[meteorite-list] exact Carolina Bay crater locations, RB Firestone, A West, et al, two YD reviews, 2008 June, 2009 Nov, also 3 upcoming abstracts: Rich Murray 2009.11.14

Rich Murray rmforall at comcast.net
Sun Nov 15 01:39:04 EST 2009


exact Carolina Bay crater locations, RB Firestone, A West, et al, two YD
reviews, 2008 June, 2009 Nov, also 3 upcoming abstracts: Rich Murray
2009.11.14
http://rmforall.blogspot.com/2009_11_01_archive.htm
Saturday, November 14, 2009
http://groups.yahoo.com/group/astrodeep/message/31
___________________________________________________


http://ie.lbl.gov/mammoth/mammoth.html Firestone paper links

http://ie.lbl.gov/mammoth/TunguskaConferenceA4_Firestone.pdf
37 pages
Firestone, R.B.; West, A.; Revay Zs.; Hagstrum J.T.; Belgya T.;
Que Hee S.S.; and Smith, A.R. (2008)
Analysis of the Younger Dryas Impact Layer,
100 years since Tunguska phenomenon: past, present, and future,
June 26-28, Moscow, in press. 54 references

R.B. Firestone 1,
A. West 2,
Zs. Revay 3,
J. T. Hagstrum 4,
T. Belgya 3,
S.S. Que Hee 5,
and A.R. Smith 1
1 Lawrence Berkeley National Laboratory, Berkeley, Ca 94720,
[ #43 Henderson, G.M.; Hall, B.L.; Smith, A.; & Robinson, L.F.
(2006) Chem. Geol. 226, 298-308 ]
2 GeoScience Consulting, Box 1636, Dewey, Arizona 86327,
3 Institute for Isotope and Surface Chemistry,
P.O. Box 77, H-1525 Budapest, Hungary,
4 U.S. Geological Survey, 345 Middlefield Road MS 937,
Menlo Park, CA 94025,
5 University of California, Los Angeles, ICP-MS Facility,
Los Angeles, CA 90095

Abstract

We have uncovered a thin layer of magnetic grains and
microspherules, carbon spherules, and glass-like carbon at
nine sites across North America, a site in Belgium, and
throughout the rims of 16 Carolina Bays.
It is consistent with the ejecta layer from an impact event and
has been dated to 12.9 ka BP coinciding with the onset of
Younger Dryas (YD) cooling and widespread megafaunal
extinctions in North America.
At many locations the impact layer is directly below a black mat
marking the sudden disappearance of the megafauna and Clovis
people.
The distribution pattern of the Younger Dryas boundary (YDB)
ejecta layer is consistent with an impact near the Great Lakes
that deposited terrestrial-like ejecta near the impact site and
unusual, titanium-rich projectile-like ejecta further away.
High water content associated with the ejecta, up to 28 at.%
hydrogen (H), suggests the impact occurred over the Laurentide
Ice Sheet.
YDB microspherules and magnetic grains are highly enriched in
TiO2.
Magnetic grains from several sites are enriched in iridium (Ir), up
to 117 ppb.
The TiO2/FeO, K/Th, TiO2/Zr, Al2O3/FeO+MgO, CaO/Al2O3,
REE/chondrite, FeO/MnO ratios and SiO2, Na2O, K2O, Cr2O3,
Ni, Co, U, Th and other trace element abundances are inconsistent
with all terrestrial and extraterrestrial (ET) sources except for
KREEP, a lunar igneous rock rich in potassium (K), rare-earth
elements (REE), phosphorus (P), and other incompatible elements
including U and Th.
Normal Fe, Ti, and 238U/235U isotopic abundances were found
in the magnetic grains, but 234U was enriched over equilibrium
values by 50% in Murray Springs and by 130% in Belgium.
40K abundance is enriched by up to 100% in YDB sediments and
Clovis chert artifacts.
Highly vesicular carbon spherules containing nanodiamonds,
glass-like carbon, charcoal and soot found in large quantities in
the YDB layer are consistent with an impact followed by intense
burning.
Four holes in the Great Lakes, some deeper than Death Valley,
are proposed as possible craters produced by the airburst
breakup of a loosely aggregated projectile.

from Table 2:

CLOVIS SITES:
Blackwater Draw, NM----- 34.27564N 103.32633W
Chobot, AB, CAN--------- 52.99521N 114.71773W
Gainey, MI----------------- 42.93978N,, 83.72111W
Murray Springs, AZ --------31.57103N 110.17814W
Wally's Beach, AB--------- 49.34183N 113.15440W
Topper, SC -- T-1--------- 33.00554N,, 81.49001W
Topper, SC -- T-2--------- 33.00545N,, 81.49056W

