McLaughlin

D=80 km
Center: 47¡N, 267¡E

Count Area: 1169 km^2
Observed Density (@ 1km): 8600 ± 2800
Age: 3.7 ± 0.1 (+sec: 3.7)
Stoffler epoch: Late Imbrian
Fit Density (@ 1km): 10200 ± 1500
PF fit: good, some variation at large diameters

Age calculation notes:
Poor fit (SM).
Small craters are OK - large craters fit within error (this is a "right ear" crater) - perhaps can improve fit if large craters are ignored; adding OSs does not change fit or age. Fit does look slightly improved when forced to fit small craters (HN2) - age doesn't change much (MRK).

USGS geology: 
Crater material mapped as Pre-Nectarian. Floor material mapped as fill with Imbrian age (possibly ejecta).

Wilhelms: 
Rim is Nectarian. Floor is Imbrian fill - possibly Imbrium ejecta(?).

Floor material: 
Best guess is not original. Very smooth flat floor, material has sharp contact with wall and looks embayed, small central peak. Also surrounded by other filled craters and mare. Material looks relatively fresh. Hard?

Geology Observations: 
No ejecta blanket visible. Rim is eroded. Small central mound - remainder of peak(?) - looks eroded. Floor very smooth and flat. Areas of floor that look textured - very degraded craters? A few secondary chains/clusters with smaller sized craters (up to ~ 1 km) of various degradation states.

SFD Observations: 
Smallest craters < ~ 1.5 m dominated by class 4, although 3 and 2 not much lower density. Larger craters dominated by class 1 and 3. Has steep SFD for small craters (< ~ 1.5 km). Becomes shallow for larger craters. Shallow "right ear" (more than one crater, but only one point). Slope(Diff) = 5.0 ± 0.8.

Discussion notes: 
"v" feature not statistically significant, change MPF fit to "OK"

Notes from Brian's adjustment:
- Counting boundary:
	Questionable lobe near 8:00.
	Many faint craters missed at top and middle.

- Secondaries:
	Iffy markings at 9:00, two clusters missed.

- Removal of large, buried craters:
	None.

- Size adjustment of large craters:
	One large crater should be larger.

- Explaining unusual cases:

- Future actions:

- Completed actions:
	Changed the boundary (Michelle).
	Marked missing faint craters and fixed sizes (BLE).
	Fixed cluster markings (BLE).
	Added a few secondaries and changed a few class designations (MRK).

Last Edited by MRK 12/14/2012