Bolivia is a landlocked country located in South America with a remarkable fossil record given the country's present day high-altitude mountainous geography. Bolivia’s fossil record tells a story of a transformational prehistoric land once partly submerged by a shallow sea, of delta's and lakes whose shorelines were travelled by many different dinosaurs.
Not unlike the fossil fish, ammonites and crinoids found in the Qomolangma Formation on Mount Everest; the "stone bugs" or Trilobites found in the Canadian Rockies or the sacred Shaligramas or ammonites found along the Kali Gandaki River in the Nepal Himalayas. Bolivia's fossil record is found in the high country.
Bolivia's landscape is today influenced by the geology of Andes Mountains the highest mountain range outside Asia formed between 10 - 6 million years ago. The Andes are a continuous chain of mountain ranges spanning over 7,000 Km from the western edge of South America, from Venezuela all the way along Chile to South America's southern tip, crossing through Ecuador, Peru, and Bolivia.
Among Bolivia's mountain ranges is the Royal Range or Cordillera Real (“Oriental”) on the eastern flank marked by Mount Illimani overlooking La Paz and the Cordillera Occidental on the western flank with Bolivia's highest peak Mount Sajama rising to 6,542 metres only two hours from La Paz the highest capital city in the world.
Both of these peaks are extinct stratovolcanoes forming part of the later Andean Volcanic Arc (AVA) a discontinuous continental-margin on the Altiplano Tectonic Plate Boundary where the Nazca Plate and Antarctica Plates subduct beneath the South America Plate.
At the centre of the Andes is the Bolivian Antiplano a vast a high plateau at over 3,650 meters above sea level. The Antiplano stretches across western Bolivia and into parts of Peru, Chile, and Argentina and is known for its arid plains, salt flats, volcanic landscapes and also known for the last stand staged by the notorious US outlaws Butch Cassidy and the Sundance Kid near the town of Tupiza. The ecosystem of the Altiplano is diverse including flamingos found at the Laguna Colorada or Red Lagoon considered ‘Bolivia’s most incredible natural wonder.’
Though its interesting to understand more about the Andes Mountains its more relevant to consider that the fossil record of Bolivia pre-dates this mountain range back to the Devonian and Silurian periods.
Today in Bolivia, Trilobites can be found at altitudes over 3,700 meters above sea level in the marine sediments and rock formations near to La Paz and dinosaur trackways of theropods and sauropods can be found at a number of locations including Cal Orck’o (derived from Quechua meaning "Cerro de Cal"; in Spanish, "Hill of Limestone").
The Cal Orck’o dinosaur footprints (19º05' S / 65º10' W) are only a short distance from Sucre a historic Spanish colonial town founded in 1538 as a mining town and also the first capital of Bolivia.
Originally known as Ciudad de la Plata de la Nueva Toledo (meaning "Silver Town of New Toledo") the city was renamed in honour of the deceased leader for the fight for Independence, Antonio Jose de Sucre in 1839 and Secure is also the place where the Declaration of Independence from Spain was signed in 1825. The Historic City of Sucre was designated a UNESCO World Heritage Site in 1991.
If Sucre is your base there is a dedicated Dinobus located on Plaza 25 de Mayo esq. that makes the short journey from the Cathedral Basilica of Our Lady of Guadalupe to Parque Cretácico opposite to the Cal Orck’o dinosaur footprints. Described by Lonely Planet as a place with "kitschy life-size models of dinosaurs good for kids and a room with unimpressive fossil displays" the recommendation is to book a guided tour of the quarry and get up close to the dinosaur footprints.
Dinosaur footprints in Bolivia have been known since the 1960's following the discovery of ankylosaurs, theropods and sauropods near to the village of Toro Toro in the Torotoro National Park. It was not until 1994 when a huge vertical limestone wall was uncovered by Bolivian geologist Hugo Heymann during the construction and requirement for cement to build a new highway that started the process of international recognition and public awareness of the country's dinosaur fossil record.
Following the publication of a study of the Cal Orck'o dinosaur footprints in 1998 the area was declared a National Monument and this paper was also instrumental in starting a movement towards putting in place protections of other palaeontological sites across Bolivia.
The Cal Orck’o dinosaur footprints are found within Sucre’s Fabrica Nacional de Cemento SA (Fancesa) a working cement quarry on a huge limestone wall measuring over 1500 meters wide and over 130 meters at its highest point.
How the Cal Orck’o dinosaur footprints were found and presented is in some ways a similar story to many fossil sites around the world. As in this case, road building was also responsible for uncovering dinosaur footprints of Late Jurassic sauropod and theropod dinosaurs near Porrentruy of Switzerland in the Jura Mountains in 2002 when construction started on the Transjurane Highway A16. Also, the Cal Orck’o dinosaur footprints are presented on a vertical wall due to tectonic earth movement much in the same way as the Lower Jurassic Ammonite Wall or Dalle à ammonites of Digne-Les-Bains in the Géoparc de Haute-Provence.
Over 10,000 dinosaur footprints form over 450 individual and distinct trails made by nine different dinosaur species including a trackway left by a baby T-Rex known as "Johnny Walker."
Cal Orck'o Dinosaur Footprints - Images by Hay Kranen & John Martin Perry
The dinosaur tracks at Cal Orck'o are on an almost vertical cliff face of limestone known as the El Molino Formation. This exposure was reorientated during the Andean mountain building event but was once a flat riverbed and lake shoreline.
Dating back 68 million years ago to the Upper Cretaceous the El Molino Formation extended across Bolivia and is connected to the Vilquechico Formation of Peru and the Yacoraite Formation of Argentina and all of which have dinosaur trackways.
The fossil record of the El Molino Formation apart from the dinosaur footprints shows that freshwater animals were present in the form of ostracods, gastropods, turtles, fish and Characeae a freshwater green algae.
There are nine different types of dinosaur tracks of large and smaller theropods, ornithopods, ankylosaurs, sauropods including a Titanosaur with a unique footprint or holotype Ichnotaxan known as Calorckosauripus lazri.
The designation of the name "Lazri" is derived from the Hebrew for "God has helped" and Lazarus is the patron saint of gravediggers. This reference reflects the understanding that primitive Titanosaurs were thought to be extinct in the Late Cretaceous but somehow there are footprints to the contrary.
Sucre maybe off the beaten track but if you are interested in the study of Ichnology the dinosaur tracks of Cal Orck'o rank among other internationally recognised fossil sites. Afterall, where else can you see a trail of small dinosaur footprints flanked by larger ones that are believed to be those of two adult dinosaurs protecting a baby between them - maybe from Johnny Walker?
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