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Deep hydraulic fracturing stress measurements in the KTB (Germany) and Cajon Pass (USA) Scientific Drilling Projects: A summary

J. Baumgartner·J. H. Healy·F. H. Rummel·Mark D. Zoback
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Abstract

The determination of in situ stresses along deep vertical profiles was declared a key issue for two scientific deep drilling projects: the German Continental Deep Drilling Project (KTB) situated in northeast Bavaria in an area of complex variscian thrust tectonics and the CAJON PASS Project, located only about 4 km from the San Andreas Fault Zone In southern California. In the KTB project 7 successful hydrofrac stress measurements could be completed in a 4 km deep pilot hole between 0.8 to 3.0 km. At the Cajon Pass site a series of 23 hydrofrac stress measurements was performed in 2 wells between 0.9 to 3.5 km.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 34.19144816225324° to 50.217556505777594° latitude; -117.59418589093974° to 12.705253798878886° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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J. Baumgartner, J. H. Healy, F. H. Rummel, Mark D. Zoback. 1993. Deep hydraulic fracturing stress measurements in the KTB (Germany) and Cajon Pass (USA) Scientific Drilling Projects: A summary. https://pubs.usgs.gov/publication/70242904

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