CLOVIS-AGE SITES:
Daisy Cave, CA----------- 34.04207N 120.32009W
Lake Hind, MB, CAN----- 49.43970N 100.69783W
Lommel, BELGIUM------- 51.23580N,,,,, 5.26403E
Morley drumlin, AB-------- 51.14853N, 114.93546W

CAROLINA BAYS: (with paleosol beneath)
Blackville, SC -- T13------- 33.36120N 81.30440W
Myrtle Beach, SC -- M31-- 33.83776N 78.69565W
Lk Mattamuskeet -- LM---- 35.51865N 76.267917W
Howard Bay, NC -- HB---- 34.81417N 78.84753W
[ http://ie.lbl.gov/mammoth/PP43A_10.pdf ] poster 1.07 MB

CAROLINA BAYS: (no paleosol reached)
Myrtle Beach, SC -- M33-- 33.81883N 78.74181W
Myrtle Beach, SC -- M24-- 33.83118N 78.72379W
Myrtle Beach, SC -- M32-- 33.84034N 78.70906W
Salters Lake, NC -- B14--- 34.70992N 78.62043W
Lumberton, NC -- L33----- 34.75566N 79.10870W
Lumberton, NC -- L28----- 34.77766N 79.05008W
Lumberton, NC -- L31----- 34.78117N 79.04774W
Lumberton, NC -- L32----- 34.79324N 79.01871W
Moore Cty, NC -- MC1--- 35.30104N 78. 84753W
Sewell, NC -- FS3--------- 34.95800N 78.70280W
Lake Phelps -- LP---------- 35.78412N 76.434383W

I looked all these up with Google Earth and Maps.
In many cases, many craters overlap complexly, so it
is not clear which is the one studied.
It is always easy to find many more in each cluster.


http://journalofcosmology.com/Extinction105.html  20 pages
Firestone, R. B., 2009,
The Case for the Younger Dryas Extraterrestrial Impact Event:
Mammoth, Megafauna, and Clovis Extinction, 12,900 Years Ago.
Journal of Cosmology. vol. 2, pp. 256-285. 67 references

Abstract

The onset of >1000 years of Younger Dryas cooling, broad-scale
extinctions, and the disappearance of the Clovis culture in North
America simultaneously occurred 12,900 years ago followed
immediately by the appearance of a carbon-rich black layer at
many locations.
In situ bones of extinct megafauna and Clovis tools occur only
beneath this black layer and not within or above it.
At the base of the black mat at 9 Clovis-age sites in North
America and a site in Belgium numerous extraterrestrial impact
markers were found including magnetic grains highly enriched in
iridium, magnetic microspherules, vesicular carbon spherules
enriched in cubic, hexagonal, and n-type nanodiamonds,
glass-like carbon containing Fullerenes and nanodiamonds,
charcoal, soot, and polycyclic aromatic hydrocarbons.
The same impact markers were found mixed throughout the
sediments of 15 Carolina Bays, elliptical depressions along the
Atlantic coast, whose parallel major axes point towards either
the Great Lakes or Hudson Bay. The magnetic grains and
spherules have an unusual Fe/Ti composition similar to lunar
Procellarum KREEP Terrane and the organic constituents are
enriched in 14C leading to radiocarbon dates often well into
the future.
These characteristics are inconsistent with known meteorites
and suggest that the impact was by a previous unobserved,
possibly extrasolar body.
The concentration of impact markers peaks near the Great Lakes
and their unusually high water content suggests that a 4.6 km-wide
comet fragmented and exploded over the Laurentide Ice Sheet
creating numerous craters that now persist at the bottom of the
Great Lakes.
The coincidence of this impact, the onset of Younger Dryas
cooling, extinction of the megafauna, and the appearance of a
black mat strongly suggests that all these events are directly
related.
These results have unleashed an avalanche of controversy
which I will address in this paper.

Keywords: Younger Dryas, Extinctions, Extraterrestrial Impacts,
Black Mat, Clovis, Mammoth, Megafauna

"West also investigated sediment from 15 Carolina Bays,
elliptical depressions found along the Atlantic coast from
New England to Florida (Eyton and Parkhurst, 1975),
whose parallel major axes point towards either the
Great Lakes or Hudson Bay as seen in Fig. 3.
Similar bays have tentatively been identified in Texas,
New Mexico, Kansas, and Nebraska (Kuzilla, 1988)
although they are far less common in this region.
Their major axes also point towards the Great Lakes.
The formation of the Carolina Bays was originally ascribed
to meteor impacts (Melton and Schriever, 1933) but when
no meteorites were found they were variously ascribed
to marine, eolian, or other terrestrial processes.

