User:B3ASTM0D37200/Anna Jespersen

At the age of 19, Jespersen started teaching at a rural school located in Day County South Dakota. She was also a geologist with the U.S. Geological Survey in Washington, D.C. From 1941 to 1945, she worked as an editor with John Wiley & Sons publishing company before deciding to move back to Washington, D.C. and continue working for the U.S. Geological Survey. Anna also worked internationally, attending meetings of the International Geological Congress, including meetings in Montreal, Prague, Iceland, Copenhagen, and Algiers.

In 1963, she co-published the geological survey, Aeromagnetic Interpretation of the Geology of the Greenwood Lake and Sloatsburg quadrangles, New York and New Jersey, with fellow geologist Andrew Griscom.

In 1964, Jespersen created a map titled Aeromagnetic Interpretation of the Globe - Miami Copper District, Gila and Pinal Counties, Arizona. This map was created under the publishing organization U.S. Geological Survey. To create this, quadrangles in the highlands (Gila and Pinal counties) were surveyed by the Geological Survey in order to gather additional information in regard to the magnetite deposits within bodies of water and marshes located in the Precambrian belt. The copper- mineralized belt Jespersen had surveyed was discovered in 1984. Initially only 60 percent of the copper belt was covered in volcanic and surficial deposits. Due to this discovery, Jespersen had performed an airborne magnetic survey. With this survey she hoped to discover additional areas for more copper prospecting. These areas were aero magnetically surveyed using a continuously recording AN/ASQ-3A airborne magnetometer installed on a twin-engine aircraft. The flight path of the aircraft was recorded during the process by a gyro stabilized 35-millimeter continuous-strip-film camera as well as a radar altimeter to ensure accuracy in the map. The data collected within this survey and the corresponding map contributes to the geologic mapping processes significantly. The mapping process is now able to account for more detail by allowing for different layers of rock to be analyzed in terms of magnetic data and then illustrated in a comprehensive fashion. Within their studies, Jesperson and Hotz mapped out for four different kinds of rocks. In their discovery they found Meta-Sedimentary rocks, Quartz-Plagioclase Gneiss, Hornblende Granite and Granite Pegmatite. They also found faults occurring through the youngest layers of the rock. The fault ran through the rocks that contained volcanic and surficial deposits.