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Explore the Earth, Maps and Satellite Images

Google Maps and Google Earth are very common platforms today to explore maps and satellite images of the earth. But there are many other ways to explore the earth. Some are listed here.  1.   Earth Explorer This map is developed by USGS helpful to obtain earth imagery across available geo-spatial data types. Users can navigate via interactive map or text search to obtain Landsat satellite imagery, Radar data, UAS data, digital line graphs, digital elevation model data, aerial photos, Sentinel satellite data, some commercial satellite imagery including IKONOS and OrbView3, land cover data, digital map data from the National Map, and many other datasets. Users can search by exact location via the interactive map or input specific coordinates to view what data types are available. 2.   Sentinel Hub This platform developed by  Sinergise has Sentinel, Landsat, and other Earth observation imagery easily accessible for browsing, visualization and analysi...
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Biostratigraphy

  Biostratigraphy.  The element of stratigraphy that deals with the distribution of fossils in the stratigraphic record and the organization of strata into units on the basis of their contained fossils. Biostratigraphic classification.  The systematic subdivision and organization of the stratigraphic section into named units based on their fossil content. Biostratigraphic zone (Biozone).  A general term for any kind of biostratigraphic unit regardless of thickness or geographic extent.   Biozones vary greatly in thickness, geographic extent, and represented time span. Biostratigraphic horizon (Biohorizon).  A stratigraphic boundary, surface, or interface across which there is a significant change in biostratigraphic character.  A biohorizon has no thickness and should not be used to describe very thin stratigraphic units that are especially distinctive   Kinds of Biostratigraphic Units Five kinds of biozones are in common use: range zo...

Himalayan range, Himalayan Orogen, and Himalayan tectonic system

According to Yin 2006, the Himalaya has been politically, geographically, structurally, and stratigraphically defined. Geographically, the Himalayan range lies between its eastern and western syntaxis as represented by the Namche Barwa and Nanga Parbat peaks. The Himalayan orogen is defined by the Indus– Tsangpo suture in the north, the left-slip Chaman fault in the west, the right-slip Sagaing fault in the east, and the Main Frontal Thrust (MFT) in the south. The Himalayan tectonic system is a broader concept than the Himalayan orogen. It consists of the Himalayan orogen, the active Himalayan foreland basin (=Indo-Gangetic depression), and the Indus and Bengal Fans. All of these features were produced by the Indo-Asian collision.

Fossils from Nepal Himalaya

  Siwalik Fossils Plant fossils, Vertebrate fossils and ostracods. Vertebrate fossils have been recorded from Babai, Tui, Surai, Tinau and Rato Khola area. 2. Plant fossils in Lower Siwalik and correlable rocks. •         Bambusa siwalika •         Polyalthya palaeosimiarum •         Dipterocarpus siwalikus 2.       Fresh water Ostracods from Butwal area. Fossils of Tansen Group Sisne : Bryozoa; Genera Fenestella, Polypora, Acantholcladia ( Carboniferous to Permian) Taltung : Bennettitales and Ficlaes. Ptilophyllum sp., Pterophyllum sp., Cladophrebis sp., Elatocladus sp, Pterodospermae ( L. Jurrasic to E. Cretaceous) Amile : Shark teeth, vertebrate bone fragments, gastropods, pelecypods, echinoids Bhainskati : Nummulites and Assilina, Bivalves, vertebrate bone fragments. Dumri :...

Main Central Thrust

  •         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 •   ...

IUGS Classification of Igneous Rocks!!

 

GEOLOGICAL HISTRORY OF NEPAL HIMALAYA

  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. • ...

Magmatism in Nepal Himalaya

  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...

Popular posts from this blog

Explore the Earth, Maps and Satellite Images

Google Maps and Google Earth are very common platforms today to explore maps and satellite images of the earth. But there are many other ways to explore the earth. Some are listed here.  1.   Earth Explorer This map is developed by USGS helpful to obtain earth imagery across available geo-spatial data types. Users can navigate via interactive map or text search to obtain Landsat satellite imagery, Radar data, UAS data, digital line graphs, digital elevation model data, aerial photos, Sentinel satellite data, some commercial satellite imagery including IKONOS and OrbView3, land cover data, digital map data from the National Map, and many other datasets. Users can search by exact location via the interactive map or input specific coordinates to view what data types are available. 2.   Sentinel Hub This platform developed by  Sinergise has Sentinel, Landsat, and other Earth observation imagery easily accessible for browsing, visualization and analysi...

Geological Maps of Nepal

 List of geological maps different parts of Nepal . 1. Geological Map of Nepal 2.  Geological Maps Of Seven Provinces, Nepal 3.  Photogeological Map of Central Nepal (Stocklin and Bhattarai, 1982). 4. Geological maps of 1:50,000  of different parts of Nepal published by DMG. 5. Engineering Geological and Environmental maps of different cities of Nepal published by DMG. 6.  Mineral Resources map of Nepal 7.  Epicenter map of Nepal Himalaya

Historical Earthquakes of Nepal

This is the list of some historical earthquakes of Nepal compiled from various sources. References: National Society for Earthquake Technology-Nepal (NSET) Pandey, M.R. & Molnar, P. (1988). "The Himalaya, its tectonic environment, and seismicity" Tiwari, Sudarshan. (1992). "The Brick and the Bull: An Account of Handigaon" Bilham, R. et al. (1995). "The Kathmandu Valley earthquakes of 1833 and 1834" Ambraseys, N.N. & Douglas, J. (2004). "Magnitude Calibration of North Indian Earthquakes" United States Geological Survey (USGS) Earthquake Information Bajracharya, B. (2001). "Earthquake Risk Reduction in Nepal" Udayapur Earthquake: NSET Report, 1990 Government of Nepal, National Planning Commission (2015). "Post-Disaster Needs Assessment" UN Office for the Coordination of Humanitarian Affairs (OCHA), 2015 Gorkha Earthquake United Nations Development Programme (UNDP), 2015