http://ir.lib.ruh.ac.lk/handle/iruor/7367 Sat, 25 Apr 2026 19:31:40 GMT 2026-04-25T19:31:40Z http://ir.lib.ruh.ac.lk/handle/iruor/9150 Global Blue Economy Analysis Developments and Challenges Cooray, N.S.; Premarathne, U.; Atapaththu, K.S.S.; Priyadarshana, T. Oceans are approximately three- quarters of the earth’s surface, accountable for more than 90% of the biosphere, providing an array of goods and services to the global community which includes food, employment, recreation and cultural well- being, minerals, oxygen production, greenhouse gas absorbance, climate change impact mitigation, and serve as highways for seaborne international trade (United Nations, 2017). For the development of economies along with the threats posed by the climate change and global warming the concept of the Blue Economy was first introduced in 1994 by Professor Gunter Pauli of the United Nations University (UNU). Because of this significant role played by the oceans, the importance of implementing sustainable development measures for marine environment was discussed at the United Nations Conference on Sustainable Development (Rio+ 20) held in Rio de Janeiro, Brazil in June 2012. Consequently, the conference adopted a set of ground- breaking guidelines on green economic policies which are considered as essential tools for achieving sustainable development goals (United Nations, 2012). With strong support from coastal and island nations at the conference, because of the contribution made by the oceans to their economies, the ocean derived green economy was accepted as the blue economy. Sat, 01 Jan 2022 00:00:00 GMT http://ir.lib.ruh.ac.lk/handle/iruor/9150 2022-01-01T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/9148 Revelation of depositional features in the Paleocene and Eocene in the Mannar basin using amplitude analysis of a 3D data set Dushyendra, A.; Premarathne, U.; Weerasinghe, D. The Mannar Basin is located between the western coasts of Sri Lanka and the southern coast of India. The Sri Lankan portion of the basin extends over 45,000 km2. It is a deep-water frontier with only two natural gas discoveries. Studies show that the Paleogene and the Late Cretaceous sections have potential hydrocarbon reservoirs. However, little is known regarding their depositional features. The objective of this study was to understand the depositional features in the Paleocene and Eocene sediments in the M2 exploration block in the Mannar basin using a three-dimensional seismic volume. IHS Kingdom software was used for seismic data interpretation. The root mean square amplitude was used to characterise sediment facies in seven time windows having 50-millisecond intervals. The results show the occurrence of an interpreted turbidite fan system in the Paleocene and Eocene sections. A NE-SW trending deep-water canyon channel system occurs in the early Eocene section. Sat, 01 Jan 2022 00:00:00 GMT http://ir.lib.ruh.ac.lk/handle/iruor/9148 2022-01-01T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/9146 Reservoir potential of the Campanian sandstone in the Dorado North well on the Mannar Basin, offshore Sri Lanka Bandara, M.; Premarathne, U. The Mannar Basin is located offshore in between the west coast of Sri Lanka and the east coast of India. It is a Mesozoic failed rift basin filled with Late Jurassic to recent sediments. The basin is one of the main targeted areas for oil and gas exploration in Sri Lanka. In 2011, the existence of an active petroleum system in the basin was confirmed by discovering natural gas from Dorado and Barracuda wells. Although the petroleum system of the Mannar Basin is known to some extent, the porosity and permeability of potential reservoirs in the basin are little known. Previous basin modeling studies have reported that the Late Cretaceous section in the northern part of the Mannar Basin has potential reservoirs. However, their porosity and permeability have not been investigated in detail due to the lack of availability of well data. The objective of this study was to estimate the porosity of approximately 431 m thick Late Cretaceous (Campanian) sandstone section in the Dorado-North well, located on the northern part of the Mannar Basin. The results show that the Campanian section is mainly composed of shaly sandstone. Almost half of the section shows very good reservoir potential, while the rest of the section has fair to good reservoir potential. The quality of a hydrocarbon reservoir depends on its shale fraction. Shale degrades the reservoir quality. Caving in give rise to uncertain data in petrophysical logs. The Campanian section in the Dorado-North has very good hydrocarbon potential. Fri, 01 Jan 2021 00:00:00 GMT http://ir.lib.ruh.ac.lk/handle/iruor/9146 2021-01-01T00:00:00Z http://ir.lib.ruh.ac.lk/handle/iruor/9143 Continental flood basalt magmatism contemporaneous with Deccan traps in the Mannar basin, offshore Sri Lanka Premarathne, U.; Ranaweera, L.V. The Gulf of Mannar and adjoining Cauvery basin to the north between India and Sri Lanka are associated with a failed rift, which initiated during the late Jurassic to early Cretaceous as a precursor to the breakup of East Gondwana. Despite the occurrence of igneous rocks that can be noted in seismic profiles, offshore, and deep seated occurrence of those have lead only to the limited understanding of igneous activity in the Mannar basin. Rock cuttings recovered in the Barracuda exploratory well in the Mannar basin shows approximately 700 m thick basalt rock sequence interlayered with sediments at a depth of 3500–4200 m below mean sea level. Here, we analyzed samples recovered from the Barracuda well for major and trace element composition. Major and trace element data suggest that the basalts were crystallized from two different degrees of partial melts from a similar source. Chondrite normalized rare earth element (REE) patterns indicate that the basalts are similar to continental flood basalt, though they show a distinct Ba positive anomaly. Importantly, supported with previously available K–Ar data, we decipher that these basalts are contemporaneous with the Deccan traps. Rifting between Seychelles and India which had occurred at 62 Ma approximately 3.5 Ma after the main Deccan eruption is synchronous with the Barracuda volcanism suggesting coeval rifting between Seychelles–India and India–Sri Lanka. Thus, our data suggest simultaneous rifting between Seychelles–India and India–Sri Lanka. Large plate reorganizations that took place during this time period in the Indian Ocean have likely caused consequent passive rifting in the Mannar basin. Fri, 01 Jan 2021 00:00:00 GMT http://ir.lib.ruh.ac.lk/handle/iruor/9143 2021-01-01T00:00:00Z