Late Pleistocene coral ages and elevations from south Florida

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?
   Hsia, Scarlette, Toth, Lauren T., Mortlock, Richard A., Stathakopoulos, Anastasios, and Kerans, Charles, 20240621, Late Pleistocene coral ages and elevations from south Florida:.

   This is part of the following larger work.
   Hsia, Scarlette, Toth, Lauren T., Mortlock, Richard A., Stathakopoulos, Anastasios, and Kerans, Charles, 20240621, U-series Ages and Elevation Data of Late Pleistocene Corals From the Florida Keys: U.S. Geological Survey data release doi:10.5066/P9EJBYKZ, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P9EJBYKZ

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -82.9200
   East_Bounding_Coordinate: -80.1267
   North_Bounding_Coordinate: 25.4240
   South_Bounding_Coordinate: 24.4348
   Description_of_Geographic_Extent: Florida Keys Reef Tract, Monroe County, Florida, USA
   

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

   Beginning_Date: 28-Jul-1976

   Ending_Date: 22-Aug-2016

   Currentness_Reference:

   ground condition

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

   Geospatial_Data_Presentation_Form: tabular digital data
   

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 (34)
   2. What coordinate system is used to represent geographic features?
      
7. How does the data set describe geographic features?

   Late_Pleistocene_coral_data_from_south_Florida_and_uncertainties

   Comma-separated values file (.csv) and Microsoft Excel file (.xlsx) containing the U-series data and descriptive collection information (such as sample/core identifier, location, elevation, etc.) for late Pleistocene coral subsamples from coral reef cores collected throughout the Florida Keys. (Source: USGS)

   Sample ID

   Unique identifier for each coral reef core subsample dated in this study. (Source: USGS) Sample IDs were generated by abbreviating information about the subregion where the sample was collected, the site name, the core number, and a unique letter or number for each sample was collected in the core and are formatted as: Subregion abbreviation-Site abbreviation-Core number-Sample letter and/or number, example: BP-PR-1-A.

   USGS Core ID

   The unique identifier for each coral reef core that was subsampled in this study, as defined in Toth and others (2018). (Source: USGS) Core IDs were assigned in Toth and others (2018) using abbreviated information about the subregion, site, and core number and are formatted as: Subregion abbreviation-Site abbreviation-Core number, example: BP-PR-1

   Latitude

   The approximate latitude (in decimal degrees) where the coral reef core was collected. Refer to the Horizontal_Positional_Accuracy_Report section for more information on the horizontal positional accuracy. (Source: USGS)

   Range of values
   Minimum:	24.4348
   Maximum:	25.424
   Units:	decimal degrees

   Longitude

   The approximate longitude (in decimal degrees) where the sample was collected. Refer to the Horizontal_Positional_Accuracy_Report section for more information on the horizontal positional accuracy. (Source: USGS)

   Range of values
   Minimum:	-82.92
   Maximum:	-80.1267
   Units:	decimal degrees

   Water depth (m)

   The water depth in the location where the core was collected as recorded in the field. Negative values indicate that the sample was collected subaerially. Refer to the Vertical_Positional_Accuracy_Report section for more information on the vertical positional accuracy. (Source: USGS)

   Range of values
   Minimum:	-0.2
   Maximum:	11.29
   Units:	meters

   Depth in core (m)

   Approximated depth in the core (measured from the top of the core) of where the sample was collected, in meters (m). (Source: USGS)

   Range of values
   Minimum:	1.83
   Maximum:	16.15
   Units:	meters

   Depth MSL (m)

   The depth, in meters, of the sample relative to mean sea level (MSL), calculated by adding the depth of the sample in the core from the depth of the reef surface where the core was collected. Refer to the Vertical_Positional_Accuracy_Report section for more information on vertical positional accuracy. (Source: USGS)

   Range of values
   Minimum:	6.83
   Maximum:	20.72
   Units:	meters below mean sea level (MSL)

   Water depth uncertainty (2-sigma)

