New three-dimensional (3-D) Vp and Vp/Vs models are determined for southern California using P and S-P travel times from local earthquakes and controlled sources. These models confirm existing tectonic interpretations and provide new insights into the configuration of geological structures at the Pacific-North America plate boundary. The models extend from the U.S.-Mexico border in the south to...

An assessment performed using raman spectroscopy has found space in the black shales of Cisuralian-age rocks Karoo Basin South Africa, particularly those from Guadalupian Ripon, Cisuralian Whitehill and Prince Albert Formations. It is used conjunction with geochemical screening techniques such as organic petrology programmed pyrolysis. In turn, combination these for thermal maturity sedimentary...

Atmospheric turbulence results taken on the Antarctic plateau are presented in this thesis. Covering two high sites: South Pole and Dome C, this work describes their seeing and meteorological conditions. Using an acoustic sounder to study the turbulence profile of the first kilometre of the atmosphere and a Differential Image Motion Monitor (DIMM) to investigate the integrated seeing we are abl...

High-resolution magnetotelluric and gravity data have been collected over the Kiejo-Mbaka geothermal field, located along NW–SE trending Mabka fault, in Karonga Rift basin (East Africa System). Such resolution allowed to reconstruct field structure with unprecedented detail. Resistivity modelling has obtained by three-dimensional finite-differences inversion of MT data, while density accomplish...

The best ground-based astronomical sites in terms of telescope sensitivity at infrared and submillimeter wavelengths are located on the Antarctic Plateau, where high atmospheric transparency and low sky emission are obtained because of the extremely cold and dry air; these benefits are well characterized at the South Pole station. The relative advantages offered by three potentially superior si...

The photosynthetic production of oxygen in the oceans is thought to have begun by 2.7 billion years ago, several hundred million years before appreciable accumulation of oxygen in the atmosphere. However, the abundance and distribution of dissolved oxygen in the late Archaean oceans is poorly constrained. Here we present geochemical profiles from 2.6to 2.5-billion-year-old black shales from the...

Marketing of non-iodized salt through unconventional distribution channels is one of the factors weakening the national salt iodization program in South Africa. The aim of this study was therefore to quantify the various sources of household salt, and to relate this information to socio-economic status. Questionnaire information was collected by personal interview during home visits from a mult...

Abderaz Formation is one of the Upper Cretaceous formations in the Kopet-Dagh sedimentary basin. A stratigraphic section from the mentioned formation is selected for detailed systematic description with regard to echinoids. Numerous well preserved representatives of the families Mircrasteridae wright, 1857 and Echinocorythidae Lambert, 1920 are described from the Ghaleh-Zoo stratigraphic sectio...

We have developed a 350μm radiometer to perform automated site testing in remote regions of Antarctica. In summer 2000–2001 the instrument operated at Concordia, a new station under construction at Dome C on the Antarctic Plateau. We present the results, and compare them with the atmospheric opacity measured at the South Pole in the same five-week period. During these five weeks, observing cond...