Radiocarbon age dating of biological material from cores collected off central California in 1999, 2006, and 2019

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   McGann, Mary, Paull, Charles K., Lundsten, Eve, Gwiazda, Roberto, Walton, Maureen A.L., Nieminski, Nora M., Lorenson, Thomas D., and Lee, Homa J., 20230925, Radiocarbon age dating of biological material from cores collected off central California in 1999, 2006, and 2019: data release DOI:10.5066/P9FWTKZQ, U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz, California.

   Online Links:

   • https://doi.org/10.5066/P9FWTKZQ

   Other_Citation_Details:

   Suggested Citation: McGann, M., Paull, C.K., Lundsten, E., Gwiazda, R., Walton, M.A.L., Nieminski, N.M., Lorenson, T.D., and Lee. H.J., 2023, Radiocarbon age dating of biological material from cores collected off central California in 1999, 2006, and 2019: U.S. Geological Survey data release, https://doi.org/10.5066/P9FWTKZQ.

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -121.926150
   East_Bounding_Coordinate: -121.300355
   North_Bounding_Coordinate: 35.776725
   South_Bounding_Coordinate: 35.077682
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 25-Jun-1999

   Ending_Date: 10-Nov-2019

   Currentness_Reference:

   Ground condition at time data were collected.

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: Comma-separated values
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point (150)
   2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is North American Datum of 1927.
      The ellipsoid used is Clarke 1866.
      The semi-major axis of the ellipsoid used is 6378206.4.
      The flattening of the ellipsoid used is 1/294.978698214.
      
7. How does the data set describe geographic features?

   Attribute table

   Table containing attribute information associated with the data set (Source: Producer defined.)

   USGS_FAN

   Unique U.S. Geological Survey field activity identifier. (Source: Producer defined) Unique U.S. Geological Survey field activity identifier.

   Core_ID

   name of core (Source: Producer defined.) Unique alphanumberic identifier for the core given in the field. JPC refers to a jumbo piston core; VC refers to a vibracore; PC refers to a push core.

   Cruise_Number

   Unique alphanumeric identifier given to the cruise. BH refers to the M/V Bold Horizon; OO refers to the M/V Ocean Olympic. NAN indicates the parameter was not determined because the cruise was on the Monterey Bay Aquarium Research Institute's R/V Western Flyer and no cruise number is assigned to these cruises. (Source: Producer defined.)

   Value	Definition
   Presence or absence of each alphanumeric identifier	Cruise was on the M/V Bold Horizon, the M/V Ocean Olympic, or the R/V Western Flyer.

   Dive_Number

   Unique alphanumeric identifier given to the dive. DR refers to the Monterey Bay Aquarium Research Institute's remotely operated vehicle Doc Ricketts; T refers to the Monterey Bay Aquarium Research Institute's remotely operated vehicle Tiburon. NAN indicates the core was not obtained with an ROV but off the side of the vessel. (Source: Producer defined.) List of Dive ID numbers

   Date_Collected

   Date [YYYY-MM-DD] (Source: Producer defined.)

   Range of values
   Minimum:	1999-06-25
   Maximum:	2019-11-10

   Latitude

   Latitude of sample location. 9999 indicates the parameter was not determined. (Source: Producer defined.)

   Range of values
   Minimum:	35.077682
   Maximum:	35.776725
   Units:	decimal degrees
   Resolution:	0.000001

   Longitude

   Longitude of sample location. 9999 indicates the parameter was not determined. (Source: Producer defined.)

   Range of values
   Minimum:	-121.300355
   Maximum:	-121.926150
   Units:	decimal degrees
   Resolution:	0.000001

   Water_Depth_m

   Water depth of core collection. 9999 indicates the parameter was not determined. (Source: Producer defined.)

   Range of values
   Minimum:	636.00
   Maximum:	1126.00
   Units:	meters
   Resolution:	0.01

   Core_Section_Number

   Section number of core. Core sections are assigned from the top of the core to the bottom in intervals of 150 cm (for example, section 1 is 0-150 cm, section 2 is 150-300 cm). (Source: Producer defined.)

   Range of values
   Minimum:	1
   Maximum:	8
   Units:	section
   Resolution:	1

   Sample_Upper_Depth_Limit_cm

   Upper depth of sampling interval in core in centimeters. (Source: Producer defined.)

   Range of values
   Minimum:	0.0
   Maximum:	698.5
   Units:	centimeters
   Resolution:	0.1

   Sample_Lower_Depth_Limit_cm

   Lower depth of sampling interval in core in centimeters. (Source: Producer defined.)

   Range of values
   Minimum:	2.0
   Maximum:	700.5
   Units:	centimeters
   Resolution:	0.1

   Material_Radiocarbon_Dated

   Biological specimen type (Source: Producer defined.)

