The Cretaceous Western Interior Seaway Drilling Project was begun in 1991 under the auspices of the U.S. Continental Scientific Drilling Program. It was intended to be a multidisciplinary study of Cretaceous carbonate and silicicl.tic rocks in cores from bore holes along a transect across the Cretaceous Western Interior Seaway. The study focuses on middle Cretaceous (Cenomanian to Campanian) st...

To geologists, the Ordovician System of Ohio is probably the most famous of the state's Paleozoic rock systems. The alternating shales and limestones of the upper part of this system crop out in southwestern Ohio in the Cincinnati region and yield an incredible abundance and diversity of well-preserved fossils. Representatives of this fauna reside in museums and private collections throughout t...

this paper presents the new geochemical isotopes sr and nd, and the mineralization data for the south neyshabour volcanic rocks located in ne iran. based on the chemical classifications, the studied rocks are basaltic trachy andesite, trachy andesite, trachyte, and trachy dacite in composition. all the analyzed volcanic rocks display enrichment in light rare earth elements (lree) relative to th...

Using a recent compilation of African alkaline igneous rocks and carbonatites, we show that nearly 90% (28 of 32 occurrences) of nepheline syenite gneisses and deformed carbonatites are concentrated within known or inferred Proterozoic suture zones. Given the wellestablished intracontinental rift setting for these rocks and the likely continental collisional setting for their subsequent deforma...

Although the source layer for marine magnetic anomalies has been assumed to be the extrusive basalts of uppermost ocean crust, recent studies indicate that lower crustal rocks may also contribute. Because the temperature at which magnetization of crustal rocks achieves long-term stability is crucial to any source layer contribution, we undertook hightemperature VRM (viscous remanent magnetizati...

Bimodal volcanism in the Santa Maria Province of west-central California occurred when segments of the East Pacific Rise interacted with a subduction zone along the California margin during the Early Miocene (about 17 million years ago). Isotopic compositions of neodymium and strontium as well as trace-element data indicate that these volcanic rocks were derived from a depleted-mantle (mid-ocea...

Age Determination 105038 Kawano, Y. & Yuhara, M. Chronological and isotope geological study of Cretaceous granitic rocks, upper reach of the Nakagawa river, Fukuoka Prefecture. J. Geol. Soc. Japan, 114, 218-230, 8 figs., 2 tables (in Japanese with English abstract), 2008. Cretaceous granitic rocks, consisting of Itoshima granodiorite and Sawara granite, are occurred at upper reach of the Nakaga...

The central Oregon section of the Cascade Range volcanic arc is characterized byrelatively high Quaternary volcanic extrusion rates and hot-spring discharge rates, and by high conductive h at flow. However, a large area of near-zero near-surface onductive h at flow occurs in the younger volcanic rocks, due to downward and lateral flow of cold groundwater. Alternate models for the high heat flow...

Low-molecular-weight hydrocarbons in natural hydrothermal fluids have been attributed to abiogenic production by Fischer-Tropsch type (FTT) reactions, although clear evidence for such a process has been elusive. Here, we present concentration, and stable and radiocarbon isotope, data from hydrocarbons dissolved in hydrogen-rich fluids venting at the ultramafic-hosted Lost City Hydrothermal Fiel...