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Advances in Modeling Aeromagnetic Anomalies Related to Faults in Sedimentary Basins—. Lessons Learned from the Rio Grande Rift, New Mexico. V.J.S. (“Tien”) Grauch Mark R. Hudson U.S. Geological Survey Denver, Colorado, USA. Traditional Magnetic Fault Models. Ground Traverse.
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Advances in Modeling Aeromagnetic Anomalies Related to Faults in Sedimentary Basins— Lessons Learned from the Rio Grande Rift, New Mexico V.J.S. (“Tien”) Grauch Mark R. Hudson U.S. Geological Survey Denver, Colorado, USA
Ground Traverse Magnetic Surveys in Sedimentary Basins Regional Airborne Survey magneticbasement 750 • Near-surface layers swamp the signal • Model as contact/step 1000 • Magnetic basement swamps the signal • - Model as steps or offset layers
Advances in Airborne Surveys High-resolution Airborne Survey • MULTIPLE layers are resolved • Traditional models may not be appropriate 750 1000
Central Rio Grande Rift Rift sediments Syn-rift volcanics Pre-rift, mainly sedimentary rocks Precambrian basement
Rio Rancho Area Aeromagnetic Surveys for the Central Rio Grande Rift Flown 1996-1998 • Specifications • Fixed-wing aircraft • E-W lines 100-150 m apart • Terrain clearance 100-150 m
View to the South Rio Rancho Aeromagnetic Data
The Concept of Magnetic-Contrast Layers E W MAGNETIC CONTRAST
Advances in Airborne Surveys High-resolution Airborne Survey • MULTIPLE layers are resolved • Traditional models may not be appropriate • Use equivalent magnetic-contrast layers • Applicable to any layered environment