Effective Stress (σ’) “Effective Stress” (σ’) is a geotechnical engineering term. Effective Stress is a function of “total stress,” and is due to the solid particles of soil. Effective stress represents an excess of stress above pore-water pressure (or neutral stress). Effective Stress Formula Effective Stress = Total Stress – Pore-Water Pressure.

Lithosphere Lithosphere: The lithosphere comprises the Earth’s crust as well as part of the upper mantle. In fact, the lithosphere is approximately 100 kilometers thick and is relatively strong as compared to the underlying asthenosphere.

Potentiometric Surface The term “Potentiometric Surface” means the hydrogeological surface that represents the total hydraulic head of groundwater from a confined aquifer or semi-confined aquifer that’s under pressure. The Potentiometric Surface of an aquifer is defined by the level to which water will rise in a groundwater monitoring well (that’s exclusively screened within said aquifer).

Soil Compaction Testing or Soil Density Testing Soil compaction testing, or soil density testing, is the process by which the density property of a soil mass is increased in the field by various means, and monitored by a professional geologist in accordance with local building department specifications. During the placement of engineered backfill material, density…

Volcanology Volcanology: Volcanology is a branch of geology that focuses on the study of volcanos. In volcanology, geologists conduct field and laboratory investigations to learn about continental, coastal, and submarine volcanic activities. In fact, volcanology ties into many other branches of geology. For instance, a volcanologist may study the geochemistry of igneous rocks, such as…

Methane Alarm System Methane Alarm System: As per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a methane alarm system is part of an active methane mitigation plan. A methane alarm system is a group of interacting components and circuits that synchronize to monitor and annunciate the status of…