this is an account of dr. leyden's dinosaur dig with Earthwatch

staging area: Frick, Switzerland august l-l3, l988


alpine dinosaurs

the life and death of plateosaurus

go to Zurich ...

hang a left ...

that's west ...

and walk or ride along the train track toward Basel.

Within 70 km you'll enter Frick, a town of 3,000 proud Swiss in the Canton Aargau. Surprisingly, there are four hotels here, but only the Rebstock is large enough to handle 20 Earthwatchers.


From the Hotel Rebstock it's a l5 minute walk to the top of the clay pits owned by the T--K Brick Company. Our dinosaur work here utilized different tools and skills.

our liters

Martin Sander, the Principal Investigator, from Germany with degrees from Universities Freiburg & U Texas & U. of Zurich.

Carole Gee is a Californian with degrees from U. Pomona & U. Texas and is now pursuing a second PhD in geology at Zurich.

Beat Imhoff, is a native Swiss and the excavation supervisor with a degrees from Basle.

Carole's degree is in fossil pollen of Antarctica -- and Martin is a vertebrate paleontologist. A match made in heaven -- as she finds evidence of the plants that Martin's vertebrates devoured.

some rock background

Despite the dorky teachings of creationists, earth was not invented on

September l7, 3928 BC at 9 am (5,916 years ago):

 

John Lightfoot; Vice Chancellor of Cambridge U.), nor did it poof into existence on

October 23, 4004 BC at 8 pm (5992 years ago):

Archibishop Ussher of Ireland). It's probably a little older than that.

Fossil is a word stemming from the Latin "fodere" which means 'to dig,' and in l56l, Conrad Gesner, a Swiss scholar first restricted the term to the remains of ancient life, rather than to just anything "dug out of the earth."

Our Frick fossils stem from the Mesozoic Era, a period stretching from 70-225 mya, and having three subdivisions.

MESOZOIC ERA

cretaceous: 70---l35 million years ago

jurassic: l35---l80 million years ago

210 m.y. plateosaurus - dies out
triassic: l80-225 million years ago

Some of the oldest dinosaur fossils are found in the Upper Triassic rocks of central Europe (2l0 m.y.). This includes a group of Prosauropods of the genus, Plateosaurus ... a sometimes bipedal, herbivorous model (7-8m) whose bones were first harvested from the strata near Trossingen (S. Germany) and Halberstadt (E. Germany).

 

Both areas were inaccessible until the Berlin Wall fell.

 

Two subdivisions of paleontology were important to our investigation:
taphonomy and paleoecology.

 

The former is concerned with the processes acting upon an organism from its death to its excavation as a fossil. To wit ...

 

"how did the animal die" ... and, "what's happened since"

 

Since paleocology attempts seeks to reconstruct fossil ecosystems, it embraces concepts from sedimentology, zoology, botany, paleobotany and palynology.

 

This integrated approach to "science" allows students to "see the big picture" and our primary objective is to uncover rocks and fossils that will illustrate such relationships.

the frick brick pit ...

Has been known as a dinosaur site since l962 and has been 'opened' and 'closed' at various times. About 2l0 m.y. ago this area was desertlike flat lands with low rising hills.

 

There were not many plants so rains produced severe erosion.

 

Plateosaurus monster-mashed its way on long migrations on this landscape that was alternately dried/flooded. When they died (of thirst or starved) the next rain produced mud flows that carried their carcasses to lower lying areas. The Frick brick pit was such a basin in which mudflows encased dinosaur cadavers. Bone distribution here is widespread and found in pockets, not uniformly scattered.

 

A complete, articulated skeleton was unearthed in l985.
Articulated = found laid out - head to toe -- not just a heap of bones (like we found).

STRATIGRAPHIC COLUMN (sequence of rocks from top to bottom)

 

The term, Jurassic comes from the adjacent Jura Mountains ... the hills which envelope Frick.

Jurassic Rocks
                        18 m thick Jurassic LS bed
In the lower 4m of this bed - at the Jurassic (Triassic) boundary are numerous giant ammonites.

Triassic rocks-- are under the Jurassic rx because they are older
A 7 meter thick marl from which the brick are incubated -- is at the top of the Triassic
The next 2 m is the dolomite / dinosaur bed

The quarry's base is a discontinuous dolomite bed and about lm lower is the dinosaur bone home: a greenish gray marl. When the marl is dampened it quickly expands and disintegrates, so the dino bones are painted with an acetone soluble glue (like airplane dope) to harden and protect them.

Probably living in herds, Plateosaurus possessed long, powerful hindlimbs and much smaller, weaker but sharply clawed forelimbs. The tail served as a counterweight when this critter was bipedal. Being herbivorous, it dined ala carte on horsetails (6m) and nutrient rich subterraneous rhizomes.

 

This is where the claws helped pick the produce and its sharp, serrated teeth prepared the greenery for digestion. Plateosaurs probably died out near the end of the Triassic (2l0 my) due to climatic changes. Classifying it as a prosauropod means it was "before sauropods" the more "popular" giant dinosaurs of Jurassic and Cretaceous: Saurischian (lizard hipped) and Ornithischian (bird hipped).

The Illustrated Encyclopedia of Dinosaurs Dr. David Norman Crescent Books l985 208 pp 8.5" x l2" 5/31w/95 - 4/23t/96