Limestone is a sedimentary rock composed largely of the mineral calcite (calcium carbonate: CaCO3). Limestones often contain variable amounts of silica in the form of chert or flint, as well as ... > more
Sequence stratigraphy is a relatively new branch of geology that attempts to link prehistoric sea-level changes to sedimentary deposits.
The 'sequence' part of the name refers to cyclic sedimentary ... > more
Earthquake liquefaction, often referred to simply as liquefaction, is the process by which saturated, unconsolidated soil or sand is converted into a suspension during an earthquake. The effect on ... > more
A gene is a locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with regulatory regions, transcribed regions and/or other functional sequence regions. ... > more
An earthquake is the result of a sudden release of stored energy in the Earth's crust that creates seismic waves. Earthquakes are accordingly measured with a seismometer, commonly known as a ... > more
This article is devoted to temperature changes in Earth's environment as determined from geologic evidence on multi-million to billion (109) year time scales. The last 3 million years have been ... > more
Global warming refers to the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation.
The global average air temperature ... > more
The horseshoe crab (Limulus polyphemus) is an arthropod that is more closely related to spiders than crabs. Horseshoe crabs possess the rare ability to regrow limbs lost. Limulus has been extensively ... > more
Mean sea level (MSL) is the average (mean) height of the sea, with reference to a suitable reference surface. Defining the reference level, however, involves complex measurement, and accurately ... > more