Mark W. Carter
Ryan J. McAleer
Chris S. Holm-Denoma
Marci E. Occhi
Brent E. Owens
Jorge A. Vazquez
20230126
Whole Rock Geochemistry and Uranium Lead Isotopic Data from the Dinwiddie Terrane, Virginia, USA
spreadsheet
https://doi.org/10.5066/P92IZPID
This data release includes whole rock geochemical data, and uranium-lead isotopic data collected by both Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and Sensitive High Resolution Ion Microprobe-Reverse Geometry (SHRIMP-RG) methods. Whole rock geochemistry was collected by Activation Laboratories in Ancaster, Ontario. LA-ICP-MS data was collected at the PLASMA at the USGS in Denver, Colorado. SHRIMP-RG data was collected at the USGS-Stanford SHRIMP-RG in Palo Alto, California. Rock samples for all methods were collected by Mark Carter of the USGS. The whole rock geochemistry and uranium lead isotopic data constrain the age and origin of rocks in the newly defined Dinwiddie Terrane of eastern Virginia.
The data were collected in support of geologic mapping of the Piedmont of eastern Virginia. The data constrain the age and origin of rocks in the newly defined Dinwiddie Terrane. This data release accompanies the planned publication, Redefinition of the Petersburg batholith and implications of crustal inheritance in the Dinwiddie terrane, Virginia, USA, submitted to the journal Geosphere.
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
2017
2022
ground condition
None planned
Virginia Piedmont
-78.0000
-77.0000
38.0000
36.7500
ISO 19115 Topic Category
biota
None
U.S. Geological Survey
USGS
Florence Bascom Geoscience Center
FBGC
National Cooperative Geologic Mapping Program
NGCMP
Piedmont
U/Pb
Geochronology
Geochemistry
LA-ICP-MS
SHRIMP-RG
USGS Metadata Identifier
USGS:634fecbcd34e47431c15bad8
None
Virginia
Piedmont
Richmond
James River
None. Please see 'Distribution Info' for details.
None. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations.
Ryan McAleer
U.S. Geological Survey, Northeast Region
Research Geologist
mailing address
Mail Stop 926A, 12201 Sunrise Valley Dr
Reston
VA
20192
US
703-648-6052
703-648-6953
rmcaleer@usgs.gov
These data have been peer reviewed and compared with related ancillary data.
Data were reviewed for consistency and analyses/results were checked for validity and fidelity of relationships.
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. All data as part of this collection were included in this data release for the region and time period specified in this metadata.
No formal positional accuracy tests were conducted
No formal positional accuracy tests were conducted
Zircon grains from 6 samples were dated by Sensitive High Resolution Ion Microprobe- Reverse Geometry (SHRIMP-RG) methods using the following procedures:
Samples were collected from the field by Mark Carter of U.S. Geological Survey, Florence Bascom Geoscience Center, Reston, Virginia.
Zircon grains were extracted from six, approximately 5-10 kilogram samples at the USGS in Reston, Virginia. Samples were crushed and ground in a Sturtevant jaw crusher and Bico direct-drive disk mill, respectively, and then sieved to less than 250 μm (60 mesh). Particles larger than 250 μm were given a second pass through the disk mill. The fraction smaller than 250 μm was then passed over a Wilfley table to concentrate heavy minerals. For samples with abundant heavy minerals, the heavy fraction was sent over the Wilfley table a second time to reduce the volume for further processing. The heavy minerals were dried immediately on a hotplate. Following removal of the most magnetic material with a hand magnet, the sample was sent through a Frantz L1 magnetic separator and lithium heteropolytungstate (LST) heavy liquid (ρ=2.85 grams per cubic centimeter [g/cm3]) to further concentrate zircon. The order of these two steps varied depending on the mineral assemblage of the sample. The nonmagnetic fraction heavier than LST was then put through methylene iodide (ρ=3.3 g/cm3) to produce a final concentrate. Zircons were hand-picked from the this concentrate under incident and transmitted light using a Leica Z16 binocular microscope.
Selected zircon grains were mounted on double-sided kapton tape and fixed with Struers EpoFix epoxy in a 1-inch round cylinder. The resulting 1-inch round mount was polished with 2500-grit wet-dry sandpaper and polished sequentially on a Struers LaboPol polisher using 6 µm and 1 µm diamond suspensions to expose internal textural features with a goal of polishing halfway into the grains.
Prior to isotopic analysis, all grains were simultaneously imaged in backscattered electron (BSE) and panchromatic cathodoluminescence (CL) modes using a Hitachi SU-5000 FE-SEM scanning electron microscope at the USGS in Reston, Virginia. The panchromatic CL images were obtained using a Hitachi UVD detector with the bias turned off. Following SHRIMP-RG isotopic analysis the analyzed grains were re-imaged using a Delmic-Sparc CL detector fitted to the SU-5000 to confirm analysis locations using high-resolution CL imagery (Figure 11).