West found abundant microspherules, carbon spherules,
glass-like carbon, charcoal, Fullerenes, and soot throughout
the Carolina Bays but not beneath them as shown in Fig. 4.
Outside of the Bays these markers were only found only
in the YDB layer as in other Clovis-age sites."

"Figure 3. The Carolina Bays are >>500,000 elliptical,
shallow lakes, wetlands, and depressions, up to >>10 km long,
with parallel major axes (see inset) pointing toward the
Great Lakes or Hudson Bay.
Similar features found in fewer numbers in the plains states
also point towards the Great Lakes.
These bays were not apparent topographical features
until the advent of aerial photography."

This figure shows nice color LIDAR typographic images
of 8 craters, 0.5 to 4 km wide.
 I used Ctr + in Windows Vista to expand the NA map, counting
18 elliiptical craters in the Great Plains:
Texas 4
New Mexico 3
Colorado 2
Kansas 4
Nebraska 5.

It's not easy to locate the LIDAR craters on the photo images
of Google Maps and Earth, but I've had a lot of practice with
these states and all over Earth this year, including brief visits to
many craters in New Mexico and Kauai.
I managed to find Salt Lake, NM, and Coyote Lake, TX.
The features are often complex enough to make assigning a
size fairly arbitrary.

Nice maps and typo maps and tourist info are available free on:
www.trails.com
www.goingoutside.com

Salt Lake, New Mexico 34.079932 -103.089600,
1.177 km lowest crater elevation, NEE axis, EES rim el 1.215,
N edge el 1.183, ~10x3.7, E from center 7 km to Texas and
18 km to Coyote Lake (another LIDAR image), much white
deposits,  N of Rd 235ew,  just S of Rd 88 S Roosevelt Road 10,
24 km E of 206ns, 26 km EES of Portales, striking "comb" of
many parallel ditches running into lake from E side

Little Salt Lake is 7 km W of center,  el 1.183, 3.6 wide, E comb,
very similar and obviously connected

Coyote Lake, Texas 34.102105 -102.872902 1.162 site N 1.200
15 km SW of Muleshoe, size 5.7x4.3, E comb, W of Rd 214 ns

Baileyboro Lake 34.0045 -102.8206 1.155 site SW 1.186
no comb, size 2

Upper White Lake 33.9426 -102.7678 1.129 site W 1.171
S,E comb, size 1.8,  2 km W of Rd 214ns

just 1 km NE is a double crater, 1.129 site W 1.169,
S,E comb, 1.6x1.3, just W of Rd 214ns

then just N is Muleshoe National Wildlife Refuge, same size,
with a .24 wide flat round dark crater 1.667 site W 1.170

just E across Rt 214ns is Upper Pauls Lake, complex 2 km size,
1.129 site W 1.147

33.860831 -101.449100 1.038 site W 1.125
NNE 15x8, 29 km SSE of craters by Rd 214ns,
10 km W of Rd 385ns, 15 km SW of Littlefield on Rd 84nwse,
comb on whole E side

Returning to New Mexico, Lane Salt Lake, similar to Salt Lake
33.465718 -103.608318 1.265 site 1.300 size 10x4 NE
90 km SW of Salt Lake, E comb

34.038716 -103.350290, el 1.266, site about 1.269, .16 wide,
W of 206ns, just S of S Roosevelt Rd 15, dark

34.026073 -103.399379 1.278 site 1.283 size .76,
extends to SW

34.026338 -103.437950 1.279 site 1.287,
cut by Rd 235ew size 1.5

WSNM 32.755610 -106.413363 1.186 site S 1.210 68x33 km
White Sands National Monument, gypsum sand


Howard Bay, NC -- HB---- 34.81417 -78.84753
[ Wet center marked in blue on Google Maps Terrain,
named Pages Lake .7x.2, with Mines Creek NW to SE
at both ends, but built over on Google Earth,
34.815274 -783014 .030 is lowest point,
just SW of Rd 87,  is 13.7 km W of Marshy Bay,
which is NW of Bladen Lakes State Forest.
site W .044 N .044 E creek .010  S .043 all at 1.3 radius,
Rd 87 cuts NW across NE half, farms completely hide crater,
steep bare brown red rise to NWSE ridge from .030 to .044
from .090 to 1.17 radius must be NE rim.
Many local farm roads provide convenient access
across crater interior. ]

