Methods and apparatus for investigating an earth formation and compensating for borehole environmental effects

Patent · Tue Jun 18 00:00:00 EDT 1985

OSTI ID:6416106

Scott, H D

In the illustrative embodiment of the invention disclosed, a neutron porosity logging tool adapted to log a mud-filled borehole includes one or more pairs of epi-thermal and/or thermal neutron detectors. The detector count rates are corrected to the effective count rates for fresh water in the borehole by applying thereto empirically-derived correction terms that are functionally related to the hydrogen index of the mud and, in the case of thermal detectors, also to the thermal neutron absorption properties in the mud.

• Assignee: Schlumberger Technology Corporation
• Patent Number(s): US 4524274
• OSTI ID: 6416106
• Resource Relation: Patent File Date: Filed date 5 Aug 1982; Other Information: PAT-APPL-405391
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
NEUTRON LOGGING
WELL LOGGING EQUIPMENT
NEUTRON DETECTORS
COUNTING RATES
FRESH WATER
HYDROGEN
NEUTRON DETECTION
RESERVOIR FLUIDS
THERMODYNAMIC PROPERTIES
DETECTION
ELEMENTS
EQUIPMENT
FLUIDS
HYDROGEN COMPOUNDS
MEASURING INSTRUMENTS
NONMETALS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RADIATION DETECTION
RADIATION DETECTORS
RADIOACTIVITY LOGGING
WATER
WELL LOGGING
020200* - Petroleum- Reserves
Geology
& Exploration
030200 - Natural Gas- Reserves
Geology
& Exploration