Our seismic data are a kind of digital palimpsest: a manuscript written on imperfectly erased reused paper that contains multiple overlapping layers of writing. Each layer of writing has its own story; it may be fresh and distinct, easy to read, or broken up into fragments and faded into near invisibility. In our processing we typically pay the most attention to the data layer that we plan to use for imaging, and ignore the others to the extent that we can get away with doing so. The deeper layers become “noise”. However, the better we can understand the various layers of the data, the better we can turn each layer into either additional useful signal or structured (i.e. predictable) noise. Preserving the structure of the noise is important. It allows us to do better, possibly much better, than we could by treating it as Gaussian random noise. For random noise the best we can typically do is stacking. While stacking is a powerful tool, its noise-suppression abilities are effective only up to a point. Each incremental increase in the stack size N costs the same to acquire, yet results in ever less S/N improvement. Even worse, noise in real data often contains statistical outliers that will dominate over the noise-suppression power of stack as N becomes large. We can damage our data at every step of the process from acquisition to final delivered product. If you are not checking for problems, you may be unaware that anything is amiss. The next game-changing improvement in our ability to guide business decisions by producing higher-quality Earth images may only happen if we can treat our seismic data with greater scientific rigor than has been standard practice. The goal of this book is to teach you the skills that you will need to do that.

Abstract The Bogdo–Baskunchak Nature Reserve is a geoheritage site in the Caspian Depression, near the Lower Volga River. The Salt Lake Baskunchak and the Mount Big Bogdo with the gypsum field are the main objects of interest. Local legends about this place and the history of salt mining and trading, as well as geological exploration, make this geoheritage site special. This natural landscape is intact, as seen by the first scientific expeditions of the eighteenth century organized by the Imperial Academy of Sciences and Arts in St Petersburg. Reports and papers about this area are associated with Pallas, Humboldt, Murchison, Eichwald, Auerbach, Pravoslavlev, Efremov and other scientists and expeditions. Extensive research and important discoveries were made in this area, mostly in mineralogy, stratigraphy, palaeontology, sedimentology, salt tectonics, and mining. This area reflects its long history of exploration and could be a good example of organizing the protection of geological landmarks and monuments in arid regions. In 1916, a Russian law was passed giving the government rights to organize reserves (zapovednik) for scientific and cultural purposes in the most remarkable natural areas. Only in recent decades have geological monuments in Russia become specially protected sites.

Abstract Three-dimensional circumferential CT-scans have transformed how core is described and calibrated with borehole image (BHI) datasets to refine reservoir rock typing and facies description. This paper focuses on the value of circumferential CT-scans in the assessment of plug and bed-scale heterogeneities. It shows how careful re-orientation and calibration with borehole images can help unravel sandbody geometries and orientation, and the potential effects of cross-cutting deformation bands on permeability architecture and sweep efficiency. This is demonstrated using aeolian-dominated core examples, supported with circumferential CT-scans, minipermeability data, conventional logs and BHI data, taken from the Jurassic Norphlet Formation from producing fields in the Gulf of Mexico. The formation overlies Early Jurassic Louann Salt, and syn-depositional halokinesis significantly influenced depositional accommodation space, facies distribution, and preservation potential. Furthermore, deposition during active salt tectonics has resulted in complex deformation band networks within these clean sandstones. CT-scan density contrasts highlight stratification types and deformation bands not always visible on slabbed core. Furthermore, BHI re-orientated CT-scans provide high-resolution dip/azimuth data and aid aeolian bedset bounding surface definition, which is important for determining dune geometry and stacking patterns. Hence, an integrated approach using core, circumferential CT-scan and calibrated BHI has been essential for deciphering the complexity of these deposits.