[ http://ie.lbl.gov/mammoth/PP43A_10.pdf ] poster 1.07 MB

R. Kobres 1,
G. A. Howard 2 ( george at restorationsystems.com ),
A.West  3 ,
R. B. Firestone 4,
J. P. Kennett 5,
D. Kimbel 2,
W. Newell 2
1 U. of Georgia, Athens, GA, 30602,
2 Restoration Systems, L.L.C., Raleigh, NC 27604,
3 GeoScience Consulting, Dewey, Arizona 86327,
4 Lawrence Berkeley National Lab Berkeley, CA 94720,
5 Dept. of Earth Sciences, U. of California, Santa Barbara, CA 93106.

B23A-0948
Surface Vertical Exaggeration = 7x
Scale: 250 meters
Bay is 2.6 km long

The Carolina Bays are a group of up to 500,000 lakes and
wetlands stretching from Florida to New Jersey
along the Atlantic Ocean.
They are up to11 km in length and about 15 meters in depth.
The elliptical shapes, overlapping rims (Fig.1, left), and common
orientation towards the Great Lakes region have generated many
hypotheses about how the Bays formed.
Extraterrestrial Impact.
This hypothesis was developed by Melton and Schriever (1933)
and expanded by Prouty, (1934) and Eyton and Parkhurst(1970),
who proposed that a meteorite or comet exploded above the
Great Lakes, producing no primary crater.
The secondary fragments and/orshock wave from that blast
formed rough, shallow craters on the Atlantic Coast, and,
over time, wind and water altered those craters to form the
Carolina Bays.
The Impact Hypothesis accounts fo rthe orientation of Bays,
overlapping raised rims, and the fact  that they do not appear
to be forming today.
However, there are problems:
(a) reported Bay ages vary by tens of thousands of years; and
(b) no one has found impact material in the Bays, such as
shocked quartz or other ET markers.
Wind-and-Water.
This hypothesis was offered in various versions
first by Raisz (1934) and others, whosuggested that wind
created deflation basins or parabolic dunes, which later
filled to become lakes that evolved into Carolina Bays.
Johnson (1942) proposed that springs or groundwater
dissolution of soluble minerals caused subsidence, which formed
water-filled depressions that became the Bays.
Kaczorowski (1976) formulated what has become one of the
prevailing views, suggesting that strong ice-age winds blew
across irregular lakes, generating powerful eddy-currents.
Those currents gradually reshaped the lakes into oriented,
elliptical Carolina Bays, whose long axes were perpendicular
to the prevailing wind direction.
The rims were built from wind-transported sand that
accumulated from the dry lake beds during droughts.
While this overall hypothesis clarifies many Bay features,
it has several key weaknesses.
The theory can not explain:
(a)how wind and water could create up to four layers of
stacked Bays with overlapping Bay rims, as seen in Fig.1; and
(b) why modern severe wind and water action, such as occurs
during hurricanes, does not produce or reshape Bays
on the Coastal Plain today.
Objective:
Because of the above questions, the Bay controversy has
remained unresolved for more than 80 years.
In this investigation, we tested these various hypotheses by
examining Howard Bay, which is located about 2km north of
the town of Duartin, Bladen County, North Carolina.
RESULTS
Nine suites of samples were extracted along the 2.6-km long axis
of Howard Bay using a combination of trenching and coring with
an AMS Soil Core Sampler.
Maximum depths varied from about 2 to10 meters.
ET Markers.
Analysis of the samples reveals an assemblage of abundant
carbon spherules (Fig.2), magneticgrains, microspherules,
glass-like carbon, and iridium, typical of the12.9-ka YDB
impact layer found at many other non-bay sites
across North America.
The impact layer conforms to the bottom of the basin
(dark blue on the core symbols), suggesting that the markers
began to be deposited immediately or soon after the Bay formed.
Fig.3 shows the results from Core #11 near the center of
Howard Bay, where carbon spherules are found from
nearly the surface down to about 7.5 meters deep.
Glass-like carbon abundances (not shown) followed
a similar pattern.
Iridium (15 ppb) was found at the lowest level of the basin.
Silt and Clay.
Trenching shows that theBay is filled with >6m of cross-bedded
eolian sand (Fig.4) with no evidence of lacustrine sedimentation.
As a further test, sediment from Core #11 was analyzed with
Standard ASTM sieves, and the results are shown in Fig.3.
The top1 meter averaged about 14% silt and clay, and from
about 1 to 9 meters, there is 0.3% to 6% silt and clay,
values consistent with eolian deposition.
There is typically less than a few percent of any particles
larger than medium sand.
DISCUSSION
Analysis reveals that, unlike typical, peat-rich Carolina Bays,
Howard Bay essentially lacks peat, diatoms, pollen, and other
organic materials, and it also lacks substantial silt and clay.
That suggests this Bay never held water for a sustained
length of time.
Furthermore, the presence of extensive eolian sand calls
into question prevailing hypotheses
(a) that all Bays were lakes and ponds in the past and that
their shapes were formed by wave action, and
(b) that ground water movement led to subsidence that
formed the Bay.
In addition, the presence of impact markers, including high
concentrations of iridium in a layer just above the basal
sediments of this Bay, supports the impact hypothesis
for Bay formation.
The age of Howard Bay appears consistent with and
not older than the YD impact event;
however, our research did not address the reported anomalous
ages of other Bays, a question which remains unresolved.
REFERENCES
1. Melton, F.A. & Scriever, W. (1933) J. Geol. 41, 52-56.
2. Prouty, W.F. (1952) Bulletin of the GSA, Vol. 63, 167-224..
3. Eyton, J.R. & J.I. Parkhurst (1975)
Dept. of Geography Paper No. 9, U. of Illinois.
4. Raisz, (1934) J. Geol., Vol. 42:839-848
5. Johnson, D.W. (1942) The Origin of the Carolina Bays.
Columbia University Press, New York.
6. Kaczorowski, R.T. (1976) The Carolina Bays:
a comparison with modern oriented lakes,
PhD thesis, University of South Carolina, Columbia.
Base image courtesy of James M. Salmons,
President, GeoDataCorp.,
104 E Horton St., Zebulon, NC 27597,
919-269-5744 www.GeoDataMapping.com ]

