Core Barrel Temperature Tool (CB-TT)


cb_tt_fig1The Core Barrel Temperature Tool (CB-TT) was developed by the Borehole Research Group in order to assess temperature conditions while drilling and determine if conditions were favorable for subsequent wireline and Logging-While-Drilling operations in hydrothermal environments. Along with the Drill String Acceleration Tool CB-DSA-XM, the CB-TT enabled the acquisition of digital measurements while coring. The CB-TT’s measurements of borehole temperatures while drilling could then be correlated to pump rates used during coring operations in order to determine the feasibility of performing logging operations in the high temperature conditions associated with superheated water adjacent to hydrothermal vents. The CB-TT contained a thermocouple and a battery operated electronic board encased in a single dewar inside the pressure case that was designed for the CB-DSA.

The CB-TT was used on ODP Leg 193.



• Borehole temperature assessment while drilling
• Comparison of pumping rates to temperature
• Estimation of borehole temperature rebound while drilling

Log Presentation


Tool Specifications

Temperature rating: 248° F (120° C)
Pressure rating: 10 kpsi (6.9 kPa)
Diameter: 3.375 in (8.57 cm)
Length: 47 in (1.2 m)
Weight: 60 lbs (27.2 kg)
Memory: 4 Mb
Power source: lithium batteries
Battery life: about 12 hrs

Measurement Specifications

    Range: 0-599° F (0-315° C)
    Resolution: 1.8° F (1° C)
Pressure measurement range:
    Range: 0-10 kpsi (69 MPa)
    Resolution: 1 psi (6.9 K Pa)