Shahina Tariq

Evaluation of excessive lifetime cancer risk due to natural radioactivity in the rivers sediments of Northern Pakistan

Abstract Naturally occurring radionuclides 226Ra, 232Th and 40K present in the rivers sediments of Northern Pakistan were measured using HPGe γ-ray spectrometer to evaluate the radiation health hazard indices and excess lifetime cancer risk (ELCR). Average concentrations of 226Ra, 232Th and 40K in the sediments were found to be 50.66±1.29, 70.15±1.45 and 531.70±5.45Bqkg−1 respectively. Radium equivalent activity (190.89Bqkg−1), outdoor external dose (87.47nGyh−1), indoor external dose (165.39nGyh−1), and total average annual effective dose (0.92mSv) were calculated. The hazardindices are higher than the worlds average values. Total excess lifetime cancer risk (ELCR) was found to be 3.21×10−3 which is relatively higher. Numerous cancer deaths are annually reported from the Northern areas of Pakistan, which may be related to high radioactivity in the area.

Analysis of Landslides Triggered by October 2005, Kashmir Earthquake.

Introduction: The October 2005, Kashmir earthquake main event was triggered along the Balakot-Bagh Fault which runs from Bagh to Balakot, and caused more damages in and around these areas. Major landslides were activated during and after the earthquake inflicting large damages in the area, both in terms of infrastructure and casualties. These landslides were mainly attributed to the minimum threshold of the earthquake, geology of the area, climatologic and geomorphologic conditions, mudflows, widening of the roads without stability assessment, and heavy rainfall after the earthquake. These landslides were mainly rock and debris falls. Hattian Bala rock avalanche was largest landslide associated with the earthquake which completely destroyed a village and blocked the valley creating a lake. Discussion: The present study shows that the fault rupture and fault geometry have direct influence on the distribution of landslides and that along the rupture zone a high frequency band of landslides was triggered. There was an increase in number of landslides due to 2005 earthquake and its aftershocks and that most of earthquakes have occurred along faults, rivers and roads. It is observed that the stability of landslide mass is greatly influenced by amplitude, frequency and duration of earthquake induced ground motion. Most of the slope failures along the roads resulted from the alteration of these slopes during widening of the roads, and seepages during the rainy season immediately after the earthquake. Conclusion: Landslides occurred mostly along weakly cemented and indurated rocks, colluvial sand and cemented soils. It is also worth noting that fissures and ground crack which were induced by main and after shock are still present and they pose a major potential threat for future landslides in case of another earthquake activity or under extreme weather conditions.

Landslide Susceptibility Analysis in Arandu Area Shigar Valley, CKNP (Gilgit-Baltistan- Pakistan)

The Pakistani Gilgit-Baltistan are recognised as being one of the most beautiful and interesting places in the world due to the presence of the longest glaciers and the highest reliefs. This area remained remote and inaccessible before 1965, after which began the construction of the first roads (Karakoram Highway—KKH). In 1992, the Pakistani Government delegated the responsibility for initiating a preliminary survey to outline the borders of the Central Karakoram National Park (CKNP) which allowed a preliminary outline of the borders (about 3000 km2) where the major mountain massifs (as Mt. K2), watersheds, and glaciers were included. Since then, several proposals followed. With the aim of preserving this natural beauty for future generations as well as providing the CKNP of a Management Plan, a 5-year multidisciplinary project called SEED (Social, Economic, Environmental Development) started. One of the project’s objectives was the analysis of the landslide geohazards aiming at the implementation of a landslide inventory and the realization of a susceptibility map. The Arandu village and its surroundings, which is part of Shigar valley, where the Chogolungma glacier is, was chosen as pilot area. During the summer survey had in 2012, part of the landslide-prone areas, previously identified through DEM analysis (derived from ASTER and Remote Sensing (RS) images) and GIS techniques were identified validating the obtained maps. The Analytical Hierarchy Process (AHP) was used to extract the factor weights in a pairwise comparison matrix. Frequency ratio (FR) method was adopted to drive each class weight. The Weighted linear combination was used in the end to determine the landslide susceptibility index value (LSI).