(Table 1) Sulphur concentration and isotopic composition of ODP Leg 126 igneous rocks

Sulfur isotope ratios have been determined in 19 selected igneous rocks from Leg 126. The d34S of the analyzed rocks ranges from -0.1 â to +19.60 â. The overall variation in sulfur isotope composition of the rocks is caused by varying degrees of seawater alteration. Most of the samples are altered by seawater and only five of them are considered to have maintained their magmatic sulfur isotope composition. These samples are all from the backarc sites and have d34S values varying from +0.2 â to +1.6 â, of which the high d34S values suggest that the earliest magmas in the rift are more arc-like in their sulfur isotope composition than the later magmas. The d34S values from the forearc sites are similar to or heavier than the sulfur isotope composition of the present arc

Chemical Composition of Precipitation and River Water in Southern Iceland: Effects of Eyjafjallajökull Volcanic Eruptions and Geothermal Power Plants.

AbstractSamples of precipitation have been collected and analysed from four sampling stations in southern Iceland. Sea-salt in the precipitation has the same elemental ratios as in seawater and its concentration decreases with distance from the shore. The sampling station at Mjóanes, at Thingvallavatn Lake, is located around 100km west of Eyjafjallajökull and during and after its eruption in 2010, the concentration of fluoride in precipitation increased from 10-20μg/l to 90μg/l and the annual average concentration elevated from 11μg/l to 28μg/l. From 1980 to 1998, pH of rainwater at Írafoss increased due to emissions reductions of anthropogenic sulphur. Since 1998, pH of the precipitation has decreased again at Írafoss. Similar pH changes are seen in Mjóanes, which is close to Írafoss, but not in other sampling stations further away. River water samples collected in the vicinity of the rainwater samplers, from the spring fed river Sog have elevated non-SO4 sulphur concentration from 2005-2010 and decreased δ34S from 2005-2007. Írafoss and Mjóanes are located approximately 12-20km away from two geothermal power plants, Nesjavellir- and Hellisheidi power plants that emit large quantities of CO2 and H2S, among other gases, to the atmosphere. The data presented here suggest that geothermal power production can cause local environmental effects, like rainwater acidification and increases in dissolved sulphur in rivers in the vicinity of the power plants

Late glacial and Holocene palaeoenvironmental changes in the Rostov-Yaroslavl area, West Central Russia

Abstract Three lake sediment sequences (lakes Nero, Chashnitsy, Zaozer'e) from the Rostov-Jaroslavl' region north of Moscow were studied to provide information on palaeoclimatic and palaeoenvironmental changes during the past 15,000 cal yr. The multi-proxy study (i.e., pollen, macrofossils, mineral magnetic measurements, total carbon, nitrogen and sulphur) is chronologically constrained by AMS 14 C measurements

Stable isotope measurements along the rivers Malaya Kuonamka and Bol'shaya Kuonamka in Siberia

Carbon isotopic oscillations are useful to elucidate the stratigraphy and biogeochemical events around the Precambrian-Cambrian transition. New isotopic data from the Manykaj and Emyaksin formations of the eastern Anabar Uplift (Siberia) help to correlate the Lower Cambrian and Neoproterozoic-Cambrian transitional beds across the Siberian Platform. The similarity of trends and amplitudes of the carbon isotopic curves, together with biostratigraphic and sequence-stratigraphic markers from the Anabar Uplift,provide a precise correlation with the southern part of the Siberian Platform. Diagenesis of argillaceous limestones of the Emyaksin Formation has apparently not affected the primary isotopic variations. The resulting curve is nearly identical in sections about 100km apart in the Tommotian-Atdabanian portion ofthe formation.Relatively frequent and pronounced isotopic oscillations in the lower beds of the Emyaksin Formation fit between features I and II of the southern Siberian isotopic reference scale but are undetected therein owing to the depositional hiatus at the base of the Tommotian Stage in its type section. This cofirms the transgressive onlap from the north suggested by previous studies,and makes the appearance of the Cambrian skeletal fossils on the Siberian Platform less abrupt.The hiatus in the south appears to embrace at least two biostratigraphic zones as recognized in the north. The case is strengthened for a pre-Tommotian Cambrian Stage in Siberia,the biostratigraphic framework for which has been elaborated earlier