Oil and Gas Exploration

Methods and Application

Said Gaci, Olga Hachay, Said Gaci, Olga Hachay

• Publisher: American Geophysical Union
• Year: 2017
• ISBN:
  9781119227465
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Geology & Earth Sciences

Oil and Gas Exploration: Methods and Application presents a summary of new results related to oil and gas prospecting that are useful for theoreticians and practical professionals. The study of oil and gas complexes and intrusions occurring in sedimentary basins is crucial for identifying the location of oil and gas fields and for making accurate predictions on oil findings.

Volume highlights include:

• Advanced geophysical techniques for achieving hydrocarbon exploration efficiency from beneath the Earth
• Discussion of theoretical and practical approaches in solving problems related to exploring and mining new oil and gas deposits
• New geological concepts for predicting potential hydrocarbon targets
• Novel methods of control of the outworking of these deposits using different geophysical methods, significant for optimization of mining hydrocarbon and carbonate deposits
• Estimation of the degree of outworking of oil and gas deposits, to facilitate the use of space - time monitoring of different kinds of fields
• Analysis of exploration data by an efficient processing system, based on strong methods proven mathematically

Oil and Gas Exploration is a valuable resource for exploration geophysicists, petroleum engineers, geoengineers, petrologists, mining engineers, and economic geologists, who will gain insights into exploring new methods involved in finding natural resources from our Earth. Read an interview with the editors to find out more:
https://eos.org/editors-vox/where-and-how-can-we-find-new-sources-of-oil-and-gas

1
EXPERIENCE OF REGIONAL PREDICTION OF HYDROCARBON DEPOSITS PROSPECTING IN THE VICINITY OF URAL OIL AND GAS PROVINCES

Vladimir S. Druzhinin, Vjacheslav Osipov, and Nikolay Nachapkin

Institute of Geophysics Ural Branch of Russian Academy of Sciences (UB RAS), Ekaterinburg, Russia

Abstract

This chapter is devoted to investigating oil and gas content in the Ural region according to the position of the Earth’s crust deep structure. A significant volume of deep seismic soundings was provided in the Ural region by the Bagenov geophysical expedition, by the Institute of Geophysics (Ural Branch of Russian Academy of sciences), and by the Center of Regional Geophysical Research (GEON) during some decades. We have elaborated a new technology of seismic geomapping, based on new model conceptions about the structure of the upper part of lithosphere. We supplement the base of seismic research by the geological data (information about the oil and gas content of the region), the data of super deep boreholes, and area gravimetric data. That allowed us to construct a geological‐geophysical fault‐block volume model of the lithosphere (up to 80 km), to provide the tectonic mapping according to these cuts: the surface of ancient crystalloid crust and the main seismic geological surface M. On the basis of the obtained information compared with the data of hydrocarbon deposits location, new depth criteria of forecasting deposits in new regions and objects have been developed. We can assign some examples of positive forecasting. They are the Kueda region (south of Perm region) and the region of the town Khanti‐Mansyisk.

1.1. Introduction

In the last decade, interest in the information of Earth’s crust and upper mantle structure has steadily grown. That knowledge has become required for developing deep submerged sediments, which are the main source for refueling the world base of oil and gas of the 21st century, and for prospecting objects in new areas. Success of prospecting new fields of hydrocarbon (HC) deposits inside the territory of oil and gas areas of the Ural region is too low. One of the main reasons for this may be that the peculiarities of the deep structure chosen for detailed exploration are not usually taken into account. That situation is caused by the lack of sufficiently reliable data on the structure of the Earth's crust, as well as absence of criteria for the prediction of prospective areas. A simplified system of observation in deep seismic sounding oriented on the subhorizontal environment is in conflict with the complex block model of Earth's crust, established by using the dense continuous profiling systems and the results of deep drilling. First of all, we need to have information about the tectonic model of the upper lithosphere and also about the connection between the structural and tectonic elements of the sedimentary cover, including tectonics of crystalline crust and of deep fluid dynamic zones. That will determine the types of the Earth's crust as a generation source of hydrocarbons that contributes to their vertical migration into upper layers of the geological environment. The development of depth criteria that determine the formation of large hydrocarbon deposits was introduced in the 1960s. In the beginning it was realized in profile models, and then in area systems for constructing a geological‐geophysical volume model of the Ural's upper lithosphere and scheme of tectonic districts of the crystal crust. Conclusions about the prospects (or nonprospects) of areas were confirmed by subsequent detailed prospecting operations. The need for such an approach at the stage of regional and regional‐zonal forecast in this chapter is considered an example of research on oil and gas provinces of the Ural region.