Zircon grains from the six samples were analyzed by secondary ionization mass spectrometry on the U.S. Geological Survey (USGS)/Stanford sensitive high-resolution ion microprobe-reverse geometry (SHRIMP-RG) during three separate analytical sessions in 2018 and 2019. Sample DW-11 was analyzed in October of 2018; M19-02-28A, M19-02-28B, and M19-02-28C were analyzed in June of 2019; and samples JR-1-1 and Jack-1 were analyzed in October 2019. A similar analytical setup was used in each session and measured 9 peak locations in 5 cycles on the single collector SHRIMP-RG. The spot size for all analyses was approximately 20 μm in diameter and approximately 1 μm in depth, and the primary beam was ~3 to 6 nA. Zircon standard R33 (419 Ma; Black et al., 2004) mounted with the unknowns was used to correct 206Pb/238U ages for elemental fractionation and was run after every fourth unknown analysis. Raw data were reduced using Squid 2 (Ludwig, 2009) and plotted using Isoplot 3.75 and IsoplotR (Ludwig, 2012, Versmeech, 2018). Calculated 206Pb/238U ages for these Paleozoic aged samples are reported at 2σ and are weighted average ages; these data are shown in Table 3. Spot ages were considered concordant if the 2σ error ellipse overlapped concordia on a Wetherhill plot (Spencer et al., 2016). Uncertainties on single spot analyses, when stated, are at 2σ. Analytical isotopic data for individual spot analyses are given in Table 4. U and Th concentrations are also reported for each analysis and are relative to analyses of the concentration standard MAD-559 (3940 ppm U, 483 ppm Th; Coble et al., 2018) that was mounted with each set of unknowns.
Coble, M.A., Vazquez, J.A., Barth, A.P., Wooden, J., Burns, D., Kylander‐Clark, A., Jackson, S. and Vennari, C.E., 2018, Trace element characterization of MAD‐559 zircon reference material for ion microprobe analysis: Geostandards and Geoanalytical Research, v. 42, n. 4, p.481-497.
Ludwig, K.R., 2009, SQUID 2, A user’s manual (rev 2.50): Berkeley Geochronology Center Special Publication 5, 110 p., accessed September 2019 at http://bgc.org/isoplot_etc/squid/SQUID2_5Manual.pdf.
Ludwig, K.R., 2012, User’s manual for Isoplot 3.75—A geo¬chronological toolkit for Microsoft Excel: Berkeley Geo¬chronology Center Special Publication 5, 75 p., accessed September 2019 at http://www.bgc.org/isoplot_etc/isoplot/Isoplot3_75-4_15manual.pdf.
Spencer, C.J., Kirkland, C.L., and Taylor, R.J., 2016, Strate¬gies towards statistically robust interpretations of in situ U–Pb zircon geochronology: Geoscience Frontiers, v. 7, no. 4, p. 581–589, accessed September 2019 at https://doi.org/10.1016/j.gsf.2015.11.006.
Vermeesch, P., 2018, IsoplotR: a free and open toolbox for geochronology. Geoscience Frontiers, v.9, p.1479-1493, doi: 10.1016/j.gsf.2018.04.001.
2019
Zircon grains from 2 samples were dated by Laser Ablation Inductively Coupled Plasma Mass Spectrometery (LA-ICP-MS) methods using the following procedures:
Samples were collected from the field by Mark Carter of U.S. Geological Survey, Florence Bascom Geoscience Center, Reston, Virginia.
Zircon was concentrated from samples for LA-ICP-MS analyses using standard mineral separation methods (crushing, sieving, water density separation, magnetic separation, and heavy liquids) as detailed in Strong and Driscoll (2016). Zircon was mounted in epoxy, ground to approximately half thickness of the grains, and polished prior to cathodoluminescence (CL) imaging using a JEOL 5800 LV Scanning Electron Microscope (SEM).
For detrital zircon geochronology analyses (e.g., sample BonAirRRTracks), zircon was ablated with a Teledyne-Photon Machines Excite 193 nanometer argon-fluoride (ArF) excimer laser in spot mode. The laser spot sizes for zircon were approximately 25 micrometers (μm). Each analysis consisted of 150 total bursts with a repetition rate of 5 hertz, laser energy of approximately 3 millijoules, and an energy density of 4.11 joules per square centimeter. Pit depths are typically less than 10 μm. The rate of helium carrier gas flow from the HelEx cell of the laser was ~0.6 liters per minute (L/min). Make-up argon gas (approximately 0.6 L/min) was added to the sample stream prior to its introduction into the plasma. Nitrogen with flow rate of 5.5 milliliters per minute was added to the sample stream to allow for significant reduction in ThO+/Th+ (<0.5 percent) and improved the ionization of refractory Th (Hu et al., 2008). With the magnet centered at a constant mass, the flat tops of the isotope peaks of 202Hg, 204(Hg+Pb), 206Pb, 207Pb, 208Pb, 232Th, 235U, and 238U were measured by rapidly deflecting the ion beam with a 30-second on-peak background measured prior to each 30-second analysis. Raw data were reduced off-line using the Iolite 2.5 program (Paton et al., 2011) to subtract on-peak background signals, correct for U-Pb downhole fractionation, and normalize the instrumental mass bias using external mineral reference materials, the ages of which had previously been determined by isotope dilution-thermal ionization mass spectrometry. Ages were corrected by standard sample bracketing with the primary zircon reference material Temora2 (417 Ma; Black et al., 2004) and secondary reference materials FC-1 (1099 Ma; Paces and Miller, 1993) and Plešovice (337 Ma, Sláma et al., 2008). Raw data are shown in Table 2. For detrital zircon samples, reduced data was compiled into probability density plots using Isoplot 4.15 (Ludwig, 2012). 206Pb/238U ages are reported for zircons younger than approximately 1300 Ma and 207Pb/206Pb ages are used for older zircons following the recommendations of Gehrels (2012). Analyses that were greater than 10% discordant or more than 5% reverse discordant (206Pb/238U vs 207Pb/206Pb) were excluded from interpretive analyses.
