Exploration. Geology and Geophysics
PROSPECTS OF CARBONACEOUS DEPOSITS IN THE CENTRAL PART ZAURALSK ELEVATION ON PRECIOUS AND RARE METALS
This paper considers the geological structure of the Troitsk area, located in the central part Zauralsk elevation. Particular attention is paid gorodyshchens’k, alexeyev, chulaksay suites potapovsk and komsomol strata within which developed carbonaceous deposits, as well as chebarkulsk-kazbaevsk and gabbro-ultramafic druzhninsk complexes. All of them have been tested for gold, silver, platinum, palladium, tungsten and molybdenum. Found that in the black shale formations gorodyshchens’k suite in the creek Osipovskiy Log present gold content up to 27 g/t, platinum – 0.75 g/t to mark the highly dislocated, and sulfidized silicified rocks penetrated by dykes gabbros. At 7 km to the north along stretch in the suite aboard river Sanarka in carbonaceous sediments intruded by dikes plagiogranites, set the gold content up to 7.7 g/t, platinum – 0.57 g/t, suggesting the presence here of a single zone of gold – platinum mineralization and recommend it for further exploration and evaluation project. Osipovsk manifestation of gold and platinum is the first object identified among carbonaceous deposits Zauralsk elevation.
The research works indicate a very high perspective on the invention in gorodyshchensk and alexeyev suites gold – platinum, and in potapovsky suitet tungsten mineralization. Host rocks of Nizhnesanarsky granite massif, largely represented by carbonaceous deposits, riched by igneous rocks of different composition and age and survivored by moderate metamorphism, are the primary object for prospecting. The similar situation was noted by us on a number of manifestations of the southern Urals, in particular within Mayardaksky and Yamantausky anticlinoria and carbonaceous shales of Western framing Suunduksky granite massif.
The article on the basis of previous analysis of the development in time of the thermal field granitoid massifs of the Northern part of the East-Ural trough, an attempt is made to estimate the ore content of rocks developed in the frame of the considered Intrusive bodies. At the beginning of the common characteristics of metallogeny of the field presented several ore formations, some of which are connected with the formation of granitoid massifs. It is shown that the problem of forecasting prospects for the discovery of new ore deposits is to establish the factors of localization of ore. In areas with well-developed granitoid magmatism such factor is the isothermal zone of stabilization, thermal field which has remained unchanged for a long period comparable to the period of crystallization of the intrusion of the time interval. The duration of the stabilization temperature provides not only stability of chemical reactions, but also the formation of fracture zones, which are the migration zones of ore-bearing solutions. In the initial moments of the formation of Intrusive bodies such zones occur in the near-contact places.
From this point of view the greatest prospects for rare and noble metals mineralization within the Northern part of the East-Ural trough have: southwest exocontact Kamensky, east exocontact of Central, eastern contact of Plastovsky and Koelginsky massifs, as well as carbonaceous deposits, widely developed in the north-eastern flank of the last of them. Of particular interest are close to the massifs of the first and second places which are promising in the search for high-temperature mineralization (molybdenum, tungsten). Away from the intrusions contact you can expect less high-temperature ore, which can then be replaced by polymetals.
THE SELECTION OF COMPLEX RESERVOIRS OF HYDROCARBONS OPENED ON SALINE FLUSH DRILLING FLUIDS IN DEEP EXPLORATORY WELLS
We have investigated the usefulness of GIS methods (geophysical investigations in boreholes) and GTI (mud logging) in distinguishing low-power numerous collectors HC (hydrocarbons) in deep exploratory wells, complicated by the high caverns and drilled for saline drilling fluid. Limitations of techniques emisions and determine their characteristics leads to skipping of productive intervals and their erroneous selection. Data electrical methods (BKZ (lateral sounding), MKZ (microcerotermes sensing), IR (induction logging), PS (logging potentials spontaneous polarization)) in terms of the mineralized mud and cavernous wellbore distorted, poorly reflect the incision and therefore uninformative. There are no direct characteristics collector – positive increment on the microprobes (MHS (micro-gradient probe), MPZ (micro-potential probe) and clay crust against the collector by DS (inspection), at the substation are not marked minimum values of the net (Neglinnaya) terrigenous formations. Saturated and reservoirs on IR also not differentiated. Readings radioactive methods (COG (neutron gamma logging) and GGC-p (gamma-gamma density logs)) are distorted by the presence of large cavities in the wellbore. For successful execution of exploration drilling designed research methodology perspective on HC intervals. The method is based on an integrated use of all possible methods of GIS, the GTI and direct methods for the steady reservoir and determine their characteristics. Proposed rational complex GIS detailed geophysical studies in Sandstone reservoirs, exploration and appraisal wells drilled in saline solutions.
ABOUT THE INFLUENCE OF GEOLOGICAL HETEROGENEITY OF MOUTH BAR ON THE HYDRODYNAMICS OF THE RESERVOIR ROCK OF RED FOREST FIELD (CHINA)
The article considers the geological structure of C6 productive bed of Red forest oilfield (China). It is determined that reservoir rock belongs to mouth bar of delta front. The survey shows the laminated structure of the reservoir, consisting of several regressive sedimentation cyclical beds separated by impermeable clay layers. In the structure of the regression mouth bar are dedicated two subfacies: crest and slope. It is established that crest subfacie is characterized by high grain maturity and made more powerful and homogeneous sandy sediments with high permeability properties. Slope subfacie of mouth bar has a high stratification with frequent interlayering of discontinuous thin sand bodies composed of immature sediments with the deterioration of reservoir properties.
The presence of macroheterogeneity in bar sediments determines the filtration reservoir structure and its dynamics that must be considered when selecting the system of the injection wells location, the design of horizontal wells and design of hydraulic fracturing. It is shown that the most significant effect on the fluid dynamics of the reservoir have a layered structure of the reservoir, the location of injection and production wells in relation to the bar body and, especially, differences in the azimuthal direction of seepage flow and the strike of mouth bar sand bodies. The simulation results showed that the reservoir with a large number of layers is watered with more effectively, and the amount of remaining oil in it more than in the reservoir with a small number of layers; quick the water-cut and the decline in oil production are established in models where the sand body strike coincides with the direction of fluid flow. Recommendations on the organization of the flooding system for optimal oil extraction of laminated heterogeneous bar reservoir.
Variations of the geomagnetic field of the Earth have a strong negative impact on the modern technological system. In the development process of the North and the creation of large technological systems, it was found that part of the emergency definitely associated with the development of magnetic disturbances. The task of identifying and registering the operational parameters of the unperturbed geomagnetic field in a minimum of hardware and computing resources is quite acute.
The known in geophysical practice approaches to determine the reliability of operational parameters of the geomagnetic pole in the field have a number of obvious and significant drawbacks: rigid adherence to a given step sampling grid; low degree of automation of the process of determining the parameters of the geomagnetic pole; necessity for oversized and expensive equipment; a small number of the determined parameters.
In this paper method of determination and registration the parameters of the undisturbed geomagnetic field in the minimum hardware and computational tools and systems, and limited information and energy sources is proposed. The methods of implementing the mentioned method for operative and reliable geomagnetic dipole parameters automatic calculation is described. The realization of implementing the proposed mathematical and methodological bases on Android-based operation system using the languages of programming Delphi and Java is represented
Its practical application on a portable device with Android OS shows that the process of calculating the parameters of the geomagnetic field at the current position of the researcher is 100% automatic and the likelihood of methodological errors are minimized.