Site:      Lamont-Doherty Earth Observatory, Palisades, NY

Well: Lamont Test Well 2 (TW-2)

Total depth: 753 ft (229 m)

Casing depth: 21 ft (6.4 m)

Nominal hole diameter (bit size): 7 in.

Logging Date: 1987 (Schlumberger) - 2000 (USGS)

Logging Company: Schlumberger/USGS

Sampling interval: 0.03 m (0.1 ft) - USGS Tools

Sampling interval: 0.1524 m (0.5 ft) - Schlumberger Tools

 

General Information

In 1980 the well TW2 was drilled to a depth of 229 m (753 ft), The well penetrates into the Palisades dolerite sill to 612 ft (186.5 m) and the Newark Basin sediments below. In July 1987 a set of geophysical measurements were carried out by Schlumberger including resistivity, density, porosity, natural gamma ray and formation geochemistry. In 2000 the USGS acquired caliper, natural gamma ray, resistivity, temperature and optical and acoustic borehole televiewer data.

USGS Tools/Measurements

1. Three-Arm Caliper (9074 Series), Century Geophysical Corp. / Well diameter; caliper run separately, measurements acquired logging up

2. Multifunction tool (9041 Series), Century Geophysical Corp. / Ambient temperature, natural gamma ray, short normal resistivity (16N), long normal resistivity (64N), lateral resistivity (64N/16N), fluid (mud) resistivity; all measurements were acquired logging down

3. Optical and Acoustic Borehole Televiewer.

The USGS data is available in LAS format. The depth in the LAS files is given in feet.

Only the optical BHTV is available online in WellCAD format.

A Null value of -99999.0 may replace invalid log values.

Schlumberger Tools/ Measurements

Tool stri	Run	Top depth (m)	Bottom depth (m)	Notes
1. DLL/GR	Main	55	223
	Repeat	169	224
2. LDT/CNTG/NGT	Main	27	229
	Repeat 1	0	109
	Repeat 2	205	229
3. ACT/GST/NGT	Upper	0	127
	Lower 1	75	225
	Lower 2	75	227
	Repeat	224	227

• DLL/GR - Array Induction Imager/Accelerator Porosity Sonde/ Spontaneous Potential/Enhanced Digital Telemetry Cartridge
• LDT/CNTG/NGT - Multi Mode Array Sonic Service Tool/General Purpose Inclinometry Tool/Enhanced Digital Telemetry Cartridge
• ACT/GST/NGT - Combinable Magnetic Resonance/Enhanced Digital Telemetry Cartridge

All Schlumberger data have been converted into ASCII and are included in the online database.
The depth in the ASCII files is given in meters.
A Null value of -999.25 may replace invalid log values.

For any question about the data or about the LogDB database, please contact LogDB support: logdb@ldeo.columbia.edu.