For igneous rock samples (e.g., VDGMR Sample R-11518; foliated metagranitoid), 30 spot analyses (25 μm) were conducted on zircon grains (after extraction, selection and mounting). Spot analyses were selected based on zoning relationships determined in scanning electron microscope (SEM)-cathodoluminescence (CL; imaging conducted at the USGS Microbeam facility in Denver, Colorado). Spots were selected based on zoning relationships determined in SEM imaging. Core and rim relationships were determined in several of the zircons analyzed. In some cases, both zircon cores and rims from the same zircon grain were analyzed to compare ages. Zircon analyses from this sample that were greater than 5% discordant or reverse discordant (207Pb/235U vs 206Pb/238U) were excluded from interpretive analyses. Additionally, analyses that had U/Th ratios greater than 5 were excluded from interpretive analyses due to the possibility that they are metamorphic overgrowths. Raw data reduction was completed using Iolite v.2.5 (Paton et al., 2011). Reduced data were then interpreted using the Excel macro Isoplot v. 4.15 (Ludwig, 2012).
Black, L.P., Kamo, S.L., Allen, C.M., Davis, D.W., Aleinikoff, J.N., Valley, J.W., Mundil, R., Campbell, I.H., Korsch, R.J., Williams, I.S., Foudoulis, C., 2004, Improved 206Pb/238U microprobe geochronology by the monitoring of a trace-element-related matrix effect; SHRIMP, ID–TIMS, ELA–ICP–MS and oxygen isotope documentation for a series of zircon standards: Chemical Geology, v. 205, is. 1-2, pg. 115-140, available at https://doi.org/10.1016/j.chemgeo.2004.01.003.
Mattinson, James M., 2010, Analysis of the relative decay constants of 235U and 238U by multi-step CA-TIMS measurements of closed-system natural zircon samples: Chemical Geology, v. 275, pg. 186-198, available at https://doi.org/10.1016/j.chemgeo.2010.05.007.
Paton, C., Hellstrom, J., Paul, B., Woodhead, J., Hergt, J., 2011, Iolite: Freeware for the visualisation and processing of mass spectrometric data: Journal of Analytical Atomic Spectrometry, v. 26, pg. 2508-2518, available at https://doi.org/10.1039/C1JA10172B
Slama, J., Kosler, J., Condon, D.J., Crowley, J.L., Gerdes, A., Hanchar, J.M., Horstwood, M.S.A., Morris, G.A., Nasdala, L., Norberg, N., Schaltegger, U., Schoene, B., Tubrett, M.N., Whitehouse, M.J., 2008, Plesovice zircon-A new natural reference material for U-Pb and Hf isotopic microanalysis: Chemical Geology, v. 249, is. 1-2, pg. 1-35, available at https://doi.org/10.1016/j.chemgeo.2007.11.005.
2019
USGS-funded whole rock analyses of major and trace elements were obtained on 23 samples at Activation Laboratories (ActLabs) in Ancaster, Ontario, the USGS contract laboratory. The following procedures were used:
Samples were collected from the field by Mark Carter of U.S. Geological Survey, Florence Bascom Geoscience Center, Reston, Virginia and shipped to ActLabs.
A combination of Actlabs procedures 4B, 4B1 and 4B2 were used to determine major and trace element compositions. The methods and elements analyzed are summarized below.
Samples fused under method 4B are prepared and analyzed in a batch system. Each batch contains a method reagent blank, certified reference material and 6% replicates. Samples are mixed with a flux of lithium metaborate and lithium tetraborate and fused in an induction furnace. The molten melt is immediately poured into a solution of 5% nitric acid containing an internal standard, and mixed continuously until completely dissolved. The samples are run for major oxides and selected trace elements by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Elements and oxides analyzed are Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2, TiO2, Ba, Be, Sc, Sr, V, Zr.
Samples fused under code 4B2 are diluted and analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Three blanks and five controls (three before the sample group and two after) are analyzed per group of samples. Duplicates are fused and analyzed every 15 samples. Instrument is recalibrated every 40 samples. Elements Ag, As, Bi, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Ga, Gd, Ge, Hf, Ho, In, La, Lu, Mo, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sm, Sn, Sr, Ta, Tb, Th, Tl, Tm, U, W, Y, Yb, Zn were determined by this method.
