Nepal: Geology and Geography

  •         First recognized by Heim and Gansser (1939) based on observations made along Garhwal and   Kumaun regions of India. •    Crops out along  2200 km length of the Himalaya from western Zanskar to Bhutan and Arunachal Pradesh •         Intracrustal thrust that dips northward Variable Definations: •         Heim and Gansser (1939); it marks the lithological difference between the Lesser Himalayan rocks (below) and the Higher Himalayan rocks (above)  •         Le Fort 1975; it denotes an abrupt change in metamorphic grade •         Arita 1983; Searle et al. 2003, 2008 : the fault defines the top or basal surface of several kilometer-thick shear zone across the lowermost part of the Higher Himalayan rocks and the uppermost part of the Lesser Himalayan sequence •   ...

 

  GEOLOGICAL HISTRORY OF NEPAL HIMALAYA •         Himalaya was formed by the collision of Indian Plate with Eurasian Plate around 55 million years ago. •         The major events in the geological history of Himalaya are well recognizable in Nepalese sector. They are: Sedimentation in the Purana Sea, Pan African Diastrophism, Sedimentation in Paleothethys, Hercynian Diastrophism, Gondwana Sedimentation, Sedimentation in Neotethys, beginning of Himalayan Orogeny, formation of foreland basin and tremendous rise of Himalaya A. Precambrian Events •         Deep and Shallow marine sedimentation in Purana Sea. •         Wide distribution of Precambrian rocks in LH and HH. •         Very early during Paleozoic, there was a very wide sea covering the vast territory of LH and the central and northern parts of India. • ...

  a.      Tertiary rocks in Siwalik Hypabyssal basic magmatic sills and dykes in Middle and Lower Siwalik, Central Nepal Dolerite in Marine Khola section, small basic rock bodies (Basaltic) along Dwar khola section b.      Precambrian Felsic Rocks: -In Higher Himalaya, MCT zone and the Lesser Himalayan Crystalline thrust sheets -Synsedimentary feldspathic augen gneiss L to M Paleozoic age of Ulleri Augen gneiss Ulleri gneiss in the MCT zone is the most thickest band in the Himalaya (about 1500 m thick) and extends to entire length of the Himalaya, often associated with granites and pegmatites.   c.       Permian Basalts: Aulis Volcanics at Tansen area palpa. Composition: between tholeiitic and alkalic basalt compositions   d.      Precambrian mafic rocks (Greenschist and amphibolites).   As supracrustal dikes and sills, intruded in Precambrian Nawakot Complex...

  Initial surveys along widely spaced profile lines covering large areas for regional geology and enable plan of detail follow up survey. Detail reflection survey in areas of interest/prospective targets found from initial stage.It involves closely spaced profile lines and high density of profile intersection to define useful structures. Initial interpretation involves structural mapping to identify structural closures and the identified closures need a second round of detail survey to select location of exploration borehole. 3D survey may be used if unsoed by 2D data. Exploration boreholes are sited on seismic lines sp borehole logs can be correlated directly with local seismic stations. Refinement of seismic data from additional seismic profiles. Seismic modelling can be used to obtain detailed information on geometry of reservoir and internal lithological variation that may affect HC yield. 4D surveys can detect unexploited arrears in a producing field.

Geologic hazards are naturally-occurring phenomena capable of causing loss or damage. Risk is the potential to a negative consequence that exposure to the hazard will lead. Risk may be as loss of life or economic loss.  Examples: Nepal has a number of faults that may produce earthquakes anytime. Some of these faults are located in populated regions, so the people in those areas at Risk while other faults located in remote areas with few peoples and structures. The hazard may be the same for the two different areas but the regional risk differs because the potential impact is greater in the more populated area. Town A and Town B are right next to the same earthquake fault. They have the same earthquake hazard. But they don't have the same risk, because Town A has buildings built to withstand earthquake ground shaking and Town B does not. If you are Town B, you have two things you can do to reduce your risk of being hurt or killed in an earthquake. You can build to withstand e...

#The ternary.TernaryAxesSubplot is used to create the ternary plot within a matplotlib figure. #make sure you have installed matplotlib import matplotlib.pyplot as plt import ternary # Example data points (Q, F, R) data = [(93.75, 2.0, 3.8), (85, 5, 10), (88.75, 3.75, 7.5), (90, 6, 4), (82.5, 6.3, 11.3), (88.3, 3.9, 7.8), (81.8, 10.4, 7.8), (85.2, 9.1, 5.7), (88.9, 6.2, 4.9), (79.2, 11.7, 9.1), (79.5, 13.7, 6.8), (70, 20, 10)] #reorder data as (R,Q,F) to plot as standard triangle with Q on top reordered_data = [(c, a, b) for (a, b, c) in data] # Scale of the ternary plot (percentage: 0 to 100) scale = 100 # Set up the figure and the ternary subplot figure, ax = plt.subplots(figsize=(8, 7)) tax = ternary.TernaryAxesSubplot(ax=ax, scale=scale) # Add the boundary and gridlines tax.boundary(linewidth=1.5) tax.gridlines(color="gray", multiple=10, linewidth=0.5) # Set axis labels fontsize = 11 tax.bottom_axis_label("Rock Fragments (%)", fontsize=fontsize) tax.le...

  Geology and Python: A Powerful Pair Geology is the study of Earth—its structure, history, and the processes shaping it. Traditionally, geologists used maps, fieldwork, and lab tools to understand our planet. Now, with the rise of technology, Python has become an essential tool for modern geologists. Python is a programming language known for being easy to learn and highly useful. Here’s how it helps in geology: Data Analysis : Geologists deal with lots of data, like seismic records or mineral samples. Python helps organize and analyze this data quickly. Visualization : With Python, geologists can create graphs, maps, and even 3D models to better understand their findings. Mapping : Python tools like GeoPandas make it easier to map faults, study terrain, and analyze locations. Prediction : Using machine learning in Python, geologists can predict events like landslides or identify areas rich in minerals. Modeling : Python helps simulate Earth processes like earthquakes, erosion, an...

The landslide is located at Lamuni-Danpur area, Purchaudi Municipality-8 of Baitadi District, Sudurpaschim Province. The Lamuni-Danpur landslide covers about 0.8 sq.km as traced on recent google image. Three villages, Lamuni on east, Danpur on west and Tudet on north are affected due to landslide. As per locals, the landslide is more than 100 years old. About 110 houses have been shifted till now along with loss of cultivable land. The landslide covers forest area of two community forests, Gopeswor Community Forest, Lamuni and Devsthal Community Forest, Danpur. Kedar temple lies about 90m away from the south west part of the landslide. Presently, the landslide is extending toward the Lamuni Village. Some crown cracks has been developed Nearby Lamuni Village. The people residing there are posing great threat of landslide. The lithology within landslide was dominated by light grey to green phyllite with some quartzite and schist. The Phyllite Unit is overlain by Quartzite and Schist Un...