The purpose of the catalogue is to assemble data from the refraction surveys in the Arctic Ocean. The catalogue shows the distribution and results of refraction experiments that are useful for defining features from the seabed to the crust/mantle boundary. This information is basic for scientific and economic evaluation of the Arctic Ocean.
Prior to the catalogue the extent, quality and significance of the seismic refraction sections in the region were unknown. The cost and difficulty of acquiring this knowledge, due to the ice cover of the Arctic Ocean, were greater than in other oceans and a special effort to compile it was thought worthwhile. In addition, data sets collected by scientists in the former Soviet Union were not readily available to scientists in western countries. Table I provides a brief summary of the data. Information presented in the catalogue is incomplete as yet. Assembling the seismic sections requires that the data are published or contacting the scientists and/or organizations who originally collected it and getting their permission to include it. In addition, there are other institutions that have not released their data to the public. Scientists and institutions who have been missed are asked to submit their data so the catalogue can be updated.
The catalogue is available in paper or digital form. In either case an index map will be provided that shows the organization of the data. The files are arranged in geographic groupings and listed alphabetically. The text for each data set is intended to give the reader insight into the quality of the data; for example, in the 1960's seismic profiles were often run with only a few shots and receivers with navigation by sun shots. The reader is expected to use this information in interpreting the final results; in contrast, there are seismic surveys from the 1990's with thousand of shots to multiple ocean bottom seismometers with navigational control from Global Positioning System. The same set of questions is listed for each data entry. It was not possible to obtain all the information for every experiment.
The original data are not included for a number of reasons. In many cases the original data are no longer available. The seismic sections were recorded in many different formats, both analogue and digital. The catalogue contains information on whether it is preserved and where it can be located. A summary of a refraction survey is contained in a velocity-depth function. This is the way the seismic refraction profiles are presented. Information on how the refraction profiles were interpreted is given and includes a range of techniques from using straight line fits of first arrival picks to automated inversion techniques. All of this information must be used in evaluating the significance of the velocity-depth function.
The contents of the catalogue have been bestowed from a number of countries. The seismic refraction profiles were often collected collaboratively by several scientists from different institutions. The acknowledged contributors are those who supplied specially compiled data or measurements not readily available in published literature. The authors of published papers are credited in the reference section of the catalogue files. The largest set of data included is from the shelf and deep water regions adjacent to Norway that was contributed by the University of Oslo. From Russia scientists from the Polar Marine Expedition, Shirshov Instiute of Oceanology and VNIIOkeangeologia contributed data. The Alfred Wegener Institute of Germany supplied recently collected data. The seismic refraction data on the Alaskan margin was collected by the United States Geological Survey. New refraction profiles across Alaska were input into the catalogue. The Geological Survey of Canada has collected seismic data from northern Canada, Baffin Bay, the polar margin and from the deep water areas of the Arctic Ocean. The geological evolution of the Canadian Arctic Archipelago and the Barents Sea are similar; therefore, onshore data from northern Canada have been included.
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