Waucoba Spring Geologic Section


 


Here are two images--same view--of a portion of the classic Late Precambrian through Early Cambrian Waucoba Spring geologic section in Death Valley National Park. In the late 1890's, pioneering geologist/paleontologist Charles D. Walcott (the scientist who discovered the famous Middle Cambrian Burgess Shale fauna of Canada, an assemblage of soft-bodied organisms found nowhere else on Earth except at a locality in China) first measured and described this section, a famous stratigraphic section called the Waucoba Series whose name noted Cambrian expert Allison R. (Pete) Palmer would like to retain in the paleontological nomenclature: see Palmer's paper 1998, "A proposed nomenclature for stages and
series for the Cambrian of Laurentia", Canadian Journal of Earth Science, v. 35, p. 323-328.

The top image shows the topographic expression of the land looking eastward from Waucoba-Saline Valley Road, roughly at the intersection of the path that leads west to Waucoba Spring.  The bottom view has been marked with colored lines in order to more easily demonstrate the geologic contacts between rock formations.  You are looking eastward from Waucoba-Saline Valley Road to a fabulous Lower Cambrian stratigraphic exposure representing most of the Poleta Formation and a portion of the overlying Harkless Formation. In the bottom image, everything to the left of the green line is the lower member of the Poleta Formation, a brownish-orange limestone in which many species of archeocyathids, an extinct, early sponge, have been recovered.  Strata exposed between the green and red lines represent the middle member of the Poleta--a sequence of greenish shale, siltstone and quartzite that yields abundant annelid and arthropod trails, in addition to three kinds of primitive echinoderms and many nicely preserved Olenellid trilobites. Exposures within the blue lines belong to the upper member of the Poleta Formation, a pale gray to bluish limestone that contains rare archeocyathids.  The ridge enclosed by the black lines is the lowermost Harkless Formation, which produces vertical worm borings (Scolithus), annelid and arthropod trails, brachiopods, salterella (an extinct organism of unknown affinities; it may be some kind of early mollusk. Salterella secreted a tusk-shaped test roughly a quarter inch long.), archeocythids and several species of well preserved trilobites.  The prominent peak beneath the yellow lines lies over a mile east of the Waucoba Spring section; it is composed of massive limestones and dolomites representing the Devonian Lost Burro Formation.

Return to Fossils In Death Valley National Park