Shukla Acharjee

By Biswajit Nath, Zheng Niu and Shukla Acharjee

Pre-earthquake anomaly detection and assessment was performed in the present study through lineament changes observation by using multitemporal Landsat 8 OLI satellite imageries. These data found convincing results to identify relevant anomalous variations prior to the two recent earthquakes, that is, Gorkha of Nepal 7.8 Mw (major) (25 April 2015) and Imphal of Manipur (eastern India) 6.7 Mw (strong) (4 January 2016) compared with normal behavior in the absence of earthquake. Epicenter-based single tile of five multitemporal Landsat 8 OLI data was considered for each case, where one image was considered to show the normal behavior of lineament (in the absence of earthquake) and three for anomalous behavior prior to earthquake (in the presence of earthquake), and the rest one used to represent post-earthquake behavior (in the absence of earthquake), respectively. The derived lineament data were used further in different forms to observe pre-earthquake anomalies. The research results witnessed major changes of lineaments and observed anomalies prior to the two impending earthquakes while it was observed normal behavior in the absence of earthquake event. The results obtained using the automated and geo-integrated techniques help us to detect earthquake in advance prior to its strike could be used an alternative method in worldwide for future earthquake monitoring.

Part of the book: Multi-purposeful Application of Geospatial Data

By Davidson E. Egirani, Mohd T. Latif, Nanfe R. Poyi, Napoleon Wessey and Shukla Acharjee

Iron oxides are chemical complexes which occur naturally, comprising iron and oxygen. Here, together, 16 types of iron oxides and oxyhydroxides have been identified. These two components of oxides are widely spread naturally. They are vital to humans and useful in most geological and biological activities. In addition, they are useful as pigments and catalyst in industries and hemoglobin in blood circulation. The interplay and conversion of these components from one form to another are essentially controlled by bacterial species. These contain 70 and 72% iron, respectively. Furthermore, iron ores are classified in terms of occurrence. Banded iron formation (BIF) comprises 15% iron, comprising minerals of iron that are bedded besides silica. Beneficiation processes of iron ore generate dust in the atmosphere, acid mine drainage in the ecosystem and metallic iron for steelmaking. Beneficiation process requires dissolution of minerals surrounding the ore and the release of metals and cement matrix into water courses. These generates acid leading to acid mine drainage. Therefore, there is a need for impact assessment of the environment in the planned beneficiation cycle. Sustainable beneficiation must be done to reduce impact on the natural, social or economic environment.

Part of the book: Iron Ores and Iron Oxide Materials