Bulletin of the Department of Geology https://www.nepjol.info/index.php/BDG Official publication of the Central Department of Geology, Tribhuvan University. Full text articles available. Central Department of Geology-Tribhuvan University en-US Bulletin of the Department of Geology 1996-3491 <p>© Central Department of Geology, Tribhuvan University, Nepal</p> Geology of the Patharkhola Area, Almora District, Uttarakhand (India): With Special Reference to the Lithology and Field Relation https://www.nepjol.info/index.php/BDG/article/view/20716 <p>The Patharkhola area (longitude 79°09'E to 79°17'56''E and latitude 29°47'42''N to 29°56'69''N) covering an area of about 125 square Kms situated in Almora District,  Uttarakhand forming a part of the Almora Nappe has been selected for the detailed geological mapping at an scale of 2 cm equal to 1 Km. The rocks mainly include phyllites, schists and gneisses forming an anticlinal structure showing phyllites in the NW, S to SW and in the western part of the area, while the schists occur in the folded outcrop pattern in between both the limbs of the fold and the gneisses occur in the core of the fold. Although thin quartzitic bands has also been noticed interbedded with phyllites and schists. Several transverse faults have been noticed in the area under investigation which has been demarcated in the map.</p><p><em> </em><strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 1-6</p> Haritabh Rana Harel Thomas ##submission.copyrightStatement## 2018-08-08 2018-08-08 1 6 10.3126/bdg.v20i0.20716 Review on Practices and State of the Art Methods on Delineation of Ground Water Potential Using GIS and Remote Sensing https://www.nepjol.info/index.php/BDG/article/view/20717 <p>Due to global increase in human population, the groundwater has been extensively used to meet the water demand for domestic as well as agricultural purpose. The number of deep and shallow wells has increased exponentially. For these purpose the groundwater potential area has to be delineated so as to delineate the area for intervention for groundwater abstraction. The determination of groundwater potential with the aquifer characteristics is not always possible due to unavailability of secondary data and from financial aspect. The delineation of groundwater potential with the integration of GIS and Remote Sensing (RS) as well as with the aid of geophysical data could be an effective approach. Groundwater delineation in mountainous region uses different hydrogeologic parameters like rainfall, slope, elevation, drainage density, lineament density, lithology/geology, land use/land cover (LULC), soil, etc., whereas in case of alluvial basins, parameters like aquifer material, soil, LULC, water table, specific yield, storage coefficient, transmissivity, etc. are used. The assignment of weight for the factors and rank for their classes are important steps in the Groundwater Potential Mapping (GPM) using GIS overlay. The weights for the different parameters have to be assigned as per their role in groundwater occurrences. Different methods like Analytical Hierarchy Process (AHP), expert’s knowledge, probability weight approach,  bivariate analysis, etc. have been used for assigning weights and ranks and the predicted potential need to be validated. Generally in mountainous aquifer, spring inventory forms the basic data for the verification. In addition, the aquifer characteristics like water table, yield, transmissivity can be used for the validation in flat lands. This method of delineation of groundwater potential is found to be appropriate with acceptable accuracy. Globally, there is increasing trend in the use of GIS and Remote Sensing for the identification of groundwater potential in recent time.</p><p><em> </em><strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 7-20</p> Champak Babu Silwal Dinesh Pathak ##submission.copyrightStatement## 2018-08-08 2018-08-08 7 20 10.3126/bdg.v20i0.20717 Leaf Impressions of Terminalia (Combretaceae) and Daphnogene (Lauraceae) from the Middle Siwalik of the Chatara-Barahakshetra Area, Eastern Nepal https://www.nepjol.info/index.php/BDG/article/view/20719 <p>Leaves of <em>Terminalia </em>(Combretaceae) and <em>Daphnogene </em>(Lauraceae) are described from the lower member of Lower Siwalik of Chatara- Barahakshetra area, eastern Nepal. The habit, habitat and present day distribution of the comparable extant taxa indicates the existence of tropical to sub-tropical evergreen to semi evergreen forest with humid climate in the area during the deposition of the Siwalik sediments.