For sample analysis under code 4B1 a 0.25 g sample is digested with four acids beginning with hydrofluoric, followed by a mixture of nitric and perchloric acids, heated using precise programmer controlled heating in several ramping and holding cycles which takes the samples to dryness. After dryness is attained, samples are brought back into solution using hydrochloric acid and analyzed by ICP-OES. This method was used to determine Ag, Cd, Cu, Ni, Pb, S, and Zn.
2019
Dinwiddie_WR_Data.csv
Comma Separated Value (CSV) file containing data.
Producer defined
SampleID
Sample identifier assigned in the field by the collector.
Producer defined
<< empty cell >>
No Data
Producer defined
Sample identifier assigned in the field by the collector.
Latitude
Latitude; in decimal degrees; referenced to the World Geodetic System 1984 (WGS84)
Producer defined
<< empty cell >>
No Data
Producer defined
36.9562
37.6985
Longitude
Longitude; in decimal degrees; referenced to the World Geodetic Datum 1984 (WGS84).
Producer defined
<< empty cell >>
No Data
Producer defined
-77.6461
-77.4535
Quadrangle
Topographic map sheet where the sample is from.
Producer defined
<< empty cell >>
No Data
Producer defined
Bon Air
Quadrangle name
Producer defined
De Witt
Quadrangle name
Producer defined
Sutherland
Quadrangle name
Producer defined
Chesterfield
Quadrangle name
Producer defined
Glen Allen
Quadrangle name
Producer defined
Yellow Tavern
Quadrangle name
Producer defined
Richmond
Quadrangle name
Producer defined
Cherry Hill
Quadrangle name
Producer defined
Bedrock_Lithology
Sample lithology assigned in the field by the collector.
Producer defined
<< empty cell >>
No Data
Producer defined
aplite
Rock type
Producer defined
blue quartz-bearing granitoid
Rock type
Producer defined
coarse-grained massive granite
Rock type
Producer defined
massive granite
Rock type
Producer defined
subidiomorphic granite
Rock type
Producer defined
subidiomorphic granite
Rock type
Producer defined
porphyritic granite
Rock type
Producer defined
foliated porphyritic granite
Rock type
Producer defined
coarse-layered granitiod gneiss
Rock type
Producer defined
foliated granite
Rock type
Producer defined
foliated granite, with distinct foliation defined by both muscovite and biotite
Rock type
Producer defined
medium-grained moderately to strongly foliated biotite-granitoid
Rock type
Producer defined
moderately to strongly-foliated medium grained biotite granitoid
Rock type
Producer defined
strongly foliated granite
Rock type
Producer defined
strongly-foliated medium grained biotite granitoid
Rock type
Producer defined
medium-grained weakly foliated garnet-bearing biotite-granitoid
Rock type
Producer defined
staurolite-mica schist
Rock type
Producer defined
SiO2
Silicon oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
59.3
76.49
Al2O3
Aluminum oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
12.74
24.43
Fe2O3
Ferric iron oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.77
6.86
MnO
Manganese oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.014
0.355
MgO
Magnesium oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.05
2.1
CaO
Calcium oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.1
3.5
Na2O
Sodium oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.55
4.56
K2O
potassium oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2.01
6.89
TiO2
Titanium oxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.052
1.103
P2O5
Phosphate pentoxide, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.01
0.27
LOI
Loss on ignition, in weight percent, by gravimetric difference. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.39
4.18
Total
Total, in weight percent, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
98.48
100.85
Ag
Silver, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.3
0.7
As
Arsenic, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-5
90
Ba
Barium, in parts per million, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
99
1091
Be
Beryllium, in parts per million, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2
15
Bi
Bismuth, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.1
4.9
Cd
Cadmium, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.5
-0.5
Co
Cobalt, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-1
11
Cr
Chromium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-20
140
Cs
Cesium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2.7
13.0
Cu
Copper, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-1
100
Ga
Gallium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
11
42
Ge
Germanium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
1.1
3.7
Hf
Hafnium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
1.9
7.0
In
Indium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.1
0.2
Mo
Molybdenum, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-2
6
Nb
Niobium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
4.2
22.5
Ni
Nickel, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-1
15
Pb
Lead, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
11
61
Rb
Rubidium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
141
347
S
Sulfur, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
30
90
Sb
Antimony, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.2
1.6
Sc
Scandium, in parts per million, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2
17
Sn
Tin, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
1
11
Sr
Strontium, in parts per million, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
39
405
Ta
Tantalum, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.69
4.69
Th
Thorium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
7.21
58.8
U
Uranium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2.52
20.5
V
Vanadium, in parts per million, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
8
114
W
Tungsten, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
-0.5
12.4
Y
Yttrium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
8.1
58.0
Zn
Zinc, in parts per million, by ICP after total digestion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
9
450
Zr
Zirconium, in parts per million, by ICP-OES after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
33
243
La
Lanthanum, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
5.5
132.0
Ce
Cerium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
12.1
266.0
Pr
Praseodymium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
1.49
29.4
Nd
Neodymium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
5.9
103.0
Sm
Samarium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
1.87
22.1
Eu
Europium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.311
4.28
Gd
Gadolinium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2.21
16.9
Tb
Terbium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.35
2.76
Dy
Dysprosium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
2.03
13.8
Ho
Holmium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.31
2.38
Er
Erbium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.77
6.4
Tl
Thallium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.78
1.79
Tm
Thulium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.111
1.36
Yb
Ytterbium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.75
12.0
Lu
Lutetium, in parts per million, by ICP-MS after fusion. Negative values indicate determinations less than the detection limit of the analytical method. The absolute value of the negative number is the detection limit.