   Value	Definition
   Presence or absence of biological type	Biological type used for radiocarbon dating.

   Radiocarbon_Sample_Weight_mg

   The weight of the radiocarbon sample measured on a microbalance prior to submission for dating. 9999 indicates the parameter was not determined. (Source: Producer defined.)

   Range of values
   Minimum:	1.59
   Maximum:	15.41
   Units:	milligrams
   Resolution:	0.01

   Approximate_Radiocarbon_Sample_Weight_mg

   An approximate weight of the radiocarbon sample prior to submission for dating, based on an estimated from pre-weighed standards instead of weighing on a microbalance. 9999 indicates the parameter was not determined. (Source: Producer defined.)

   Range of values
   Minimum:	2
   Maximum:	14
   Units:	milligrams
   Resolution:	1

   NOSAMS_Accession_Number

   Lab specific ID from AMS facility. (Source: Producer defined.) List of lab IDs

   Fraction_Modern

   Fraction modern is a measurement of the deviation of the delta Carbon 14 to delta Carbon 12 ratio of a sample from modern carbon (Stuiver and Polach, 1977; Stuiver, 1980). (Source: Producer defined.)

   Range of values
   Minimum:	-0.0006
   Maximum:	0.8942
   Units:	unitless
   Resolution:	0.0001

   Fraction_Modern_Error

   Fraction modern error is a measurement of the deviation of the delta Carbon 14 to delta Carbon 12 ratio of a sample from modern carbon (Stuiver and Polach, 1977; Stuiver, 1980). (Source: Producer defined.)

   Range of values
   Minimum:	0.0003
   Maximum:	0.0029
   Units:	unitless
   Resolution:	0.0001

   Conv_Radiocarbon_Age_yrs_BP

   Conventional Radiocarbon Age calculated using the radiocarbon decay equation (Stuiver and Polach, 1977; Stuiver, 1980) with BP (Before Present) equal to 1950. Values with the "greater than" sign denote those samples in which the limit of the measuring instrument was exceeded. The maximum range domain is greater than 52,000 years. (Source: Producer defined.)

   Range of values
   Minimum:	900
   Maximum:	52000
   Units:	years
   Resolution:	10

   Conventional_Radiocarbon_Age_Error

   Standard error for Conventional Radiocarbon Age. 9999 indicates the parameter was not determined. (Source: Producer defined.)

   Range of values
   Minimum:	15
   Maximum:	6700
   Units:	years
   Resolution:	5

   Delta_C13_per_mil

   delta C13 is a measure of the ratio of stable isotopes Carbon13 to Carbon12, reported in parts per thousand (per mil). 9999 indicates the parameter was not determined. (Source: standard reporting value in isotope chemistry)

   Range of values
   Minimum:	-1.35
   Maximum:	1.03
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   Delta_C14_per_mil

   The relative difference between the absolute international standard (base year 1950) and sample activity corrected for age and delta Carbon13. (Source: defined in Stuiver and Polach (1977) and Stuiver (1980).)

   Range of values
   Minimum:	-1000.58
   Maximum:	-113.25
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   dR_yrs_BP

   The value of the regional deviation from the ocean reservoir age as defined by Ingram and Southon (1996). The regional marine radiocarbon reservoir correction (delta R) used for the planktic foraminiferal samples was delta R equals 59 and delta R equals 1100 years for the benthic foraminiferal samples. (Source: Producer defined.)

   Range of values
   Minimum:	59
   Maximum:	1100
   Units:	year
   Resolution:	1

   dR_error_yrs_BP

   Error in the value of the regional deviation from the ocean reservoir age as defined by Ingram and Southon (1996). The regional marine radiocarbon reservoir correction error used for the planktic foraminiferal samples was delta R error equals 134 years and delta R error equals 200 years for the benthic foraminiferal samples. (Source: Producer defined.)

   Range of values
   Minimum:	134
   Maximum:	200
   Units:	year
   Resolution:	1

   Min_Calib_Age_cal_yrs_BP_95_percent_conf

   Minimum Calibration Age in calibrated years BP at the 95 percent confidence level (2 sigma range) with BP (Before Present) equal to 1950. Determined using the CALIB 8.2 program (Stuiver and Reimer, 1993) and the Marine20 calibration curve (Heaton and others, 2020). 9999 indicates the parameter was not determined. (Source: defined in Heaton and others (2020).)

