I've have time machine backups that are showing modified system files starting about May of 2011. Odd this original question is from April 2011.
This is all from a "blank" logical volume just erased in using the Disk Utility App. I'm trying to figure out why I have 200+ MB of data after erasing drives. It maybe nothing but it just seems odd that this would be stuck there. I've seen no trustworthy explanation of any cause so I must assume the worst since the typical attitude would be that it's nothing to worry about.
Below are the files on the disk, notice the _unknown user who owns many of them. The date is off, it was erased yesterday July 8 2017 but dates go back to July 1 for some reason. I just pasted this from the Terminal where's its displayed using the default black text on a white background but it pasted here in what looks like the "Grass" color scheme which I have never once used.
Apologies in advance to all of you who've turned to stone from viewing stdout.
drwxrwxr-x 8 root admin 340 Jul 3 07:38 .
drwxr-xr-x@ 7 root wheel 238 Jul 8 21:52 ..
-rw-r--r--@ 1 _unknown _unknown 8196 Jul 7 17:13 .DS_Store
drwx------ 5 _unknown _unknown 170 Jul 1 14:18 .Spotlight-V100
d-wx-wx-wt 3 root wheel 102 Jul 8 21:49 .Trashes
drwx------ 9 _unknown _unknown 306 Jul 8 21:50 .fseventsd
/Volumes/4//.Spotlight-V100:
total 8
drwx------ 5 _unknown _unknown 170 Jul 1 14:18 .
drwxrwxr-x 8 root admin 340 Jul 3 07:38 ..
drwx------ 3 _unknown _unknown 102 Jul 1 14:18 Store-V1
drwx------ 3 _unknown _unknown 102 Jul 1 14:18 Store-V2
-rw------- 1 _unknown _unknown 4006 Jul 1 14:18 VolumeConfiguration.plist
/Volumes/4//.Spotlight-V100/Store-V1:
total 8
drwx------ 3 _unknown _unknown 102 Jul 1 14:18 .
drwx------ 5 _unknown _unknown 170 Jul 1 14:18 ..
-rw------- 1 _unknown _unknown 348 Jul 1 14:18 VolumeConfig.plist
/Volumes/4//.Spotlight-V100/Store-V2:
total 0
drwx------ 3 _unknown _unknown 102 Jul 1 14:18 .
drwx------ 5 _unknown _unknown 170 Jul 1 14:18 ..
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 70491854-53C4-4610-AEE2-28DB3175DF5E
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E:
total 1600
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 .
drwx------ 3 _unknown _unknown 102 Jul 1 14:18 ..
-rw------- 1 _unknown _unknown 118784 Jul 8 21:55 .store.db
-rw------- 1 root _unknown 65536 Jul 8 21:50 0.directoryStoreFile
-rw------- 1 root _unknown 1088 Jul 7 18:17 0.directoryStoreFile.shadow
-rw------- 1 root _unknown 66240 Jul 7 18:17 0.indexArrays
-rw------- 1 root _unknown 8 Jul 7 18:17 0.indexCompactDirectory
-rw------- 1 root _unknown 2056 Jul 7 18:17 0.indexDirectory
-rw------- 1 root _unknown 2 Jul 7 18:17 0.indexGroups
-rw------- 1 root _unknown 4096 Jul 7 18:17 0.indexHead
-rw------- 1 root _unknown 16 Jul 7 18:17 0.indexIds
-rw------- 1 root _unknown 8 Jul 7 18:17 0.indexPositions
-rw------- 1 root _unknown 100 Jul 7 18:17 0.indexPostings
-rw------- 1 root _unknown 12 Jul 7 18:17 0.indexUpdates
-rw------- 1 root _unknown 2 Jul 7 18:17 0.shadowIndexGroups
-rw------- 1 root _unknown 4096 Jul 7 18:17 0.shadowIndexHead
-rw------- 1 _unknown _unknown 0 Jul 1 14:18 Cab.created
-rw------- 1 _unknown _unknown 0 Jul 1 15:39 Cab.modified
-rw------- 1 _unknown _unknown 0 Jul 1 14:18 Lion.created
-rw------- 1 _unknown _unknown 28 Jul 8 21:50 indexState
-rw------- 1 _unknown _unknown 0 Jul 1 14:18 journalExclusion
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.assisted_import_post
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.assisted_import_pre
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.corespotlight
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.health_check
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.live
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.live_priority
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.live_system
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.live_user
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.migration
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 journals.migration_secondchance
drwx------ 2 _unknown _unknown 68 Jul 1 15:39 journals.repair
drwx------ 3 _unknown _unknown 102 Jul 7 11:20 journals.scan
-rw------- 1 root _unknown 65536 Jul 8 21:50 live.0.directoryStoreFile