Producer defined
<< empty cell >>
No Data
Producer defined
0.111
2.11
Unnamed: 64
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Dinwiddie_SHRIMPSummary.csv
Comma Separated Value (CSV) file containing data.
Producer defined
Sample_ID
Collector's sample name (often field name/number)
Producer defined
<< empty cell >>
No Data
Producer defined
DW-11
Sample name
Producer defined
Jack-1
Sample name
Producer defined
M19-02-28B
Sample name
Producer defined
M19-02-28C
Sample name
Producer defined
JR-1
Sample name
Producer defined
M19-02-28A
Sample name
Producer defined
FieldName
Taxonomy (field name) Informal classification of sample, for example, dacite
Producer defined
<< empty cell >>
No Data
Producer defined
blue quartz-bearing granitoid
rock type
Producer defined
coarse-grained massive granite
rock type
Producer defined
medium-grained moderately to strongly foliated biotite-granitoid
rock type
Producer defined
moderately to strongly-foliated medium grained biotite granitoid
rock type
Producer defined
strongly foliated granite
rock type
Producer defined
medium-grained weakly foliated garnet-bearing biotite-granitoid
rock type
Producer defined
SampleType
Describes the type of sample
Producer defined
<< empty cell >>
No Data
Producer defined
Individual Sample
Individual Sample
Producer defined
Material
Material of which the sample consists
Producer defined
<< empty cell >>
No Data
Producer defined
Rock
A rock, rather than sediment or single grains.
Producer defined
RockClass
Formal categorization of sample
Producer defined
<< empty cell >>
No Data
Producer defined
Igneous>Plutonic>Felsic
Rock classification
Producer defined
Lat
Latitude of the location where the sample was collected, entered in decimal degrees Negative values for South latitudes
Producer defined
<< empty cell >>
No Data
Producer defined
37.0781
37.6985
Long
Longitude of the location where the sample was collected, entered in decimal degrees Negative values for West longitudes
Producer defined
<< empty cell >>
No Data
Producer defined
-77.6461
-77.4535
GeoDatum
Geodetic datum for the sample coordinates
Producer defined
<< empty cell >>
No Data
Producer defined
unknown
datum unknown
Producer defined
Locality
Name of the specific place where the sample was collected
Producer defined
<< empty cell >>
No Data
Producer defined
Virginia Piedmont
Physiographic province in Virginia.
Producer defined
Country
Country where the sample was collected
Producer defined
<< empty cell >>
No Data
Producer defined
United States
United States
Producer defined
StateProvince
State or province where the sample was collected
Producer defined
<< empty cell >>
No Data
Producer defined
Virginia
Virginia
Producer defined
SampleMaterial
Material anlayzed.
Producer defined
<< empty cell >>
No Data
Producer defined
zircon
the mineral zircon
Producer defined
Age_text
Best age estimate provided by the authors.
Producer defined
<< empty cell >>
No Data
Producer defined
320.5 Ma
Age
Producer defined
317.3 Ma
Age
Producer defined
424.6 Ma
Age
Producer defined
324.4 Ma
Age
Producer defined
418.1 Ma
Age
Producer defined
403.0 Ma
Age
Producer defined
299 Ma
Age
Producer defined
404 Ma
Age
Producer defined
308.0 Ma
Age
Producer defined
AgeUnc_text
Two sigma uncertainty on interpreted age.
Producer defined
<< empty cell >>
No Data
Producer defined
3.5 Ma
Age uncertainty
Producer defined
3.6 Ma
Age uncertainty
Producer defined
3.2 Ma
Age uncertainty
Producer defined
2.6 Ma
Age uncertainty
Producer defined
3.8 Ma
Age uncertainty
Producer defined
14 Ma
Age uncertainty
Producer defined
7 Ma
Age uncertainty
Producer defined
4.1 Ma
Age uncertainty
Producer defined
AgeIntpnType
Method used to calculate age
Producer defined
<< empty cell >>
No Data
Producer defined
Weighted Average
Weighted Average
Producer defined
AgeIntpnClass
Interpreted age classification of a sample (crystallization age, eruption age, sedimentation age, etc.)
Producer defined
<< empty cell >>
No Data
Producer defined
crystallization age
Age mineral crystallized from melt
Producer defined
metamorphic age
Age mineral grew from metamorphic fluid
Producer defined
AgeComment
Comments on age.
