Heave compensation and formation strength evaluation from downhole acceleration measurements while coring

LDEO Publication: 
Publication Type  Journal Article
Year of Publication  2002
Authors  Guerin, G.; Goldberg, D.
Journal Title  Geo-Marine Letters
Volume  22
Issue  3
Pages  133-141
Journal Date  Nov
ISBN Number  0276-0460
Accession Number  ISI:000179924200003
LDEO Publication Number  6455

In order to evaluate the efficiency of heave compensation in the Ocean Drilling Program, we developed a device measuring the acceleration of the core barrels. First results show that heave compensation limits bit motion to 10% of the surface heave. We also use the acceleration data to characterize the formation. On rotary corers, acceleration amplitudes decrease with increasing hardness of the formation. Comparison with geophysical logs shows that this relationship can resolve cm-scale features. On piston corers, the maximum acceleration is characteristic of the sediment shear strength. Easy and fast to deploy, this tool allows to characterize formations before any sample analysis.


627GATimes Cited:0Cited References Count:9

URL  <Go to ISI>://000179924200003
DOI  DOI 10.1007/s00367-002-0104-z