Measurement of natural stresses in a Provence mine (Southern France)

Stress measurements were carried out in the Arc syncline using drifs in a lignite mine. Eleven sites were investigated using the flat jack and hydraulic fracturing (or stimulating) methods. Two stress states were found to coexist, one isotropic, the other highly anisotropic. The orientations of the principal stresses are not homogeneous and an orientation ranging from E-W to NE-SW predominates locally. This does not accord with the regional stress field. The vertical stresses are systematically underestimated.     

Stability analysis of lateritic waste deposits

In open-pit mines covered with lateritic soil, the sterile ground is stored in specially prepared sites. The waste area must then be enhanced in order to extend storage capacity.

To better understand the effect of an elevated dump, typical laboratory tests (triaxial and oedometer tests) have been performed on the lateritic material. The waste disposal site has been modeled using both limit equilibrium and finite element methods. Different types of finite element models have been run; they take the variation of Young's modulus with depth into account and simulate the effect of construction over various phases. Modeling results are then compared with in situ measurements.     

The 1928–1929 eruption of Kammourta volcano — evidence of tectono-magmatic activity in the Manda-Inakir rift and comparison with the Asal Rift,Afar depression,Republic of Djibuti

There are two rifts zones in the Republic of Djibuti: the active Asal rift (birthplace of the Ardoukôba basaltic volcano in 1978) and the poorly known Manda-Inakir rift described here. The most recent volcanic event in the Manda-Inakir rift was the formation of the Kammourta basaltic cone, probably in 1928, accompanied by strong seismic activity. This historic eruption and related tectonic features show that the Manda-Inakir rift, like Asal, is presently active. The Kammourta basalt, of transitional alkaline type, belongs to the Manda-Inakir differentiated series, which ranges from basalt to rhyolite. In contrast, volcanic rocks of the Asal rift are entirely transitional tholeiitic basalt. The differences in magmatic affinity and tectonics between these two rift zones reflect the more advanced evolution of rifting in the Asal zone than in Manda-Inakir.     

Observed climate variability and change in Urmia Lake Basin, Iran

This paper analyzes climate variability and change in the Urmia Lake Basin, northwest of Iran. Annual average of the following data time series has been analyzed by statistical methods: dry bulb temperature, maximum and minimum temperature, precipitation, and number of rainy and snowy days. We have also used mean monthly temperature and precipitation data for analysis of drought spells for the period 1964–2005 to find out whether fluctuations in the lake level are attributable to natural drought. Our results indicate that mean precipitation has decreased by 9.2 % and the average maximum temperature has increased by 0.8°C over these four decades. The seasonal changes are particularly visible in winter and spring. Results of the Palmer Drought Severity Index show that on average, drought episodes have hit the Urmia Lake Basin every 5 years and most of them reached severe levels, but recent droughts have become more intense and last longer.