The current database consists of location 9,032 entries. The surface-based, point data include 5,272, 6,939, and 903 density, magnetic susceptibility, and NRM measurements, respectively. Downhole data from 146 drillcore have also been incorporated, yielding an additional 1,145 and 9,622 measurements of density and magnetic susceptibility, respectively. Geologic interpretation of gravity and magnetic anomaly data in a given area is greatly enhanced if density, magnetic susceptibility (MS) and natural remanent magnetization (NRM) data are available for representative rock-types (Chandler and others, 2008). Along with geologic information from outcrop and drill-holes, rock property data help relate geophysical anomaly...
Collection of scanned mylar overlays and topographic field maps displaying outcrop, structural measurements, traverses, and geologic units.
Collection of scanned 35mm film slides of outcrop and field sites from various MGS geologists, mostly pertaining to Precambrian geology in Minnesota.
Minnesota Geological Survey, in cooperation with industry, sampled the State of Minnesota and adjacent regions for till geochemistry and indicator minerals at a 30-km spacing during summer 2004. Within target cells, each a quarter-degree latitude by a half-degree longitude, till from between about 1 and 2 m depth was sampled by filling a 15 liter plastic pail. At a few sites, vertical profiles were collected. In addition, three transects to the north were sampled, to help identify sediments derived by long-distance glacial transport, to obtain reference samples from the Thompson nickel belt, and also to extend sampling to the limit of Hudson Bay-derived carbonate-bearing sediments, to permit comparison to Minnesota...
All sediment samples from auger holes, outcrops, and cores are processed to determine texture. The 1-2 mm coarse sand fraction is packaged separately, and about half of these fractions are categorized lithologically by a glacial geologist. The data are recorded on paper data sheets and in a database.
Hand specimens of rocks collected as a part of field work conducted primarily by present and former WGNHS staff members. Samples date from the early 20th century to the 1990s and were collected throughout the state. Many of the samples are described in the historical field notebook collection, and relationships between the samples and the field notebooks have been established and captured in identifiers. Locations for samples were taken from field notes, maps, and accession lists. There are approximately 5,700 hand samples in this collection.
Static metadata (current to June 2023) of Minnesota's borehole drill cuttings collection maintained by the Minnesota Geological Survey (MGS). This collection of over 6,400 sets of drill cuttings dates as far back as the late 1800s. The collection is stored in our soil lab at our office and is accessible to the public by appointment. Each borehole cutting set is assigned a MGS lab number upon arrival, processed and washed by UMN student soil lab workers, and stored chronologically in cardboard boxes. Each cutting set cardboard box contains multiple paper envelopes representing a sample taken at that depth. Each paper envelope contains ~100-200 grams of original sample and ~100 grams of washed sample processed by...