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 21-28</p> Purushottam Adhikari Gaurav Srivastava Rakesh C. Mehrotra Drona Adhikari Keshav Shrestha Dieter Uhl Khum N. Paudayal ##submission.copyrightStatement## 2018-08-08 2018-08-08 21 28 10.3126/bdg.v20i0.20719 Geological Study of the Lesser Himalaya in the Kusma-Baglung Area, Western Nepal https://www.nepjol.info/index.php/BDG/article/view/20721 <p>Geological study was carried out along the Kaligandaki and Modi Khola valleys in west Nepal. The area comprises the rock of Lesser Himalayan metasedimentary sequence. Main rock types present in the area are quartzite, phyllite, metasandstone and psammatic phyllite. Schist and gneiss are present in some parts. Ulleri Gneiss is explored in the area. Kusma-Baglung area comprises the spectacular terrace deposits formed at the Quaternary time by the Kaligandaki River and the Modi Khola. The terrace extensively comprises clast of limestone, marble, gneiss, quartzite, schist, phyllite ranging in size from fine matrix to huge boulders derived from the Higher Himalaya.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 29-36</p> Nawraj Sapkota Lalu P. Paudel ##submission.copyrightStatement## 2018-08-08 2018-08-08 29 36 10.3126/bdg.v20i0.20721 Vegetation and Climate Around 780 Kyrs BP in Northern Kathmandu Valley, Central Nepal https://www.nepjol.info/index.php/BDG/article/view/20722 <p>Palynological study from the Dharmasthali Formation exposed in the northern part of Kathmandu valley revealed the composition of forest vegetation that were growing in middle Pleistocene (780 kyrs BP) in this area. In a total fifteen samples were collected from the 46 m exposed section for the palynological study. The profile can be divided into two zones on the basis of pollen assemblages. The lower part (DF-I) is dominated by Pteridophyte spores such as <em>Lygodium, Polypodium, Cyathea </em>and <em>Pteris</em>. The dominance of Pteridophytes indicate that the forest floor was moist and humid. The tree pollen consists of <em>Abies, Pinus, Quercus, Podocarpus </em>and <em>Alnus</em>. Other Gymnosperms such as <em>Picea </em>and <em>Tsuga </em>were represented by very low percentage. Poaceae and Cyperaceae show their strong presence indicating grassland and wetland conditions around the depositional basin. In the upper zone (DF-II) there is increase of Gymnosperms such as <em>Picea </em>and <em>Abies</em>. The subtropical Gymnosperm <em>Podocarpus </em>decreased while <em>Tsuga </em>completely became absent in this zone. Cold climate preferring trees such as <em>Cedrus, Betula, Juglans </em>and <em>Ulmus </em>appeared first time in this zone. The climate became even colder and drier in the upper part of the section. Near water plants such as Cyperaceae and <em>Typha </em>show their dominance in this zone. The plant assemblages from bottom part of the Dharmasthali Formation indicate warm climate condition which was becoming colder after 780 kyrs towards the top part of the sequence.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp:37-48</p> Sima Humagain Khum N. Paudayal ##submission.copyrightStatement## 2018-08-08 2018-08-08 37 48 10.3126/bdg.v20i0.20722 Geological Study of Chatara–Barahakshetra Section, Sunsari-Udayapur District, Eastern Nepal https://www.nepjol.info/index.php/BDG/article/view/20723 <p>Geological mapping was carried out in the Chatara–Barahakshetra area of east Nepal. The Siwalik of the Chatara–Barahakshetra area is divided into the Lower Siwalik and the Middle Siwalik. Each unit is further subdivided into lower and upper members. The Central Churia Thrust is overturned in the study area. Highly deformed Siwalik contain several outcrop-scale as well as a large-scale folds.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 49-58</p> Drona Adhikari Keshav Shrestha Purushottam Adhikari Khum N. Paudayal Lalu Paudel ##submission.copyrightStatement## 2018-08-08 2018-08-08 49 58 10.3126/bdg.v20i0.20723 Geology and Mineral Resources of Phalamdada-Dhuwakot Section of West-Central Nepal, Lesser Himalaya https://www.nepjol.info/index.php/BDG/article/view/20724 <p>Geological mapping was carried out along the Phalamdanda-Dhuwakot section of west-central Nepal in the Lesser Himalaya. The aim of geological mapping was to prospect the metallic mineral resources in the area especially to assess the geological control of mineralization as prognostic mapping and study the genesis of mineralization. The area has developed low-grade metamorphic rocks of the Nawakot Group. Geological rock units like the Kuncha Formation, Fagfog Quartzite, Dandagaon Phyllite, Nourpul Formation and Dhading Dolomite are mapped in the area. Jal Bhanjyang Thrust carries the more older rocks of the Nourpul Formation over the Dhading Dolomite. The area is highly deformed as indicated by presence of folds. Outliers of Fagfog Quartzite and Dhading Dolomite are developed at the core part of the syncline. Phalamdada iron and Anbu Khaireni as well as Dharapani copper are the major metallic deposits reported in the area. Both deposits are considered as the syngenetic in nature.