[meteorite-list] WG: What is "meteorite awareness" and how does it influence fall statistics?

Fri Jun 18 09:35:03 EDT 2004

Dear Mark,

I still think that this awareness (beside market pull and the increase in commercialization) is one important reason for the considerable increase of meteorite recoveries mainly as a result of systematic field search in hot desert areas. 

It started with the systematic meteorite recovery and public relation program conducted by Harvey Nininger back in the 1930s (the average annual count of reported finds jumped from about 5 to about 20 meteorites). When Nininger went off "business" this rate fell back to values around 10 during the 1940s and 1950s and again rised to about 20 in the 1960s when lots of stone were found in the Roosevelt area. Unusual low numbers were reported in the 1990s. The number sharply jumped up in the last 6 year when meteorite were recovered on dry lakes in California and Arizona. 

The case with the other hot desert areas (Sahara and Arabian Peninsula) is much more dramatic: first systematic field searches were conducted back in 1986 by geologists prospecting for oil fields in Libya (they did organized searched during their free time!) These searches yielded about 60 meteorites (named "Daraj" and are actually from "Hammadah al Hamra" area). Between 1989 and 1993 expeditions to Algeria (mainly Acfer and Tanezrouft areas) were organized and yielded 422 meteorites, for the first time including rare and scientific valuable material (e.g. the El Djouf / Acfer shower producing CR2). Due to the tense political situation and civil war in Algeria, focus of the meteorite hunters changed to Libya where more than 1200 meteorites were recovered between 1995 and 2001. In the late 1990s, DaG and HaH fields were already well grazed and it became more and more difficult to find further meteorites in reasonable time. The solution to this problem was Oman, an ideal recovery area. It yielded more than 1000 meteorites to the present date. The problem with the limited time available for systematic field search by professional meteorite hunters was solved with money poured into Morocco as local people started to conduct systematic search, not only in their own country, but also in Western Sahara and Algeria. All these thousands of meteorites finds are know labelled "Northwest Africa".

A bit different is the situation with Antarctica. First systematic expeditions were conducted by a joined US/Japanese field team in 1974 after first meteorites were recovered in the Yamato Mounains back in 1969. Yamato and later the other blue ice fields around the Transantarctic Mountains (e.g. Allan Hills) yielded thousands of meteorites. This all took place long before systematic field search by private hunters began in the hot desert areas (Australia may be an exception here). Even though these Antarctic expeditions were organized by public institutions, "meteorite awareness" and the soaring interest in meteoritics and demand for scientific interesting material was the driving force for the US/ANSMET and Japanese/JARE programs.

Below is a more refined statistics of finds separated by country or find region. 

Jörn
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Joern Koblitz
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REFINED STATISTICS
TOT= total count (falls + finds)
OF: observed falls only
USA: finds from USA
ANT: finds from Antarctica
SAH: finds from Sahara (North African Counties incl. "Sahara" and "Northwest Africa" meteorites)
OMAN: finds from Oman
REST: all other countries

Year  TOT  OF    USA   ANT   SAH   OMAN  REST
1900	17	8	4	0	0	0	5
1901	10	5	4	0	0	0	1
1902	12	7	1	0	0	0	4
1903	21	7	6	0	0	0	8
1904	11	4	0	0	0	0	7
1905	14	5	2	0	0	0	7
1906	13	7	4	0	0	0	2
1907	16	4	6	0	0	0	6
1908	14	7	5	0	0	0	2
1909	11	2	2	0	0	0	7
1910	20	11	1	0	0	0	8
1911	12	5	2	0	0	0	5
1912	12	5	3	1	0	0	3
1913	11	3	4	0	0	0	4
1914	18	7	3	0	0	0	8
1915	11	2	4	0	0	0	5
1916	20	10	3	0	0	0	7
1917	18	9	6	0	0	0	3
1918	15	6	5	0	0	0	4
1919	14	7	4	0	0	0	3
1920	15	5	3	0	0	0	7
1921	17	8	3	0	0	0	6
1922	15	6	5	0	0	0	4
1923	16	6	7	0	0	0	3
1924	18	10	4	0	0	0	4
1925	18	9	2	0	0	0	7
1926	13	7	4	0	0	0	2
1927	17	6	8	0	0	0	3
1928	16	6	6	0	0	0	4
1929	15	7	4	0	0	0	4
1930	20	11	6	0	0	0	3
1931	23	6	5	0	0	0	12
1932	26	8	7	0	0	0	11
1933	30	18	12	0	0	0	0
1934	27	10	15	0	0	0	2
1935	20	6	12	0	0	0	2
1936	34	5	25	0	0	0	4
1937	53	7	35	0	0	0	11
1938	44	11	25	0	0	0	8
1939	33	10	16	0	0	0	7
1940	38	5	31	0	0	0	2
1941	22	4	13	0	0	0	5
1942	20	8	9	0	0	0	3
1943	10	3	4	0	0	0	3
1944	19	7	6	0	0	0	6
1945	9	3	1	0	0	1	4
1946	13	6	2	0	0	0	5
1947	16	5	9	0	0	1	1
1948	22	3	12	0	0	0	7
1949	23	13	5	0	0	0	5
1950	38	12	18	0	0	0	8
1951	19	7	8	0	0	0	4
1952	17	6	5	0	1	1	4
1953	9	3	5	0	0	0	1
1954	20	6	10	0	0	2	2
1955	25	4	12	0	1	0	8
1956	24	8	8	0	0	0	8
1957	18	6	7	0	0	1	4
1958	19	2	4	0	0	4	9
1959	16	6	4	0	0	0	6
1960	30	6	5	0	0	0	19
1961	29	7	14	1	0	0	7
1962	35	8	15	0	0	0	12
1963	32	6	21	0	0	0	5
1964	31	8	12	0	0	0	11
1965	46	4	23	0	0	0	19
1966	27	6	11	0	0	0	10
1967	37	9	13	0	2	0	13
1968	52	4	31	0	1	0	16
1969	70	6	28	9	3	0	24
1970	46	8	19	0	1	0	18
1971	49	7	25	0	0	0	17
1972	31	3	18	0	1	0	9
1973	30	4	5	12	0	0	9
1974	689	7	8	663	0	0	11
1975	315	4	14	287	0	0	10
1976	62	12	17	22	0	0	11
1977	308	9	9	266	0	0	24
1978	384	3	18	353	0	0	10
1979	3.772	2	17	3745	1	0	7
1980	169	6	12	137	0	0	14
1981	489	7	25	447	0	0	10
1982	228	3	8	203	0	0	14
1983	478	5	20	439	1	0	13
1984	388	9	9	359	0	0	11
1985	374	3	10	355	1	0	5
1986	1.448	10	7	1389	17	0	25
1987	1.068	1	2	1022	34	0	9
1988	3.158	6	6	3132	8	0	6
1989	136	5	8	0	103	0	20
1990	1.575	8	7	1359	180	0	21
1991	842	6	5	600	141	0	90
1992	366	3	8	257	51	0	47
1993	957	4	3	888	14	0	48
1994	713	6	7	612	43	0	45
1995	486	6	5	283	183	0	9
1996	560	4	2	387	165	0	2
1997	1.684	3	5	1147	509	0	20
1998	492	10	13	194	265	0	10
1999	1.615	7	25	1075	360	138	10
2000	1.329	5	25	501	446	342	10
2001	939	3	29	203	209	482	13

