d'Almeida G.A.F.,Russian State Geological Prospecting University
Geotectonics | Year: 2010
The Red Sea Rift has been an object of comprehensive studies by several generations of geologists and geophysicists. Many publications and open-file reports provide insights into the geological history of this rift. Paleogene and Cretaceous rocks, which are considered to be prerift, are locally exposed at the margins of the Red Sea Rift. At the same time, some evidence indicates that at least some of these rocks are related to the early stage of the evolution of the Red Sea Rift. The available geological data suggest that the Red Sea region started its active evolution in the Cretaceous. As follows from lithostratigraphic data, the Cretaceous-Paleogene trough that predated the Oligocene-Quaternary rift covered this region completely or partially. The pre-Oligocene magmatism and geological evidence show that the Cretaceous-Paleogene trough was of the rift type. The Cretaceous-Eocene and Oligocene-Quaternary phases of rifting were separated by an epoch of uplifting and denudation documented by the erosion surface and unconformity. © 2010 Pleiades Publishing, Ltd.
Maria K.,Russian State Geological Prospecting University
Proceedings - SPE Annual Technical Conference and Exhibition | Year: 2011
The report focuses on the results of simulation of the near-well area heating by an electric current and the substantiation of using an electric field as a thermal method of oil production intensification. We give the description of such programs as NKAR (the program of the numerical solution of the direct problem of electrical logging), THERM3C (the program of solving the direct three-dimensional problem of thermometry) which were used in the simulation.
Bolonin A.V.,RAS Institute of Geology and Mineralogy |
Gradovsky I.F.,Russian State Geological Prospecting University
Geology of Ore Deposits | Year: 2012
The Ordovician-Lower Carboniferous sequence of slightly metamorphosed gray carbonate-terrigenous rocks contains the Silurian black cherty shales enriched in carbon (6-9%), pyrite (6-7%), and uranium (~30 ppm). The uranium ore is localized at the pinch-out of areal and linear zones of the Early Permian supergene (exogenic) oxidation of rocks expressed in reddening (hematitization). U, As, Sb, Cu, Ni, Mo, and Ag have been removed from the oxidized black shales and concentrated in the cementation zone in form of pitchblende and sulfides in wall-rock disseminations and veinlets largely hosted in carbonate-bearing rocks. In the Late Permian, during deposition of the upper Rotliegende and Zechstein, the fractures in the basement were filled with carbonates and sulfates; uranium was partly redeposited along with enrichment in Pb and Zn. Mesozoic and Cenozoic supergene processes altered uranium ore insignificantly. © 2012 Pleiades Publishing, Ltd.
Lyubushin A.A.,Russian Academy of Sciences |
Yakovlev P.V.,Russian State Geological Prospecting University
Izvestiya, Physics of the Solid Earth | Year: 2016
A new method for estimating the stepwise component in the time series is suggested. The method is based on the application of a pseudo-derivative. The advantage of this method lies in the simplicity of its practical implementation compared to the more common methods for identifying the peculiarities in the time series against the noise. The need for automatic detection of the jumps in the noised signal and for introducing a quantitative measure of a stepwise behavior of the signal arises in the problems of the GPS time series analysis. The interest in the jumps in the mean level of the GPS signal is associated with the fact that they may reflect the typical earthquakes or the so-called silent earthquakes. In this paper, we offer the criteria for quantifying the degree of the stepwise behavior of the noised time series. These criteria are based on calculating the entropy for the auxiliary series of averaged stepwise approximations, which are constructed with the use of pseudo-derivatives. © 2016, Pleiades Publishing, Ltd.
Sadovnikov G.N.,Russian State Geological Prospecting University
Paleontological Journal | Year: 2015
The formation of the Middle Siberian Traps has been considered one of the main causes for the change in the biota at the Permian-Triassic boundary. At the first stage of the formation of the volcanic plateau (Lebedevskian time), volcanism was dominated by tuffs; at the second stage (Khungtukunian time), by tuffs and lavas; and at the last stage (Putoranian time), by flood basalts. The paper presents a paleoecological characterization of the plateau at the middle (Khungtukunian) stage, immediately before the Permian-Triassic boundary (ammonoid standard). At the beginning of this stage the plateau reached an altitude of about 500 m above sea level, at the end of the stage it was higher than 800 m above sea level (Sadovnikov and Turlova, 2004). The Khungtukunian deposits have yielded more than 230 species, belonging to more than 70 genera of plants, conchostracans, ostracods, bivalves, and fishes. © 2015, Pleiades Publishing, Ltd.