About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract

AAPG Bulletin, V. 105, No. 10 (October 2021), P. 1947-1971.

Copyright ©2021. The American Association of Petroleum Geologists. All rights reserved.

DOI: 10.1306/03122120032

Origin, migration pathways, and prediction of high carbon dioxide accumulations in the Lower Saxony Basin (northwestern Germany): Part II

Johannes Schoenherr,1 Volker Lüders,2 Maike Leupold,3 Bianca C. Pauli,4 and Lars Reuning5

1ExxonMobil Production Deutschland GmbH (EMPG), Hannover, Germany; [email protected]
2German Research Centre for Geosciences (GFZ), Telegrafenberg, Potsdam, Germany; [email protected]
3Energy & Mineral Resources Group, RWTH Aachen University, Aachen, Germany; [email protected]
4Forschungszentrum Jülich GmbH, Jülich, Germany; [email protected]
5Institute of Geosciences, Christian-Albrechts University Kiel, Kiel, Germany; [email protected]

ABSTRACT

Predrill risk assessment for the presence of nonhydrocarbon gases in oil and methane reservoirs is challenging and perhaps commonly an underestimated task. Although the same assessment principles apply for source and migration scenarios, the interplay of both play elements in basin history is different because of diverse origins and oftentimes unusual occurrences of nonhydrocarbon gases. The southern upper Permian Zechstein-2-Carbonate (Ca2) fairway in northwestern Germany represents such a setting, where CO2 contents >60 vol. % have been encountered in an otherwise methane-dominated area. The CO2 is well constrained to be the product Previous HitfromNext Hit thermal decomposition of ultra–deeply buried Devonian carbonates (part I published in this issue). In this study (part II), CO2-rich tectonic veins sampled for part I have been directionally reoriented in drill cores, showing a dominant Previous HitnortheastNext Hit-southwest strike. Only very few faults can be identified in Previous HitseismicNext Hit Previous HitdataNext Hit, connecting the deep CO2 source through the approximately 3-km-thick Carboniferous section with the Ca2 reservoir. Fluid inclusion analyses of hydrothermal cements Previous HitfromNext Hit the Previous HitnortheastNext Hit-striking veins reveal up to 100 mol % CO2, formation temperatures up to 315°C, and near-lithostatic pressure conditions. The Previous HitnortheastNext Hit strike of the faults is parallel to the main contraction direction during Late Cretaceous basin Previous HitinversionNext Hit and therefore marks the most likely timing for CO2 migration. The high CO2 content wells are located within the hanging wall of seismically defined Previous HitnortheastNext Hit-striking faults, enabling lateral injection of CO2 into downthrown Ca2 fault blocks. This pattern enhances predictability of nonhydrocarbon gases for neighboring trap structures and in similar petroliferous basins.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Protected Document: $10
Internal PDF Document: $14
Open PDF Document: $24

AAPG Member?

Please login with your Member username and password.

Members of AAPG receive access to the full AAPG Bulletin Archives as part of their membership. For more information, contact the AAPG Membership Department at [email protected].