১৫ অক্টোবর, ২০১৬

Rock corner.

P1110901

Photographed yesterday, at Parfrey's Glen.

I like the way it looks like a cake with a slice cut out, complete with a layer of filling. How did that layer of broken-up rock get in there?

৫৬টি মন্তব্য:

Expat(ish) বলেছেন...

Eighth grade Earth Science (1st year in the schools!) says glaciation.

-XC

Laslo Spatula বলেছেন...

Made me think of this.

Thiebaud Cakes with missing piece.

There was a painting in particular that I was looking for, but Google let me down.

I am Laslo.

Ann Althouse বলেছেন...

@Expat

This is in the driftless region... that means the last glacier didn't get this far. Don't know enough to comment on earlier glaciers

From the State Park website: "The Glen’s walls are sandstone embedded with pebbles and boulders of quartzite. This quartzite is conglomerate, sometimes called a “plum pudding” stone. The sandstone layers represent ancient sandy beach."

Will Cate বলেছেন...

Love this picture, the awesome sense of time it conveys

Original Mike বলেছেন...

"How did that layer of broken-up rock get in there?"

It's a conglomerate bed; cobbles on an ocean beach that was at this location* when they were laid down 500 million years ago. The cobbles were eroded off of the Baraboo Hills, which were islands in a Cambrian sea. The sea level then rose and buried them with marine sediment which covered the entire range before that was eroded away in more "recent" time, re-exposing the hills and the beach that used to be here.

*Of course, "this location" was on the equator at the time.

Original Mike বলেছেন...

"This is in the driftless region... that means the last glacier didn't get this far."

The glacier did make it that far. It deposited the moraine at the south end of Devil's Lake, forcing the Wisconsin River into its current course around the east end of the Hills.

David বলেছেন...

Nice explanation Mike.

I do hope we can get a handle on this climate change thing. We should not destroy the planet. It's perfectly capable of destroying itself.

Original Mike বলেছেন...

David, I believe that contemplating settings like this puts we puny humans in perspective. We are not destroying the planet.

Original Mike বলেছেন...

I do love the Baraboo Hills. A LOT of geology "happened" here.

Have Althouse and Meade visited the sea stacks at Hemlock Draw yet? They were formed on the same beach that the Parfey's Glen conglomerate bed was laid down upon.

garage mahal বলেছেন...

I went looking for Cerulean Warblers at Parfrey's a few weeks ago. I didn't find any, but I did find this Palm Warbler at the entrance.

Original Mike বলেছেন...

Hey garage.

garage mahal বলেছেন...

Hey.

Original Mike বলেছেন...

I'm guessing, but without inspecting it I'd say the corner is due to a fault.

Expat(ish) বলেছেন...

@althouse, sorry, thought we were of an age. The explanation for *everything* in 1976 "Earth Science" was glaciation.

There was even a wacky "theory" bout continental drift as the book was originally written in 1974. We read (IIRC) a national geography mag about the "stunning new geology" to enhance the discussion.

-XC

PS- Looks like a cool park, we don't have anything with terrain down here in SWF.

Bad Lieutenant বলেছেন...

Hey garage! Despite the inevitable Lovecraftian horror of your inevitable political mispostings, welcome back. Seen any good dogs lately?

Ann Althouse বলেছেন...

Oh, it's an in joke!

But I can't remember any earth science from high school. I never even heard of plate techtonics until after college, and I had absolutely no science in college, unless you count anthropology and sociology, which I remember nothing of. It's pretty much as if I did not go to college.

Ann Althouse বলেছেন...

@garage Really enjoyed yor bird pic! Nice color and focus.

Hagar বলেছেন...

Those rocks all look to be recently fractured; they did not lie in water for long.
Volcanic eruption?

Original Mike বলেছেন...

@Hagar - no volcanoes at the site for a very long time (though the basement rock is igneous). The Baraboo quartzite is very hard and resistant to wear, though most of them look pretty rounded to me. Several have had their exposed faces cleaved off in historical time, which may be what you're noticing.

Hagar বলেছেন...