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp:59-64</p> Arjun Bhattarai Kabiraj Paudyal ##submission.copyrightStatement## 2018-08-08 2018-08-08 59 64 10.3126/bdg.v20i0.20724 Geotechnical Properties of the Fagfog Quartzite for Curved-Cuts along Mugling Narayanghat Road Section https://www.nepjol.info/index.php/BDG/article/view/20725 <p>Slope cutting in hard and steep slopes are very difficult task. In Mugling-Narayanghat road section, near Mugling, hard quartzite rock was obstructing road expansion because of vertical slope. In the area rock of the Fagfog Quartzite is present which has very good geotechnical properties. In the area, rock mass classifications was carried out using RMR, Q and GSI where maximum and minimum rock mass class values are II and I respectively. Other properties of the area like unit weight (γ), uniaxial compressive strength (σci), Young’s modulus (Ei), Poisson’s ratio (ν) and RQD were also calculated according to the rock mass classification. The slope was designed in such a way that the maximum stability for minimum excavation. All the analysis were carried out in numerical modeling using FEM, as much as possible replicating real ground condition. From the analysis total displacement at suitable cut angles was determined.</p><p><strong> Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 65-70</p> Sarmila Paudyal Suman Panthee ##submission.copyrightStatement## 2018-08-08 2018-08-08 65 70 10.3126/bdg.v20i0.20725 Upper Pliocene to Lower Pleistocene Plant Microfossils from The Basal Part of the Lukundol Formation (Southern Kathmandu Valley) and Their Climatic Implications https://www.nepjol.info/index.php/BDG/article/view/20726 <p>The Late Pliocene to Lower Pleistocene fluvio-lacustrine sediments of the Lukundol Formation distributed in the southern part of the Kathmandu Basin, consists of various fossils of flora and fauna which are very useful proxies to reconstruct the past climate. Twenty seven samples were collected for palynological study from different beds of the Lukundol Formation exposed in the Pharsidol area due to recent road cut. The exposure is about 100 m thick. The study revealed the dominance of gymnosperms over angiosperm plants. On the basis of the pollen assemblage, the Lukundol Formation could be divided into three different pollen zones namely PD-I, PD-II and PD-III. The variation in the climate observed in these three zones indicates that the climate of the Kathmandu valley during the deposition of the Lukundol Formation was not uniform. The climate had been warmer in the lower and upper zones while colder in the middle zone than today.</p><p> <strong>Bulletin of Department of Geology,</strong> vol. 20-21, 2018, pp: 71-81</p> Maria Maharjan Sima Humagain Khum N. Paudayal ##submission.copyrightStatement## 2018-08-08 2018-08-08 71 81 10.3126/bdg.v20i0.20726 Seismicity of Nepal and the Surrounding Region https://www.nepjol.info/index.php/BDG/article/view/20727 <p>This study updates an earthquakes catalogue (in terms of surface-wave magnitude, Ms≥4.0) for Nepal and the surrounding region (26°-31.7° N, 79°-90° E) covering the period from 1255 to 2015 and analyze the spatio-temporal distribution patterns of seismicity. The spatial distribution of all catalogued earthquakes indicates that earthquakes are unevenly distributed in Nepal and the surrounding region with distinctly higher earthquake activity in the far western and eastern parts of Nepal than the southern part of the country. The temporal distribution of updated seismicity data (1255-2015) indicates that there are very little accounts of significant earthquakes prior to 1800. Furthermore, the temporal trend of the updated seismic catalogue clearly demonstrate the gradual increase in earthquake data during the time window 1801-1963 and considerable increase in number and quality of seismic events predominantly from 1964 onwards.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 83-86</p> Dilli Ram Thapa ##submission.copyrightStatement## 2018-08-08 2018-08-08 83 86 10.3126/bdg.v20i0.20727 Community Based Flash Flood Early Warning System: a Low-cost Technology for Nepalese Mountains https://www.nepjol.info/index.php/BDG/article/view/20728 <p>Every year, flood impose substantial economic, social and environmental cost on Nepalese community through direct damage to residential, commercial, educational and structures. Moreover, the flood destroys animal farm, commercial stock and records and other content of the building and pollutes the water. Early Warning Systems are important to save such lives and properties which involves computer, satellite data and high accurate operating system but this system is very costly in terms of installation as well as operation and maintenance leading to hindrance in the sustainability of the system. However, high-tech technology is very expensive and not feasible in Nepal and therefore low-cost and easy operating system is needed in the rural parts of Nepal. The system includes Solar panel, Siren, Ultrasonic sensor, processing unit, and battery. The ultrasonic sensor sense water level and the siren will automatically start. The threshold can be set up according to the space and time.</p><p> <strong>Bulletin of Department of Geology</strong>, vol. 20-21, 2018, pp: 87-92</p> Basanta Raj Adhikari Nagendra Raj Sitoula ##submission.copyrightStatement## 2018-08-08 2018-08-08 87 92 10.3126/bdg.v20i0.20728