Producer defined
<< empty cell >>
No Data
Producer defined
207Pb corrected 206Pb/238U age, n = 13
Age type and number of analyses (n).
Producer defined
207Pb corrected 206Pb/238U age, n = 19
Age type and number of analyses (n).
Producer defined
207Pb corrected 206Pb/238U age,, n = 13
Age type and number of analyses (n).
Producer defined
207Pb corrected 206Pb/238U age, n = 7
Age type and number of analyses (n).
Producer defined
207Pb corrected 206Pb/238U age, n = 6
Age type and number of analyses (n).
Producer defined
207Pb corrected 206Pb/238U age, n = 5
Age type and number of analyses (n).
Producer defined
207Pb corrected 206Pb/238U age, n = 4
Age type and number of analyses (n).
Producer defined
Lab
Laboratory name
Producer defined
<< empty cell >>
No Data
Producer defined
Stanford University-USGS SHRIMP-RG Lab
Sensitive High Resolution Ion Microprobe, Reverse-Geometry.
Producer defined
InstrumentMethod
Type of instrumental analysis
Producer defined
<< empty cell >>
No Data
Producer defined
SIMS (Ion Microprobe)
Secondary Ionization Mass Spectrometry
Producer defined
Citation
Citation for the original data source
Producer defined
<< empty cell >>
No Data
Producer defined
Carter, M.W., McAleer, R.J., Holm-Denoma, C,.S., Occhi, M.E., Owens, B.E, and Vazquez, J.A., 2022. Whole Rock Geochemistry and Uranium Lead Isotopic Data from the Dinwiddie Terrane, Virginia, USA: U.S. Geological Survey Data Release
citation
Producer defined
URL
Link, either an online URL or Digital Object Identifier (DOI) to the data source or a full description of the data source
Producer defined
<< empty cell >>
No Data
Producer defined
https://doi.org/10.5066/P92IZPID
url
Producer defined
PeerReviewed
Has this data source been peer-reviewed (Y/N)?
Producer defined
<< empty cell >>
No Data
Producer defined
Yes
yes the data were peer reviewed
Producer defined
Compiler
Name of person who compiled data into database (your name here!)
Producer defined
<< empty cell >>
No Data
Producer defined
McAleer, R.J.
Ryan J. McAleer
Producer defined
LocPrecType
Source of location information includes whether publication lists coordinates or if coordinates have been georeferenced from a field map
Producer defined
<< empty cell >>
No Data
Producer defined
given coordinates
coordinates of sample
Producer defined
Collection
Identification of the original source of the set of information associated with a set of samples
Producer defined
<< empty cell >>
No Data
Producer defined
not part of a collection
sample was not part of a collection
Producer defined
CollectionMethod
Method of collection
Producer defined
<< empty cell >>
No Data
Producer defined
single sample
a single sample was collected
Producer defined
SampleSrc
Sample source
Producer defined
<< empty cell >>
No Data
Producer defined
unknown
unknown sample source
Producer defined
LocPrecComment
Comments about location precision
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
LocPrec
Location precision in meters
Producer defined
<< empty cell >>
No Data
Producer defined
-9999
-9999
Dinwiddie_SHRIMPData.csv
Comma Separated Value (CSV) file containing data.
Producer defined
Sample_ID
Collector's sample name (often field name/number)
Producer defined
<< empty cell >>
No Data
Producer defined
DW-11
Sample name
Producer defined
JR-1
Sample name
Producer defined
Jack-1
Sample name
Producer defined
M19-02-28C
Sample name
Producer defined
M19-02-28A
Sample name
Producer defined
M19-02-28B
Sample name
Producer defined
Analysis_ID
Laboratory run identifier assigned by analyst
Producer defined
<< empty cell >>
No Data
Producer defined
Laboratory run identifier assigned by analyst
PctCommon206Pb
common 206Pb, in percent
Producer defined
<< empty cell >>
No Data
Producer defined
-0.252
69.171
U
Concentration of Uranium (U) in parts per million
Producer defined
<< empty cell >>
No Data
Producer defined
85
4705
Th
Concentration of Thorium (Th) in parts per million
Producer defined
<< empty cell >>
No Data
Producer defined
5
886
Th232U238
Ratio of 232Th to 238U
Producer defined
<< empty cell >>
No Data
Producer defined
0.0
1.5
Pb207CorrPb206U238Age
Final 207 corrected 206Pb/238U Age in Mega annum (Ma)
Producer defined
<< empty cell >>
No Data
Producer defined
85.0
631.0
Pb207CorrPb206U238AgeUnc
One sigma uncertainty (absolute) for final 207 corrected 206Pb/238U age in Mega annum (Ma)
Producer defined
<< empty cell >>
No Data
Producer defined
1
284
Pb204CorrPb207Pb206Age
Final 204Pb corrected 207Pb/206Pb Age in Mega annum (Ma)
Producer defined
<< empty cell >>
No Data
Producer defined
Final 204Pb corrected 207Pb/206Pb Age in Mega annum (Ma)
Pb204CorrPb207Pb206AgeUnc1S
