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a consistent width throughout its length, and was also about 30 to 35 cm (12-14 in)
wide, flaring some as it connected with the rock holding the plastered specimen.
I waited until the next day to write and send Dave my assessment of what was
depicted in the photo. It went like this:
Hypotheses
:
1.
Large burrow and terminated with the burrowmaker (the latter inferred
from expansion at the end and your nicely jacketed specimen)
2.
Large burrow and terminated with some critter that was not the burrow-
maker
3.
Collapse feature, but with some hapless critter at the end of it that fell into/
drowned in it
4.
Impact structure, with aluminum from the alien spaceship still preserved
(and the spaceship safely concealed from prying eyes of the guvmit [gov-
ernment])
5.
Not enough information, you speculative ichnologist!
I ended my reply with a summary interpretation: “… it would most likely be a
bank burrow(adjacent to a channel) going into a fluvial [river] overbank deposit …
I'll guess that you got a crocodilian at the end of its burrow.”
My thinking at the time was influenced by what I knew about big modern
burrows I had been studying on the Georgia barrier islands, namely alligator dens.
Alligators are represented by two species that live in widely separated places: the
southeastern U.S., which has the American alligator (
Alligator mississippiensis
),
and eastern China, with the Chinese alligator (
Alligator sinensis
). Both are burrow-
ers, especially the Chinese alligators, which dig tunnels as long as 20 m (67 ft) into
soft sediments next to water bodies. The American alligator burrows are not so ex-
tensive,butstillimpressive structures. Thesecanbemorethanameter(3.3ft)wide
at their entrances, are 4 to 6 m (13-20 ft) long, and, like their Chinese relatives, are
made next to ponds or intersect the local water table.