   An approximate 2 standard error (2 sigma) uncertainty associated with estimated water depth where the core was collected. For four cores (LK-MG-2, LK-MG-3, UK-GR-3, and UK-GR-4), there were disagreements in the recorded water depth between field notes, notes on the core box, and/or previous publications describing the cores. As a result, a conservatively high 1 m water depth uncertainty was assigned. The elevations of two other cores (LK-WS-3 and UK-CR-2) were surveyed with high-precision Global Positioning System (GPS) equipment in the field, so benchmark uncertainties (0.004 and 0.015 m) were assigned in place of the water depth uncertainty. Refer to the Vertical_Positional_Accuracy_Report section for more information on vertical positional accuracy. (Source: USGS)

   Range of values
   Minimum:	0.004
   Maximum:	1
   Units:	meters

   Tidal uncertainty (2-sigma)

   An approximate 2-standard error (2 sigma) uncertainty associated with estimated water depth where the core was collected due to when in the tidal cycle the water depth was measured. The tidal uncertainty was estimated as one-half the total tidal range reported for the nearest tidal datum except for the three cores that were surveyed with GPS, for which we assumed no tidal uncertainty. Refer to the Vertical_Positional_Accuracy_Report section for more information on vertical positional accuracy. (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	0.33
   Units:	meters

   Proportion of interval recovered

   The estimated proportional recovery of reef substrate within a particular interval of the core. This value was calculated by dividing the measured surface area of core constituents in an interval by the theoretical surface area of that interval based on the interval length and width as described in Toth and Stathakopoulos (2019). (Source: USGS)

   Range of values
   Minimum:	0.1
   Maximum:	0.85
   Units:	fractional proportion

   Sampling uncertainty (2-sigma)

   An estimate of the 2-standard error (2-sigma) uncertainty to account for the fact that it is not possible to determine the exact position of a sample within a recovered interval of a core (i.e., the material in the interval can shift either during or after coring). This uncertainty was estimated to be one-half the porosity of that interval (i.e., 1-proportional recovery). Calculated using formula: (length of sampled interval - (percent recovery for a given interval multiplied by the length of the sampled interval))/2. For most, used 5 feet (ft) as length of sampled interval based upon core barrel length in noted studies (Toth and others, 2018). (Source: USGS)

   Range of values
   Minimum:	0.107
   Maximum:	2.000
   Units:	meters

   Non-vertical drilling uncertainty (2-sigma)

   An estimate of the 2-standard error (2-sigma) uncertainty in depth of the same in the core based on the possibility that the core did not have exactly vertical penetration into the reef. The uncertainty is estimated to be 0.02 m per meter of core penetration. (Source: USGS)

   Range of values
   Minimum:	0.037
   Maximum:	0.323
   Units:	meters

   Sample thickness uncertainty (2-sigma)

   An estimate of the 2-standard error (2-sigma) uncertainty associated with the thickness of the sample dated, estimated as one-half the sample thickness of 0.01 (Source: USGS)

   Range of values
   Minimum:	0.005
   Maximum:	0.005
   Units:	meters

   Total uncertainty in depth MSL (2-sigma)

   The total 2-standard error (2-sigma) uncertainty in the depth of the samples relative to mean sea level (MSL) calculated as the root-sum-square of all the other elevation uncertainties. (Source: USGS)

   Range of values
   Minimum:	0.397
   Maximum:	2.246
   Units:	meters

   Taxon

   The taxa of the dated coral sample. Corals were generally identified to the species level, but some taxa could only be identified to the genus level. (Source: USGS)

   Value	Definition
   Orbicella spp.	The sample was collected from an Orbicella spp. coral skeleton. Includes corals belonging to the genus Orbicella (O. faveolata, O. franksi, and O. annularis).
   Acropora palmata	The sample was collected from an Acropora palmata coral skeleton.
   Pseudodiploria strigosa	The sample was collected from a Pseudodiploria strigosa coral skeleton.
   Porites astreoides	The sample was collected from a Porites astreoides coral skeleton.
   Pseudodiploria clivosa	The sample was collected from a Pseudodiploria clivosa coral skeleton.
   Siderastraea siderea	The sample was collected from a Siderastraea siderea coral skeleton.