1.1.1. Some Information About Oil‐Gas‐Reserves of Ural’s Region and Their Geological Environment

Overviews have been published in the works by Bochkarev and Brechuntsov [2008], Gogonenko et al. [2007], Dontsov and Lukin [2006], Megerja [2009], and Timonin [1998]. On the Ural region territory (48°–70° east latitude, 56°–68° north longitude), there are three large oil gas provinces (OGP). The most important one, by volume of developing hydrocarbon minerals, is western Siberia, followed by the Timan‐Pechora and Volga‐Ural OGPs. The main productive horizons in the western Siberian OGP are located in the Mesozoic interval at the depth 1.2–3.5 km, which is well studied by geologic and geophysical methods, and therefore discovery in the limit of known oil gas regions of large and super large HC deposits is unlikely. In the opinion of leading scientist‐oilers, a high capacity can define some negative structures of the near Ural part of the western Siberian plain—for instance, the Ljapinsky depression. As a whole, the resupply of the resource base of HC in the western Siberian OGP consists of the deeper horizons, first from the sub platform sediments of the Triassic‐Devonian age and in the disintegrated part of the basement (before Jurassic base). The research in that direction began in the mid‐1980s, but unfortunately there were not any significant results, only some objects corresponding to small oil deposits. Timan‐Pechora OGP differs by a widely known age interval of oil gas content of sedimentary rocks (from Silurian to Triassic, inclusive) and by a significant role of faults in the HC deposits location. That province is very well studied, except the eastern and southern regions. Namely, these territories are regarded as prospective for HC deposits prospecting. Regional‐zone searches for HC, which have been conducted in these regions, haven’t given any results yet. An actual problem of searching for HC in deeper areas of known productive horizons is encountered in the whole Volga‐Ural OGP, including for Perm and Bashkiria OGP, and on the eastern part of that region into the inner part of near Ural depression and in the western side of the Ural fold system.

The main cause of noneffectiveness of prospecting in the shown direction according to our opinion is that orientation in these works on the sedimentary‐migration theory of HC generation and deposits formation, using that as a base of the existence of oil deposits. An example is the deposit located in the pre‐Jurassic basement of western Siberia. It occurs due to horizontal migration of HC from the productive horizons of sedimentary basins. The next causes are related to ignoring the specificity of the deep structure and mainly vertical migration, which are the basic elements of developing a new paradigm of oil geology [Dmitrievskiy, 2009; Timurziev, 2010; Dmitrievskiy, 2012; Bembel and Megerya, 2006]. At last we see the imperfection of searching works technology, which does not take into account the complicated medium structure and nontraditional character of HC accumulation location.

1.2. Method of Information Analysis for the Regional Prediction

During 2006–2011 in the Institute of Geophysics, the research work of developing a method and creating a volume geologic‐geophysical model of the upper part of the Ural region lithosphere had been provided for the territory with coordinates 54°–68° n. l. and 50°–71° e. l. The main initial data had been of the same type of seismic geological sections of deep seismic sounding (DSS) profiles (geotraverses), developed by using the provided technology of seismic mapping of Earth’s crust [Druzhinin et al., 2013b, 2014a] and gravitational field in Bouguer reduction. A scheme of profile locations combined with the field ∆g is shown in Figure 1.1.

Figure 1.1 Location map of deep seismic sounding (DSS) and method of exchanged waves (MEW) profiles, combined with a map of anomaly gravitational field ∆g.

Legend: 1 = administrative borders of RF regions; 2 = Rubin‐1; RB‐2 = Rubin‐2; UR‐ Ural MEW; KRT = Kraton. Profiles of Bagenov geophysical expedition with participation of the Institute of Geophysics UB RAS: SVR = Sverdlovsk; GR = Granit; TRT = Taratash; KRU = Krasnouralsk; HNM = Hanti‐Mansian; SSJA = Northern Sosva‐Jalutorovsk; KRL = Krasnoleninsk; VNK = Vernenildino‐Kazim; VZO = Vizaj‐Orsk. Profile of Spetsgeofizika: KV = Kupjansk‐Vorkuta. Profile of the Institute of Geology Komi Center UB RAS: SKV = Syktyvkar; 3 = Ural super deep borehole.

