Upper Ordovician

Upper Ordovician

[′əp·ər ‚ȯr·də′vish·ən]
(geology)
The latest epoch of the Ordovician period of geologic time, beginning approximately 440 million years ago.
References in periodicals archive ?
Disturbance and ecologic succession in an Upper Ordovician cobble-dwelling hardground fauna.
As previously mentioned, the primary target formation of Saturn Minerals exploration program continues to be the Red River Formation, a stratigraphic unit of Upper Ordovician age in the Williston Basin well known for economic pools of oil south of the Potash Restriction Zone, and unexplored north of the Potash Restriction Zone.
Well-drilling exploration has revealed the absence of the Middle Ordovician Yijianfang and Upper Ordovician Tumuxiuke formations in the central Tarim uplift between the Mid-Lower Ordovician Yingshan and the Upper Ordovician Lianglitage formations of the Bachu uplift (Yang et al.
Slightly lower quality frac sand, referred to as "Brady" or "Brown" sand, is mined from central Texas, The principal sources of "Northern White" or "Ottawa" sand in the upper Midwest are the Middle and Upper Ordovician St.
The Palaeozoic succession of the Punta Negra Anticline should display a stratigraphic gap of Upper Ordovician age, as in other parts of the Central Precordillera (Bracaccini, 1949), interpreted as evidence for a peripheral bulge produced in a foreland basin as the result of the collision of the Cuyania terrane with the Gondwana margin (Astini et al.
The deep shelf black shale samples come from the Upper Ordovician Mossen and Fjacka formations and Lower Silurian Dobele Formation (Fm.
Following the pre-fracture stimulation results announced on 3 rd October 2011, the upper Ordovician interval of the AT-8 well was successfully fracture stimulated.
The Serpent Mound central peak is comprised of Upper Ordovician -Middle Silurian carbonates and shales (Reidel 1975).
Later on, due to the sea transgression, the eroded surface was buried under thin (20-300 m) post-impact, Upper Ordovician carbonate deposits and, possibly, subsequent suites destroyed through erosion (Puura & Suuroja 1992; Ainsaar et al.
1991, Environmental cycles and bioevents in the Upper Ordovician Red River-Stony Mountain solitary rugose coral province of North America: Geological Survey of Canada, Paper 909, p.
Upper Ordovician mounds in the Alabama Appalachians are dominated by bryozoans and algae, with bachiopods arid sponges important in some mounds.
Contact relationships indicate that this unconformity is the result of nondeposition of the Upper Ordovician sediments associated with the Queenston Shale and the Big Hill Dolomite due to the presence of a topographic high.

Full browser ?