[ Fig. 1 is a LIDAR elevation image of Marshy Bay,
Google Maps and Earth give fine natural color view,
resolution .001 km, size 3.3x1.8 km, el .033 km,
4 km E of Cedar Creek Road ns,  Rd 53ns,
30 km E of Hwy 95ns, 40 km SE of Fayetteville,
NW of or part of  Bladen Lakes State Forest,
90 km NW of the coast at Wilmington ]
with Little Singletary Lake [ North Carolina 28399 ]
and Horseshoe Lake
to the lower L and lower R,  all oriented NW. ]


One side in the debate has conceded a major point to their critics,
while presenting more evidence for many other major points.

AGU Fall Meeting 2009
ID# PP31D-1389
Location: Poster Hall (Moscone South)
Time of Presentation: Dec 16 8:00 AM - 12:20 PM

The platinum group metals in Younger Dryas Horizons
are terrestrial
Y. Wu 1; E. Wikes 1; J. Kennett 2; A. West 3; M. Sharma 1
1. Dept of Earth Sciences, Dartmouth College, Hanover, NH
2. Department of Earth Sciences,
University of California, Santa Barbara, CA, USA.
3. GeoScience Consulting, Dewey, AZ, USA.

The Younger Dryas (YD) event, which began 12,900 years ago,
was a period of abrupt and rapid cooling in the
Northern Hemisphere whose primary cause remains unclear.
The prevalent postulated mechanism is a temporary shutdown
of the thermohaline circulation following the breakup of an ice
dam in North America.
Firestone et al. (2007) proposed that the cooling was triggered
by multiple cometary airbursts and/or impacts that engendered
enormous environmental changes and disrupted the thermohaline
circulation.
The evidence in support for this hypothesis is a black layer in
North America and in Europe marking the YD boundary
containing charcoal, soot, carbon spherules and glass-like carbon
suggesting extensive and intense forest fires.
This layer is also enriched in magnetic grains high in iridium,
magnetic microspherules, fullerenes containing extraterrestrial
He-3, and nanodiamonds.
Whereas the nanodiamonds could be produced in an impact or
arrive with the impactor, the cometary burst/impact hypothesis
remains highly controversial as the YD horizon lacks important
impact markers such as craters, breccias, tektites and
shocked minerals.
Firestone et al. (2007) contend that bulk of Ir found at the YD
boundary is associated with magnetic grains.
The key issue is whether this Ir is meteorite derived.
We used Ir and Os concentrations and Os isotopes to
investigate the provenance of the platinum group metals in the
YD horizon.
The bulk sediment samples from a number of North American
YD sites (Blackwater Draw, Murray Springs, Gainey,
Sheriden Cave, and Myrtle Beach) and a site in Europe (Lommel)
do not show any traces of meteorite derived Os and Ir.
The [Os] = 2 to 45 pg/g in these sediments and the 187Os/188Os
ratios are similar to the upper continental crustal values (~1.3),
much higher than those in meteorites (0.13).
Higher [Os] is observed in Blackwater Draw (= 194 pg/g).
However, the Os/Ir ratio in Blackwater Draw is 5
(not 1 as expected for a meteorite) and
187Os/188Os ratio = 1.35, which remains constant above and
below the YD horizon.
Kennett et al. (2009) report 200 ppb of nanodiamonds and
about 4 ppb of Ir in bulk sediments from Murray Springs.
Since chondritic meteorites contain approximately 400 ppm
of presolar nanodiamonds and about 500 ppb of osmium,
simple mixing requires that the YD horizon at Murray Springs
should contain about 250 pg/g of Os.
However, the observed Os concentration of YD horizon at
Murray Springs is only 45 pg/g and the 187Os/188Os ratio is 1.66.
These observations suggest that if there was an impact that
produced the nanodiamonds and dispersed them,
it did not provide Os (and Ir) to the Murray Springs and other
North American sites.
