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The results of this study were obtained from an area in the North German Basin (NGB) located east of Bremen, Germany, where gas is produced from a deep Rotliegend sandstone reservoir. Faults and fractures play a major role in gas productivity. The deformations could have a negative influence on the productivity of the gas field as fractures are cemented and tight and may act as permeability barriers.

The main challenge of the joint project PROTECT is to unravel the specific potential of communicating systems that occur between reservoir and surface in the framework of CO2 injection, in order to assure long-term storage integrity and sensitive monitori

With the CRS method the incoherent seismic energy (noise) can be strongly suppressed. The increased stacking/gather fold, and additional wavefield attributes used in the time and depth domain processing enhance the imaging quality in both domains. The CRS time domain processing provides the requisites for an enhanced prestack depth migration with high potential, especially for data with low acquisition fold or high noise levels, where the velocity model is not too complex. The additional wavefield attributes can be used to enhance the velocity model in a robust noise-insensitive procedure, and to design migration operators. The field data examples of the CRS-PreSTM and CRS-PreSDM work flow reveal the high potential of noise reduction for seismic time and depth domain imaging. The key for the improved quality is the combined usage of the CRS attributes for the time domain S/N enhanced processing and regularization, the enhanced velocity building especially for noise contaminated data, and the migration parametrization in combination.

The success of ultradeep drilling projects, as e.g. within the German Continental Deep Drilling Programme (Kontinentales Tiefbohrprogramm, KTB) in the Oberpfalz strongly depends on the thermal and geological-tectonic environment of the well. In the present paper we apply the correlation of elevated temperatures and seismic reflectivity of the lower continental crust to the deep seismic network of the Oberpfalz. The results together with the correlation to other geoscientific data indicate increased temperatures in the area of the KTB location. These temperatures are most probably related to influences of the Eger graben and possibly are not yet measured at the surface using heat flow determinations.

The Common-Reflection-Surface (CRS) stacking technique provides a powerful time domain imaging especially in case of complex geology data with low signal-to-noise ratio. The macro-model approach does on principle save the effort to produce a macro-model. However, the method allows as well the input of a velocity model as a guide function, which is automatically improved. A coarse initial velocity model is helpful especially in case of strong multiple wavefields.

The reservoir of interest is located in the North German Basin at a depth of about 4000m. The Upper Carboniferous fluvial sandstone has been tested by 14 wells which are mostly covered by 3D seismic data.

The statistical treatment of deep seismic reflections from several different geological units has resulted in different reflectivity histograms. Reflectivity in old and cold shields differs significantly from that in younger, warmer areas. In the shields reflectivity is generally poor and concentrated in the upper crust whilst Caledonian and Variscan areas show strong reflecting lamellae in their lower crust. Also the length of the reflecting elements varies with age and heat flow. The lower crust in young areas is a zone of a strong viscosity minimum as derived from model studies with a temperature dependent rheology. The subhorizontal reflecting lamellae in the lower crust are considered to have been created in a large-scale high-temperature, low-viscosity ordering process whose remnants are still preserved today. Local-scale differences of reflectivity histograms define certain subprovinces which can be distinguished by their specific patterns.

The Upper Cretaceous Ilhabela sandstones, which represent the main reservoir unit in the Santos Basin, were deposited in a fluvial to shallow marine environment during a period of active basaltic volcanism. The volcanics have been partly eroded, providing the reservoir with volcanic rock fragments and causing a complex diagenetic history. This has resulted in the local occurrence of sandstones with complex lithology and elastic properties differing from the basin trend (Klarner et al, 2005). For better prediction and interpretation of the amplitudes and AVO behaviour of the Ilhabela reservoir it is essential to map the occurrence of the volcanics as well as the transport direction of their erosional products. In this paper, typical seismic features are presented which may help to identify volcanics in the Upper Cretaceous sequence.

In this study we focus on the development of a workflow, combining 3D retro-deformation with detailed seismic interpretation and well data, to investigate the distribution and magnitude of strain over a wide range of scales. We investigated a 3D seismic data set and constructed a 3D structural model to quantitatively assess geometrical parameters such as fault displacement and kinematic vectors. 3D retro-deformation of the structural model was used to validate its geometric and kinematic characteristics. Additionally, using coherency data we interpreted the fault pattern of one horizon in detail, in order to analyse fault parameters like length, density, and connectivity. Furthermore, we compare these results with natural data, such as fracture data from boreholes. The results of 3D retro-deformation verified the results of the detailed seismic interpretation and the well data, in terms of distribution and orientation of fractures. Therefore, we propose that 3D retro-deformation is a helpful tool to improve the prediction of fractures.