   % Calcite

   The percentage (%) of the coral sample composed of secondary calcite. This is an indicator of diagenetic alteration. (Source: USGS)

   Range of values
   Minimum:	<0.2
   Maximum:	1.7
   Units:	percentage

   U-Th age

   The measured 230Th (U-Th) age of the coral sample used as age of the sample. (Source: USGS)

   Range of values
   Minimum:	7992
   Maximum:	113116
   Units:	years before 1950

   U-Th age uncertainty (2-sigma)

   The 2-standard error (2-sigma) analytical uncertainty of the 230Th age. (Source: USGS)

   Range of values
   Minimum:	17
   Maximum:	784
   Units:	years

   U-Th age BP

   The 230Th (U-Th) age of the coral sample used as age of the sample before present (where present is 1950). (Source: USGS)

   Range of values
   Minimum:	7921
   Maximum:	113045
   Units:	years

   U-Th age BP uncertainty (2-sigma)

   The 2-standard error (2-sigma) analytical uncertainty of the 230Th age in years before present (1950). (Source: USGS)

   Range of values
   Minimum:	17
   Maximum:	784
   Units:	years

   238U (ppm)

   The measured concentration of the isotope 238U in the sample in parts per million (ppm). (Source: USGS)

   Range of values
   Minimum:	2.3515
   Maximum:	3.3438
   Units:	parts per million (ppm)

   238U uncertainty (2-sigma)

   The 2-standard error (2-sigma) analytical uncertainty of the measured 238U of the sample. (Source: USGS)

   Range of values
   Minimum:	0.0007
   Maximum:	0.0018
   Units:	parts per million (ppm)

   232Th (pg/g)

   The measured concentration of the isotope 232Th in the sample in picograms per gram (pg/g). (Source: USGS)

   Range of values
   Minimum:	20.99
   Maximum:	7239.07
   Units:	picograms per gram (pg/g)

   Th232 uncertainty (2-sigma)

   The 2-standard error (2-sigma) analytical uncertainty of the measured 232Th of the sample. (Source: USGS)

   Range of values
   Minimum:	0.0245
   Maximum:	33.578
   Units:	picograms per gram (pg/g)

   234U/238U

   The 234U/238U activity ratio. (Source: USGS)

   Range of values
   Minimum:	1.1083
   Maximum:	1.1558
   Units:	ratio

   234U/238U uncertainty (2-sigma)

   The 2-standard error (2-sigma) uncertainty in the 234U/238U activity ratio. (Source: USGS)

   Range of values
   Minimum:	0.0003
   Maximum:	0.0013
   Units:	ratio

   234U initial

   Corrected initial ?234U (234U initial). (Source: USGS)

   Range of values
   Minimum:	143.8
   Maximum:	214.4
   Units:	ratio

   234U initial uncertainty (2-sigma)

   The 2-standard error (2-sigma) corrected initial ?234U (234U initial). (Source: USGS)

   Range of values
   Minimum:	0.6
   Maximum:	2.2
   Units:	ratio

   230Th/234U

   The 230Th/234U activity ratio. (Source: USGS)

   Range of values
   Minimum:	0.0708
   Maximum:	0.6583
   Units:	ratio

   230Th/234U uncertainty (2-sigma)

   The 2-standard error (2-sigma) uncertainty in the 230Th/234U activity ratio. (Source: USGS)

   Range of values
   Minimum:	0.0001
   Maximum:	0.0034
   Units:	ratio

   230Th/238U

   The 230Th/238U activity ratio. (Source: USGS)

   Range of values
   Minimum:	0.081
   Maximum:	0.7609
   Units:	ratio

   230Th/238U uncertainty (2-sigma)

   The 2-standard error (2-sigma) uncertainty in the 230Th/238U activity ratio. (Source: USGS)

   Range of values
   Minimum:	0.0002
   Maximum:	0.0038
   Units:	ratio

   230Th/232U

   The 230Th/232U activity ratio. (Source: USGS)

   Range of values
   Minimum:	432
   Maximum:	226479
   Units:	ratio

   230Th/232U uncertainty (2-sigma)

   The 2-standard error (2-sigma) uncertainty in the 230Th/232U activity ratio. (Source: USGS)

   Range of values
   Minimum:	0
   Maximum:	685
   Units:	ratio

   238U/232U

   The 238U/232U activity ratio. (Source: USGS)

   Range of values
   Minimum:	1412
   Maximum:	367827
   Units:	ratio

   238U/232U uncertainty (2-sigma)