-rw------- 1 root _unknown 1088 Jul 7 18:17 live.0.directoryStoreFile.shadow
-rw------- 1 root _unknown 65536 Jul 8 21:50 live.0.indexArrays
-rw------- 1 root _unknown 1024 Jul 8 21:50 live.0.indexCompactDirectory
-rw------- 1 root _unknown 8224 Jul 8 21:50 live.0.indexDirectory
-rw------- 1 root _unknown 3277 Jul 8 21:50 live.0.indexGroups
-rw------- 1 root _unknown 4096 Jul 7 18:17 live.0.indexHead
-rw------- 1 root _unknown 32768 Jul 8 21:50 live.0.indexIds
-rw------- 1 root _unknown 8192 Jul 8 21:50 live.0.indexPositionTable
-rw------- 1 root _unknown 4096 Jul 8 21:50 live.0.indexPositions
-rw------- 1 root _unknown 4096 Jul 8 21:50 live.0.indexPostings
-rw------- 1 root _unknown 8192 Jul 8 21:50 live.0.indexTermIds
-rw------- 1 root _unknown 0 Jul 7 18:17 live.0.indexUpdates
-rw------- 1 root _unknown 65536 Jul 7 18:17 live.0.shadowIndexArrays
-rw------- 1 root _unknown 8 Jul 7 18:17 live.0.shadowIndexCompactDirectory
-rw------- 1 root _unknown 2056 Jul 7 18:17 live.0.shadowIndexDirectory
-rw------- 1 root _unknown 1 Jul 7 18:17 live.0.shadowIndexGroups
-rw------- 1 root _unknown 4096 Jul 7 18:17 live.0.shadowIndexHead
-rw------- 1 root _unknown 0 Jul 7 18:17 live.0.shadowIndexPositionTable
-rw------- 1 root _unknown 0 Jul 7 18:17 live.0.shadowIndexTermIds
-rw------- 1 root _unknown 18 Jul 8 21:50 permStore
-rw------- 1 _unknown _unknown 65536 Jul 8 21:50 reverseDirectoryStore
-rw------- 1 _unknown _unknown 3136 Jul 1 14:18 reverseDirectoryStore.shadow
-rw------- 1 _unknown _unknown 1 Jul 8 21:50 reverseStore.updates
-rw-r--r-- 1 _unknown _unknown 4 Jul 8 21:55 shutdown_time
-rw------- 1 _unknown _unknown 118784 Jul 7 18:17 store.db
-rw------- 1 _unknown _unknown 8 Jul 8 21:50 store.updates
-rw-r--r-- 1 _unknown _unknown 4 Jul 1 14:18 store_generation
-rw------- 1 _unknown _unknown 0 Jul 1 14:18 tmp.Cab
-rw------- 1 _unknown _unknown 0 Jul 1 14:18 tmp.Lion
-rw------- 1 _unknown _unknown 0 Jul 1 14:18 tmp.SnowLeopard
-rw------- 1 _unknown _unknown 1968 Jul 1 14:18 tmp.spotlight.loc
-rw------- 1 _unknown _unknown 4096 Jul 8 21:50 tmp.spotlight.state
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.assisted_import_post:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.assisted_import_pre:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.corespotlight:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.health_check:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.live:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.live_priority:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.live_system:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.live_user:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.migration:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.migration_secondchance:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 14:18 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.repair:
total 0
drwx------ 2 _unknown _unknown 68 Jul 1 15:39 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
/Volumes/4//.Spotlight-V100/Store-V2/70491854-53C4-4610-AEE2-28DB3175DF5E/journa ls.scan:
total 0
drwx------ 3 _unknown _unknown 102 Jul 7 11:20 .
drwx------ 66 _unknown _unknown 2244 Jul 7 18:17 ..
-rw------- 1 root _unknown 0 Jul 7 11:20 retire.170
/Volumes/4//.Trashes:
total 0
d-wx-wx-wt 3 root wheel 102 Jul 8 21:49 .
drwxrwxr-x 8 root admin 340 Jul 3 07:38 ..
drwx------@ 2 a1 wheel 68 Jul 8 21:49 501
/Volumes/4//.Trashes/501:
total 0
drwx------@ 2 a1 wheel 68 Jul 8 21:49 .
d-wx-wx-wt 3 root wheel 102 Jul 8 21:49 ..
/Volumes/4//.fseventsd:
total 56
drwx------ 9 _unknown _unknown 306 Jul 8 21:50 .
drwxrwxr-x 8 root admin 340 Jul 3 07:38 ..
-rw------- 1 root _unknown 72 Jul 8 21:50 0000000000002990
-rw------- 1 root _unknown 69 Jul 8 21:50 0000000000002991
-rw------- 1 root _unknown 43 Jul 8 21:50 000000000000513e
-rw------- 1 root _unknown 70 Jul 8 21:50 000000000000513f
-rw------- 1 root _unknown 38 Jul 8 21:50 0000000000005140
-rw------- 1 root _unknown 70 Jul 8 21:50 0000000000005141
-rw------- 1 root _unknown 36 Jul 8 21:50 fseventsd-uuid
Hexdump doesn't show me what could be taking up that much space either it just says "shadow volume" a lot. Please notice the // thats been used.