of the Afrikaans words for minerals. For example, "kwartz". Here is a sample of dioptase:

Here is a sample of epidote:

Here are some almandine garnets:

And here is some zircon:

This Triassic monster from Beaufort West greets you at the entrance. click to elarge and check out the size of his paws.


Why no emails?

I don't know how the Guardian managed to get this murky scaryland picture of our beautiful city:

because it DOESN'T LOOK ANYTHING LIKE THAT! This is some photoshopper's impression of the apocalypse or something. But yes those are our Simpson's towers. They are small though.

However, the story from which I pulled that picture is correct, we are experiencing "load shedding", strangely reminiscent of the rolling blackouts Californians will remember when some corrupt bastards undertook to ruin everyone else. This is oddly familiar! Hopefully the party will take some fast action to allow self-generators to sell back to the grid. Because every self-respecting business and many of the universities (not us, of course) are generating their own power for the 2-3 hrs in midday when the blackouts roll through.


Malmesbury Group and the SeaPoint Contact

The Geological Society of South Africa, Western Cape Branch held its end-of-year field trip on Saturday 8 Jan. I have been working on this blog post since then but got distracted writing a shorter (less slangy) summary for the GSSA WCB newsletter. So sorry but here it is finally. It was a walk through the Tygerberg terrane of the Malmesbury Group up to the lit-par-lit contact with the Cape Granite at Sea Point, Cape Town. Now don't give up yet, I'll tell you what all that means in a minute. The leaders were Prof. Alex Kisters (structure) from U. Stellenbosch and my dear friend Dr. John Rogers (sedimentology) from good ol' UCT.

Zircon is a great little mineral that grows during igneous or metamorphic heating in rocks, and it takes in all the Uranium. After the hot period ends, the uranium starts to decay, like a little stopwatch in the rock. This makes it possible to date the igneous or metamorphic heating in a rock. If that rock then erodes, dumping sediment into an ocean basin, the zircon's other special feature comes into play - it's darn hard. It survives all that tossing around and when you collect the sediment millions or billions of years later, it's still intact, tiny stopwatch ticking away. Even if the sed has been through another heating event, it's possible to find some of the little grains which didn't reset their clocks. So you can say, the age of the youngest zircon stopwatch in the sediment (or detritus) is an older boundary on the age of the sedimentary deposit. See? cool.

Anyway, the Malmesbury Group is a huge pile of shale-siltstone-sandstone deposited in the latest preCambrian times. It is therefore not fossiliferous in the least, which makes it somewhat more difficult to determine exactly how old it is. Some people have picked detrital zircons out of it that give 3 age groups: 2 billion years, ~1.5 billion years, and 545 million years. This means the part of the Malmesbury where these data were collected was deposited after 545Ma.

John got us started off with an orientation at Three Anchor Bay. John can be counted on for all kinds of maps, rocks, artifacts, old theses, any type of "visual aid" one could possibly wish for on a field trip!

The sedimentary structures came on fast and furious. You would have to hike miles and miles across Kodiak to find a tenth of the good stuff we saw in less that a mile of strolling. Here is a gorgeous bed that I (and Saranne Cessford, thereby earning me some credibility) interpreted as a rip-up bed: that is, a bed of sandstone, minding its own business on the seafloor, got torn up by a mudflow! which ripped it into blocks, later to settle out in the mud.

Mega version of the same: a true Olistostrome! Here full big sandstone beds have been tumbled and broken in a massive mudflow. This one is only about 4m thick but imagine if it were an order of magnitude thicker - that's where it starts getting really complicated to tell if a melange (or mix of rocks) is made by sedimentary processes or tectonic processes. Ask me later why that even matters, it's a whole nother question.

OK now for the real fun: Name That Structure (NTS). We used to play this game as undergrads, when we were first learning structures... Thinking, no doubt, that this was a rookie pursuit and we would soon run out of structures we couldn't identify. WRONG.

Something weird happening here, not immediately obvious. It has to do with bedding-cleavage intersection, but the bedding is not... normal. is it caused by the cleavage? or is the cleavage wrapping around some weird bedding features? Two pictures and then my theories. First outcrop photo: vertical joint surface normal to bedding strike, cleavage is vertical, bedding dips ~50° to your right. Second photo, cleavage barely right-dipping, bedding is left-dipping, and the big limpet is ~2cm long axis.

Theories (and I should say here that initial impressions split quite neatly between sedimentary and structural geologists):
1. Scallopy bedding - these are ripple marks with sand lags into the troughs. Cleavage later wrapped around them.
2. Structural feature - less well defined but since the wavelength is seriously perfectly regular, as well as the amplitude, and these only occur in the fold hinge - maybe they are some kind of disharmonic folding.
3. Rayleigh-Taylor discontinuities, with top planed off by subsequent turbidity currents, overprinted by pressure solution cleavage which intensifies within R-T "intrusions".

Obviously option 3 is all me and I can't blame anybody else for it. However I'm currently 60% for option 1. Opinions? How come nobody comments on my blog? And is it really true that the Japanese geologists have a petrol-rockblade-skillsaw which would be the perfect sampling solution to this kind of problem?

We get closer and closer to the contact with the granites and little dikes (dykes; ZA) seem to emerge everywhere - dikes which are folded with the pressure solution cleavage - serious compression (ductile!) during the granitic intrusion - leaving NO EVIDENCE whatsoever in the absence of active strain markers. Isn't that beautiful?