   The 2-standard error (2-sigma) uncertainty in the 238U/232U activity ratio. (Source: USGS)

   Range of values
   Minimum:	2
   Maximum:	977
   Units:	ratio

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Scarlette Hsia
   • Lauren T. Toth
   • Richard A. Mortlock
   • Anastasios Stathakopoulos
   • Charles Kerans
2. Who also contributed to the data set?
   SPCMSC researchers would like to thank collaborators at Rutgers University and University of Texas at Austin for their contributions with this data release.
3. To whom should users address questions about the data?
   Lauren T. Toth

   U.S. Geological Survey, SOUTHEAST REGION

   Research Physical Scientist

   600 4Th Street South

   St. Petersburg, FL
   

   US

   727-502-8029 (voice)

   727-502-8182 (FAX)

   ltoth@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)

   Coral subsamples were collected from sections of coral reef cores previously collected throughout the Florida Keys, predicted to contain Pleistocene-aged material based on a depositional Pleistocene-Holocene boundary (i.e., a soilstone crust), previously dated samples that were determined to be radiocarbon dead, or depositional textures or diagenetic textures indicative of pre-Holocene material. A tile saw with a diamond blade was used to collect small pieces of internal coral aragonite free of visually observable diagenesis for dating. Those samples were sonicated in warm deionized water to remove any detrital material. Subsamples of each coral core were powdered and analyzed for evidence of secondary alteration to calcite by X-ray diffraction (XRD) in the Department of Chemistry at Rutgers University (Philips XPert Powder Diffractometer) or at the USGS in Denver, Colorado. Only subsamples with <0.2‰ calcite was used for Uranium-Thorium (U-Th) dating. U-Th isotopes were measured using the ThermoScientific NEPTUNEPLUS Multi-collector Inductively Coupled Plasma Mass Spectrometrometer (MC-ICP-MS) at the Department of Earth and Planetary Sciences at Rutgers University following the methods described in Mortlock and others (2005), which were revised in Abdul and others (2016). All dates and activity ratios were calculated using half-lives published in Cheng and others (2013). These data were used to estimate ages before present (relative to 1950) with 2? uncertainties.

3. What similar or related data should the user be aware of?
   Williams, Breanna N., Schreppel, Heather A., Reich, Christopher D., Smith, Kathryn E.L., Tiling-Range, Ginger, Stalk, Chelsea A., Douglas, Steven H., Dadisman, Shawn V., Flocks, James G., Toth, Lauren T., and Stathakopoulos, Anastasios, 20130725, St. Petersburg Coastal and Marine Science Center's geologic core and sample database: Esri, ArcGIS Online.

   Online Links:

   • https://doi.org/10.5066/F7319TR3

   Hsia, Scarlette, Toth, Lauren T., Mortlock, Richard, and Kerans, Charles, 20240723, Re-evaluating Marine Isotope Stage 5a Paleo-sea-level trends from across the Florida Keys Reef Tract, Florida: Quaternary Science Advances Article 100222, Elsevier, Online.

   Online Links:

   • https://doi.org/10.1016/j.qsa.2024.100222

   Mortlock, Richard A., Fairbanks, Richard G., Chiu, Tzu-chien, and Rubenstone, James, 20050201, 230Th/234U/238U and 231Pa/235U ages from a single fossil coral fragment by multi-collector magnetic-sector inductively coupled plasma mass spectrometry: Geochimica et Cosmochimica Acta Volume 69, Issue 3, Elsevier BV, Amsterdam.

   Online Links:

   • https://doi.org/10.1016/j.gca.2004.06.033

   Other_Citation_Details: Pages 649-657
   

   Abdul, Nicole A., Mortlock, Richard A., Wright, James D., and Fairbanks, Richard G., 20160220, Younger Dryas sea level and meltwater pulse 1B recorded in Barbados reef crest coral Acropora palmata: Paleoceanography Volume 31, Issue 2, American Geophysical Union (AGU), Online.