In the first step of that method, the seismic section was used for the sublatitude Sverdlovsk intersection of the Ural 1000‐km length, which was developed according to materials of continuous profiling and systems of hodographs of refracted (weak refracted) waves with a length up to 300 km, wide refractions with an interval of registration from 0–20 km to 150–200 km. On the Ural region, we acquired 15 seismic sections of the Earth’s crust with total amount more than 10,000 km. In Figure 1.2a, b we can see as examples sections for the region of the super deep borehole (sublatitude Krasnouralsk and meridional Vizhai‐Orsk).

Figure 1.2 Legend: 1–4 = section surfaces of seism geological floors, which were constructed according to a set of seismic data, including the schematic velocity section: 1‐II (SGE), or of the ancient crystalline basement, 2‐III (SGE), or protocore; 3 = transition mega complex at the bottom of the crust; 4 = the main seism geological section M; 5 = assumed zones of deep faults (a) and deep reflected elements, which ta...

Table of contents

• Cover
• Title Page
• Table of Contents
• CONTRIBUTOR LIST
• PREFACE
• ACKNOWLEDGMENTS
• 1 EXPERIENCE OF REGIONAL PREDICTION OF HYDROCARBON DEPOSITS PROSPECTING IN THE VICINITY OF URAL OIL AND GAS PROVINCES
• 2 WAVELET‐BASED MULTIFRACTAL ANALYSIS OF LANDSAT 8 IMAGES: APPLICATIONS TO MINERAL DEPOSITS AND SHALE GAS RESERVOIRS
• 3 SEISMIC SIGNAL DENOISING USING EMPIRICAL MODE DECOMPOSITION
• 4 A LITHOLOGICAL SEGMENTATION TECHNIQUE FROM WELL LOGS USING THE HILBERT‐HUANG TRANSFORM
• 5 SEISMIC UNIX AND GNU OCTAVE FOR VSP DATA PROCESSING AND INTERPRETATION
• 6 SEISMIC SPECTRAL DECOMPOSITION APPLICATIONS IN SEISMIC: A REVIEW AND APPLICATION
• 7 ELECTROMAGNETIC GEOPHYSICAL RESEARCH WITH CONTROLLED SOURCE
• 8 REFLECTION OF PROCESSES OF NONEQUILIBRIUM TWO‐PHASE FILTRATION IN OIL‐SATURATED HIERARCHIC MEDIUM BY DATA OF ACTIVE WAVE GEOPHYSICAL MONITORING
• 9 DEFINING THE SURFACE OF THE FLUID‐SATURATED POROUS INCLUSION IN THE HIERARCHIC LAYERED‐BLOCK MEDIUM ACCORDING TO ELECTROMAGNETIC MONITORING DATA
• 10 HARDWARE AND SOFTWARE SYSTEM FOR RESEARCH IN OIL AND GAS BOREHOLES
• 11 APPLICATION OF BOREHOLE MAGNETOMETRY TO STUDY OIL AND GAS DEPOSITS IN WESTERN SIBERIA
• 12 A NOVEL MODEL TO ESTIMATE S‐WAVE VELOCITY INTEGRATING HÖLDERIAN REGULARITY, EMPIRICAL MODE DECOMPOSITION, AND MULTILAYER PERCEPTRON NEURAL NETWORKS
• 13 GEOPHYSICAL METHOD OF DEFINING RESIDUAL AND ACTIVE ROCK STRESSES
• 14 ON THE POSSIBILITY OF USING MOBILE AND DIRECT‐PROSPECTING GEOPHYSICAL TECHNOLOGIES TO ASSESS THE PROSPECTS OF OIL‐GAS CONTENT IN DEEP HORIZONS
• 15 ANOMALIES OF LOW DENSITY IN THE CRYSTALLINE CRUST OF THERMOBARIC ORIGIN: A NEW INSIGHT INTO MIGRATION AND LOCALIZATION OF HYDROCARBONS: CAVEATS AND PITFALLS
• 16 THE USE OF AEROMAGNETICS AND MICROMAGNETICS TO IDENTIFY POTENTIAL AREAS OF HYDROCARBONS IN THE MIDCONTINENTAL UNITED STATES
• Index
• End User License Agreement