When almost all the elevated portions are worn down by river erosion reducing an area to almost a plain region, it is termed as Peneplain. Peneplain is a region that is almost a plain. It is formed due to erosion by rivers and rain, that continues until almost all the elevated portions are worn down; the most resistant rocks generally stand above the general level of the land.
India broke away from Australia and Antarctica and started moving north in the period of ________
India broke away from Australia and Antarctica and started moving north in the period of Cretaceous. The Cretaceous began 145.0 million years ago and ended 66 million years ago. Most Cretaceous rocks are not chalks, but most chalks were deposited during the Cretaceous.
Nappe, in geology, large body or sheet of rock that has been moved a distance of about 2 km (1.2 miles) or more from its original position by faulting or folding. An extremely folded structure in which the motion of thrust fold overrides the adjacent rock structure is called Nappes. These are found at convergent plate boundaries. Example:- The Himalayan Nappes in Uttarakhand & Nepal.
Sandstone is one of the most common types of sedimentary rock and is found in sedimentary basins throughout the world. Sandstone is a sedimentary rock mainly composed of Quartz or Feldspar. When metamorphosed Sandstone changes to Quartzite.
Decaying vegetation produces organic acids which causes a breakdown of minerals. This is ________
Over time, large enough cracks develop and weathering takes place. Plants, such as moss, are capable of releasing weak organic acids, that will dissolve minerals from the rocks and cause chemical weathering. Apart from moss, organisms such as fungus and lichen are also capable of similar chemical weathering action.