This publication presents a database of geologic analogs useful for the assessment of undiscovered oil and gas resources. Particularly in frontier areas, where few oil and gas fields have been discovered, assessment methods such as discovery process models may not be usable. In such cases, comparison of the assessment area to geologically similar but more maturely explored areas may be more appropriate. This analog database consists of 246 assessment units, based on the U.S. Geological Survey 2000 World Petroleum Assessment. Besides geologic data to facilitate comparisons, the database includes data pertaining to numbers and sizes of oil and gas fields and the properties of their produced fluids.