Here we have John showing Alex's sketch of the contact. The cross section Alex drew is visible to the naked eye in the profile of Lion's head which we could see from the road. Really nice place to see into the rocks. In the foreground you can see my pal Kirsten from Dresden. She runs the new ICPMS (inductively coupled plasma mass spectrometer) at work, that is, unless Eskom randomly shuts off power to random neighborhoods at random times during the day for 2-2.5 hr intervals. Oh wait that's exactly what's going on! It's called "load sharing". Maybe Ken Lay faked his own death and has found a new liberal state to punish with Enron style rolling blackouts! Or maybe not. but I digress...
Now we come to the best part. As you can see in the hillside of Lion's Head, above, we were walking from the black shales toward the edge of a big granite batholith. The contact runs right through Lion's Head and the 403Ma sandstones unconformably overlie it. As we approached the contact there were more and more little granite dikes, then bigger, then we started seeing evidence of macroscopically ductile flow in the black shales as well as the pinkish granites:
The layering is parallel to the contact, as if the granitic magma squeezed its way up hundreds of tiny parallel cracks into the black shales. There is a bit of a metamorphic aureole but really it's only a few 10's meters wide of spotty hornfels - not too hot and not too big. That's a good piece of evidence to suggest that instead of one big giant bubble of hot magma, which would have really cooked the rock around it, the whole body of granites might have arrived slowly over a long period, through tiny cracks. Kind of like ants in my kitchen... one then 10 then 1000...

The big square crystals you see are feldspars that crystallized in the magma chamber at depth and were carried up with the migrating magma. You can see in this photo that some of them seem not to be in the pink granite, but are actually surrounded with black shales. How is that done? Alex gave an explanation based on Norm Sleep's (Stanford) theory using a really elegant fluid pressure model of one of these tiny cracks. Here's Alex with his explanatory sketch, which didn't photograph, so here's my attempt to recreate it:
Anyway all the parallel dikes create an overall gradational contact where there are thicker and more frequent dikes until one crosses the contact and then it's all granite. This is called lit-par-lit or bed-by-bed.

so the question that remains: did the shale melt? or just deform viscously (but very slowly) under high temperature?

There are some conspicuously NOT FLUID looking blocks in there.


Merry Christmas!

** Sila nibbles at my fruitcake when I'm not looking. He doesn't know I know. **

Thanks Mom!


Days in the Life

I've been going back to work this week... Sila surfing when it's alright out there but conditions have been cold, windy and flat. Anyway it's hot in our little yard and the garden is growing. Our tomatoes have grown a lot! and the landlord gave us a lemon tree. Sila put up new clotheslines today in the corner of the patio so they won't decapitate anybody over 5'8" who walks through the yard. Tomorrow he's building new bookshelves. Which brings me to another amazing discovery: Builder's Warehouse in Ysterplat, just out of Cape Town city center en route to our oft-visited Milnerton beach, there is a big box-style home store, just like an OSH or Home Depot or something in the US. We spent 2 hrs there the other day just marveling at how American the whole experience was. Liked it. Missed it. Garden aisle, lighting, showers, flooring, indoor lumber (limited supply + cuts), plumbing, bbq, outdoor furniture.... it was just like the OSH in Marina, California, which I used to shun and avoid, and now relish. Anyway after 2 hours we had a huge cart including palau (?) decking for our new bookshelves which sila is building tomorrow... a terracotta window box for my office, for which I am slowly accumulating a succulent garden of south african plants:
Still building the composition so I can replant them all at the same time.


New Year's Garden

Mom wanted to know the size of our little patio - here's a picture with the view from our front door (our only view!) Sila might be just a smidge sick of having his picture taken.
We went to the beautiful big garden center on Liesbeek Parkway to look for some plants. Sila wanted basil and I wanted tomatoes.
We found gorgeous starts tomato starts (var. Heinz and Floradade) which were so big they were busting out of their pots. Maybe they'll fruit in a few weeks. They had some Habañero starts too, which inspired a whole chili thing. We started some yellow pear cherry tomatoes from seed so when they get big enough we can hang them to grow upside down in 2-L soda bottles. We can hang them on the garden wall.

Inspired by the habañeros, I dug around in the kitchen and cracked some dried chilis for seeds. Planted two trays of Chiles de Arbol which I brought from the Mexican market in California. They are so hot and delicious, I made my own hot sauce in the blender last week with toasted sesame and cloves and allspice and cider vinegar. It is so good! Can't wait to try some of these fresh. Can't wait to get more dried Mexican chilis and try to grow them.
Also planted two trays of birds eye chili seeds that I was saving for Jodie. We bought these on the highway in Mozambique last March. They are crazy hot and Jodie wanted to try growing them so I've been saving seeds. If the starts come up I'll give her some. If not - I still have more chilis. There is no way I would be cooking with the seeds so I can start saving them again!

Here's the back corner of the patio which could be used for a garden but it gets the least sun. Sila is thinking of building a shed roof between the house and the garden wall and shaping surfboards in there. Hmmm. Gotta keep the guy busy some how I suppose. This is much better than the previous plan, which was to build boats in the yard.

Science Debate 2008

A growing list of luminaries, dignitaries, and ordinary folks are pushing for the American presidential candidates to participate in a debate focused on science and technology issues.
At the urging of my acquaintance Andrew, a science journalist who writes for geology.about.com, I have added my name to the list.

There is not a single issue in foreign or domestic policy that doesn't rely heavily on science and technology, not just in obvious ways such as climate change issues, energy, defense, health care and food supply, but also in more subtle but far-ranging ways such as the treatment of evidence, fact, and reason in policy discussions. Many of the candidates have made sweeping statements suggesting that they rely more heavily on doctrine or belief than on scientific evidence, i.e., Huckabee's refusal to recant his 1992 suggestion that AIDS patients be quarantined to prevent transmission of the disease.