We have so far separated and analyzed magnetic grains from
Gainey and Lommel and find their [Os] and 187Os/188Os
ratios consistent with a terrestrial origin.
The [Os] of microspherules analyzed so far are too low to be
derived from meteorites.
Our analyses therefore do not support an extraterrestrial origin of
the platinum metals in YD horizons from North America and Europe.
Contact Information: Yingzhe Wu, Hanover, New Hampshire, USA 03755


AGU Fall Meeting 2009
ID# PP31D-1392
Location: Poster Hall (Moscone South)
Time of Presentation: Dec 16 8:00 AM - 12:20 PM

Nanodiamonds and Carbon Spherules from Tunguska, the K/T
Boundary, and the Younger Dryas Boundary Layer
J. H. Wittke 1; T. E. Bunch 1; A. West 2; J. Kennett 3;
D. J. Kennett 4; G. A. Howard 5
1. Dept. of Geology, Northern Arizona Univ., Flagstaff, AZ, USA.
2. GeoScience Consulting, Dewey, AZ, USA.
3. Dept. of Earth Science and Marine Science Institute,
Univ. of California, Santa Barbara, CA, USA.
4. Dept. of Anthropology, Univ. of Oregon, Eugene, OR, USA.
5. Restoration Systems, LLC, Raleigh, NC, USA.

More than a dozen markers, including nanodiamonds (NDs) and
carbon spherules (CS), occur in a sedimentary layer marking the
onset of the Younger Dryas (YD) cooling episode at ~12.9 ka.
This boundary layer, called the YDB, has been found at nearly
forty locations across North America, Europe, and Asia,
although not all markers are present at any given site.
Firestone et al. (2007) and Kennett et al. (2008, 2009)
proposed that these markers resulted from a cosmic
impact/airburst and impact-related biomass burning.
Here we report features common to the YDB event, the
Cretaceous-Tertiary (K/T) impact, and the Tunguska airburst
of 1908.
In sediments attributed to each event, we and other
researchers have recovered NDs either inside or closely
associated with CS, which appear to be the high-temperature
by-products of biomass burning.
CS range in diameter from about 500 nanometers to
4 millimeters with a mean of ~100 microns,
and they typically contain NDs, including lonsdaleite
(hexagonal diamonds), in the interior matrix and in the crust.
To date, CS and NDs have been found in the K/T layer
in the United States, Spain, and New Zealand.
Similarly, CS and NDs have been found in the YDB layer
in the United States, Canada, United Kingdom, Belgium,
the Netherlands, Germany, and France.
Thus far, every site examined contains NDs and/or CS in the
K/T and YDB layers; conversely, we have yet to detect CS
associated with NDs in any non-YDB sediments tested.
Five allotropes of NDs have been identified in association with
CS: cubic diamonds, lonsdaleite, n-diamonds, p-diamonds,
and i-carbon, which are differentiated by slight variations
in their crystalline structure.
All allotropes have been identified using scanning electron
microscopy (SEM), high-resolution electron microscopy (HREM),
and transmission electron microscopy (TEM) with confirmation
by selected area diffraction (SAED).
Lonsdaleite is found on Earth only in three instances:
(1) in the laboratory, where it is produced by shock synthesis
under a high-temperature-high-pressure regime
(~1000°C to 1700°C at 15 GPa) or by carbon vapor deposition
(CVD) under a very-high-temperature-low-pressure regime
(~13,000°C at 300 Torr) (Maruyama et al., 1993);
(2) after arrival on Earth inside extraterrestrial material; and
(3) as a result of high-temperature cosmic impact/airbursts.
Lonsdaleite associated with CS has been found in sediments
only at the K/T, the YDB, and Tunguska, consistent with the
hypothesis that all three events have cosmic origins,
although the nature of the impactors may have been different.
Contact Information: James H. Wittke,
Flagstaff, Arizona, USA, 86011-4099


