Coastal and Marine Geology PDF Print E-mail

Responsibilities

 

Coastal areas around the world are places of extreme importance for their richness in biodiversity and mineral resources. But these are also the places of high-density settlement and susceptible to natural hazards. Offshore parts are equally important to any country, as these areas are rich in marine fauna and mineral resources. A number of countries in the world are mining minerals from the shallow seafloors as well as oil & gas from offshore locations. Bangladesh being the second largest delta in the world does have enormous coastal offshore areas with bright prospects for exploiting mineral and other natural resources.

 

The combined flow of the Ganges-Brahmaputra-Meghna rivers in one hand has been flooding a vast tract of the coastal plain and eroding river banks enormously in every year during monsoon; on the other hand, more than a billion tons of sediments are being deposited per year due to the same flow and a major portion of the sediment reaches at the outer part of the Meghna estuary. Deposition of considerable parts of the sediment load, about 300 million tons per year has been forming new islands, shoals and lower tidal floodplains in the estuarine parts, and thus expanding the coastal land and also saving the coastal peninsulas of those parts from erosion.  But some other coastal parts such as Sunderbans, Cox’s Bazar, Teknaf etc., are facing severe erosion in recent years due to less availability of sediments which play a vital role in combating this natural hazard.

 

This branch is engaged to explore the environmental and ecological conditions of the vast coastal areas being controlled by various geological factors originated from actions and interactions between the land and sea. Moreover, this branch does have a vital role in delineating the delta building processes along with their history and also afford the valuable information about the economic zones of the coastal region with its prospect of mineral resources and various environmental aspects. 

 

This branch has got also some significant contributions to the Coastal Zone Management Program including investigation of various environmental related issues and improving the socio-economic conditions of the coastal dwellers. Along with its regular geological activities, the branch has its involvement with a vital project concerning the Maritime Boundary Delimitation of Bangladesh being conducted by the Ministry of Foreign Affairs.

 

To maintain the national development of Bangladesh, the Government undertakes a number of pragmatic programs to construct road communications, protect the river banks making embankment and river training, enhance the crop productions, build up new industries, supply drinkable water, manage the flood situation, and to defend the coastal people from various natural calamities by constructing dams and cyclone shelters. This branch also facilitates the aforesaid programs by providing various useful data and information. The proper use of these data will not only help to successful completion of the national programs but also secure the loss caused by diverse natural disasters.

 

 Activities

 

·          To find out the problems related with the coastal erosion, land subsidence, water logging and saline water intrusion in the coastal area, so that we can protect the environment of the coastal area specially the Mangrove Forest which is destroying very rapidly.

·          To locate the coastal hazardous areas using remote sensing techniques and GIS tools along with field investigations.

·          A huge proportion of the coastal land is currently being used for prawn culture and for production of salt which create many terrible impacts on the coastal environments. The appropriate use of the land is very essential to protect the environments and hence, the awareness among the coastal people has to be created.

·          There is a speculation among the international community that two-third of our coastal region may go under water by 2050 A.D. as a consequence of sea level rise. So, to cope up with this type of future natural hazard, a long term appropriate plan should be undertaken by the branch. 

 

Achievements

 

·          The scientists from the Federal Institute for Geosciences and Natural Resources (BGR), Germany in collaboration with the scientists of the Geological Survey of Bangladesh (GSB) conducted two research cruises with the German Research Vessel “Sonne” in 1994 and in 1997, aiming to unveil the geological, geophysical and hydrodynamic characteristics of the sub-aqueous part of the delta in the Quaternary Period. Other local and international organizations are also involved in conducting various researches in onshore and offshore part of the delta. Reports on the “Sonne” cruises unveiled much important geological and hydrological information of the offshore areas.

·          The branch conducted an especial project entitled “Holocene sedimentation and geomorphological characterization of the coastal areas of Bangladesh for cyclone hazard assessment and zonation” from 1998 to 2002 sponsored by the ministry of Science and Technology. The preliminary result of the project shows that the south-central coastal part is subsiding at a rate of about 4-5 mm/yr., whereas the rate is about 1-3 mm/yr. in other parts of the delta plain. The final outcome of the project provides information on the effect of sea level rise due to global warming along the coastal belt besides cyclone surge hazard areas.

·          An international seminar on “Quaternary Development and Coastal Hydrodynamics of the Ganges Delta in Bangladesh” was organized by GSB in 1999 with active participation of the branch. The seminar opened the door to the scientists of GSB to share their knowledge on the delta development and related topics with other local and international scientists.

·          About 9,500 sq. km area was mapped at medium scale of 1:50,000 till 2009 and geological reports have been prepared. Inventory maps of 36,000 sq. km were prepared at small scale of 1:250,000.