A Magic Circle Called the Solitario, Part 6: Close-up of the Maravillas Chert | Big Bend Ranch State Park, Texas, USA
Detail of the base of the slope shown in my Part 5 photo. The rock hammer was used here just to provide scale.
They're not as contorted as some other strata nearby, but these layers dipping into the hillside do have a slightly undulous look to them, almost like molded brickwork.
While it's officially named the Maravillas Chert, this Upper Ordovician formation does contain, in addition to thin beds of black chert, sandy limestone, marlstone, and shale. In this section, however, the chert predominates.
Portions of the Maravillas suggest that it was formed in part by deep-water avalanches known as turbidity currents, These occurred off the margin of Laurentia, the early-Paleozoic forerunner of modern North America, before this region merged with the South American section of Gondwana to create the Ouachita Mountains.
Among the other places in Trans-Pecos Texas the Maravillas Chert outcrops are the Marathon area and the highly thrust-faulted Persimmon Gap locale, at the northern entrance to Big Bend National Park.
For more on this amazing locale, see the other photos and descriptions in my A Magic Circle Called the Solitario album.
A Magic Circle Called the Solitario, Part 6: Close-up of the Maravillas Chert | Big Bend Ranch State Park, Texas, USA
Detail of the base of the slope shown in my Part 5 photo. The rock hammer was used here just to provide scale.
They're not as contorted as some other strata nearby, but these layers dipping into the hillside do have a slightly undulous look to them, almost like molded brickwork.
While it's officially named the Maravillas Chert, this Upper Ordovician formation does contain, in addition to thin beds of black chert, sandy limestone, marlstone, and shale. In this section, however, the chert predominates.
Portions of the Maravillas suggest that it was formed in part by deep-water avalanches known as turbidity currents, These occurred off the margin of Laurentia, the early-Paleozoic forerunner of modern North America, before this region merged with the South American section of Gondwana to create the Ouachita Mountains.
Among the other places in Trans-Pecos Texas the Maravillas Chert outcrops are the Marathon area and the highly thrust-faulted Persimmon Gap locale, at the northern entrance to Big Bend National Park.
For more on this amazing locale, see the other photos and descriptions in my A Magic Circle Called the Solitario album.