Statement_of_Work_1.pdf

STATEMENT OF WORK

I. GENERAL INFORMATION

A. Introduction. The USGS Geology, Minerals, Energy, and Geophysics (GMEG) Science Center needs zircon mineral separations and uranium-lead (U-Pb) geochronologic analysis of zircon for research underway for the project “National assessment of Ni, Co, V, Cr, and PGE associated with mafic/ultramafic magmatic mineral systems”.

B. Background. GMEG scientists are conducting ongoing research efforts on critical commodities associated with mafic and ultramafic rocks. We have the need to provide geochronology constraints on rocks that may host mineralization. Zircon (a minerals that can be dated) is not common in these rocks and can be difficult to extract. We will use ages of detrital zircon to bracket the age of ultramafic volcanic and plutonic rocks.

Samples will include metasedimentary rocks intercalated with volcanic rocks and overlying erosional surfaces on intrusions.

II. WORK REQUIREMENTS

A. Technical Requirements.

1. Specific work requirements. The contractor shall have experience in all aspects of mineral separation and detrital zircon geochronology using LA-ICPMS methods.

The mineral separation work must be done in a laboratory in which the crushers, sieves, and other equipment used in the separation process are carefully cleaned and monitored to prevent cross contamination of samples.

Work tasks to be performed include (a) separation of zircon grains from 10 bulk rock samples provided by the USGS; (b) U/Pb detrital age analysis for up to 110 zircon grains in each of the 10 samples using LA-ICPMS; (c) data reduction and analysis of U/Pb ages; and (d) delivery of zircon sample mounts used for the analysis.

2. Criteria for acceptance: The results are acceptable if, after delivery and review, the

U/Pb crystallization age analysis are technically suitable for publication in a peer-reviewed scientific paper. Mineral separates for the other samples should include all intermediate and final fractions from the separation process.

B. Deliverables.

1. For the 10 samples submitted for U/Pb LA- ICPMS detrital age analysis, the contractor shall provide an Excel file that includes the raw data and a preliminary analysis of grain age populations based on Gaussian deconvolution of the analyzed grains, analytical data for standards, and an error analysis. In addition, the contractor will provide a description (Word or PDF file) of the analytical methods used to obtain the results.

2. Delivery dates and point of delivery. Delivery shall be not later than 8 months from the time the lab receives the samples. Deliverables shall be sent to US Geological Survey, 904 W Riverside Ave., Suite 202, Spokane, WA, 99201

III. SUPPORTING INFORMATION

A. Place of Performance. Contractors’ location

B. Period of Performance. Twelve months from the date of award

C. Government Furnished Samples. Ten samples will be submitted for zircon separation and LA-ICPMS analysis of detrital zircons.

D. Special Considerations.

1. The contractor will ship any unprocessed, left-over rock to USGS.

2. Contractor retains copyright to proprietary information on methods and techniques in reports delivered to the USGS.

3. Security/Privacy issues: None.