Or buried volcanic debris exposed and carried downstream by a flood caused by a freak rainfall or an ice dam breaking or something of that kind..

garage mahal বলেছেন...

@garage Really enjoyed yor bird pic! Nice color and focus.

Thanks. I enjoy it. Sure beats politics.

Earnest Prole বলেছেন...

Driftless is one of those cool-sounding words

Meade বলেছেন...

"Have Althouse and Meade visited the sea stacks at Hemlock Draw yet? "

We might make it over there next weekend. I think you recommended it to us in a comment you wrote last May and it's still on our list. Thanks for the reminder.

Meade বলেছেন...

After Mrs. Meade's retirement kicks in, we very well might both go back to college (to get more knowledge).

Original Mike বলেছেন...

"Knowledge is good."

I haven't availed myself to auditing classes yet (though I only turned 60 eleven months ago). Looking forward to it very much.

Original Mike বলেছেন...

Meade - The sea stacks aren't obvious. Until you see them; then they are.

Howard বলেছেন...

The pie slice is not due to faulting as there is no displacement of the puddingstone layer across the apex of the slice. It's simple rock mechanics, compression fractures develop at about a 60-degree angle.

Howard বলেছেন...

A field geology course would be great, then you would have new things to look at on all of your favorite, well worn hikes. Of course, the best place for that is California with the great exposure, rocks of all type, rocks of all ages and stunning displays of active tectonics and Pleistocene glaciation.

UCSB Department Field Trips

Howard বলেছেন...

An easy way to start
Roadside-Geology-Wisconsin

Jupiter বলেছেন...

"I never even heard of plate techtonics until after college, and I had absolutely no science in college, unless you count anthropology and sociology,"

I don't.

rhhardin বলেছেন...

There's a NY contest and an IA contest and a SD contest today. I've worked 25 NY, 4 IA and no SD. Perhaps the SDs are indoors fracking or something.

The 25th NY was a woman, Anne. That makes 3 women I've worked, Sandra in TX, Connie in OK and Anne in NY. All with proficient fists. They're just rare, is all. My electronic log shows 675 contacts, presumably the rest being male.

Yet no upper body strength is required.

It's almost as if interests differed.

Michael বলেছেন...

Garage!!

Hat's off for identifying the passeriformes. I tried and tried but gave up and focused on bigger birds. Any birder understands how important it was for Audubon to shoot them to keep them still to identify and paint.

Best

Michael

garage mahal বলেছেন...

Hat's off for identifying the passeriformes. I tried and tried but gave up and focused on bigger birds. Any birder understands how important it was for Audubon to shoot them to keep them still to identify and paint.

So many migrants moving through right now, it can be hard to identify the fall plumage/first of year warblers and sparrows. And of course the flycatchers :/

Here is a Eastern Phoebe

Freeman Hunt বলেছেন...

"After Mrs. Meade's retirement kicks in, we very well might both go back to college (to get more knowledge)."

Two local friends in their early sixties have recently gone back to school. It's free! Fantastic deal.

rhhardin বলেছেন...

Also, after sunset, worked 3 Germans, in a Germany contest. Once the E layer ionization falls off, you start getting multiple earth bounces on 40m.

You need contests, if you're very low powered, so the other guy has an incentive to pull you out of the noise. He gets points he wants for a little work. Otherwise it's just rude being low powered and expecting him to work at copying you.

rhhardin বলেছেন...

So for retirement I'm doing what I did when I was 12.

rhhardin বলেছেন...

Still there's no email reply from Catherine Malabou concerning her reading of Levinas. I see from google that she's a very important person, even with lectures on youtube on post gender theory and the post feminine, which appears to be on Derrida's excellent _Spurs_. An essay which angered Derrida's first translator Gayatri Spivak. We'll have to see how she does with it.

I think in any case she's an even more serious person than Althouse.

Nevertheless she misread Levinas.

I do recommend _Spurs_, very readable and amusing, on woman.

Original Mike বলেছেন...

"Once the E layer ionization falls off, you start getting multiple earth bounces on 40m."

How many bounces can you hope to get?

rhhardin বলেছেন...