One sigma uncertainty (absolute) for final 204Pb corrected 207Pb/206Pb in Mega annum (Ma)
Producer defined
<< empty cell >>
No Data
Producer defined
One sigma uncertainty (absolute) for final 204Pb corrected 207Pb/206Pb in Mega annum (Ma)
PctDiscordW
Percent discordance relative to 206Pb/238U age vs 207Pb/235U age
Producer defined
<< empty cell >>
No Data
Producer defined
-18491
49
Pb204CorrU238Pb206
204Pb-corrected ratio of 238U/206Pb
Producer defined
<< empty cell >>
No Data
Producer defined
9.7
74.8
Pb204CorrU238Pb206Unc
One sigma uncertainty (percent) on 204Pb-corrected ratio of 238U/206Pb
Producer defined
<< empty cell >>
No Data
Producer defined
0.6
58.5
Pb204CorrPb207Pb206
204Pb-corrected ratio of 207Pb/206Pb
Producer defined
<< empty cell >>
No Data
Producer defined
0.0002
0.1499
Pb204CorrPb207Pb206Unc
One sigma uncertainty (percent) on 204Pb-corrected ratio of 207Pb/206Pb
Producer defined
<< empty cell >>
No Data
Producer defined
0.5
8416.1
Pb204CorrPb207U235
204Pb-corrected ratio of 207Pb/235U
Producer defined
<< empty cell >>
No Data
Producer defined
0.002
1.7
Pb204CorrPb207U235Unc
One sigma uncertainty (percent) on 204Pb-corrected ratio of 207Pb/235U
Producer defined
<< empty cell >>
No Data
Producer defined
1.2
8416.1
Pb204CorrPb206U238
204Pb-corrected ratio of 206Pb/238U
Producer defined
<< empty cell >>
No Data
Producer defined
0.0134
0.1027
Pb204CorrPb206U238Unc
One sigma uncertainty (percent) on 204Pb-corrected ratio of 206Pb/238U
Producer defined
<< empty cell >>
No Data
Producer defined
0.6
58.5
RHOWetherill
Correlation coefficient between 206Pb/238U and 207Pb/235U
Producer defined
<< empty cell >>
No Data
Producer defined
0.0
0.98
AgeIntpnType
Method used to calculate age
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
AgeIntpnClass
Interpreted age classification of a sample (crystallization age, eruption age, sedimentation age, etc.)
Producer defined
<< empty cell >>
No Data
Producer defined
no interpretation
no interpreted age classification for this analysis
Producer defined
InclAnalysisAgeCalc
Analysis included in interpreted age calculation (Yes = 1 or No = 0)
Producer defined
<< empty cell >>
No Data
Producer defined
Not Specified
none
Producer defined
DomainAnalyzed
Domain analyzed (core/rim/whole)
Producer defined
<< empty cell >>
No Data
Producer defined
rim
Rim domain analyzed as identified by backscatter electron and/or cathodoluminescence imaging.
Producer defined
core
Core domain analyzed as identified by backscatter electron and/or cathodoluminescence imaging.
Producer defined
fracture fill
Fracture fill domain, identified by backscatter electron and/or cathodoluminescence imaging., analyzed.
Producer defined
inherited core
Inherited core domain analyzed as identified by backscatter electron and/or cathodoluminescence imaging.
Producer defined
metamict
Metamict domain analyzed as identified by backscatter electron and/or cathodoluminescence imaging.
Producer defined
SampleMaterial
Mineral or rock sampled for analysis.
Producer defined
<< empty cell >>
No Data
Producer defined
zircon
The mineral zircon.
Producer defined
AnalysisType
Analysis type - Single crystal, multi crystal, bulk, groundmass,
Producer defined
<< empty cell >>
No Data
Producer defined
Spot
Spot analysis within a single grain.
Producer defined
Lab
Laboratory name
Producer defined
<< empty cell >>
No Data
Producer defined
Stanford University-USGS SHRIMP-RG Lab
Sensitive High Resolution Ion Microprobe-Reverse Geometry.
Producer defined
InstrumentMethod
Type of instrumental analysis
Producer defined
<< empty cell >>
No Data
Producer defined
SIMS (Ion Microprobe)
Secondary Ionization Mass Spectrometry
Producer defined
Unnamed: 28
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Unnamed: 29
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Unnamed: 30
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Unnamed: 31
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Unnamed: 32
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Unnamed: 33
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Unnamed: 34
empty column
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
Dinwiddie_LAICPMS_Data.csv
Comma Separated Value (CSV) file containing data.
Producer defined
Analysis
Analysis number with sample identifier
Producer defined
Source file
The TRA (time resolved analysis) number of the run for correlation with the standard values for the same run
Producer defined
8503_TRA_Analysis.csv
TIme resolved analysis number.
Producer defined
9034_TRA_Analysis.csv
TIme resolved analysis number.
Producer defined
9035_TRA_Analysis.csv
TIme resolved analysis number.
