Pitiscus

D= 82 km
Center: 51¡S, 31¡E

Count Area: 1585 km^2
Observed Density (@ 1km): 12600 ± 2900
Age: 3.8 ± 0.1 (+sec: 3.8)
Stoffler epoch: Early Imbrian
Fit Density (@ 1km): 13000 ± 1700
PF fit: good, largest craters in excess

Age calculation notes:
Good fit (SM).
Good fit for small craters - bad fit for large craters (this is a "right ear" crater) - use as is; adding OSs doesn't change fit or age (MRK).

USGS geology: 
Crater rim mapped as Nectarian (Pre-Imbrian is their term?). Most of crater floor mapped as (volcanic) fill with an Imbrian age - some may be original floor.

Wilhelms: 
Nectarian (all materials)

Floor material: 
Best guess is not original. Smooth flat floor, edges meeting wall are sharp and look embayed, see what look like flow fronts/wrinkle ridges. Small central peak. Also surrounded by other craters filled with mare. Material looks fresh. Hard?

Geology Observations: 
Ejecta blanket very eroded. Rim looks eroded, but still some sharpness. Small central peak. Floor flat. A few secondary chains/clusters, generally fresher, with larger craters up to ~ 1.5 km.

SFD Observations: 
Small craters (< 1.5 km) dominated by classes 3 & 4. Large craters dominated by fresher classes. Distribution < 1.5 km steep. Shallow "right ear" (more than 1 crater!). Slope(Diff) = 4.9 ± 0.5.

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

Notes from Brian's adjustment:
- Counting boundary:
	Boundary includes part of the crater wall at 2:00 position, but is OK.
	Minor problem with central peak can probably be ignored too.
	Craters appear to be marked OK, though 3's vs 4's could be debated.
	Some class 4's were missed.
	I would recommend moving the boundary at the 7:00 position to exclude the large crater and what looks like its ejecta blanket up to about 6:00. -MRK

- Secondaries:
	Two clusters around 1:00 have not been marked as secondaries.

- Removal of large, buried craters:
	Looks OK.

- Size adjustment of large craters:
	Two of the largest craters are marked too small.

- Explaining unusual cases:
	Pitiscus is listed in red (not sure why - ble).
	Match column says "wide-v".

- Future actions:
	Had LOTS of problems with the new shape file - it made JMARS act very
weird. I finally stopped using it... not sure if it's a problem with my JMARS
or the new shape file is somehow corrupt.
Possibly and issue with having shape file selected in "Main" tab, not crater tool selected. - MRK

- Completed actions:
	Counting boundary adjusted (MRK) and extra craters removed (BLE)
	Two largest craters are no longer in the counting boundary (BLE)
	Added some missing class 4 craters and modified some 3's/4's (BLE)
	Marked the missing clustered craters (BLE)

Last Edited by MRK 12/17/2012