I've gotten 10,000 miles, Rodriguez Island in the Indian Ocean about a thousand miles east of Madagascar; and Australia a couple of times. I don't know how many bounces that is. I assume it's bouncing off the F layer, so it's about 3000 miles a bounce, or 3 to 4 bounces.

Such distances today are unremarkable except for the very low power involved on my end, which makes it astounding, to me anyway.

Today means both sides having good receivers with low internal noise and great filters.

rhhardin বলেছেন...

That is, I'm pleased but not surprised to sometimes hear very distant stations on 40m; but astounded that they can hear me.

Original Mike বলেছেন...

What power are you transmitting?

Original Mike বলেছেন...

What cut the actual glen? The stream now at the bottom of the glen is far too small to have done it. From Dott, Jr & Atting (Roadside Geology of Wisconsin): "We believe that it was cut largely by meltwater from the glacier as it receded eastward from Devils Lake. Souvenirs of the downcutting are visible high on the east wall at the upper, narrowest point where there are two large concave, cylindrical scourings into the sandstone. These are partially preserved potholes bored into the rock as the gorge was deepened. After the ice front eastward past Parfey's Glen, downcutting practically ceased, and since that time, the creek has been fed by a small spring located above the glen."

Bad Lieutenant বলেছেন...

OM, he is always talking about 5W.

Original Mike বলেছেন...

Talking to Australia with 5 Watts? Wow.

rhhardin বলেছেন...

15 watts now, having wired in power from a battery in the basement.

Bad Lieutenant বলেছেন...

Still, good going. Is that voice or Morse?

rhhardin বলেছেন...

Morse only.

It gets through anything.

The trick, since it's much, much better than what I remember as a kid, is probably the good antenna, in this case a full quarter wave vertical with raised (10' high) tuned radials, and no nearby obstacles.

Someday I'll raise it all another 20' but thought I'd wait and see if this one falls down for some reason.

One advantage of raised radials is that you can walk under them, say for mowing the yard, and they're sort of out of sight.

PWS বলেছেন...

I think I'm going to stop reading the political posts and just read all the others. This is more interesting and no kooky comments, etc.

নামহীন বলেছেন...

We ran a circuit from Thailand to Japan, with another station on Okinawa. 32 foot whip. When the freqs cooperated, could use low power of 100 watts. Otherwise, was high power of 1000 watts. Basically 1950's technology deployed in the 1960's. We had to run 24 hours a day.

rhhardin বলেছেন...

I rely on conditions being right; for instance this morning there was no sign of anything very distant. When everything lines up right, you get rewarded. Once or twice a month, maybe.

The size of the antenna isn't the determining thing but what it is at your frequency. 33' is resonant at my frequency, so that's what works best. Longer or shorter would make it worse.

Resonance takes the wasted evanescent field and dumps it back into radiated power.

rhhardin বলেছেন...

I haven't been able to work Japan, and on rare good days can barely hear them so they'd never hear me; It might be the huge tree in that direction that's responsible. Or it might be that there's no good dark path. Sunlight kills 40m signals.

Original Mike বলেছেন...

"I rely on conditions being right; for instance this morning there was no sign of anything very distant. When everything lines up right, you get rewarded. Once or twice a month, maybe."

Sounds like my astronomy.

rhhardin বলেছেন...

A quick shell script reports that I'm missing only four states, no effort to get them all having been made: AK ND UT WY.

RonF বলেছেন...

I've managed to get all 50 states, but it took 3 years off and on. Pretty much all on 40M, with some 20M, and a few of them on 40M PSK-31 instead of SSB.

rhhardin বলেছেন...

As a kid I don't think I ever did all 50, which was many years of operating with much higher power, though I don't remember checking either. I was more into counting countries to see if I had a hundred yet, and ignored states. That was mostly 20m.

rhhardin বলেছেন...

The two chief differences today are

1. Spectacular improvements in receivers, in particular filters, so anything can be isolated in any kind of crowd;

2. Internet advertised contests, so you often work at about ten seconds a contact, leading to an enormous number of contacts, and hence e.g. states, in no time at all. That compresses the years a lot.