This award will support a two-day workshop to establish data reporting requirements and procedures for the U-series dating method. The effort is between the EarthChem and EARTHTIME projects, and has some sponsorship from the British Geological Survey (BGS). The workshop will be held on June 21 and 22, 2010, at the BGS in Nottingham, UK. The main technical challenges are to establish required reporting requirements including specific data and metadata items. Optional requirements will also be identified. In addition, we will explore software approaches via data reduction packages using XML communication or web form interaction to submit data to the Geochron database at EarthChem.
The U-series dating method relies on the time it takes the various intermediate but still radioactive daughter products of Uranium decay to reach a stable configuration. At first, the daughter elements are not present in equilibrium concentration ? this is established over a period of a few hundred thousand years. The method is very powerful for establishing ages of recent volcanic and marine deposits, particularly on samples less than around half a million years old. The workshop is to make the reporting of results complete and transparent. In this way, samples from different labs and/or using different procedures and equipment can be compared on an equal basis. In addition, the workshop should establish a way for these data to be reported and ultimately discovered by a wide variety of users, including researchers, students, and other interested individuals. In this way, events such as volcanic eruptions, sea level and climate changes, and a myriad of other recent geological phenomenon can be better understood and integrated with related data.
A significant fraction of our knowledge of the ages of geological materials that are 300,000 years old or younger comes from the U-series data method. These ages are critical to understanding climate and environmental changes as well as a host of geological processes such as the amount of time magma resides in the crust before erupting. The accuracy of these dates, however, is often less well quantified (with respect to precision) than some other methods: this limits the usefulness of the data to some extent. In addition, much of the basic information about the method application and samples are not captured in current data reporting schemes and methods reported in journals. In light of the importance of U-series dating, some discussion of the issues and pitfalls in the subject is warranted with a view to producing guidelines on the acquisition, interpretation, reporting, and archiving of U-series data. For this reason, a small, focused workshop was held to address certain aspects of data reporting and best practices for the U-series method. The conveners were from the US-NSF EarthChem and EARTHTIME projects, Woods Hole Oceanographic Institution, and the British Geological Survey. The workshop was attended by 16 researchers from the US, UK, and Europe. Overall, the workshop was successful in meeting the goals of the organizers. One important aspect with a broad impact is that a clear path to data archiving and submittal, including the items to be reported, was determined. This will make the data much more complete and interpretable. Of intellectual impact was that various aspects of data reduction to produce ages and error analysis were also done. This will allow for more rigorous application of the U-series method. One aspect thought important was to develop a set of test materials of know composition to send to laboratories around the world to analyze. In this way, any intra-laboratory bias can be assessed. This activity has both intellectual and broad impact to the larger geoscience community. A copy of the final workshop report is posted at: www.earthchem.org/sites/earthchem.org/files/U-Series%20Report%20Final.pdf.
