Penn State University (logo)
Indiana University (logo)
University of Minnesota (logo)
University of Maryland (logo)
Michigan State University (logo)
The University of Chicago (logo)
University of Iowa (logo)

Search

You searched for: Time Period 1950-1999 Remove constraint Time Period: 1950-1999
Number of results to display per page
View results as:

Search Results

1.
Vector Created with Sketch.

104 State Water Plan Watersheds: Pennsylvania penn-state

1998. Environmental Resources Research Institute. Digitized boundaries of 104 major watersheds defined in the Pennsylvania state water plan. The State Water Plan, originally developed in the 1970s,...

10.

Abandoned railroads of Indiana. indiana

1960?. Pen and ink.; Base map: Geological Survey (U.S.). State of Indiana, Scale 1:500,000, Washington, D.C., 1950. Scale approximately 1:2,027,520.

11.

Academy Gletscher: Greenland minnesota

1953. Projection: Polar Stereographic Projection; Series: AMS C501 Greenland 1:250,000 Topographic Series.

12.
Vector Created with Sketch.

Active Railroads: Pennsylvania penn-state

1996. Environmental Resources Research Institute. Location of active rail lines in Pennsylvania, digitized from 1:24,000 USGS topographic maps on a stable Mylar base.

33.
Vector Created with Sketch.

Aerial Photography Dates: Iowa, 1950s iowa

1950. Iowa Department of Natural Resources. Zipped file Contains a dateset of the centroids, with dates, of the individual images used.

34.
Vector Created with Sketch.

Aerial Photography Dates: Iowa, 1960s iowa

1960. Iowa Department of Natural Resources. This dataset is centroids with dates of the individual images used.

35.
Vector Created with Sketch.

Aerial Photography Dates: Iowa, 1970s iowa

1970. Iowa Department of Natural Resources. This shapefile has centroids with dates of all images used in this dataset.

37.

Aeromagnetic anomaly map of Minnesota, S-11 minnesota

1982. Chandler, Val W. Aeromagnetic anomaly (total magnetic intensity anomaly (relative to the earth's magnetic field, interpretation of magnetic data collected from airb...

38.

Aeromagnetic anomaly map of Minnesota, S-17 minnesota

1992. Chandler, Val W. Aeromagnetic anomaly (total magnetic intensity anomaly (relative to the earth's magnetic field, interpretation of magnetic data collected from airb...