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I managed to get Windowmaker up and running on Cygwin, under Window 98.

Check it out.

I just had to comment out one line of code and change my username so that it didn't have any spaces in it. It might not have all the bells and whistles of KDE or Gnome, but at least it takes up less memory. Probably faster, too.

-- juju

A POSSIBLE HOLOCENE IMPACT STRUCTURE IN THE AL 'AMARAH MARSHES, NEAR THE TIGRIS-EUPHRATES CONFLUENCE, SOUTHERN IRAQ.

S. Master
Impact Cratering Research Group, Dept. Geology, Univ. Witwatersrand P. Bag 3, WITS 2050, Johannesburg, South Africa.

A ~3.4 km-diameter near-circular, slightly polygonal, structure is found in the Al 'Amarah marshes, at 474'44.4"E, 318'58.2"N, ~17 km NW of the Tigris-Euphrates confluence, in southern Iraq. Prior to the militarily-inspired draining of the marshes in 1993 [1], the structure was filled with a lake enclosed by an elevated rim, surrounded by a ~500 m-wide dark annulus. After the partial draining of the marshes, the lake has shrunk, and it now appears as a light coloured spot, due to salt encrustations following evaporation of the surface waters.

Geological setting
The alluvial plains of Iraq occupy a structural trough related to active orogenic processes in the Zagros mountains [2]. Near the Tigris-Euphrates confluence, marine sediments of the Miocene-Pleistocene Dibdibba Fm [2] and Holocene Hammar Fm [3] are overlain by Recent delta plain and delta front deposits of the Mesopotamian Plains, in which there are numerous marshes and permanent lakes [2]. The Recent sediments of the Tigris-Euphrates plains were deposited in the last 5000 years, during which 130-150 km of seaward progradation has taken place [2].

Formation of the Al Amarah structure
The strikingly circular shape of the Al 'Amarah structure, contrasts markedly with the highly irregular shapes of the other marsh lakes in the region. Because of the extremely young nature of the sediments in the marshlands, an origin of the structure by karst solution, salt doming, tectonic deformation or igneous intrusion can be ruled out. The structure predates the Iraq-Iran and Gulf wars of the 1980's to 1991, since it is present on satellite imagery from 1984. It is postulated that the structure was formed by a Recent bolide impact in the marshlands of southern Iraq, thus accounting for its geometry, and the apparent rim and annulus visible in pre-1993 imagery.

Quasi-historical reference?
The formation of such a young impact structure may have had a catastrophic effect on the people living in the region, and there is a possible quasi-historical reference to such an event in the account of the Deluge from the Epic of Gilgamesh, dating from ~2000 BC: "...and the seven judges of hell, the Annunaki, raised their torches, lighting the land with their livid flame. A stupor of despair went up to heaven when the god of the storm turned daylight into darkness, when he smashed the land like a cup. One whole day the tempest raged, gathering fury as it went, it poured over the people like the tides of battle." [4] Could this be a reference to a bolide impact which triggerred a tsunami?

References:
[1] North, A. (1993). The Middle East, London, No. 227, Oct. 1993, 22-23.
[2] Larsen, C. E. and Evans, G. (1978). In: Brice, W. C. (Ed.), The Environmental History of the Near and Middle East Since the Last Ice Age. Academic Press, London, 227-244.
[3] Hudson, R. G. S. et al. (1957). Geol. Mag., 94, 395-398.
[4] Sandars, N. K. (1960). The Epic of Gilgamesh. Penguin Books, Harmondsworth, 128 pp.

There are tons and tons of FREE DATA out there for you to grab and peruse. One caveat, most data will be proprietary formats, such as ARC export, ARC shapefiles, ERDAS, and others. SDTS (spatial data transfer standard) is "open" but a pain in the neck to use. I note with glee that FreeGIS has conversion tools for all these formats.

