| In recent years, igneous rock, as a new reservoir of oil and gas exploration both at home and abroad has aroused widespread attention, showing the great potential for exploration and development of the reservoir rock. Therefore, the reservoir rock has become a new growth point for oil and gas reserves, petroleum geology caused widespread concern in academic circles, has become an important area in the oil and gas exploration. However, the reservoir rock has a high initial yield but decrease rapidly, widely distributed but smaller reservoir, lithofacies, lithology changes fast, the type of reservoir conditions and reservoir characteristics are complex, which are led to certain difficulties associated with igneous rock reservoirs exploration and development. Therefore, the comprehensive use of geological, geophysical means to combine the reservoir rock is very important in today's oil and gas exploration.This paper based on today's actual situation of igneous reservoir exploration and development, the main thesis of the work completed:1 .Comprehensive analysis of the characteristics of the physical properties of igneous rocks: The spatial distribution and physical properties of igneous reservoir is the basis theorety to identify reservoir rock by geophysical prospecting tools. To based on rock properties from the magnetic susceptibility, density, resistivity, log characteristicsof the rock, the possession of the petrophysical parameters for analysis, find out the changes in the law, as the interpretation basis of gravity and magnetic, electrical, earthquake data.2. Synthetic seismogram by reconstruction of acoustic curve to identify igneous rocks: In igneous rock areas, due to the distribution of igneous rock discontinuity, uncertainty and other factors as well as the volcanic eruption near the crater caused by the characteristics of clutter reflection, some igneous rock of different lithologic are difficult to distinguish between acoustic curves and some igneous rock intrude into other surrounding rock to make them alteration and make it more difficult to distinguish between acoustic curves, but as a result of igneous rocks are impackted in the process of diagenesis by other factors, which make the rocks characteristics in other well curve, easy distinction, so in the area of igneous rocks, the use of the log response curve associated with the lithology reconstitute acoustic curve with the same dimension, combined with the low-frequency acoustic logging information and other high-frequency information to reconstructe acoustic curve, make it to reflect the stratigraphic characteristics of speed and wave impedance, but also reflect differences in lithology, in order to establish better link between log information and seismic data. In the seismic data to achieve accurate calibration and to identify the purpose of reservoir rock.3. Seismic data analysis of complex wavelet spectrum: spectrum analysis is an interpretation based on the frequency of reservoir technology, which demonstrates to us is a new method of seismic interpretation. Through the discrete Fourier transform or complex wavelet transform seismic data from time domain to frequency domain, conversion amplitude spectrum has been calculated to explain the staff not only from the profile, but also from the plane to see the characteristics of thin-layer interference. In igneous rock areas, due to the unique rock petrophysical characteristics of the spectrum ,through the complex wavelet to analy the characteristics of its plane, combined with other attribute information, to provide effective foundation on identifying igneous rock in three-dimensional seismic data.4. Velocity inversion, the inversion of magnetic and seismic: The use of sequence stratigraphic interval velocity inversion of seismic lithology is an important means of inversion and methods. As long as between the different igneous rock lithology, igneous rock with the rock between the apparent velocity difference, it is possible to calculate the speed of analysis of igneous rock layer. Igneous rocks as of its unique high-magnetic, high-density characteristics reflect clearly in the non-shock characteristics of geophysical data, in accordance with the characteristics of igneous rocks in the combination of gravity and magnetic field characteristics with seismic profiles, joint inversion to determine the boundaries of rock-like characteristics and production.5. Igneous rock facies and reservoir performance analysis:Igneous rock lithofacies have close relationship with igneous reservoir. Based on core drilling, cutting and seismic, well logging, research the response characteristics of different lithofacies in well logs and seismic profiles, analy the reservoir performance of different lithofacies, which play an important role in reservoir prediction of rock.The work is to analy and process the logging, seismic and other geophysical data and applied research in Qikou depression, the main results achieved and conclusions are as follows:1. Summing up a set of tracking method of igneous rocks by gravity and magnetic data, three-dimensional seismic data and logging data.2. Apply a series of integrated geophysical methods to identify igneous rock, as curve reconstruction of synthetic seismogram, seismic data analysis of complex wavelet spectrum, velocity inversion, the inversion of magnetic and seismic and so on,and have achieved significant results.3. Analy the relationship of igneous rocks and igneous reservoir, the lithofacies of the outbreak and overflow are beneficial to the development of igneous reservoir.4. Research igneous accumulation mechanism and accumulation model of Qikou depression. Found that the main reservoir are the diabase and diabase - contact metamorphic belt reservoir. Pool-forming mechanism and its accumulation model can be divided into two types of cracks from the source - melting reservoir rock penetrated pass; from another source for the fractured intrusive rocks - metamorphic rock reservoir.The application of well and seismic data to identificate and predicte reservoir rock, it also recognized there are still some issues still need to be improved: (1) In the use of logging data to identify igneous rocks, should be logging as much as possible to collect other information such as image logging, etc.; comprehensive utilization of all kinds of logging information to improve the identification of igneous rocks accuracy. (2) In the three-dimensional seismic data to identify igneous rock, the aera of less and absence wells on the rock are not accurate, due to igneous development of complex regional tectonic rock, fracture more, so exist multiple solutions from known to the unknown by infereing. (3) In case of analysis of rock core drilling, the core should be more testing, analy porosity and permeability, and identification of igneous reservoir better.
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