Journal - Petrography of the Siwalik sandstones, Amlekhganj-Suparitar area, central Nepal Himalaya

Petrography of the Siwalik sandstones, Amlekhganj-Suparitar area, central Nepal Himalaya

Naresh Kazi Tamrakar and Suresh Das Shrestha

1Central Department of Geology, Tribhuvan University, Kirtipur, Kathmandu, Nepal

Shuichiro Yokota

2Department of Geoscience, Shimane University, Matsue, Japan

Jour. Nepal Geol. Soc., 2003, Vol. 28, 41–56


Abstract

Middle Miocene to early Pleistocene sedimentary sequence deposited in the foreland basin of the Himalaya is represented by the Siwalik Group.  In the present study area the Siwalik Group extends in a NW-SE direction and well-exposed. Forty-four sandstone samples were studied for texture, fabric and composition in order to assess their petrographic properties and variation trends of these properties in stratigraphic levels. Sandstones were classified into sublitharenite, subarkose, lithic arenite, arkosic arenite and feldspathic graywacke and further thirteen sub-clans. Mean grain size (Mz) and Trask sorting coefficient (So) increase up-section. Recalculated quartz, matrix, modified maturity index (MMI), total cement (Ct), cement versus matrix index (CMI) and ratio of strong cement over total cement ((Cfc+Cs)/Ct) also increase, whilst packing proximity (PP), packing density (PD) and consolidation factor (Pcc) decrease up-section showing distinct trends, and therefore, these properties are promising in recognizing the older sandstones from the younger ones.

Member Login
NEWS AND EVENTS
  • May
    21

    Nepal Geological Society has organized a press meeting on the memory of 2015 Gorkha Earthquake on 2075/1/12 at the conference hall of Department of Irrigation, Jawalakhel

  • Feb
    06

    Nepal Geological Society organized a one day workshop on Earthquake Safety Day-2074 in 2074/10/13 at the conference hall of the United World Trade Center, Tripureshwor, Kathmandu, Nepal in association with Private and Boarding School Association Nepal (BAPSON Kathmandu Province).

Activities and Information

Activities of 17th and 18th Executive Committee
Nepal Geological Society
P.O.Box No. 231
Kathmandu, Nepal
FREEPHONE: +977-01-4437874
Email: info@ngs.org.np