Ethynyl Around the HII Regions S255 and S257

Astronomy Reports - We present the results of the ethynyl (C2H) emission line observations towards the S255 and S257 HII regions and the molecular cloud between them. Radial profiles of line...     

The MASTER-II network of robotic optical telescopes. First results

The main stages in the creation of the Russian segment of the MASTER network of robotic telescopes is described. This network is designed for studies of the prompt optical emission of gammaray bursts (GRBs; optical emission synchronous with the gamma-ray radiation) and surveys of the sky aimed at discovering uncataloged objects and photometric studies for various programs. The first results obtained by the network, during its construction and immediately after its completion in December 2010, are presented. Eighty-nine alert pointings at GRBs (in most cases, being the first ground telescopes to point at the GRBs) were made from September 2006 through July 2011. The MASTER network holds first place in the world in terms of the total number of first pointings, and currently more than half of first pointings at GRBs by ground telescopes are made by the MASTER network. Photometric light curves of GRB 091020, GRB 091127, GRB 100901A, GRB 100906A, GRB 10925A, GRB 110106A, GRB 110422A, and GRB 110530A are presented. It is especially important that prompt emission was observed for GRB 100901A and GRB 100906A, and thar GRB 091127, GRB 110422A, and GRB 110106A were observed from the first seconds in two polarizations. Very-wide-field cameras carried out synchronous observations of the prompt emission of GRB 081102, GRB 081130B, GRB 090305B, GRB 090320B, GRB 090328, and GRB 090424. Discoveries of Type Ia supernovae are ongoing (among them the brightest supernova in 2009): 2008gy, 2009nr, 2010V, and others. In all, photometry of 387 supernovae has been carried out, 43 of which were either discovered or first observed with MASTER telescopes; more than half of these are Type Ia supernovae. Photometric studies of the open clusters NGC 7129 and NGC 7142 have been conducted, leading to the discovery of 38 variable stars. Sixty-nine optical transients have been discovered.     

Supergene transformed naphthides: Peculiarities of trace-element composition

Available data on the transformation of naphthides (oils and bitumens) in various petroleum basins (PB) during supergene processes were generalized to reveal their characteristic features for more accurate prediction of pool preservation and commercial quality of oils as hydrocarbon raw material enriched in economically significant toxic metals. Using petroleum basins of the United States, Canada, Brazil, Venezuela, Nigeria, Russia, Kazakhstan, and Turkmenia as examples, itwas demonstrated that trace-element concentrations and ratios as well as metalloporphyrin complexes (MPC), including vanadium (Vp) and nickel (Nip) ones, which are associated with heavy resinous-asphaltene components of oils, serve as geochemical criteria of supergene transformed fluids. During supergenesis, oils show differential enrichment in metals. Considerable enrichment in V, Ni, Co, Mo, Cr, and other trace elements as well as MPC were found in oils generated by sapropel organic matter (OM) and initially enriched in metals (deposits of the South Tatar arch of the Volga-Urals, Buzachi arch, Afghan-Tajik Basin, and Marakaibo petroleum province of Venezuela). Oils initially depleted in trace elements and usually generated by humic OM also show increase in trace elements, but their concentrations are 1–3 orders of magnitude lower than those in enriched oils (oil fields in the coastal basins of Nigeria and Brazil). It was shown that supergene transformed fluids are well deciphered on the basis of a complex use of hydrocarbon and trace element criteria.     

Trace Elements in Naphthides in Oil and Gas Basins

Doklady Earth Sciences - The distribution of trace elements, physical and chemical properties of the oil, and geological and geochemical features of oil formation in world oil and gas basins were...     

The relative role of lower and upper crustal processes in the formation of trace element compositions of oils

This study presents the analysis of correlation between trace element compositions of caustobioliths (oils, coals, oil and black shales), upper and lower continental crust, and living matter. It was shown that trace element concentrations in coals and oil shales have the better correlation with the upper crustal values, whereas trace elements in oils correlate well with the lower crustal values. The statistically significant, yet poorer correlation was observed for trace element compositions of oils and living matter as compared to correlations between oils and lower crust. The results suggest that oils are compositionally more homogeneous on a basin scale and possibly have more heterogeneous composition in different petroleum basins. A suite of characteristic trace elements (Cs, Rb, K, U, V, Cr, and Ni) that was used for analysis allowed a consistent interpretation of the relative upper and lower crustal contributions to the trace element composition of oils.