Projects: NEO Earth Expeditions
1996 Italy Expedition: Conclusions
August 1996
Many of the samples and much of the data that we collected during the past
two weeks will take months, or perhaps even years, to completely analyze.
Everything we did was carefully documented so that future researchers can
study the material and learn from it.
The accomplishments for the expedition, summarized by team, were as follows:
Stratigraphy
Bed thickness and chromatic information was collected at six sites, two each
near Frontale, Gubbio, and Ancona (a 50 km stretch from southwest to northeast).
All data was copied from field notes to computer spreadsheets. Columnar sections
were plotted by hand showing bed thickness of each layer. Using the K/T layer
as a datum, the team worked on correlating the layers within each pair, and
then across all three pairs. No final conclusions were reached, although there
appeared to be some evidence of the 100,000 year cycle in the data.
Drilling
The team spent seven days in the field. They extracted five cores at Bottaccione,
three small diameter and two large (5 cm) diameter; all were quite fragmented.
At the Contessa site, they obtained one good quality 5 cm core, but failed
to reach the K/T boundary. Finally, at Furlo they obtained a high quality
core that includes the K/T layer.
Photography
About 25 rolls of film were used to take about 600 photos at 10 different
sites. All photos were marked and catalogued, and those that showed clear
stratigraphy were selected out for image processing. With careful analysis
of the images, in conjunction with the data from field stratigraphy, magnetic
susceptibility, and infrared spectroscopy, it is hoped that the late Cretaceous
and early Tertiary timetable can be refined to within 20,000 years.
Image Processing
Approximately 50 photos from 12 sites were scanned at 500 dpi resolution
and archived to removable hard drive media (a total of about 800 megabytes)
for later analysis. Composite columns were created from the photographs taken
at 2 sites and the team looked briefly at cyclicity using NIH software.
Core Processing
Five boxes of core (two from Furlo and three from Petriccio) were cut into
one inch cubes at regular intervals. Nearly 300 cubes were catalogued and
boxed for later analysis for remanent magnetism using sophisticated equipment
not available at Colgigioco.
Peels and Thin Sections
About 100 slides were created from selected samples of the Furlo, Petriccio,
and Gubbio cores. Using the microscopes in the lab at Coldigioco, we saw evidence
in the drastic drop in the size and diversity of the planktonic fauna across
the K/T boundary. In looking for changes unrelated to the K/T crisis, no evidence
of any changes in the fauna was found in the samples from the Cretaceous,
but the rapid evolution in the Tertiary was noted.
K/T Clay Processing
Clay from five sites was washed and mineral grains were separated out. Under
the microscopes in the lab at Colgidioco we found glauconite, sanidine (feldspar
crystals), and flattened iron oxide spherules as well as tiny particles of
shocked quartz and shocked zircon, all most likely ejecta from the impact
at Chicxulub.
Magnetic Susceptibility
The team took readings on 15 boxes of core form Furlo, Petriccio, and Gubbio
representing about 60 meters. Measurements were taken every 2 cm. Data was
graphed and preliminary results show evidence of both minor and major cycles.
The data will be analyzed further by Alessandro Grippo in Los Angeles.
Infrared Spectroscopy
The team scanned 21 boxes of core, and the 25 megabytes of visible and near
infrared and 11 megabytes of infrared data was saved to disk and will be analyzed
later at JPL and Geo Eco Arch Research. Three hours of backup video tape was
also collected. One note of interest: In one box, in a section that appeared
mostly 'dark' across the K/T layer, there was a peak of infrared brightness
just above the boundary. Possible explanations will need to wait for a more
careful analysis of the data.
In the words of Al Fischer, "I can't think of a nicer, more hard working,
more talented group of people than those of you here at Coldigioco. We've
seen a lot of things here that have never before been seen in one place at
one time. Various things look very intriguing. We hope to wring some interesting
results out of the data over the coming months as we perform the analyses.
We have all been on the frontier of Geology these two weeks!"
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