Geography is one of the ancient earth science. The word ‘Geo’ meaning ‘Earth’ and ‘graphy’ meaning ‘to describe’ was first used by Eratosthenes, a Greek scholar in third century B.C. Geography is basically the study of the earth’s surface and associated changes and impacts associated with it. It is the study of the interactions of all physical and human phenomena and also the landforms created during these interactions. Physical geography is one of the main discipline of geographical science. It is mainly concerned with the study of the spatial patterns of weather and climate, soils and vegetation, water in all the forms, animals and all the landforms created as a result of all the external forces acting on them. Physical geography not only describes the history, creation or the structure of the landforms but also the factors responsible for creating them, the positive side as well as the adverse effects associated with them.
Oceanography, a vital branch in physical geography, is related to geology and seismology. Oceanography deals with the study of ocean, ocean floor and ocean waves. Geology is the study of rocks and minerals retained since the geological times while seismology refers to that branch of science which studies about the earthquakes and the earthquake waves. The drifting of ocean plates creates faults which gives rise to earthquakes and tsunamis. Californian bay area was struck by an earthquake recently this year which has been claimed to be one of the strongest earthquake in the last 25 years. It incurred major losses due to earthquakes. The magnitude of the earthquake was 6.0. California’s bay area is located near to the Pacific Ring of Fire which is known to be the main center of major active volcanic eruptions. Like all other earthquakes, this one too was born out of major fault in the ocean floor plates, creating mountains, giving rise to volcanic eruptions and triggering earthquakes. There was mainly this continental drift or sliding of ocean plates creating such disasters. Here comes the concept of implementing GIS and associated disaster management and mitigation process. The California Department of Conservation, Division of Mines and Geology(CDMG), has started the Seismic Hazard Mapping Program for detecting the hazard locations and plan for a better land-use planning. The movement of the sea floor crustal plates are constantly monitored with latest technologies. Geologists create digital geologic maps and track the earthquake waves. Earthquakes happen whenever there are faults along the fault lines in the ocean floors. Geospatial technology and tools are implemented for mapping vulnerable and threatened areas as well as changes in the ocean floor. Oceanography when implemented along with Geographical Information System gives a much clear and accurate results of such disasters. These disasters can be well managed through awareness, preparedness and mitigation programs.
The California Seismic Safety Commission. California Earthquake Loss Reduction Plan, 1997-2001