Early Archean tonalite gneiss in the upper peninsula of Michigan

Geochronological results on tonalite gneiss of northern Michigan that is 3.56 Ga or slightly older is presented. Tonalitic augen gneiss and structurally overlying biotite gneiss and schist are exposed in a dome near Watersmeet. They are part of an extensive gneiss terrane of southern Minnesota, Wisconsin and Michigan that includes rocks of early to late Archean ages and lies south of the Wawa volcanic subprovince. Two samples of the augen gneiss and one of the biotite gneiss show zircon grains of similar shape, zoning, color, and development of crystal faces. These zircons give Pb/U isotopic ratios that plot on a chord of 3,560 + or - 40 m.y. upper intersect and of 1,250 + or m.y. lower intersect. The 3,560 m.y. number is believed to be a minimum age because analysis of one of the least discordant zircon fractions by ion microprobe that gave a nearly concordant age of 3,650 m.y. The 1,250 m.y. lower intersect is without geological significance: it is interpreted to be a result of multiple lead loss at 2.7, 1.8, and 0.5 Ga by U/Pb in zircon. Archean rocks 10 to 25 km northwest of the Watersmeet dome give a 2.75 Ga age on zircons. Quartz monzonite here is dated at 2.65 Ga

A University Course on Management Intensive Grazing

Education of new talent in good grassland management is important. Farmer-oriented extension- and outreach- programs do this, but USA university curricula rarely include it. Some livestock production courses contain a segment on grazing management, but there seem to be no credit-bearing, formal courses in USA universities except in the Ohio State University (OSU). Our course teaches management of intensive grazing (MIG) for three credit hours in a quarter system. It has been a popular elective course for the past 6 years. Every year that they have entered, OSU students have won all prizes in the 18-22 age division in the American Forage and Grassland Council and the Ohio Forage and Grassland Council essay competitions. This proves the students\u27 knowledge. On graduation, students often move to professional positions or production agriculture, where they can apply the skills learned. Members of Ohio organizations and government agencies, who are concerned about the environment and family farm survival, enthusiastically support the course

Negotiating International Regimes: Lessons Learned from the United Nations Conference on Environment and Development (UNCED)

The UN Conference on Environment and Development (UNCED) produced above all the beginning of a new process, rather than arriving at a singular and conclusive agreement to a specific problem - often the more common outcome of negotiation. Whereas outwardly the UNCED process was familiar, it soon was to distinguish itself as a singularly instructive set of "regime-building" negotiations. This important new work, developed by IIASA, explains and analyses the negotiation process of building international environmental regimes. Its value will be considerable as the international community faces the need to establish the variety of sub-regimes (desertification, forestry, and others) spawned by UNCED. This work offers the conceptual and practical building blocks, as learned from UNCED, to all those engaged, and interested in the means to ensure sustainable development and the economic and environmental well-being of humanity. The text is accompanied by valuable appendices