Coalsack Bluff was the first discovery site in Antarctica for the latest Permian to earliest Triassic reptile Lystrosaurus. This together with discovery of Permian Glossopteris leaves during the heroic age of Antarctic exploration, indicated not only that Antarctica was part of Gondwanaland, but also that Antarctic rocks recorded faunas from the greatest of all mass extinctions at the Permian–T...

The measurement of isotope ratios in sedimentary rocks deposited over geological time can provide key insights to past environmental change over important intervals in the past. However, it is important to be aware that secondary alteration can overprint the original isotopic records. We demonstrate this principle using high-resolution carbon, sulfur, and oxygen isotope measurements in organic ...

Newly discovered xenoliths within Pliocene and Quaternary intermediate volcanic rocks from southern Peru permit examination of lithospheric processes by which thick crust (60–70 km) and high average elevations (3–4 km) resulted within the Altiplano, the second most extensive orogenic plateau on Earth. The most common petrographic groups of xenoliths studied here are igneous or meta-igneous rock...

Rocks exposed west of the Coast Plutonic Complex in southern southeast Alaska form an imbricate thrust belt that overprints the tectonic boundary between two of the largest allochthonous crustal fragments in the North American Cordillera, the Insular and Intermontane composite terranes. In the Alexander terrane (Insular composite terrane), lower Paleozoic metavolcanic and metasedimentary rocks ...

Molecular clock data indicate that the first zygomycetous fungi occurred on Earth during the Precambrian, however, fossil evidence of these organisms has been slow to accumulate. In this paper, the fossil record of the zygomycetous fungi is compiled, with a focus on structurally preserved Carboniferous and Triassic fossils interpreted as zygosporangium-gametangia complexes and resembling those ...

Sedimentologic, stratigraphic, and geochronologic data from strata of early Mesozoic age in the central Mojave block elucidate the paleogeographic and tectonic evolution of the magmatic arc in the southern U.S. Cordillera. A sequence of calcareous siltstone, volcaniclastic conglomerate, tuff, and quartzose sandstone records the transition from shallow-marine rocks of the Fairview Valley Formati...

BACKGROUND Archosauria and their closest relatives, the non-archosaurian archosauriforms, diversified in the Early and Middle Triassic, soon after the end-Permian extinction. This diversification is poorly documented in most Lower and Middle Triassic rock sequences because fossils of early groups of archosauriforms are relatively rare compared to those of other amniotes. The early Middle Triass...

taposed along the north-trending, high-angle Nahlin fault; all three tectonic elements are intruded by the Late Cretaceous Atlin Mountain pluton (Figure 1-19-2). The oldest rocks in the eastern domain are Mississippian to Triassic oceanic; crustal and sedimentary rocks of the Cache Creek Complex. These include ultramafite, basalt, limestone, chert, argillite and wacke, and probably a mixed ultr...