The radiocarbon dating method is based on the fact that radiocarbon is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen.
The resulting radiocarbon combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire in a sample from a dead plant or animal such as a piece of wood or a fragment of bone provides information that can be used to calculate when the animal or plant died.
Love-hungry teenagers and archaeologists agree: dating is hard.
But while the difficulties of single life may be intractable, the challenge of determining the age of prehistoric artifacts and fossils is greatly aided by measuring certain radioactive isotopes.
The method was developed by Willard Libby in the late 1940s and soon became a standard tool for archaeologists.
Libby received the Nobel Prize in Chemistry for his work in 1960.
Probably the most important factor to consider when using radiocarbon dating is if external factors, whether through artificial contamination, animal disturbance, or human negligence, contributed to any errors in the determinations.Research has been ongoing since the 1960s to determine what the proportion of in the atmosphere has been over the past fifty thousand years.The resulting data, in the form of a calibration curve, is now used to convert a given measurement of radiocarbon in a sample into an estimate of the sample's calendar age.Because of the half-lives of 238U, 232nd, and 40K are very long, their concentrations in the object, and hence the radiation dose they provide per year, have remained fairly constant. 74th Court Miami, FL 33155 (305) 667-5167 FAX (305) 663-0964 Biocams International, Inc 13018 SW 120 Street Miami, FL 33186 (305) 663-0886 FAX (305) 631-3434 Center for Accelerator Mass Spectrometry PO Box 808, L-397 Livermore, CA 94550 Columbia University Geochemistry Department Lamont-Doherty Earth Observatory Palisades, NY 10964 (914) 365-8505 FAX (914) 365-8155 Desert Research Institute Water Resources Center Radiocarbon Laboratory PO Box 19040 Las Vegas, NV 89132-0040 (702) 895-0416 FAX (702) 895-0427 Geochron Laboratories A division of Krueger Enterprises, Inc.The most suitable type of sample for thermoluminescence dating is pottery, though the date gotten will be for the last time the object was fired. 711 Concord Avenue Cambridge, MA 02138 (617) 876-3691 FAX (617) 661-0148 Illinois State Geological Survey Isotope Geochemistry Laboratory Geochemistry Section 615 East Peabody Drive Urbana, IL 61820 (217) 333-9083 FAX (217) 244-7004 Los Angeles County Museum of Art 5905 Wilshire Boulevard Los Angeles, CA 90036 (213) 857-6161 FAX (213) 931-7347 Purdue University Purdue Rare Isotope Measurement Laboratory 1396 Physics Building West Lafayette, IN 47907-1396 (317) 494-6516 FAX (317) 494-0706 Teledyne Isotopes 50 Van Buren Avenue Westwood, NJ 07675 (201) 664-7070 FAX (201) 664-5586 Texas A&M University Department of Oceanography College Station, TX 77843 (409) 845-3651 United States Geological Survey 345 Middlefield Road Menlo Park, CA 94025 (415) 329-4685 FAX (415) 329-4684 United States Geological Survey National Center, 971 Reston, VA 22092 (703) 648-5350 FAX (703) 648-5310 United States Geological Survey, WRD Box 25046, Mail Stop 421 Denver Federal Center Denver, CO 80225 (303) 236-5178 FAX (303) 236-5047 University of Arizona Geosciences Department Laboratory of Isotope Geochemistry Tuscon, AZ 85721 (520) 621-8888 FAX (520) 621-2672 University of Arizona NSF-Arizona AMS Laboratory PAS Building 81 Tuscon, AZ 85721 (520) 621-6810 FAX (520) 621-9619 University of California Institute of Geophysics and Planetary Physics Archaeology Department Los Angeles, CA 90024 (310) 825-4169 FAX (310) 206-3051 University of California Institute of Geophysics and Planetary Physics Department of Anthropology Riverside, CA 92512 (909) 787-5521 FAX (909) 787-5409 University of California, Irvine Department of Earth Science Radiocarbon Laboratory PSRF 207 Irvine, CA 92717 (909) 725-2116 FAX (909) 725-3256 University of Georgia Center for Applied Isotope Studies 120 Riverbend Road Athens, GA 30602-4702 (706) 542-1395 FAX (706) 542-6106 University of Miami Rosenstiel School of Marine and Atmospheric Science Miami, FL 33149 (305) 361-4100 FAX (305) 361-4112 University of Rochester Nuclear Structure Research Laboratory Rochester, NY 14627 (716) 275-4944 FAX (716) 275-8527 University of Texas at Austin J. Pickle Research Campus Radiocarbon Laboratory Mail Code 77600 Austin, TX 78712 (512) 471-6600 FAX (612) 471-5973 University of Washington Department of Geological Sciences Quaternary Isotope Laboratory AJ-20 Seattle, WA 98195 (206) 685-1735 FAX (206) 543-3836 University of Wisconsin - Madison Center for Climatic Research 1225 West Dayton Street Madison, WI 53706 (608) 262-7328 FAX (608) 262-5964 Woods Hole Oceanographic Institution Mc Lean Laboratory National Ocean Sciences AMS Facility Woods Hole, MA 002543 (508) 457-2000x2585 FAX (508) 457-2183 Daybreak Nuclear & Medical Systems Inc. Suess effect on biomarkers used to determine sediment provenance from land-use changes.