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Introduction
History
and current status
Data
Impact
geology primer
How
to contribute
Credits
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Contributions
of new suspected impact site, comments or corrections of errors
in the database are much appreciated. To make this an efficient
process please follow these steps:
Download
the Impact Database in Google Earth and check that the site you
want to report is not included in the database yet.
If
you are not experienced in the field of impact geology please
first read
French B. M. (1998) Traces
of catastrophe: A handbook of shock-metamorphic effects in
terrestrial meteorite impact structures.
LPI Contribution No. 954. Houston, Texas, USA: Lunar and
Planetary Institute. 120 p.
http://www.lpi.usra.edu/publications/books/CB-954/CB-954.pdf
Consult
various maps on the Internet (e.g. Google maps or Google Earth)
to confirm that your site is not a
man
made feature (e.g. open mine pit, waste dump, construction
site, circular field, cattle pond etc.)
well
known named natural feature such as volcanic vent, karst
feature etc. often part of a natural park.
Do
not get hung up on a single idea of an impact. Human mind sees
what it wants to see. Once you start looking for patterns
(being it circles or triangles) you will see circles and
triangles everywhere. This article illustrates the issue
nicely:
Bond C. E., Gibbs A. D., Shipton Z. K. and Jones S.
(2007) What do you think this is? "Conceptual uncertainty"
in geoscience interpretation. GSA
Today 17(11):4-10.
http://dx.doi.org/10.1130%2FGSAT01711A.1
Impact
structures are rare and most of the circular features on
the Earth have non-impact origin. Do not fix your mind
on the question: “Is this an impact crater?”
Instead, ask: “What is this feature?” Finding all
the possible answers and ruling out one by one is an
exciting endeavor. Just like figuring out a crime scene - would
you first suspect your president just because he/she is a
popular figure? Look for geologic context. For example,
volcanoes usually appear in clusters, sinkholes and volcanoes
often line up along faults, tectonic folds often form circular,
elliptic or wavy patterns at the surface. You may want to read
more on basic geology. Does your structure fit any of these
patterns? Then it most likely is not of impact origin. Contrary
to popular believe, there are only one or two established
trails of impact craters on the Moon and none on the Earth;
consistent with theoretical considerations.
After
you have considered all the points above, send the results of
your investigation to drajmon@yahoo.com
– ideally in the spreadsheet and format of this database.
Even if you reject impact origin for you structure, send it in.
Include:
latitude
and longitude in decimal degrees (e.g., +29.568791 or
-5.1234) NOT in degrees, minutes and seconds.
diameter
in km
other
information such as links to on-line material, your
observations and interpretations etc. Please do NOT send
screen captures of satellite images from Google Earth or other
internet map applications or files freely available on
internet they just fill up my mail box.
Names
and Credits: The database follows the naming and referencing
style common in the scientific literature. Names of the
structures are derived from nearby geographic features.
Personal names should be avoided.
Whoever contributes to
data entry will be named in the database. The author of the
database decides the order of the names and who will be listed
based on the amount of contribution. Consequently, if the notes
for a particular structure are completely rewritten the
previous contributors may be dropped of the list. Throwing an
abstract or coordinates at the database author does not
constitute a contribution recognized in the “Compiled by”
field as the author still has to do most of the work.
The
notes contain standard references to published literature and
personal communication. References to peer-reviewed work are
strongly preferred over personal communication and other
non-peer-reviewed sources and will replace them eventually.
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