Impact Database

v. 2010.1

Introduction

History and current status

Data

Impact geology primer

How to contribute

Credits



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:

  1. Download the Impact Database in Google Earth and check that the site you want to report is not included in the database yet.

  2. 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

  3. Consult various maps on the Internet (e.g. Google maps or Google Earth) to confirm that your site is not a

    1. man made feature (e.g. open mine pit, waste dump, construction site, circular field, cattle pond etc.)

    2. well known named natural feature such as volcanic vent, karst feature etc. often part of a natural park.

  4. 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

  5. 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.

  6. 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:

    1. latitude and longitude in decimal degrees (e.g., +29.568791 or -5.1234) NOT in degrees, minutes and seconds.

    2. diameter in km

    3. 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.

  7. 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.