Sino - KU Expedition
- 2006 -
Sino -
KU Expedition
- 2006 -
In August of 2006, I was invited by
Dr. Luis González of the
University of Kansas and
Dr.
Greg Ludvigson of the Kansas Geological Survey to participate in an
NSF-funded expedition to investigate three Lower Cretaceous terrestrial
sequences in
Gansu Province, China. We
were invited by Dr. Hai-lu You, a
Research Scientist with the Chinese Academy of Geological Sciences, Beijing,
to examine the paleoclimatology and paleoecology of dinosaur-bearing
sequences and to constrain the age of these deposits using stable isotope
chemostratigraphy. I participated in measuring sections, describing
lithologies, and collecting samples for isotopic analysis. In
addition, Brian Platt and myself conducted a preliminary survey of
ichnofossils and paleosols in fluvial, alluvial, and lacustrine deposits in
all three terrestrial sequences. The continental ichnology and paleopedology
of these and other continental Phanerozoic deposits in China are virtually
undescribed. We hopefully will be able to accept the open invitation
extended by our gracious hosts, Dr. You and his Chinese colleagues, to
return to China and expand this preliminary work into the hidden
biodiversity and paleohydrology of these deposits.
The Liujiaxia Dinosaur State Geological Park
exhibition hall, which opened to the public in 2005, was built to
protect and display dinosaur footprints discovered at the site in 1999.
Sino-KU expedition crew measuring and describing
Barremian to Albian age fluvial deposits in the Hekou Formation, Lanhzou
Basin. The Yellow River can be seen in the background.
KU graduate students get an up-close look at the
trackways on display and the skeletal reconstruction of
Lanzhousaurus
magnidens,
a locally discovered Lower Cretaceous ornithopod with surprising large
teeth.
Invertebrate trace fossils were abundant in thin beds
of muddy fine-grained sandstone and consisted mostly of cylindrical
vertical and horizontal sand-filled burrows, backfilled burrows and
large sinuous burrows.
Here I am following my true calling, ditch digger.
We excavated several measured sections through fossil-bearing paleosols
and fluvial deposits.
Without a spot of shade in the field, heat-stroke is
a real concern and mid-day breaks are essential, at least for
over-weight and unacclimatized westerners like myself (above). Seriously
though, it was hot.
A thoroughly bioturbated block of sandstone from the
Zhonggou Formation containing large diameter, horizontal and vertical
sand-filled burrows. Trace fossils appeared to increase in
abundance and diversity with increasing evidence of paleopedogenic
development up-section in these strata .
An audience gathers while I photograph trace fossils.
I think the children were more puzzled by my behavior than fascinated by
the burrows I collected. They were, however, very entertained by
my attempt to explain what they were.
Deposits ranged from mostly thick beds of massive
sandstone to thin beds of muddy sandstone to mudstone. Trace
fossils were most common in the thin, finer-grained deposits, including
a possible trackway in the picture above.
Theropod, ornithopod, and exceptionally large
sauropod trackways, as well as pterodactyl and bird tracks represent the
first significant discovery of Mesozoic vertebrate ichnofossils in the
Gansu Province.
The KU Cretaceous Research Group, from left to right
in the back: Dr. Greg Ludvigson, Dr. Luis González, graduate students
Emily Tremain, Brian Platt, and Aisha Al-Suwaidi; and front: graduate
students Marina Suarez, Celina Suarez, Rebecca Totten, and yours truly.
A trace fossil-rich zone in fluvial and overbank
deposits of the Zhonggou Formation, Changma Basin, has my full
attention. Dr. You described an early ornithuran bird,
Gansus yumenensis, from the underlying Xiagou Formation in 2005.
Most fine-grained units contained pedogenic features
such as mottles (pictured), carbonate rhizoliths, and burrows,
indicating these are ancient soils. Mottles form via the reduction
and mobilization of Fe oxides along soil channels, usually in the
presence of organic matter.
Chinese paleontologists and their
crews spend several months of the year exploring these bone-rich
deposits, something that few American researchers can monetarily or
time-wise afford to do. They were gracious enough to put up with
us for five days.