   Online Links:

   • https://doi.org/10.1002/2015PA002847

   Other_Citation_Details: Pages 330-344
   

   Cheng, Hai, Edwards, R. Lawrence, Shen, Chuan-Chou, Polyak, Victor J., Asmerom, Yemane, Woodhead, Jon, Hellstrom, John, Wang, Yongjin, Kong, Xinggong, Spötl, Christoph, Wang, Xianfeng, and Alexander, E. Calvin Jr., 20130623, Improvements in 230Th dating, 230Th and 234U half-life values, and U–Th isotopic measurements by multi-collector inductively coupled plasma mass spectrometry: Earth and Planetary Science Letters Volumes 371-372, Elsevier, Online.

   Online Links:

   • https://doi.org/10.1016/j.epsl.2013.04.006

   Other_Citation_Details: Pages 82-91
   

   Toth, Lauren T., Stathakopoulos, Anastasios, and Kuffner, Ilsa B., 20180426, Descriptive core logs, core photographs, radiocarbon ages, and accretion data from Holocene reef cores collected throughout the Florida Keys reef tract: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL.

   Online Links:

   • https://doi.org/10.5066/F7NV9HJX

   Toth, Lauren T., and Stathakopoulos, Anastasios, 20190521, The absolute and relative composition of Holocene reef cores from the Florida Keys reef tract: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL.

   Online Links:

   • https://doi.org/10.5066/P93XXXA0

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

1. How well have the observations been checked?
   No formal attribute accuracy tests were conducted.
2. How accurate are the geographic locations?
   For more information about the horizontal positional accuracy for each coral reef core used in this study, please refer to the original collection using the CMGDS FAN page for a core’s given field activity. To view a particular field activity, replace the FAN (1976-300-FA) in the following url: https://cmgds.marine.usgs.gov/fan_info.php?fan=1976-300-FA. FANs are listed for each sample/core in the center'’s geologic core and sample database (Williams and others, 2013).
3. How accurate are the heights or depths?
   Sample elevations were determined by combining reported water depths with estimated depths downcore. For cores for which water depth was determined in the field with underwater depth gauges, a water depth uncertainty of 0.5 meter (m) was assigned. For four cores (LK-MG-2, LK-MG-3, UK-GR-3, and UK-GR-4), there were disagreements in the recorded water depth between field notes, notes on the core box, and/or previous publications describing the cores. As a result, a conservatively high 1 m water depth uncertainty was assigned. The elevations of two other cores (LK-WS-3 and UK-CR-2) were surveyed with high-precision Global Positioning System (GPS) equipment in the field, so benchmark uncertainties (0.004 and 0.015 m) were assigned in place of the water depth uncertainty. The tidal uncertainty was estimated as one-half the total tidal range reported for the nearest tidal datum, except for the three cores that were surveyed with GPS, for which it was assumed that there was no tidal uncertainty. To account for the fact that it is not possible to determine the exact position of a sample within a recovered interval of a core (i.e., the material in the interval can shift either during or after coring), the “sampling depth uncertainty” was estimated as one-half the porosity of that interval (i.e., 1-proportional recovery). A non-vertical drilling uncertainty, estimated as 0.02 m per m of core penetration, and a sample thickness uncertainty of 0.005 or one-half the estimated sample thickness of 0.01, were also included. These uncertainties were combined by root-sum-square to estimate a total elevation uncertainty for each sample.
4. Where are the gaps in the data? What is missing?
   The data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   No formal logical accuracy tests were conducted.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

   Attn: USGS SPCMSC Data Management

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8000 (voice)

   gs-g-spcmsc_data_inquiries@usgs.gov
2. What's the catalog number I need to order this data set? Late_Pleistocene_coral_data_from_south_Florida_and_uncertainties.csv, Late_Pleistocene_coral_data_from_south_Florida_and_uncertainties.xlsx
3. What legal disclaimers am I supposed to read?
   Although these data have been processed successfully on a computer system at 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. The USGS shall not be held liable for improper or incorrect use of the data described or contained herein. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	comma-delimited text, Microsoft Excel format
     Network links:	https://coastal.er.usgs.gov/data-release/doi-P9EJBYKZ/data/Late_Pleistocene_coral_data_from_south_Florida.zip

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 25-Jul-2024

Metadata author:

U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

Attn: USGS SPCMSC Data Management

600 4th Street South

Saint Petersburg, FL

United States

727-502-8000 (voice)

gs-g-spcmsc_data_inquiries@usgs.gov

Metadata standard:

FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata (FGDC-STD-001.1-1999)