Quaternary lacustrine deposits exist within several valleys in the Valles caldera in northcentral New Mexico . These deposits contain potentially valuable paleoclimatic records . We report OSL ages for a section of unconsolidated Quaternary sediments exposed in the southwest part of Valle Toledo within Valles caldera . The sequence represents the transition over time from lacustrine to fluvial ...

Holliday (1) rejects age-depth models for the Younger Dryas boundary layer (YDB) in Kennett et al. (2), claiming that they are incorrect for several reasons, including age reversals, high age uncertainties, and use of optically stimulated luminescence (OSL) dating. These same claims previously were presented in Meltzer et al. (3) and were discussed and refuted in Kennett et al. (2). These criti...

E. P., set. 23, single woman, worker in a stay factory, was admitted to the Bristol Infirmary, January 10th, 1883, coniplaining of rheumatic pains and weakness. Previous History. Remembered having no previous illnesses. Five months ago, after having got wet several times in going to work and then sitting in her damp clothes, she suffered from pains and swelling in her hands, elbows and shoulder...

Mantling deposits on the Moon are considered to be pyroclastic units emplaced on the lunar surface as a result of explosive fire fountaining. These pyroclastic units are characterized as having low albedos, having smooth fine-textured surfaces, and consisting in part of homogeneous, Febearing volcanic glass and partially crystallized spheres. Mantling units exhibit low returns on depolarized 3....

Porphyry Cu and epithermal deposits are spatially and temporally related to specific volcanic and plutonic rocks emplaced during the formation of long-lived magmatic arcs formed along convergent plate boundaries (e.g., Sillitoe, 1972; Sutherland Brown, 1976; Titley, 1982; Sawkins, 1990; Bissig et al., 2003). Recognizing the presence, types of deposits, and age of the mineralized volcanoplutonic...

Explosive volcanic eruptions, potentially involving large amounts of magmatic and entrained water, are thought to have been very important in the Noachian and Hesperian periods earlier in Mars history, and basaltic plinian eruptions are likely to have occurred throughout martian history. Previous treatments of explosive volcanic plumes on Mars have simply extrapolated plume models for the Earth...

Introduction. The Magellan spacecraft returned hundreds of images of craters, radar-dark halos, and wind features on Venus. It is clear that surficial layers are associated with some of these features; for example, 59 of the craters have parabolic shaped deposits that are thought to be a few centimeters to a meter in thickness [1],[2]. Magellan also revealed about 400 radar dark “splotches” tha...

Porphyry deposits are copper-rich orebodies formed by precipitation of metal sulphides from hydrothermal fluids released from magmatic intrusions that cooled at depth within the Earth's crust. Finding new porphyry deposits is essential because they are our largest source of copper and they also contain other strategic metals including gold and molybdenum. However, the discovery of giant porphyr...

Recent seafloor exploration has shown that volcanic-hosted massive sulfides (VHMS) occur in modern silicic calderas formed by highly explosive eruptions at substantial water depths. Sampling of these has so far been restricted to surficial deposits. Ancient analogs provide a time-integrated view of the structure and fill of deepwater calderas, but constraints on paleo-water depths have previous...

Tephra particles in physically and chemically evolving volcanic plumes and clouds carry soluble sulphate and halide salts to the Earth's surface, ultimately depositing volcanogenic compounds into terrestrial or aquatic environments. Upon leaching of tephra in water, these salts dissolve rapidly. Previous studies have investigated the spatial and temporal variability of tephra leachate compositi...