   Range of values
   Minimum:	4
   Maximum:	49935
   Units:	year
   Resolution:	1

   Max_Calib_Age_cal_yrs_BP_95_percent_conf

   Maximum Calibration Age in calibrated years BP at the 95 percent confidence level (2 sigma range) with BP (Before Present) equal to 1950. Determined using the CALIB 8.2 program (Stuiver and Reimer, 1993) and the Marine20 calibration curve (Heaton and others, 2020). 9999 indicates the parameter was not determined. (Source: defined in Heaton and others (2020).)

   Range of values
   Minimum:	512
   Maximum:	54990
   Units:	year
   Resolution:	1

   Med_Calib_Age_cal_yrs_BP_95_percent_conf

   Median Calibration Age in calibrated years BP at the 95 percent confidence level (2 sigma range) with BP (Before Present) equal to 1950. Modern equal to greater than 1950. Determined using the CALIB 8.2 program (Stuiver and Reimer, 1993) and the Marine20 calibration curve (Heaton and others, 2020). 9999 indicates the parameter was not determined. (Source: defined in Heaton and others (2020).)

   Range of values
   Minimum:	296
   Maximum:	52876
   Units:	year
   Resolution:	1

   Med_Calib_Age_Correc_Error_cal_yrs_BP

   Median Calibration Age error in calibrated years BP with BP (Before Present) equal to 1950. 9999 indicates the parameter was not determined. Calculated using CALIB 8.2 software (Stuiver and Reimer, 1993) and the Marine20 calibration curve (Heaton and others, 2020). (Source: defined in Heaton and others (2020).)

   Range of values
   Minimum:	135
   Maximum:	4502
   Units:	year
   Resolution:	1

   Entity_and_Attribute_Overview:

   The first line of the comma-separated values file is a header line.

   Entity_and_Attribute_Detail_Citation: U.S. Geological Survey
   

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Mary McGann
   • Charles K. Paull
   • Eve Lundsten
   • Roberto Gwiazda
   • Maureen A.L. Walton
   • Nora M. Nieminski
   • Thomas D. Lorenson
   • Homa J. Lee
2. Who also contributed to the data set?
3. To whom should users address questions about the data?
   U.S. Geological Survey, Pacific Coastal and Marine Science Center

   Attn: PCMSC Science Data Coordinator

   2885 Mission Street

   Santa Cruz, CA
   

   650-329-4979 (voice)

   pcmsc_data@usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 2022 (process 1 of 1)

   Samples for radiocarbon analysis were measured by accelerator mass spectrometry (AMS) at the National Ocean Sciences AMS (NOSAMS) Facility of Woods Hole Oceanographic Institution. The radiocarbon ages were obtained by a ratio of 14C to 12C using a 14C half-life of 5568 years (Stuiver and Polach, 1977) and then were converted to calibrated calendar ages (cal years BP), with BP (Before Present) equal to 1950, using the CALIB 8.2 program (Stuiver and Reimer, 1993; website accessed in 2022 and 2023) and the Marine20 calibration curve (Heaton and others, 2020). The calibrated ages are reported as the median probability ages at the 95 percent confidence level (2 sigma range). The regional marine radiocarbon reservoir correction (delta R), as defined by Ingram and Southon (1996), used for the planktic foraminiferal samples (delta R equals 59) was based on 40 samples located from 35 degrees North latitude to 40 degrees North latitude in the 14CHRONO Marine 20 Reservoir Database (Reimer and Reimer, 2001, accessed in 2022 at http://calib.org/marine/), and (delta R equals 1100) years for the benthic foraminiferal samples was a reinterpretation of Kienast and McKay, 2001 based on Heaton and others, 2020. The error in the values of the regional deviation were based on the same data set and were delta R error equals 134 for the planktic foraminiferal samples and delta R error equals 200 years for the benthic foraminiferal samples.

3. What similar or related data should the user be aware of?
   Stuiver, M., and Polach, H.A., 1977, Discussion: reporting of 14C data.

   Online Links:

   • https://doi.org/10.1017/S0033822200003672

   Other_Citation_Details:

   Stuiver, M., and Polach, H.A., 1977, Discussion: Reporting of 14C data: Radiocarbon, v. 19, p. 355-363.

   Stuiver, M., 1980, Workshop on 14C data reporting.

   Online Links:

   • https://doi.org/10.1017/S0033822200010389

   Other_Citation_Details:

   Stuiver, M., 1980, Workshop on 14C data reporting. Radiocarbon, v. 2, p. 964-966.

   Stuiver, M., and Reimer, P.J., 1993, Extended 14C Data Base and Revised CALIB 3.0 14C Age Calibration Program.

   Online Links:

   • https://doi.org/10.1017/S0033822200013904

   Other_Citation_Details:

   Stuiver, M., and Reimer, P.J., 1993: Radiocarbon, v. 35, p. 215-230.

