# Methodology and Results of Detailed 3D Seismic Exploration in the Zhezkazgan Ore District
## 1 Introduction  
As the most comprehensive and informative method for geophysical investigations, seismic exploration has long been considered an expensive method for ore deposit prospecting and exploration. However, the success of seismic exploration in relation to the prospecting and exploration of complex oil and gas deposits, as well as the challenges of studying deep and hidden ore deposits through the use of conventional geophysical methods, has radically changed the role of seismic exploration in the context of ore geophysical methods [1, 2, 3, 4, 5]. In a composite medium represented by intensively dislocated sequences of effusive-sedimentary and igneous rocks in folded zones, seismic exploration is mainly used for regional studies and mid-scale geological mapping. At the same time, seismic exploration has rarely been used to delineate promising ore-bearing areas and ore targets for exploration drilling [6, 7, 8, 9]. In the past, due to hardware and software limitations, the 2D single-fold reflection seismic method has traditionally been used to explore geological sections in ore mining areas. Seismic reflections have been shown to poorly delineate geological boundariesin the shallowest part of a section (down to 500-800 m depths). The spatial-genetic relationship between ore localization on the one hand and the rocks of a certain lithological composition, magmatic bodies, tectonic zones, etc., on the other has been established in numerous ore-bearing regions. Therefore, the seismic exploration method is most often used to study the structural tectonic composition of the folds and the morphology and prerequisites of the occurrence of ore-bearing intrusions. The study of the composition of ore-hoisting deposits is conducted to a depth established by the exploration assignments with a scale not exceeding 1:50,000 as a rule [10,11]. Since the modern seismic reflection method of Common Depth Point (CDP) for seismic exploration became widely used at mining sites, seismic exploration has proven to be effective at studying both the gently sloping boundaries of sedimentary and metamorphic sequences and the complex structures of effusive-sedimentary horizons, the morphology and internal composition of intrusions, and the mapping to significant depths of faults, thrusts, and large tectonic zones. Seismic exploration both clarifies the delineation of the intrusions and determines the position of their apical parts, as well as tracing the contact lateral surfaces and the lower edges. This improves the efficiency of prospecting for contact metasomatic, skarn, stockwork, and other deposits [12,13]. The capability to address more complicated and higher-level assignments such as verifications and 3D assessments of either direct ore control factors or ore deposits at practically developed depths has become possible with the introduction of 3D seismic exploration methods. High-resolution seismic reflection and 3D seismic modeling with identification of zones of elastic property alterations (amplitude, frequency, velocity characteristics, etc.) can locate deposits at depths of 3000 m and more [14,15]. To solve the abovementioned tasks, direct methods of prospecting (drilling) should be substituted with indirect methods based on composite geological modeling of ore targets which rely on the extensive use of state-of-the-art systems for seismic data processing and interpretation. At the same time, the cost of prospecting and exploration efforts will be drastically reduced [16, 17, 18]. To date, new and continuously improving techniques for seismic data processing and interpretation have been developed, bringing in new opportunities for the accumulation of useful events and for the achievement of effective noise attenuation in complex geological target investigations [19, 20, 21]. A wide range of analysis, interpretation, and well-logging methods are currently used for efficient oil and gas exploration.