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You can search within the following fields:
| SITE NUMBER | DATE | LAB NUMBER | MATERIAL |
| General: | The search is not case sensitive, nor is it a "whole word" search. "For example, "Mytil" will return the same results as ""mytilus" in the Material field. From the tabular search results you can access an individual date by clicking on the site number. That will take you to the individual listings, which include more data than can be included in the tabular listings. |
| Site number: | This field is for trinomials only. To locate a specific site: for all counties except San Diego use leading 0s to make a 4-digit number (SCR-0009); San Diego County requires a 5-digit number (SDI-10001). To locate all dates within a specific county, search for the county abbreviation (three characters for counties, four for the islands). In cases where there is possible confusion with an island (SCR vs. SCRI) search for "SCR-" and you will get only Santa Cruz County. (A full list of abbreviations is found on the Counties of California map.) |
| Date: | When you search for a date you can search for "Date=", "Date>" or "Date<" in each of the two search boxes. We realize this is limiting and we hope to add a third search box in the future, but don't wait up. The date returned will generally be measured age. Any deviation from this, such as conventional age, 12C/13C adjusted, or calibrated age, etc. should be noted in Comments. Caution: Many dates are something other than measured age, and we have no idea what. This is because archaeologists frequently fail to specify in which form their dates are reported. Older dates (and some current ones) may be included herein as conventional age, recalibrated age, or some other undisclosed measure. There was, and still is, no standardization in how dates are reported in the literature. Dates are even reported as calibrated age, with no hint as to the C13/C12 or Delta-R which may have been used. This field has a leading field "Symbol" for a "<" or ">" in front of the date. A few of the dates entered into this database in the early 1980s did not get a symbol where needed. |
| Lab number: | For most laboratories use the lab prefix plus leading 0s to make a 4-digit number (WSU-0789); for "I=" dates use a 5 digit number (I-09409), and for "Beta-" dates use a 6-digit number (Beta-034567). When you search for a laboratory number you can use a shortened search (Beta-001 or Beta-) and the resulting data will be sorted by laboratory number. (However, a search for "Beta" will produce over 2,000 dates.) |
| Material: |
You can search for any variation on the material. For example, "mytilus" or "charcoal" or "bead" will all return useful results. However, some dates are entered as "charred residue"or "charred acorn" or "charred tules" instead of charcoal. Still others specify "ash" or "carbon, ash" or some other variation. Knowing whether a sample was obtained from one or multiple pieces of material is critical to understanding the reliability of the resulting date. Very few dates includes this critical bit of information, but we have added it where available. |
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| ADDITIONAL NOTES ON THE FORMAT |
| Location: | This is a generic location, city or town, cute site name, or other non-trinomial site number. P numbers may not be used. This field is to assist those who are not able to remember several thousand site numbers off the top of their heads. |
| Provenience: | In order to save column space in the original print format, the standard form for provenience (i.e., "Unit 3, 10-20 cm") was abbreviated "3: 10-20 cm." It has not yet been changed back. |
| Archaeologist: | Companies come and companies go, especially in Southern California. Who is the archaeologist who actually knows something about the sample? |
| Cal 2 sigma: | The calibration should be the one from the C14 laboratory data sheet. There are lots of ways to calibrate dates, and they change over time, so that is the only way to keep things somewhat standardized. If the laboratory sheet did not include a calibrated date, this should be left blank. If a non-standard Delta-R is used that should be noted in the Comments section. |
| C13/C12: | The actual measurement from the laboratory. Estimates not allowed. If there is a "-" in this field it is known that there was no C13/C12 obtained. |
| Reference: | A reference to a written report, published or unpublished. |
| Comment: | Put in anything that may be important to understanding the date. This is particularly needed when the date is something other than measured age (conventional age, calibrated age, etc.). In that case, please specify what kind of a date it is! |
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California Radiocarbon Dates went through several computer printout editions in the early 1980s (on a Radio Shack Model I no less), followed by eight formal editions between 1982 and 1996. It finally reached the point where the publication became too large and too much work to publish on paper every year or two. Now that we have the internet we are converting everything to that format.
As we convert to the internet, have over 5,380 dates in our database, but there are thousands of existing dates which we do not have, and new dates are being generated at an unprecedented rate. A few radiocarbon laboratories are willing to provide us some "fill-in" information, but can't help much due to limited staff and budgets. Private labs, such as Beta Analytic, understandably cannot release their clients' data, though they have offered to help in other ways.
Some archaeological reports, particularly CRM reports, still do not contain details on radiocarbon dates--they are "being processed" when the report is finished and sent to the Information Centers. Others include a few data sheets from radiocarbon laboratories as an appendix, which is good, but provide no details on sample selection, interpretation, etc. in the text. Still other archaeologists include a "calibrated" date with no details on lab number, C12/C13, measured age, conventional age, any Delta-R which may have been used, etc. And you would be amazed at how many archaeologists are still using a handful of shell fragments for their dating samples; they still believe they are getting usable results! (See Dating 103 for some basic notes on sample selection.)
To make matters worse, the mass of radiocarbon information on file with the clearinghouses is not available to us---the Information Centers cannot afford to voluntarily track down all of the dates from thousands of scattered files and reports, and we cannot afford to pay them for this research, or to visit each clearinghouse for several days each year to do it ourselves. We rely on individual archaeologists for the bulk of our information.
In addition to the difficulty in obtaining dates, there is also a problem in obtaining trinomial site numbers to go with the information. This problem is critical in San Diego County where a significant percentage of the dates are not accompanied by real site numbers! And to make things worse, the State of California, in its infinite wisdom, is now trying to foist "P" numbers on us.
We welcome any help from fellow archaeologists in adding to this database.