Producer defined
Date
The date the data was collected
Producer defined
11/10/2018 (5)
Date of analysis.
Producer defined
12/08/2019 (2)
Date of analysis.
Producer defined
Final207_235
Down hole corrected and sample-standard bracketed 207Pb/235U ratio.
Producer defined
0.405
5.6
Final207_235_Prop2SE
Two sigma standard error (absolute uncertainty) for final 207Pb/235U ratio.
Producer defined
0.011
0.19
Final206_238
Down hole corrected and sample-standard bracketed 206Pb/238U ratio.
Producer defined
0.0381
0.3206
Final206_238_Prop2SE
Two sigma standard error (absolute uncertainty) for final 206Pb/238U ratio.
Producer defined
0.0008
0.0046
ErrorCorrelation_6_38vs7_35
Correlation coefficient between 206Pb/238U and 207Pb/235U ratios.
Producer defined
0.001
0.96438
Final238_206
Down hole corrected and sample-standard bracketed 238U/206Pb ratio.
Producer defined
3.11915
26.24672
Final238_206_Prop2SE
Two sigma standard error (absolute uncertainty) for final 238U/206Pb ratio.
Producer defined
0.036
1.65334
Final207_206
Down hole corrected and sample-standard bracketed 207Pb/206Pb ratio.
Producer defined
0.0529
0.2901
Final207_206_Prop2SE
Two sigma standard error (absolute uncertainty) for final 207Pb/206Pb ratio.
Producer defined
0.001
0.013
ErrorCorrelation_38_6vs7_6
Correlation coefficient between 238U/206Pb and 207Pb/206Pb ratios.
Producer defined
-0.92049
0.76465
FinalAge206_238
206Pb/238U age calculated from down hole corrected and sample-standard bracketed ratio.
Producer defined
241.0
1793.0
FinalAge206_238_Prop2SE
Two sigma standard error (absolute uncertainty) for final 206Pb/238U age
Producer defined
5.0
28.0
FinalAge207_235
207Pb/235U age calculated from down hole corrected and sample-standard bracketed ratio.
Producer defined
345.3
1916.0
FinalAge207_235_Prop2SE
Two sigma standard error (absolute uncertainty) for final 207Pb/235U age
Producer defined
7.7
85.0
FinalAge207_206
207Pb/206Pb age calculated from down hole corrected and sample-standard bracketed ratio.
Producer defined
324
3425
FinalAge207_206_Prop2SE
Two sigma standard error (absolute uncertainty) for final 207Pb/206Pb age
Producer defined
28
280
Approx_U_PPM
U determined by LA-ICPMS in parts per million (ppm)
Producer defined
110.5
7630.0
Approx_Th_PPM
Th determined by LA-ICPMS in parts per million (ppm)
Producer defined
27.0
1114.0
Approx_Pb_PPM
Pb determined by LA-ICPMS in parts per million (ppm)
Producer defined
1.01
67.0
FInal_U_Th_Ratio
Calculated ratio of uranium concentration divided by thorium concentration
Producer defined
0.7
164.0
Perc_DISC
Percentage difference in 206Pb/238U and 207/206Pb ages if the preferred age is >500Ma, or percentage difference in 206Pb/238U and 207Pb/235U if the preferred age is less than 500 Ma
Producer defined
-27.0
74.5
Preferred Age
The preferred age for the analysis. If the 206Pb/238U age is less than 1300Ma, the 206Pb/238U age is preferred; if the 206Pb/238U age is >1300Ma, the 207Pb/206Pb age is preferred.
Producer defined
241.0
2045.0
Age_Prop2SE
Two sigma standard error (absolute uncertainty) for preferred age.
Producer defined
5.0
28.0
Dinwiddie_LAICPMS_Summary.csv
Comma Separated Value (CSV) file containing data.
Producer defined
Sample
The name of the sample
Producer defined
R-11518
Unique sample name.
Producer defined
BonAirRRTracks
Unique sample name.
Producer defined
Latitude
The latitude of the sample location, datum of WGS84
Producer defined
37.31916
37.52464
Longitude
The longitude of the sample location, datum of WGS84
Producer defined
-77.57693
-77.50386
Rock_class
The rock class from which the sample was collected.
Producer defined
Igneous
Rock type.
Producer defined
Metamorphic
Rock type.
Producer defined
Unnamed: 4
empty
Producer defined
<< empty cell >>
No Data
Producer defined
nan
nan
GS ScienceBase
U.S. Geological Survey
mailing address
Denver Federal Center, Building 810, Mail Stop 302
Denver
CO
80225
United States
1-888-275-8747
sciencebase@usgs.gov
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 for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty.
Digital Data
https://doi.org/10.5066/P92IZPID
None
20230126
Ryan McAleer
U.S. Geological Survey, Northeast Region
Research Geologist
mailing address
Mail Stop 926A, 12201 Sunrise Valley Dr
Reston
VA
20192
US
703-648-6052
703-648-6953
rmcaleer@usgs.gov
FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata
FGDC-STD-001.1-1999