A Ground-Magnetic Study of Rose Dome, Woodson County, Kansas

The present study conducted a group-magnetic survey at Rose Dome in Woodson County, Kansas, to delineate the boundary of the physiographic feature, attempt to recognize separate intrusive mafic sills in the subsurface, and to locate a possible feeder dike. The magnetic measurements ranged from 52,700 nT to 54,300 nT. A zone of northeast trending anomalies in the northwest corner of the survey area may represent an area of faulting that brought more magnetic material nearer the surface, and/or where the lamproite sills terminate. A magnetic low anomaly located in the northwestern corner of the survey area probably represents an area of less magnetic sedimentary rock. A large magnetic high located in the eastern portion of the survey area may represent an area that has been faulted. A centrally located west-to eat high-low anomaly may represent lamproite sills in the subsurface or a feeder dike zone for the intrusion. The resolution of the data is too coarse to recognize individual sills. However, the magnetic anomalies appear to be useful in targeting the depth to the sills in the subsurface country rock