Geochemistry of natural acid rock drainage in the Mt. Evans area, Anaconda-Pintler Range, Montana, USA

This paper investigates natural acid rock drainage in two streams draining either side of Mount Evans, Montana. Bedrock consists of pyrrhotite-bearing schist intruded by granitic dikes and plutons of late Cretaceous to Tertiary age. The headwaters of both streams are moderately acidic (pH < 5.0) and carry elevated loads of dissolved sulfate, aluminum, and other trace metals (Cd, Co, Cu, Mn, Zn) as well as rare earth elements (REE). Copious aluminum precipitates inferred to be hydrobasaluminite coat boulders of both streams as pH rises > 5, with adsorption of copper and REE. Concentrations and loads of dissolved sulfate and trace elements are anomalously high in a small tributary that is sourced by meltwater from a rock glacier. The S-isotope composition of dissolved sulfate in both watersheds is similar to that of pyrrhotite in the meta-sediments, but not molybdenite in late porphyry dikes. Calculations of sulfate flux (i.e., sulfate load divided by surface area) indicate a relatively fast rate of sulfide oxidation in the study area, possibly due to exposure of fresh bedrock in the steep and recently glaciated field area. Overall, the geochemistry of the site suggests the possible presence of a metamorphosed sedimentary-exhalative (SEDEX) deposit, a possibility that is unlikely to be tested by drilling given the proximity of the site to a federal wilderness area. Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issuesSupplementary material:https://doi.org/10.6084/m9.figshare.c.5649850

The Wind-Swept Nautilus, Enigmatic Clastic Pipes, and Toadstool Landforms: Geologic Features of the Paria Plateau

The Colorado Plateau occupies much of the southwestern United States including portions of Arizona, Colorado, Utah, and New Mexico. This region presents unobstructed views from mesa tops, beautifully colored soils, lone standing buttes, and canyons cut thousands of feet deep. The Colorado Plateau represents a well-preserved window into the Earth’s history. Today, the rocks of the Colorado Plateau lie roughly horizontally, as they were deposited hundreds of millions of years ago. The Plateau’s rise has motivated rivers, in their downhill progress, to carve innumerable canyons. These river canyons allow any nature-lover the opportunity to gaze at 100s of millions of years of geologic history. Within the larger Colorado Plateau, the Paria Plateau straddles the Utah and Arizona borders, and includes the Vermilion Cliff s National Monument, the Paria Canyon-Vermilion Cliffs Wilderness Area, and the southern extent of the Grand Staircase Escalante National Monument (GSENM; pre-2018 boundaries). The Paria Plateau is best known for spectacularly colored, wind-sculpted features such as Coyote Buttes and “The Wave,” where vivid colors accent cross-strata resembling a cresting ocean wave. The Plateau is also recognized for the geologically notable Vermilion Cliff s, Buckskin Gulch slot canyon, White Pocket area, and the Paria River Canyon. Although only two, dual-lane highways circumvent the plateau, several wash-boarded gravel and deeply mud-rutted roads allow access to its interior. From these dirt roads, a few sandy, four-wheel drive paths diminish as they extend and branch into the plateau’s interior. Overall, the Paria Plateau is a relatively quiet and little-visited wilderness.

Truancy as an educational wilderness area

The problem of truancy of students in a modern school is a frequent phenomenon that leads to student failures in learnin g. Truancy contributes not only to lowering the student’s performance at school, but also to deepening the existing diffi culties. The article presents related terms of truancy, their typology, determinants and consequences. Based on the results of the research, the scale of this phenomenon was discussed. Methods of preventing school truancy were also proposed.

Diet and brood size in rural and urban Northern Goshawks Accipiter gentilis in southern Finland

The brood size in the Finnish Northern Goshawks seems to be associated with the breeding habitat and the availability of suitable prey. In this study, we examined these relationships in three study areas of different landscape structure in southern Finland, including a recently colonized urban area. The most abundant prey categories found in the food remains of the goshawk included corvids, turdids, columbids, gallinaceous birds, and squirrels. Corvids dominated in the diet samples of all the study areas. The number of turdids and columbids in the samples was significantly higher in both the rural and the urban habitats than in the wilderness area. The number of gallinaceous birds was significantly higher in the wilderness area than in other habitats. Gallinaceous birds, particularly tetraonids, the traditional staple food of the Northern Goshawk in Finland, seemed to be largely compensated by corvids in the wilderness area and by corvids and columbids in the rural and urban areas. The amount of corvids in prey showed a positive relationship with brood size, suggesting some particular importance of this prey in the goshawk diet. In all, diet seemed to explain partly between-landscape variations in the brood size of the goshawk. The brood size was significantly higher in the urban landscape than elsewhere.