The API Natural Gamma Ray solution is a probe-based, API calibrated sensor that detects naturally occurring gamma radiation from the formation.  It has been designed to be fully compatible with Scientific Drilling’s MWD systems and supports all BHA configurations.

DELIVERING THE ULTIMATE VALUE

• Supports all BHA sizes
• Works seamlessly real-time with both MP and EM MWD
• High Temperature Option Available – Rated at 350°F (177°C)

TARGET APPLICATIONS

• Shale/Non-Shale Determination
• Lithology Identification
• Offset log and Formation Correlation
• Casing and Coring Point Selection
• Shale volume Estimation
• Geosteering

MEASUREMENT SPECIFICATIONS

• Detector Type - NaI Scintillation Crystal 
• Gamma Range - 0 - 1,000 AAPI 
• Recording Rate - 1 data point every 5 seconds 

Source : https://scientificdrilling.com/technology-services/logging-while-drilling/sci-gamma/

Scientific Drilling International

Scientific Drilling International (SDI) is an independent directional drilling and wellbore navigation, surveying and logging service company serving customers worldwide.