Tyrannosaurus bataar eggs

[Mikiel <Mikiel@ASU.Edu>]

After posting my original message about the pair of T. bataar eggs in the 
geology museum at ASU, I received many messages asking for more details.  
So, here they are:

The pair of eggs are considered to be one specimen of an estimated set of 
30 separate specimens, most of which were found in pairs, totaling about 
50 eggs.  They were found in the Gaugao formation, Xixia county, Henan 
Province, China.  The formation is (lower?) Cretaceous.  Many of the eggs 
were exposed by flood waters, and others were discovered by farmers 
digging a canal.
The eggs are definitely theropodous, probably tyrannosaurid, and maybe 
Tyrannosaurus bataar in origin. (They were originally considered 
to be Tarbosaurus bataar, but tarbosaurs have been refered to the 
Tyrannosauridae.) Associated embryonic bones were found with 
some of the specimens, but not with the pair we have here.
The eggs are 18.5 and 17.25 inches long, and approximately 7 to 8 inches 
wide. Further, they were partially pancaked after deposition, so the 
width may be exaggerated.  They are generally broken up, but not 
disassociated, and were probably 16 or so inches in length before 
deposition. The shell itself appears to be about 2mm thick, and has 
a texture rather more like motorcycle leather (is that a scientific 
term?) than the basket-ball type texture of other eggs.
The surrounding matrix appears to be a very fine sandstone or perhaps 
mudstone.
As far as I can discover, there was no evidence of an excavated nest, as 
is the case with hadrosaurs for example.
I know of no plans for further x-ray studies in order to definitely nail 
the species responsible.
I know almost nothing about the geology of China, but perhaps someone who 
does can tell us a bit about the depositional environment in this area.

-Mikiel