> -----Ursprüngliche Nachricht-----
> Von: minador [mailto:minador at yahoo.com]
> Gesendet: Freitag, 18. Juni 2004 07:39
> An: Jörn Koblitz; Meteorite-list at meteoritecentral.com
> Betreff: What is "meteorite awareness" and how does it influence fall
> statistics?
> 
> 
> Hi List,
> 
> What is meant by "meteorite awareness"?  I was using it to 
> mean that people
> are familiar with the look, feel, etc. of meteorites.  Until I started
> collecting and handling meteorites, I had a hard time 
> distinguishing them
> from just looking at photos.  And I had a hard time with 
> meteorwrongs.  Now
> that I'm more "meteorite aware", I'm pretty confident in identifying
> chondrites (at least fairly un-weathered ones - irons can 
> still be pretty
> problematic for me).
> 
> That being said, I suppose that increased "meteorite 
> awareness" might not
> have much of an effect on falls or finds.  Regarding falls, I think if
> people witness a fall, they're highly likely to report it 
> even if they don't
> know what meteorites look like (or understand the concept of 
> a meteorite).
> Maybe there would be less false reports.
> 
> Regarding finds, I think the effect of more "meteorite 
> awareness" would be
> less meteorwrongs being sent to labs (over the years my dad 
> and I sent a few
> to ASU).  It wouldn't necessarily be more being found since 
> people tend to
> err on the side of caution and send every strange thing the 
> find to experts.
> 
> Maybe the reason that increased population density doesn't 
> translate into
> more fall observations could be that the increases in 
> population tend to be
> confined to urban areas.  In this instance more witnesses 
> might not have
> much of an effect.  A fall like Park Forest would have probably been
> discovered even if it was a smaller urban area.  There are 
> still huge areas
> that are relatively unpopulated even though there are much more people
> around today.  In fact I believe that since the Great 
> Depression, there is a
> lower population density in rural areas (in the U.S.).  
> People tend to bunch
> up in urban areas, and there are less farmers, logger and 
> ranchers out there
> observing subtle changes that would escape the transient 
> hiker, explorers,
> etc.  I could be quite wrong on this though, so I'd like to 
> hear more.  I'm
> not denying increased urbanization, but considering that the 
> Western U.S is
> ~80% public lands, the private areas being developed do not 
> translate to
> much more "populated land area".
> 
> I don't want to get too far from Tracy's question though.  
> They got a bet on
> the line!
> 
> Have a great night everyone (or day to those in merry old Europe and
> beyond!)
> 
> Mark Bowling
> 
> Jörn wrote:
> 
> ----- Original Message ----- 
> From: "Jörn Koblitz" <koblitz at microfab.de>
> To: <Meteorite-list at meteoritecentral.com>; <markf at ssl.gb.com>
> Sent: Thursday, June 17, 2004 1:59 AM
> Subject: WG: [meteorite-list] Meteorite Fall Rates
> 
> 
> > If 'increasing meteorite awareness' would result in a net
> > increase then
> > why isn't that reflected in the figures?
> 
> I think, that "meteorite awareness" will not really influence the
> statistics. The billions of people, mainly those living in 
> highly populated
> areas with "low meteorite awareness" like China or India do 
> highly influence
> the fall statistics (contrary to the find (NOT observed 
> falls) statistics
> which is highly influenced by meteorite awareness).
> 
> 
> 