Index to Marine and Lacustrine Geological Samples (IMLGS)

The Index to Marine and Lacustrine Geological Samples (IMLGS) describes and provides access to ocean floor and lakebed rock and sediment samples curated by participating institutional and government repositories in the U.S., Canada, the United Kingdom, France, and Germany. Each curatorial facility prepares and submits data about their own collection to NCEI for inclusion in the IMLGS. NCEI, on behalf of the Curator community, maintains the IMLGS database and a dedicated web application for data discovery and access. Physical material from most samples may be requested from the responsible Curator for scientific research using contact information provided in IMLGS data listings. As of July 2023, the IMLGS includes information for 228,785 discrete seabed and lakebed cores, grabs, dredges, and drill holes worldwide.

Minimum sample information required for the IMLGS includes ship/platform name, cruise ID, sample ID, sampling device, and latitude/longitude. Water depth, collection date, storage method, and principal investigator are usually included. Core dimensions and depth to top and bottom of interval is available for many core samples. Descriptions, comments, physiographic province, lithology, texture, mineralogy, other components, glass remarks, metamorphism information, weathering information, color, and geologic age are included for some samples. An International Generic Sample Number (IGSN) is included, if available. Links are also provided to related data and images at NCEI, partner institutions, and to other sources of information including the System for Earth SAmple Registration (SESAR) and the Rolling Deck to Repository (R2R).

The IMLGS database was initially designed by a group of Curators, in cooperation with NGDC (now NCEI), at a series of meetings sponsored by the U.S. National Science Foundation (NSF) beginning in 1977. The Curators group continues to meet annually to share best practices and oversee the IMLGS database.