Statement_of_Work_for_RFI_1.pdf

PERFORMANCE-BASED WORK STATEMENT

I. GENERAL INFORMATION

A. Introduction (general description of services)

The USGS Geology, Minerals, Energy, and Geophysics (GMEG) Science Center requires zircon uranium-lead (U-Pb) geochronology combined with mineral chemistry of samples collected from igneous and metamorphic rocks in southern Nevada, near Twentynine Palms in California, and near Yuma, California. These analyses will support ongoing research for Colorado River evolution, Miocene tectonics in California, and fault dynamics in California, and provide robust updates to geologic maps in the associated regions.

B. Background

Zircons extracted from plutonic and metamorphic rocks in the Spirit Mountain, Yuma, and Twentynine Palms areas. Precise dating of the zircons is required to constrain the age of pluton formation which constrains the timing of the Miocene tectonic uplift, a major tectonic event in western North America. One pluton was intruded by material potentially related to the other. Other research in southern California will test the theory that the Pinto Mountain fault offsets rocks by up to 17 km in the area north of Joshua Tree National Park. This research is part of the work of the Lower Colorado River Geologic Mapping Project and the Basin and Range Geologic Mapping Project in the Geology, Minerals, Energy and Geophysics Science Center, for the National Cooperative Geologic Mapping Project in strategic alignment with:

Interim Strategic Priority 4: Safety and protections for our people, property, and resources; Interim Strategic Priority 8: Service to communities that rely on Interior’s capacity for science, data, and technologies, and;

Interim Strategic Priority 12: Implementing Secretarial and Administration priorities, legislation, and directed initiatives.

The research addresses questions related to mineral resources as well as advancing general understanding of the regional geologic history and geologic processes.

B. Definitions

LA-ICP-MS: Laser ablation inductively-coupled plasma mass spectrometry

C. Scope Processing, dating, and geochemistry of zircons from ~28 samples/localities, ~50 zircons per sample. We have collected samples from a variety of plutonic, volcanic, and metamorphic complexes. In combination with bulk major and trace geochemistry, with mineral chemistry, the U-Pb isotope data will be used to calculate zircon ages to constrain magmatic sources, petrogenetic models, regional metamorphism, and regional faulting.

II. WORK REQUIREMENTS

A. Technical Requirements.

1. Describe specific work requirements and/or work products LA-ICP-MS: Laser ablation inductively-coupled plasma mass spectrometry Processing, dating, and geochemistry of zircons (and maybe calcite) from ~28 samples/localities, ~50 zircons per sample. Appropriate international standards for zircon U-Pb and geochemistry are inserted into the analysis run. Samples are prepared using standard zircon mineral separation techniques using a water table, magnetic separation, and heavy liquid separation. Individual mineral grains will be picked in the laboratory using optical characteristics in a dissecting scope, then mounted in epoxy pucks.

2. Criteria for acceptance of Product or Service Analyses must meet the requirements of the lab’s quality control and quality assurance specialists. The Government will review the submitted deliverables for compliance with the requirements of the Statement of Work

B. Deliverables.

1. Characteristics for work product described in II.A.1., identified by name and quantity.

Delivery of individual zircon isotope concentrations, ratios, trace element concentrations, and calculated ages for each sample (calibrated to instrument conditions and standards). This will also include the underlying data, along with return of zircons. A description of analytical techniques and methods of data reduction will also be provided, including how uncertainties are calculated.

2. Delivery dates for work/product to be completed and point of delivery.

Depending on lab schedules, the work for 28 samples should be completed within 12 months of the award of the contract. Digital data can be transferred to the USGS (POC: TBA) by email or other means of data delivery. Epoxy pucks will be returned to the USGS.

III. SUPPORTING INFORMATION

A. Place of Performance.

Vendor’s LA-ICP-MS Laboratory

B. Period of Performance The work will require ~15 days of lab time, performed within 12 months from the award of the contract.

C. Government Furnished Property (GFP): list property and its value.

None