B08_Attachment_C_Performance_Work_Statement.docx

Performance-Based Work Statement

I - General Information:

The Geology, Energy, and Minerals Science Center (GEMSC) has a need for clumped isotope geochemical analyses of carbonate mineral samples including but not limited to rocks, sediments, veins, or fossil specimens. These analyses will support GEMSC projects that study energy and minerals resources and the geologic processes that lead to their occurrence. GEMSC anticipates needing analyses to measure data in support of USGS studies to be published as data releases, USGS publications and peer reviewed scientific journal articles.

Scope: The purpose of this purchase request is to establish a five-year BPA contract not-to-exceed $49,000.00 with a laboratory with a proven history of measuring, in a timely and properly documented fashion, clumped isotope analyses and traditional stable carbon and oxygen isotope analyses that meet state-of-the-art analytical precision and follow community-accepted InterCarb standardization practices.

II - Work Requirements:

A - Technical Requirements:

1 - Carbonate mineral samples are expected to be measured for clumped isotopic compositions (D47 and D48) and/or stable carbon (d13C) and oxygen isotopic compositions (d18O) to determine the temperature and fluid isotopic composition at time of mineral precipitation and/or the thermal history of the sample. Preference will be given to laboratories that can measure small samples (<500µg carbonate mineral powder replicates) on instruments optimized for high precision clumped isotope analyses (for example, the Nu Perspective, ThermoFisher MAT253 Plus, or equivalent models) and equipped with peripheral units for semi-automated sample digestion and analysis (for example the Nu Carb, Kiel Carbonate Device, or equivalent models).

Laboratories should be capable of analyzing different carbonate minerals such as calcite or dolomite, and ideally magnesite samples. If laboratories do not have the analytical capability to measure magnesite samples for D47, then laboratory instruments should be equipped to measure CO2 gas samples from sealed glass ampules that the USGS may prepare from magnesite samples.

Clumped isotope samples must be measured alongside InterCarb ETH standards for data calibration. Samples must also be measured alongside “check standards” which could include in-house carbonate standards with established D47, D48, d18O, and d13C values. Data must be corrected for acid fractionation and reported in conformance with accepted InterCarb research community standards and practices. Values for D47 should be reported as standardized to the carbon dioxide equilibrium scale (I-CDES90). Temperature data should be reported based on accepted D47-temperature calibrations, such as Anderson et al. (2021).

Older data will be combined with newly acquired data. It is critical that consistent analytical procedures and data formatting be used to ensure that the data are robust and statistically significant, and that we obtain consistent results for overall comparisons with data obtained over the course of the contract.

2 – Criteria for USGS acceptance of the measured data include the following. For each sample analyzed for clumped isotope composition, measurements must be replicated on at least 3 separate analysis sessions on the mass spectrometer to ensure calculation of valid summary statistics. Sample replicate-level and sample summary-level results must be reported along with standard measurement quality data (check standards and calibration standards) to ensure data quality. In addition to mean values of isotopic compositions, sample level data uncertainty must be reported. This is preferred to be reported as the 95% confidence interval of the mean on both internal and external error. If after 3 successful replicate analyses of a given sample the D47 internal standard error (95% confidence interval on the mean) is greater than 0.04‰, additional replicates are to be run if additional sample powder remains.

3 – Data are expected to be measured and supporting summary reports and residual unconsumed sample material are expected to be sent to the USGS within a maximum of 6 months (180 days) of shipment to laboratory. The USGS will pay for shipment of samples to the laboratory. The laboratory is expected to pay for shipment of residual sample material to the USGS for return.

B - Deliverables:

1 - Measured data, supporting summary reports, and residual unconsumed material are expected to be sent to the USGS. Deliverables will include replicate-level and sample-summary level data tables in excel or .csv file formats, which will be sent to the USGS by email (email address will be provided once awarded). These files will contain sample and standard measurement data. If unexpected complications on the mass spectrometer or peripheral instruments may hinder timely analyses, communication with the USGS point of contact is expected. Data found to be unacceptable according to the above expectations will be analyzed again at no cost to the government.

Excess sample materials (powders, rock chips, etc.) will be returned to the requester when indicated on the original submission. If requested with initial delivery, all excess sample material shall be returned and received by the requester to be considered complete for the purposes of payment.

III - Supporting Information:

A - Place of Performance: Analyses are expected to occur in a specialized isotope geochemical laboratory in the United States. No third-party vendors or subcontracting of these analyses are permitted. Analysis needs to be run at place of the awardee’s institution.

B - Period of Performance: 02/13/2026 – 02/12/2031.

C- Level of Knowledge or Skills Required: The principal investigator (PI) of the laboratory must hold a doctorate degree in geochemistry or related field or have 5+ years of experience measuring clumped isotope analyses. The PI must have a history of publishing relevant clumped isotope datasets at high precision in peer review journal articles. The PI should not be the sole analyzer of samples in the laboratory. The primary operator/analyzer in the laboratory should have at least one year experience measuring clumped isotope data from geologic samples with a preference for analysis by laboratory technicians/managers with an advanced degree (MS/MA or PhD) in the geosciences, chemistry, or related field. Preference will be given to laboratories staffed by technicians or managers, qualified and capable of analyzing, standardizing, summarizing, and transmitting data to the USGS.