AGU Fall Meeting 2009
ID#  PP33B-08
Location: 2006 (Moscone West)
Time of Presentation: Dec 16 3:04 PM - 3:16 PM

Testing Younger Dryas ET Impact (YDB) Evidence
at Hall's Cave, Texas
T. W. Stafford 1; E. Lundelius 2; J. Kennett 3; D. J. Kennett 4;
A. West 5; W. S. Wolbach 6
1. Stafford Research, Inc., Lafayette, CO, USA.
2. Dept. of Geological Sciences, Univ. of Texas, Austin, TX, USA.
3. Dept. of Earth Science & Marine Science Institute,
Univ. of California, Santa Barbara, CA, USA.
4. Dept. of Anthropology, Univ. of Oregon, Eugene, OR, USA.
5. GeoScience Consulting, Dewey, AZ, USA.
6. Dept. of Chemistry, DePaul Univ., Chicago, IL, USA.

Hall's Cave, Kerrville County Texas, 167 km WSW of Austin,
provides a unique opportunity for testing the presence of a
chronostratigraphic datum (YDB layer) containing rare and
exotic proxies, including nanodiamonds, aciniform soot, and
magnetic spherules, the origins of which remain controversial,
but possibly derive from a cosmic impact ~12,900 CAL BP.
The karst-collapse cave in Cretaceous limestone on the
Edwards Plateau contains ? 3.7 m of stratified clays grading to
clayey silts recording continuous deposition from 16 ka RC yr
to present.
The cave's small catchment area and mode of deposition were
constant, and the stratigraphy is well dated based on 162
AMS 14C dates from individual vertebrate fossils, snails,
charcoal, and sediment chemical fractions.
The cave sequence contains an abundant small animal vertebrate
fossil record, exhibiting biostratigraphic changes, and the timing
of the late Pleistocene megafaunal extinction is consistent with
that elsewhere in North America.
At 151 cm below datum is the extremely sharp, smooth contact
separating lower, dusky red (2.5YR3/2) clays below from
overlying dark reddish brown (5YR3/3) clays (forming a
20-cm-thick dark layer) and dating to 13,000 CAL BP,
at or close to the age of the YDB datum elsewhere.
This appears to be the most distinctive lithologic change of the
deglacial sequence.
Sediments at or within 10 cm of this contact contain the local
extinction of 4 species of bats, the local extinction of the prairie dog
(Cynomys sp.) and perhaps other burrowing mammals in response
to decrease in soil thickness, and the uppermost occurrence of 6
late Pleistocene megafaunal taxa that, although rare in the cave,
do not extend younger than 12.9 ka.
We collected and analyzed sediments at high resolution above
and below the distinct lithologic contact at 151 cm.
The red clays from 151 to 153 cm and immediately preceding the
lithologic contact contain an abundance of nanodiamonds
(5 different allotropes), aciniform soot at 2400 ppm, magnetic
spherules, and carbon spherules, all of which we interpret as
evidence for a unique chronostratigraphic marker (YDB)
in the Western Hemisphere.
Because the age of this horizon is ~ 13,000 CAL BP, we
interpret the age of the event as the beginning of the
Younger Dryas cooling.
Regional soil erosion began ~15,000 CAL BP and continued
until 7000 CAL BP, but dating suggests that there is no
discontinuity or hiatus in deposition, and thus, the exotic materials
in that layer are not considered to be erosional accumulations.
Future analyses include sub-centimeter sampling over the
YD boundary, quantification of nanodiamonds and other
event-proxies within 1000 yr of the boundary and in sediments
several 1000 years older and younger, continued refinement of
the AMS 14C record to determine within 50 yr the location of
12,900 CAL BP datum and high resolution analysis
of small animal biostratigraphy.
Contact Information: Thomas W. Stafford,
Lafayette, Colorado 80026

[ 30.135347 -99.537902 M. Jennifer Cooke et al, 2003 Oct,
study of Hall's Cave, 4 p ]
www.geo.utexas.edu/faculty/banner/Publications/Halls_Cave_Geology_03.pdf


For most of these craters, white minerals are striking.
Analysis of elements and isotopes should prove any evidence
of ET origin, and indicate temperatures and pressures
of deposition onto target rocks from steam explosions
of  ice comet fragments.

