RFG 2018 Conference

GeoWord of the Day

The GeoWord of the Day is a free service of the American Geosciences Institute. All of the terms and definitions are from the Glossary of Geology, 5th Edition Revised.

Subscribe via EMail to the GeoWord of the Day.

marsh creek . A drainage channel developed on a salt marsh.

marine ecology . The study of the relationships between marine organisms and their environment, including associated organisms.

discrete spectrum . In harmonic analysis of time series, a plot of power or variance at discrete frequencies or harmonics.

tyrrellite (tyr-rell'-ite). A metallic bronze cubic selenospinel mineral of the linnaeite group: (Cu,Co,Ni)3Se4 .

chaméanite (cha-mé-an'-ite). A metallic gray cubic mineral occurring in intergrowths with giraudite: (Cu,Fe)4As(Se,S)4 .

flame test . A qualitative analysis of a mineral made by intensely heating a sample in a flame and observing the flame's color, which will be indicative of the element involved, e.g. green from copper.

lateral accretion . Sediment accumulation at the side of a channel or bank. Lateral accretion deposits or sidebars grow towards the channel axis whereas cross bedding dips parallel to channel axis. Cf: vertical accretion.

exchangeable anions . Negatively charged ions held on or near the surface of a solid particle by a positive surface charge and which may be easily replaced by other negatively charged ions, e.g., with a Cl- salt.

driven well (driv'-en). A shallow well, usually of small diameter (3-10 cm), constructed by driving a series of connected lengths of pipe into unconsolidated material to a water-bearing stratum, without the aid of any drilling, boring, or jetting device. Syn: tube well.

fusulinid (fu-su-lin'-id). Any foraminifer belonging to the suborder Fusulinina, family Fusulinidae, characterized by a multichambered elongate calcareous microgranular test, commonly resembling the shape of a grain of wheat. Range, Middle Pennsylvanian to Upper Permian. Syn: fusuline. See also: alveolinid.


Subscribe to GeoWord of the Day