Drilling and completion of the Urach III HDR test well

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:7369368

Meier, U; Ernst, P L

The hot dry rock (HDR) test well, Urach III, was drilled and completed in 1979. The borehole is located in Southwest Germany in the geothermal anomaly of Urach. The purpose of project Urach was to study drilling and completion problems of HDR wells and to provide a test site for a HDR research program. The Urach III borehole was drilled to a total depth of 3334 metres (10,939 feet), penetrating 1700 metres (5578 feet) into the granitic basement. Extensive coring was required to provide samples for geophysical and geochemical studies. Positive displacement downhole motors were used for coring and normal drilling operations. It was found that these motors in combination with the proper bits gave better results than conventional rotary drilling. Loss of circulation was encountered not only in sedimentary rocks but also in the granite. After drilling and completion of the borehole, a number of hydraulic fracturing experiments were performed in the open hole as well as in the cased section of Urach III. A circulation loop was established by using the single-borehole concept. It is not yet clear whether new fractures have actually been generated or preexisting joints and fissures have been reactivated. Evaluation of the results of this first step is almost completed and the planning of Phase II of the Urach project is under way.

• Research Organization: Preussag AG, Hannover, Germany
• OSTI ID: 7369368
• Report Number(s): SAND-81-0036C; CONF-810105-
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150303* -- Geothermal Exploration & Exploration Technology-- Exploratory Drilling & Well Logging
150901 -- Geothermal Engineering-- Drilling Technology & Well Hardware
COMMINUTION
DEPTH
DEPTH 3-6 KM
DIMENSIONS
DRILL BITS
DRILL CORES
DRILLING
DRILLING EQUIPMENT
ENERGY SYSTEMS
EQUIPMENT
EUROPE
FEDERAL REPUBLIC OF GERMANY
FRACTURING
GEOTHERMAL SYSTEMS
GEOTHERMAL WELLS
GRANITES
Geothermal Legacy
HOT-DRY-ROCK SYSTEMS
HYDRAULIC FRACTURING
IGNEOUS ROCKS
PERFORMANCE
PLANNING
PLUTONIC ROCKS
ROCKS
SPECIFICATIONS
WELL COMPLETION
WELL DRILLING
WELLS
WESTERN EUROPE