Some places to start your search for FREE GEO DATA, places that I found very handy:

• Starting the Hunt
• USGS Geospatial Data Clearinghouse
• GIS Data Depot
• Global Topographic Data
• EROS Data Center - satellite/remote sensing data
• Earth Explorer

This is in my mind some really really sexy code.
I guess you can call is OSS, you see it in almost every Programming Language book that uses scheme or something like scheme/lisp.... to see what it does check out Y-Combinator Derivation . So the basic idea is to be able to have a recursive func. that does not have a name.....

(define Y
(lambda (m)
((lambda (f) (m (lambda (a) ((f f) a))))
(lambda (f) (m (lambda (a) ((f f) a)))))))

here

ftp://linux.engr.uark.e du/ pub/linux/redhat/redhat-7.0/iso/

john

Trailer A
Trailer B



john

Trailer A
Trailer B



john

it took me a bit to get it so here is another mirror:

http://bell-2216.cheg.uark.edu/ ~jmh3/stuff/timesq.ram

john


john

Gallium arsenide? I don't think so.. maybe something like indium phosphide.

There was an interesting piece recently on sciencedaily about some research being done on electro-optical effects in photo-reactive crystals.

If you like that link, Salamo has a (very brief) page describing some of his other work as well.

Although I'm no expert on the subject and all real questions should be asked of Dr. Kral himself, I do have a passing familiarity with his experiments after certain lectures he gave in my micro class (I attend the University of Arkansas and had him for class this past year).

He is really not trying to say anything special about this experiment; his happens to be a field which excites the imagination and draws popular attention. As such, I think that many of the quotes he has are the result of a request to speculate...

Anyway, his experiment was simply to grow microorganisms in a fairly hostile environment which approximates many of the things that we know about current conditions on Mars. He used volcanic ash which is believed to resemble Martian soil. No temperature or pressure differences were attempted in the first run because little is known about below Mars below the surface. Indeed, the surface is too cold for liquid water (apparently around -200C) and higher temperatures must be assumed if life (as we currently understand it) currently exists on Mars. There are plans for a range of growth conditions which include harsher temperatures and pressures (as far as I know, no one has been able to grow microbes in the experimental conditions, let alone less hospitable ones).

As far as radiation goes, both ionizing and non-ionizing forms are incident on the surface of Mars. However, at subsurface depths there is little reason to think that the intensities will remain the same, especially for non-ionizing (such as UV) forms. Since this is the environment which is to be modeled, radiation was ignored.

Questions about nitrogen appear to stem from a misunderstanding, perhaps, of the metabolism of Archaebacteria. These bacteria are believed by many to be ancestral to the more accessible bacteria which abound on earth and in textbooks. Methanogens, from a very basic understanding that I have, can use a variety of molecules to provide the reducing power necessary to produce biologically accessible forms of energy and, as a result, biologically useful molecules. I know
that NO3 is used but am less sure about pure nitrogen. I am not sure that the researchers themselves know the specific nitrogen source the microbes utilized, but it is believed that the nitrogen content of the experimental medium was ~1%, less than the 3% believed to be present in the Martian atmosphere. In any event, the microbes do not tolerate oxygen (it forms radicals which the cell cannot handle) and it is thought that, esp. given the low level of atmospheric oxygen, subsurface levels of O2 would be conducive to cell growth.

Finally, as to previous proof of life on Mars (esp. the ALH001 meteorite), recent research has cast doubt on Zare, et. al's hypotheses. In fact, this past year Dr. Kral coauthored a paper which suggested that similar chemical patterns could be identified on rocks taken from the moon. Because the moon is such an unlikely candidate for life, the meteorite evidence shouldn't stand on its own as proof of life anywhere.

This all just goes to say that no one will really know anything for certain about life on Mars until some redneck terraformer comes down with a cold...

Sources for this post come from the university press release:

http://PIGTRAIL.UARK.EDU/NEWS/june99/ mars_life.html

Sears D. W. G. and Kral T. A. (1998) Martian "microfossils" in lunar meteorites? Meteoritics and Planetary Science 33, 791-794,

and correspondence with members of the research group. All information presented herein represent the (somewhat poor) understanding of an
unrelated party (me!) and do not represent the actual researchers' beliefs or opinions.

Invicta{HOG}