Well Graded Soil Well Graded: In the soil classification process of geology, well graded soil represents a sedimentary soil sample that fully displays all of the possible grain sizes for that soil classification, in accordance with the Unified Soil Classification System (USCS). For example, a well graded sand (SW) comprises fine, medium, and coarse grains…

Extrusive Rocks Extrusive Rocks: In the volcanology branch of geology extrusive rocks are igneous rocks that have been erupted onto the Earth’s surface, before forming and crystallizing. On the other hand, intrusive rocks form and crystallize under the Earth’s ground surface. Extrusive rocks are typically microcrystalline and aphanitic, because of the faster rate of cooling…

Unobstructed Opening Definition in Methane Mitigation Unobstructed Opening: Per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, an unobstructed opening is a permanent clearance or gap in the walls, floors, or ceiling of a structure, to allow for direct fresh airflow. In methane mitigation plan applications, this does not…

Surface-Wave Magnitude “Surface-Wave Magnitude” is the magnitude of an earthquake that scientists estimate using measurements of the amplitude of surface waves.

Direct Shear Test A Direct Shear Test is a geotechnical engineering laboratory procedure that measures the shear strength value of a soil sample.

Intrusive Rocks In the volcanology branch of geology, intrusive rocks are igneous rocks that form and crystallize under the Earth’s ground surfaces, within other geologic formations. In fact, intrusive rocks form by the process of magma shooting through pre-existing sedimentary, igneous or metamorphic rocks. For instance, a pegmatite dyke or a batholith. On the other…