The shared level of minimal erosion indicates
a shared early Holocene origin.

Amateurs should be encouraged to contribute observations
and samples.

Scientists can organize a center for analyzing samples at a
modest profit, while freely sharing data and research.

Websites, online journals, videos, magazines, books, and
movies can generate reasonable profits in the service of science.

The emerging insights into a past universal truama will lead
to a  increased shared sense of community in our human family.

It is necessary to assess any future risks.

nanodiamond evidence for 12,900 BP Clovis extinction impact,
Santa Rosa Island, discussion on Scientific American website,
Carolina Bay type craters east of Las Vegas, NM:
Rich Murray 2009.09.15
http://rmforall.blogspot.com/2009_06_01_archive.htm
Friday, July 24, 2009
http://groups.yahoo.com/group/AstroDeep/28

widespread Carolina Bay type craters from Clovis comet
12,900 Ya BP? -- 0.7 M long NS crater with fractured
red sandstone on SW rim, CR C 53A, 20 miles E of
Las Vegas, NM: Rich Murray 2009.06.08
http://rmforall.blogspot.com/2009_06_01_archive.htm
Monday, June 8, 2009
http://groups.yahoo.com/group/AstroDeep/27

For Google Earth, here are the Windows/Linux keyboard
commands that make it easy to "fly" easily,
creating an intuitive 3D grasp of the landscape -- my laptop
runs at 1 GHZ with a graphics card, Windows Vista, Chrome,
and 3 GB RAM:

Full screen mode: F11
Lat/Long grid: Ctrl L
Slow movement down: add Alt before other keys
Zoom in, out: PgUp, PgDn keys
Move left, right, forward, back: arrow keys
Tilt view up, down: Shift down arrow, up arrow
Rotate view in circle clockwise, counterclockwise:
Shift right arrow, left arrow
Tilt up towards horizon, down towards directly below:
Shift down arrow, up arrow
Stop, start movement: space bar
Look in any direction: Ctrl, left mouse button and drag
New placemark: Ctrl Shift P
To delete or rewrite a placemark title,
right click it and select Properties.
Reset view to north as forward:  n
Reset tilt to top-down view: u
Select Tools to select Web to return to your other screens.

It's easy to look down about 45 degrees while moving straight
ahead in any direction at an eye elevation of 1-200 km,
scanning a straight strip half-way around the world,
stopping to placemark, examine, and measure any features.

http://worldwind.arc.nasa.gov/java/

Requirements: a 3D video card with updated drivers is necessary.
World Wind has been tested on Nvidia, ATI/AMD, and Intel
platforms using Windows, MacOS 10.4, and Fedora Core 6.

WW gives exact altitudes and ocean depths.
WW images omit human features and give good resolution
from above 30 km.

http://worldwind.arc.nasa.gov/graphics/keychart.jpg

Keyboard controls:
Pan: arrow keys
Rotate LR: A,D keys
Tilt forward down, back up: W,S keys
Zoom down, up: 7 or Home, 1 or End
Stop: space bar or 5.
Position info: F10
Crosshairs: F9
Boundaries: F5
Placenames: F6
Lat/Long Lines: F7
Planet Axis: F8
Dynamic Layers: F1
_____________________________________________________


Rich Murray, MA
Boston University Graduate School 1967 psychology,
BS MIT 1964, history and physics,
1943 Otowi Road, Santa Fe, New Mexico 87505
505-501-2298  rmforall at comcast.net

http://groups.yahoo.com/group/AstroDeep/messages

http://RMForAll.blogspot.com new primary archive

http://groups.yahoo.com/group/aspartameNM/messages
group with 142 members, 1,588 posts in a public archive

http://groups.yahoo.com/group/aspartame/messages
group with 1204 members, 23,955 posts in a public archive

http://groups.yahoo.com/group/rmforall/messages

participant, Santa Fe Complex www.sfcomplex.org
_____________________________________________________




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