SILICON AUDIO BOREHOLE SENSORS SOURCES SOUGHT The US Geological Survey (USGS) is conducting market research to determine the availability of qualified businesses capable of providing a Silicon Audio Low-Noise Optical Seismic Sensor as described in the attached Technical Specifications. This sources sought announcement is not a request for quote or proposal and the Government is not committed to award of a purchase order or contract pursuant to this announcement. The information resulting from this market research is simply for planning purposes to assist the Government in determining its acquisition strategy. The Government will not pay for any costs incurred in the preparation of information for responding to this notice. The North American Industry Classification System (NAICS) code: 334513, Instruments and Related Products Manufacturing for Measuring, Displaying and Controlling Industrial Process Variables, and associated size standard 750 apply to this announcement, along with Product Service Code: 6655, Geophysical Instruments. All responsible sources may submit a product data sheet detailing the ability to meet the Technical Specifications included with this announcement. Responses to this announcement shall only be accepted through electronic mail addressed to yangzhi_deng@ios.doi.gov and must be uploaded and received in their entirety no later than 06/16/2026 at 1500 PST. Proposals submitted by hardcopy or any web portal shall not be accepted or considered.