This is an abbreviation for a well log acquired after or during drilling. The code LLST is a unique identifier to recognize this particular log and can be found in any (ASCII) log files provided by the logging company. Value of LLS Which Would Have Been Read if Results Were Good is the offical name for this log. This log is not often acquired after (or during) drilling a well.

Use this log to investigate the resistivity, measured by a laterolog (or guard log) resistivity device, which represents a measurement made approximately one to two feet into the formation; generally considered to measure the formation where it contains fluids which are comprised primarily of mud filtrate.

This log usually has the unit 'Resistivity'. This is the property of a material which resists the flow of electrical current. The ratio of electric-field intensity to current density. The reciprocal of conductivity.

Data for this log is produced by a tool that uses a laterolog logging technique and can be used to investigate the resistivity of the formation. Similar logs are listed below:

• Micro-laterolog resistivity (RMLL)
• 12 Azimuthal Shallow Resistivities (HARS)
• HALS Uncorrected Laterolog Shallow Resistivity (HLSU)
• Deep resistivity (RD)
• HALS Uncorrected Laterolog Groningen Resistivity (HLGU)
• High Resolution Deep Resistivity (HRLD)
• Shallow resistivity (RS)
• Proximity resistivity (RPRX)
• Laterolog Shallow Resistivity (LLS)
• Derived Filtered Shallow Resistivity derived (RFLF)