   Ingram, B.L., and Southon, J.R., 1996, Reservoir ages in eastern Pacific coastal and estuarine waters.

   Online Links:

   • https://doi.org/10.1017/S0033822200030101

   Other_Citation_Details:

   Ingram, B.L., and Southon, J.R., 1996, Reservoir ages in eastern Pacific coastal and estuarine water: Radiocarbon, v. 38, p. 573-582.

   Kienast, S.S., and McKay, J.L., 2001, Sea surface temperatures in the subarctic northeast Pacific reflect millennial-scale climate oscillations during the last 16 kyrs.

   Online Links:

   • https://doi.org/10.1029/2000GL012543

   Other_Citation_Details:

   Kienast, S.S., and McKay, J.L., 2001, Sea surface temperatures in the subarctic northeast Pacific reflect millennial-scale climate oscillations during the last 16 kyrs: Geophysical Research Letters, v. 2, p. 1563-1566.

   Reimer, P.J., and Reimer, R.W., 2001, A marine reservoir correction database and on-line interface. Accessed in 2022 as: 14CHRONO Marine 20 Reservoir Database.

   Online Links:

   • https://calib.org/marine/

   Other_Citation_Details:

   Reimer, P.J., and Reimer, R.W., 2001, A marine reservoir correction database and on-line interface: Radiocarbon v. 43, p. 461-463.

   Heaton, T.J., Kohler, P., Butzin, M., Bard, E., Reimer, R.W., Austin, W.E.N., Ramsey, C. Bronk, Grootes, P.M., Hughen, K.A., Kromer, B., Reimer, P.J., Adkins, J., Burke, A., Cook, M.S., Olsen, J., and Skinner, L.C., 2020, The marine radiocarbon age calibration curve (0-55,000 ca BP).

   Online Links:

   • https://doi.org/10.1017/RDC.2020.68

   Other_Citation_Details:

   Heaton, T.J., Kohler, P., Butzin, M., Bard, E., Reimer, R.W., Austin, W.E.N., Bronk Ramsey, C., Grootes, P.M., Hughen, K.A., Kromer, B., Reimer, P.J., Adkins, J., Burke, A., Cook, M.S., Olsen J., and Skinner, L.C., 2020, Marine20 - The marine radiocarbon age calibration curve (0-55,000 ca BP): Radiocarbon, v. 62, p. 779-820.

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?
   The age and associated error of the radiocarbon ages are calculated from the fraction modern and its error and the ages are reported according to conventions that the radiocarbon community has adopted. The Conventional Radiocarbon Age is always reported rounded (the NOSAMS convention is reported at https://www2.whoi.edu/site/nosams/calculations-and-reporting-of-results). The fraction modern values and the ages are listed in this data release, so there can be no misinterpretations of these data. The age for the calibration (not rounded) can be calculated using -8033 multiplied by the log normal of the fraction modern.
2. How accurate are the geographic locations?
   A formal accuracy assessment of the horizontal positional information in the data set has not been conducted. The horizontal accuracy was determined with the ship's GPS navigation (SIMRAD MX 512 Navigation System) which is accurate to 5 m.
3. How accurate are the heights or depths?
   A formal accuracy assessment of the vertical positional information in the data set has not been conducted. Depth was determined using a using a Knudsen 320B/R Engineering System with a stated accuracy of 5 percent.
4. Where are the gaps in the data? What is missing?
   Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the metadata for each part of this data release carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   Data were checked for logical consistency by the NOSAMS staff before release, and by the USGS staff compiling this data release, to confirm that numerical values were not outside a reasonable range for a particular field.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey - ScienceBase

   Denver Federal Center, Building 810, Mail Stop 302

   Denver, CO
   

   1-888-275-8747 (voice)

   sciencebase@usgs.gov
2. What's the catalog number I need to order this data set? These data are available in a comma-delimited text file (Central_California_AgeData_data.csv) which contains results from radiocarbon age dating of biological material from cores collected off central California in 1999, 2006, and 2019.
3. What legal disclaimers am I supposed to read?
   Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	.csv file in format comma-separated values (version Microsoft Excel 16.68 for Mac) Size: 0.03911
     Network links:	https://www.sciencebase.gov/catalog/file/get/63bb2535d34e92aad3cd27ae https://doi.org/10.5066/P9FWTKZQ

   • Cost to order the data: None.

5. What hardware or software do I need in order to use the data set?
   These data can be viewed with any text editor software.

Who wrote the metadata?

Dates:

Last modified: 25-Sep-2023

Metadata author:

U.S. Geological Survey, Pacific Coastal and Marine Science Center

Attn: PCMSC Science Data Coordinator

2885 Mission Street

Santa Cruz, CA

831-427-4747 (voice)

pcmsc_data@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)