Description [caption id="attachment_849" align="alignright" width="256"] Figure 1. Schematic of the GLT tool[/caption] Geochemical Logging Tool (GLT) used three separate modes of gamma-ray spectroscopy to obtain measurements of most of the major oxides that make up sedimentary and igneous rocks. Initial measurements provided estimates of Si, Al, Fe, Ca, K, U and...
Description The Dual Laterolog (DLL) provided two resistivity measurements with different depths of investigation into the formation: deep (LLd) and shallow (LLs). In both devices, a current beam 2 ft-thick (A0) was forced horizontally into the formation by using focusing (also called bucking) currents (A1- A2,...
Description The Enhanced Digital Telemetry Cartridge (EDTC-B*) is a downhole tool that combines two commonly run sensors with a high-speed telemetry downhole modem that can be used in high-pressure and high-temperature environments. The primary function is to provide high-speed (over 1 Mbps) communications between the wireline...
Description The GPIT* General-Purpose Inclinometry Tool provides inclinometer measurements. Tool orientation is defined by three parameters: tool deviation, tool azimuth, and relative bearing. The GPIT tool uses both a three-axis inclinometer and a three-axis magnetometer to make measurements for determining these parameters. The basic principle of downhole...
Description The Dipole Sonic Imager Tool (DSI-2) combines high-speed telemetry with simultaneous, 12-bit dynamic range digitization of an eight-receiver array. The sonde incorporates both monopole and crossed-dipole transmitters with an eight-station array of electronically configurable hydrophones for monopole and dipole reception. Combining new dipole-based technology with...
Description The LWD-CDR was an electromagnetic propagation and spectral gamma ray tool built into a drill collar. It had many similarities to dual induction tools: it responded to conductivity rather than to resistivity, operated in water- or oil-base muds, and provided two depths of investigation. It had better vertical resolution,...
Description [caption id="attachment_473" align="alignright" width="180"] Sixteen-electrode arrangement for the four-pad tool.[/caption] The Formation MicroScanner sonde (FMS) consists of four orthogonal imaging pads each containing 16 microelectrodes which are in direct contact with the borehole wall during the recording. The button current intensity is sampled every 0.1 in...
Description The Array Seismic Imager (ASI) consisted of an array of five seismic shuttles linked by a bridle to a signal-conditioning cartridge. Each shuttle sensor package contained three mutually orthogonal geophones fixed relative to the sensor package geometry. One geophone lay along the axis of the package (z-axis); the other...
Description The APS sonde is the key module in the Integrated Porosity Lithology system components. The electronic neutron source (minitron) allows epithermal neutron measurements and detector shielding, resulting in porosity values that are less influenced by environmental conditions. The near-array ratio epithermal porosity is the primary...
Description The Borehole Geometry Tool Kit (Schlumberger Seismos Prakla VSP Tool) was a three-component VSP tool that was used for many years in the petroleum exploration industry. At the time of its deployment in ODP, it was the slimmest available Schlumberger 3-axis VSP tool. Each of the...