the sorkheh deposit in northwestern iran exhibits several readily visible general characteristics of sediment-hosted stratiform copper (ssc) mineralization. it consists of fine-grained disseminated base-metal sulfides within gray sandstones (gray beds, the basal whitish miocene sandstone and shallow-water) that overlie a thick sequence of red beds (miocene upper red formation). the host gray be...

A Permian bentonite deposit at Melo, Uruguay is composed of a calcite-cemented sandstone containing clay pseudomorphs of glass shards (0-0.50 m) overlying a pink massive clay deposit (0.50-2.10 m). The massive bed is composed of two layers containing quartz and smectite or pure smectite respectively. The smectite is remarkably homogeneous throughout the profile: it is a complex mixed layer comp...

Uranium (U) concentration and the activities of 238U, 234U, and 230Th were determined for groundwaters, spring waters, and lake water collected from the Shihongtan sandstone-hosted U ore district and in the surrounding area, NW China. The results show that the groundwaters from the oxidizing aquifer with high dissolved oxygen concentration (O2) and oxidation-reduction potential (Eh) are enriche...

Sandstone intrusions have always caught the attention of geologists and are in many cases highly spectacular due to the contrast between light-coloured intrusive sandstones and dark host mudstones. In recent years it has become increasingly clear, that large, irregular bodies of massive sandstone may also be of intrusive origin, but the timing and nature of remobilization of the primary deposit...

Brand and Tang (1991) proposed that certain unusual vertebrate trackways "point to subaqueous deposition for at least part of the Coconino Sandstone." They supported their conclusions by demonstrating that western newts produce similar trackway configurations in aquarium experiments. While it is encouraging to see vertebrate ichnology play such a prominent role in fundamental questions concerni...

On April 26, 1996, Public Law 104-134 was Chart 1 .-Payment volume, by type of disbursement, fiscal year 1997 enacted, requiring all Federal payments except tax refunds be issued electronically by January 2, 1999, thus beginning a new era in electronic N Federal tax 10.5% funds transfer (EFT). This legislation, the Debt Collection Improvement Act of 1996-part of the Omnibus Consolidated Resciss...

The Pierre Shale is a marine deposit that accumulated in the Cretaceous Western Interior Seaway during the onset of Laramide tectonism in the southern Rocky Mountains region. In the eastern part of the Raton Basin near Trinidad, Colorado, ammonite biostratigraphy suggests that the base of the Pierre Shale lies within or slightly above the Lower Campanian Scaphites hippocrepis III ammonite range...

The facies distribution and palaeobotanical identity of fossil charcoal is described from the Upper Carboniferous (Westphalian A–B) Joggins section, Nova Scotia, in order to examine the fire ecology of early Westphalian floodplains. Three charcoal assemblages are noted. Assemblage (1) consists of channel sandstone bodies, containing beds of calcrete breccia, cordaite logs (up to 3 m long), and ...