Science Frontiers
The Unusual & Unexplained

Strange Science * Bizarre Biophysics * Anomalous astronomy
From the pages of the World's Scientific Journals

Archaeology Astronomy Biology Geology Geophysics Mathematics Psychology Physics

About Science Frontiers

Science Frontiers is the bimonthly newsletter providing digests of reports that describe scientific anomalies; that is, those observations and facts that challenge prevailing scientific paradigms. Over 2000 Science Frontiers digests have been published since 1976.

These 2,000+ digests represent only the tip of the proverbial iceberg. The Sourcebook Project, which publishes Science Frontiers, also publishes the Catalog of Anomalies, which delves far more deeply into anomalistics and now extends to sixteen volumes, and covers dozens of disciplines.

Over 14,000 volumes of science journals, including all issues of Nature and Science have been examined for reports on anomalies. In this context, the newsletter Science Frontiers is the appetizer and the Catalog of Anomalies is the main course.


Subscriptions to the Science Frontiers newsletter are no longer available.

Compilations of back issues can be found in Science Frontiers: The Book, and original and more detailed reports in the The Sourcebook Project series of books.

The publisher

Please note that the publisher has now closed, and can not be contacted.


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Search results for: pennsylvanian period

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... Science Frontiers ONLINE No. 71: Sep-Oct 1990 Issue Contents Other pages Home Page Science Frontiers Online All Issues This Issue Sourcebook Project Sourcebook Subjects Pennsylvanian time-scale problems The advent of radiometric dating seemed to solve once and for all the problem of assigning dates to the key events in the earth's history. Indeed, all of the reference books confidently label charts with firm dates for the appearance of fishes, the demise of the dinosaurs, and so on. Alas, things are not quite as certain as they appear. Radiometric dating is not all that precise; errors may be large indeed. Take the Pennsylvanian period for example. It is part of the Carboniferous period, when many of the great coal deposits were laid down. The classical duration of the Pennsylvanian - ... used in many texts -- is 34 million years. A meticulous new study of central European stratigraphy now pegs the Pennsylvanian as spanning only 19 million years. Now that's a 44% change! This new figure for the duration of the Pennsylvanian has already cast doubt on the origin of the famous Pennsylvanian cyclothems (repetitive strata) in North America. It had been thought that these seemingly cyclic deposits were correlated with sea level changes forced by variations in the earth's orbit (the Milankovitch periods). With this substantial compression of Pennsylvan-ian time, this correlation falls apart. The cyclothems, which are of impressive area and thickness, now seem to have been created by some other, still unrecognized phenomenon. (Klein, George deV.; "Pennsylvanian Time Scales and ...
Terms matched: 2  -  Score: 310  -  15 May 2017  -  URL: /sf071/sf071g11.htm
... Sep-Oct 1990 Other pages Home Page Science Frontiers Online All Issues Last Issue Next Issue Sourcebook Project Sourcebook Subjects Contents Archaeology Florida's circular canals GREAT ANCIENT CIVILIZATIONS IN AMAZONIA? RIDICULOUS! The sweet track Another anomaly bites the dust Astronomy Modern technology gets Two hot spots on mercury Astronomers cope with both Biology NATURE COMMUNICATES IN MYSTERIOUS WAYS Those amazing insects The bombardier beetle pulse-jet Duesberg revisited Geology Pennsylvanian time-scale problems OF TIME AND THE CORAL - AND OTHER THINGS, TOO Paleomagnetic pitfalls What's another dipole or two? Wyoming: a periodic spring WYOMING: IS OLD FAITHFUL A STRANGE ATTRACTOR? Geophysics Ball lightning studies LUNAR ECLIPSES AND RADIO PROPAGATION General Novel forms of matter ...
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