Read : MINERALOGY

Categories
Archives

UPDATED GATE 2021 SYLLABUS

 Posted on :- 2020-08-09 10:37:38
GG Geology and Geophysics Part A: Common Section Earth and planetary system – terrestrial planets and moons of the solar system; size, shape, internal structure and composition of the earth; concept of isostasy; elements of seismology – body and surface waves, propagation of body waves in the earth’s interior; Heat flow within the earth; Gravitational field of the Earth; geomagnetism and paleomagnetism; continental drift; plate tectonics – relationship with earthquakes, volcanism and m...
READ MORE

FORAMINIFERA

 Posted on :- 2020-06-17 13:40:53
INTRODUCTION:- Micropaleontology is concerned with microfossils and nanofossils (the latter being smaller than 50 μm), the study of which must, of necessity, be carried out using the light or electron microscope. Such microfossils are:-1- The remains of unicellular and multicellular micro-organisms.2- The dissociated elements and skeletal fragments of macro-organisms. They consist of these types: Foraminifera, Ostracods, Coccolithophora, Diatoms, Radiolaria, and Dinoflagellates. Among this...
READ MORE

FAUNA OF SIWALIK GROUP

 Posted on :- 2020-06-10 16:40:18
The Shiwalik Group is well known for its wealth of vertebrate fauna, though they are confined to only certain horizons and only some of them are of biostratigraphic importance. Of added significance is the occurrence of hominoids in almost all the formations. The following list of fauna is selected from among these reported forms the different formations LOWER SHIWALIKCarnivora: Amphicycon so., ViverrachinjiensisProboscidea: Deinotherium, Gomphotherium, StegolophodonSuidae: Listriodon, Conohys...
READ MORE

Vertical electrical sounding

 Posted on :- 2020-05-17 21:47:57
A two-layer situation is encountered often in electrical prospecting. two-layer cases were interpreted with the aid of characteristic curves.  These theoretical curves, calculated for a particular four-electrode array, take into account the change in depth penetration when current lines cross the boundary to a layer with differentresistivity. The electrical boundary conditions require continuity of the component of current density J normal to the interface and of the component of electric ...
READ MORE

ALLOGENIC MINERALS

 Posted on :- 2020-04-28 13:09:25
Allogenic minerals - These are formed elsewhere and transported into the area of deposition.
READ MORE

PENETRATION TWIN

 Posted on :- 2020-04-27 21:14:38
Penetration Twins - have an irregular composition surface separating 2 individual crystals. These are defined by a twin center or twin axis. Shown here is a twinned crystal of orthoclase twinned on the Carlsbad Law with [001] as the twin axis.
READ MORE

CONTACT TWIN

 Posted on :- 2020-04-27 21:17:15
Contact Twins - have a planar composition surface separating 2 individual crystals. These are usually defined by a twin law that expresses a twin plane (i.e. an added mirror plane). An example shown here is a crystal of orthoclase twinned on the Braveno Law, with {021} as the twin plane.
READ MORE

TWIN PLANE

 Posted on :- 2020-04-27 21:04:19
Reflection across a mirror plane. The added mirror plane would then be called a twin plane.  
READ MORE

CLEAVAGE

 Posted on :- 2020-04-27 20:18:13
Cleavage. The breaking of a mineral along with a set of parallel, identical atomic planes.
READ MORE

PHYSICAL PROPERTIES OF OLIVINE

 Posted on :- 2020-04-27 20:17:14
•Form: Primatic crystals; at times as massive and compact, granular grains• Colour: Shades of green (olive green) to black•Streak: colourless• Lustre: Vitreous; transparent to translucent•Fracture: conchoidal•H: 6-7•Sp. G: 3.2 (Fo) to 4.3 (Fay)
READ MORE