Geoscience Reference
In-Depth Information
the other side of the hill. Sure enough, the same track bed was there, just where Dr.
Tedfordpredicteditwouldoccur.Thustheentiretrack-bearing bedwaslikelymore
extensive than originally surmised, and would need to be excavated before it could
be investigated in detail.
This is all well and good, but still does not tell how the track-site gained
its current nickname of “Lark Quarry.” When paleontologists from the University
of Queensland and Queensland Museum—Drs. Tony Thulborn and Mary
Wade—decided to study the site in the mid-1970s, one of their most dedicated vo-
lunteerswasMalcolmLark,alocalresident.Accordingly,theynamedthesiteinhis
honor. The “quarry” part of its moniker came from what these paleontologists and
volunteersdidduringthefieldseasonsof1976and1977.Inordertoexposeandsee
more of the track-bearing surface, they had to strip off a 30-cm (12-in) thick sand-
stone bed overlying the tracks. By the time they finished, these industrious folks
estimated that they'd moved more than 50 tons of rock, which revealed an area of
210m
2
(2,250ft
2
)holdingmorethan3,300dinosaurtracks.Thiswasahard-earned
mother lode of dinosaur trace fossils.
You might think that such a concentration of dinosaur tracks—on average
about 15 tracks per square meter—would be enough in itself to guarantee everlast-
ing paleontological fame. But it got even better. Once the surface was cleared of
its overburden and its tracks could be mapped and described in detail, a remark-
able story came to life. And storytelling is what ichnology is all about, and why
it is probably among the oldest sciences known to humankind. Moreover, science
ideally should surprise us, and these tracks certainly astonished the original invest-
igators, along with succeeding generations of paleontologists and the public after-
wards.
Based on Thulborn and Wade's analysis of the site, the area was a lakeshore
thathadbeensubmergedregularlybyanearbystreamemptyingintoit.Fluctuations
between submergence and emergence of the shoreline could be discerned from al-
ternating sand and mud layers in the rock, as well as long parallel grooves caused
