The Oldest Rocks, The Pictures

See Main Post: The Oldest Rocks, so far.

The Nuvvuagittuq Belt on the coast of the Hudson Bay in Northern Quebec.
Credit: Science/AAAShttp://www.livescience.com/environment/080925-oldest-rocks.html

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Richard Carlson, Geochemist, Dept. of Terrestrial Magnetism, Carnegie Institution of Washington

Radioactive elements trapped within zircons provide precise ages, but Dr. Carlson and his collaborators at McGill University and the University of Quebec have not found any zircons in the Quebec bedrock. Instead, they determined the age of the rocks from the amounts of neodymium and samarium, two rare earth elements.

Dr. Carlson said the skeptics might be correct that the bedrock could be younger rocks formed out of older material. “The age is pretty certain,” he said. “The interpretation of the age is less certain.”

If the rocks are as old as claimed, the significance would be that “they’re not dramatically different from rocks you would find today in Japan or places like that,” Dr. Carlson said.

In fact, their chemical signature looks most similar to ocean floor that has been pulled under continents, Dr. Carlson said. That suggests that the process of plate tectonics, reshaping and moving continents, could have already started on the very early earth.

At the very least, the existence of solid rock 4.28 billion years ago would run counter to the traditional image of the young earth as a roiling cauldron of magma oceans, a view that is falling by the wayside among researchers as more geological data is unearthed.

http://www.nytimes.com/2008/09/26/science/26rock.html?hp

 

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Don Francis, McGill Univerity 

 

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Australia’s Zircon Crystals

The bits and pieces of rocks that make up the Jack Hills rock formation are ancient—over 3 billion years old. Individual crystals of zircon within the rocks are 4.4 billion years old, only 150 million years or so younger than the age of the Earth itself. These crystals are the oldest fragments of the Earth yet found. (Photograph copyright Bruce Watson, Rensselaer)

http://earthobservatory.nasa.gov/Study/Zircon/

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May 14 and 15

Blackburnian Warbler, saw, heard
Scarlet Tanager, heard
Chimney Swift, heard
Black and White Warbler?, heard
Rose-breasted Grosbeak, heard
Catbird, heard
Turkey Vulture, flying low over school grounds.
Two Chipping Sparrows mating near chapel entrance.

Early 15th, Cardinal and Robin dominate the sound waves.

May 14, 2008, (up to)

The Robin’s eggs hatched sometime Monday (11th), or earlier.
A dead Black-throated Blue Warbler lay on the ground nearby.
Chimney Swifts heard several days ago.
A woodcock performed this evening.
White-crowned Sparrows sing conspicuously.
Spotted Sandpiper called from the ploughed fields.
An owl? uttered one syllable shrieks a night ago.

Up to Sunday, May 11

Rose-breasted Grosbeaks arrived last Wednesday, I think. First their warbled song, then two appeared at the next door neighbor’s feeder. Warbling birds were noted in the woods nearby. On Sabbath, White-crowned Sparrows showed themselves. They appear a stately sparrow. The churrup of the Oriole was heard as well. Scores of gulls have been counted. Last night, a strange brief gull-like scratchy screech was heard. It called several times. Its very last call seemed different than the others. I listened at my bedroom window for some time, wondering.

Today, Sunday, the wind blows and blows like it is bringing in an enormous storm.

May 7, 2008

This morning – not many noticeable new arrivals. Warblers sing in the distance.
Rain arrives, heavy at times.
Late, after sunset, rain stops. Some migrants heard chirping
as they fly unseen overhead.

Memo: Deer seen a few days ago in Westrate’s back yard.

Robin still sits on nest.
I also suspect a Cardinal’s nest in a neighbor’s front yard.

May 6, 2008

Another clear crisp morning. Heard a warbler singing. Getting rusty on warbler sounds, I guess. An Evening Grosbeak flew and called straight overhead. Blue Jays make their presence known. Do they migrate? Or, spread out somehow.

May 5, 2008

Clear, crisp morning. Wood Thrush. Chickadees. Yesterday, Barn Swallow. Blue Jays.

May 3, 2008

The stormy weather continues to bring in the migrants: Yellow Warbler?, Catbird?, Least Flycatcher, Great Crested Flycatcher (in tree outside the boy’s dorm),

Other birds seen earlier not yet reported:

Horned Lark

Late evening, sunset time, Brown Thrasher calling in clear couplet phrases.

After dark, actually May 3. Woodcock calling from ploughed field area. Killdeer fussing.

 

May 2, 2008

Today, the weather was stormy, windy.
Low flying gray clouds brewing rain.
Apparently, this kind of weather
stirs up the birds. New sitings for Kingsway
includes the Great Blue Heron;
two low-flying very fast of wing ducks;
white-throated sparrow;
ruby-crowned kinglet;
an accipeter, perhaps a Cooper’s,
certainly larger than a Sharp-shinned.

The mother robin still tends to her nest.
I wonder how successful this clutch will be.

May 1, 2008

6:53

A lovely morning. Birds observed today, not on yesterday’s list: Mourning Dove, Redwinged Blackbird, Cowbird, Gold Finch, Starling, Song Sparrow.

Cardinals and Chipping Sparrows continue to be prominent. Yesterday and today, I noted the quick response two, or more, Chipping Sparrows provided each other in their songs.

Gulls seemed more prominent than usual.

The Robin’s nest is abandoned, I think.

A study of Burdock on campus interests me.

Documented the leaf growth of trees, year to year, does as well. The leaves continue to develop in their earliest stages.

The Dogwood blossoms at the SDACC have turned brown, maybe from frost.

The blossoming bushes at the Old Gym are in full bloom still.

This weekend, Alumni weekend. I teach the Sabbath School lesson.