Possible models for the formation of the Pepperoni Features:

DRUMLINS:  If the pepperoni structures are drumlins, the leading edge of the receding ice sheet would have come from a northeast extension of the Ross Ice sheet at its glacial maximum.  Data suggests the glacial maximum occurred between 10 and 20,000 years ago.  The ice would have had a maximum thickness of approximately 700 meters and would have extended approximately 100 km from its current edge into the Ross Sea Basin in the direction of the features.

 


SEAMOUNTS: Suggestions that the pepperoni are volcanic features are less likely.  Magnetic data from a variety of sources show large magnetic anomalies in this region of the Ross Sea associated with both marine and terrestrial volcanic features.  Near to the pepperoni  features are sea mounts that have large magnetic and gravitational variation which is expected for these volcanic features.  The pepperoni  did not show variation in either the magnetic or gravity data indicating that they were not volcanic in origin.

TUYAS:  Typical sub glacial volcanic features called tuyas are nearly circular in structure just similar to the pepperoni features are. 


DRUMLINS: These features demonstrate the classic drumlin form in terms of their elevation.  The slope in the direction of the advancing ice edge is very steep.  In those observed the change in elevation is 100 meters over a distance of .2 km.  In the opposite direction, a tapered gradual slope is found in classic drumlins and also those observed in the Ross Sea.  Those in the Ross Sea had a change of 100 meters in elevation over a distance of 2.0 km.  This data is consistent with drumlins observed in terrestrial deposition.

PINGOS:  Pingos are typically formed by uplift of large blocks covered by earth which form large mounds as the ice moves upward.  These features are not associated with glaciers.  Pingos can also be formed as a result ob the uplift of gas hydrates, which are a type of crystalline ice solid in which gas molecules are trapped between the frozen water molecules


OTHER IDEAS: Possible reasons for the circular shape of the pepperoni may be due to marine deposition rather than terrestrial deposition.  The Ross Sea formations have been protected from weathering in their marine environment and these formations are associated with ice sheets that are still present. The pepperoni showed little reflectivity in the bathymetric data.  Sub glacial formations typically have glassy basalts that would have high reflectivity in the bathymetric data.