Caldera: A large, circular depression in a volcanic terrain, typically originating in collapse, explosion, or erosion.

CALCULUS: The branch of mathematics that deals with limits and the differentiation and integration of functions of one or more variables.

Carbonate ion: The anion group CO3 with a charge of minus two.

Carbonate platform: A submarine or intertidal shelf whose elevation is maintained by active shallow water carbonate deposition.

Carbonate rock: A rock composed of carbonate minerals, especially limestone and dolomite.

Cataclastic rock: A breccia of powdered rock formed by crushing and shearing during tectonic movements.

Cation: Any ion with a positive electric charge.

Central vent: The largest vent of a volcano, situated at the center of its cone.

Chemical engineering is the branch of engineering that deals with the application of physical science with mathematics, to the process of converting raw material or chemicals into more useful or valuable forms. In addition to producing useful materials, chemical engineering is also concerned with pioneering valuable new materials and techniques, an important form of research and development. A person employed in this field is called a chamical engineer

Chemical weathering: The total set of all chemical reactions that act on rock exposed to water and atmosphere and so change it minerals to stable forms.

CHEMISTRY:is the science concerned with the composition, structure, and properties of matter, as well as the changes it undergoes during chemical reactions.

Chert: A sedimetary form of amorphous or extremely fine-grained silica, partially hydrous, found in concretions and beds.

Cinder cone: A steep, conical hill built up about a volcanic vent and composed of coarse pyroclasts expelled from the vent by escaping gases.

Civil engineering:is the branch of engineering hat deals with the design, and construction of public and private works, such as infrastructure ( water supply,treatment etc.), bridges and buildings.

Clastic rock: A sedimentary rock formed from mineral particles (clasts) that were mechanically transported.

Clay: Any of a number of hydrous aluminosilicate minerals formed by weathering and hydration of other silicates; also, any mineral fragment smaller than 1/255 mm.

Coal: The metamorphic product of stratified plant remains. It contains more than 50 percent carbon compounds and burns readily.

Coastal plain: A low plain of little relief adjacent to the ocean and covered with gently dipping sediments.

Composite cone: The volcanic cone of a stratovolcano, composed of both cinders and lava flows.

computer is a machine that manipulates data according to a list of instructions.

Construction:The systematic act or process of building or erecting buildings, roads or other structures.

Contact metamorphism: Mineralogical and textural changes and deformation of rock resulting from the head and pressure of an igneous intrusion in the near vicinity.