Abstract Precambrian greenstone belts are prospective terrains for orogenic Au deposits worldwide, but the sources of Au, base metals, metalloids, and ligands enriched within still debated. Metamorphic devolatilization is a key mechanism generating Au-rich hydrothermal fluids, respective role metavolcanic metasedimentary rocks present these in releasing ore-forming elements not fully understood...

The Witwatersrand Basin formed over a period of 360 Ma between 3074 and 2714 Ma. Pulses of sedimentation within the sequence and its precursors were episodic, occurring between 3086-3074 Ma (Dominion Group), 2970-2914 Ma (West Rand Group) and 2894-2714 Ma (Central Rand Group). Detritus was derived from a mixed granite-greenstone source of two distinct ages; the first comprises Barberton-type gr...

* Duflo: MIT Department of Economics, 50 Memorial Dr., E52252G, Cambridge, MA 02142 (e-mail: [email protected]); Greenstone: MIT Department of Economics, 50 Memorial Dr., E52-359, Cambridge, MA 02142 (e-mail: [email protected]); Pande: Harvard Kennedy School, Harvard University, Mailbox 46, 79 JFK St., Cambridge, MA 02138 (e-mail: [email protected]); Ryan: Harvard Weatherhead Center, K239 17...

The problems that illiteracy poses in accessing information are gaining attention from the research community. Issues currently being explored include developing an understanding of the barriers to information acquisition experienced by different groups of illiterate information seekers; creating technology, such as software interfaces, that support illiterate users effectively; and tailoring c...

Mobile information systems need to collaborate with each other to provide seamless information access to the user. Information about the user and their context provides the points of contact between the systems. Location is the most basic user context. TIP is a mobile tourist information system that also provides locationbased access to documents in the digital library Greenstone. This paper id...

Several Archean granitoid-greenstone terranes are exposed on the southeastern Kaapvaal craton in South Africa, but they received little scientific attention compared to archetypal greenstone belt successions of Barberton Mountain Land at eastern margin. This study reports a detailed field and geochemical survey Buffalo River Greenstone Belt southern margin KwaZulu-Natal, with focus hitherto uns...

A large anticline structure occurs in the western part of Azov Domain Ukrainian Shield. It is composed rocks Mesoarchean (3.2-3.0 Ga) granite-greenstone association and relics an older basement. The divided into two parts by Bilotserkivka sub-latitudinal strike. northern includes Huliaipole Remivka blocks, southern comprises Saltycha anticline. U-Pb age plagiogneisses Lantsevo 3299 ± 11 Ma. In ...

Digital library technologies have a great deal to offer to creative, design communities. They can enable large collections of text, images, music, video and other information object to be organized and accessed in interesting and diverse ways. Ordinary people – people not traditionally viewed as “creators” or “designers” – can now conceive, assemble, build, and disseminate new information colle...

We consider the problem of updating a digital library collection automatically when certain events occur. Existing digital library systems require the user to either re-build manually or to schedule re-building at specified times. Ideally, a collection should be re-built whenever some collection-changing event occurs. We propose the Event Monitor for Greenstone, a tool that continually tests fo...