Manzinus

D=98 km
Center: 68¡S, 27¡E

Count Area: 1924 km^2
Observed Density (@ 1km): 17700 ± 3100
Age: 3.8 ± 0.1 (+sec: 4.0)
Stoffler epoch: Early Imbrian
Fit Density (@ 1km): 18100 ± 800
PF fit: good?, but lots of secondaries in image

Age calculation notes:
Good fit (SM).
Fit is pretty good - use as is; adding OSs does make slightly older - fit does not change much though (MRK).

USGS geology: 
Crater rim material mapped as Pre-Nectarian. Floor material mapped as fill with Imbrian age (ejecta not mare).

Wilhelms: 
Crater is Pre-Nectarian. (all materials)

Floor material: 
Best guess is not original. Very smooth flat floor, material has sharp contacts with wall that look embayed, fill in one larger crater too, no central peak. Also other filled larger craters nearby. Material looks relatively fresh. Hard?

Geology Observations: 
Possibly small areas of ejecta near rim. Rim is eroded (more so on the east side). No central peak. Floor very smooth and flat. Several secondary chains/clusters with various sized craters (up to ~ 3 km) of various degradation states, but mostly degraded.

SFD Observations: 
Craters < ~ 2 km dominated only by class 3 and 4. Largest craters dominated by class 2. Has steep SFD for small craters (< ~ 1.3 km). Becomes flat for larger craters. Possible shallow "right ear" (more flat than shallow). Slope(Diff)=5.2 ± 0.4 (doesn't pass through last two points).

Discussion notes: 
large fraction of secondaries, skeptical about identifications, crater not likely good candidate for PF comparison and age

Notes from Brian's adjustment:
- Counting boundary:
	Suggest changing the marking boundary to eliminate a collapse area and large crater at 6:30?
	A few class 4's were missed, but not bad.

- Secondaries:
	Pretty good, but a few more should have been marked.

- Removal of large, buried craters:
	Adjust boundary to remove one large class 4 crater.

- Size adjustment of large craters:
	If the boundary is not readjusted, grow the large class 4 crater.

- Explaining unusual cases:
	The one large class 4 crater was probably creating a right lobe.

- Future actions:

- Completed actions:
	Boundary remarked (Michelle).
	Changed many secondaries (BLE).
	Add many missing class 3's and 4's (BLE).
	Changed a few primaries/secondaries and a few class designations (MRK).

Last Edited by MRK 12/13/2012