Date of Award
Master of Science
Geological and Environmental Sciences
Dr. William A. Smith
Dr. Estella Atekwana
Dr. William B. Harrison III
Masters Thesis-Open Access
A detailed gravity study consisting of 945 measurements was carried out in Branch County, Michigan. The objectives of this study are to determine if: (a) structural trends interpreted from regional gravity data in southwestern Michigan are also observed in a more detailed survey in Branch County and (b) any relationship exists between observed geophysical anomalies, geological structures and overlying basin sediments.
The resulting gravity map indicates that NW-SE, NE-SW, and N-S trends are more clearly identified comprising several elliptical highs and lows. Variations in the isopachs of some of the overlying Phanerozoic formations area are also coincident with gravity anomalies. The implication of this is that basement fault reactivation had occurred, evidently ceasing during the Middle Ordovician. Two-dimensional modeling along profiles in Branch County and southwest Michigan, correlated with drill-hole data, suggest that the anomaly pattern is probably due to lateral changes in basement petrology influenced by local mafic intrusions within the basement
Gutaj, "The Relationship between Basement Structure and Overlying Sediments in the Michigan Basin: A Detailed Gravity Investigation" (1994). Master's Theses. 4432.