Presentation on theme: "BY: AMIT RANJAN 66/13 NITISH KUMAR 69/13 PRABHAKAR KR. 71/13."— Presentation transcript:
BY: AMIT RANJAN 66/13 NITISH KUMAR 69/13 PRABHAKAR KR. 71/13
OVERVIEW ABOUT HYDROTHERMAL DEPOSITS CONDITION FOR FORMATION SHAPE AND SIZES OF DEPOSITS DEPOSITS IN INDIA REFERENCE
WHAT IS IT??? This is a distinct group of economic minerals, which has been formed from cooling of gaseous and liquid solutions in cavities, fissures or pore spaces of the rocks, i.e., wherever these solutions find a place to enter.
When hot magma resides in the crust, water in the surrounding rock is heated and begins to convect. As it travels, the hot water dissolves materials (ions) from the surrounding rock and carries them to new locations. If the conditions of the water change (temperature, pressure, pH, oxygen content), new minerals will precipitate.
CONDITIONS FOR THE FORMATION…..!!! HIGHLY ACTIVE AND ENRICHED FLUIDS SUITABLE PATHWAYS PHYSICO-CHEMICAL ENVIRONMENT
SSUPERHEATED STEAM It is the first condition of formation of hydrothermal deposits which we necessarily take in common as HIGHLY ACTIVE AND ENRICHED FLUIDS. The steam is capable of containing within it, in dissolved form, metallic elements like gold, copper, tungstun etc. These elements are crystallised out as the enriched solution pass upwards and suffer cooling and loss of pressure.
SSUITABLE PATHWAYS… The point itself suggest what we are talking about…….PATHWAYS…..which means the way in which fluid travels. It has two main characters:- Primary – It includes bedding planes, porosity and jointing structures. Secondary – It includes faults, solution cavities and fissures.
PPHYSICO-CHEMICAL ENVIRONMENT…. Responsible for deposition of economic minerals from the hydrothermal solution. Change in temperature and pressure. Ensuring chemical reactions between various components present within these liquid – gas solution. Chemical reactions between the components of the solutions and those of country rock.
SHAPE AND SIZES OF DEPOSITS 1. Fissure-veins : Mineral bodies are of elongated and tabular shape oriented. 2. Ladder veins :Mineral deposits are in roughly regulaly spaced fractures (like ladder).
3. Gash-veins : Deposits are narrow, sloping and thick-bodies of minerals deposited in solution-fissures and cracks of host rock. 5. Saddle-Reefs : Mineralized cavities associated with the folded rocks comprising beds of competent and incompetent nature. 4. Stock works : Deposits are small in size, large in number and within a limited space, traversing the body of rock.