Describe any three characters of Himalya
Answers
Explanation:
is still active. As the bedrock is lifted, considerable stream erosion and gigantic landslides occur.
The Himalayan ranges can be grouped into four parallel longitudinal mountain belts of varying width, each having distinct physiographic features and its own geologic history. They are designated, from south to north, as the Outer, or Sub-, Himalayas (also called the Siwalik Range); the Lesser, or Lower, Himalayas; the Great Himalaya Range (Great Himalayas); and the Tethys, or Tibetan, Himalayas. Farther north lie the Trans-Himalayas in Tibet proper. From west to east the Himalayas are divided broadly into three mountainous regions: western, central, and eastern.
Geologic history
Over the past 65 million years, powerful global plate-tectonic forces have moved the Earth’s crust to form the band of Eurasian mountain ranges—including the Himalayas—that stretch from the Alps to the mountains of Southeast Asia.
Simplified north–south cross section of the Himalayas, revealing a foreland basin (Ganga Basin), an overthrusting of crystalline terrains onto the Indian Plate, and a steeper thrust fault (a ramp) beneath the Great Himalayas.
Simplified north–south cross section of the Himalayas, revealing a foreland basin (Ganga Basin), an overthrusting of crystalline terrains onto the Indian Plate, and a steeper thrust fault (a ramp) beneath the Great Himalayas.
Encyclopædia Britannica, Inc.
During the Jurassic Period (about 201 to 145 million years ago), a deep crustal downwarp—the Tethys Ocean—bordered the entire southern fringe of Eurasia, then excluding the Arabian Peninsula and the Indian subcontinent. About 180 million years ago, the old supercontinent of Gondwana (or Gondwanaland) began to break up. One of Gondwana’s fragments, the lithospheric plate that included the Indian subcontinent, pursued a northward collision course toward the Eurasian Plate during the ensuing 130 to 140 million years. The Indian-Australian Plate gradually confined the Tethys trench within a giant pincer between itself and the Eurasian Plate. As the Tethys trench narrowed, increasing compressive forces bent the layers of rock beneath it and created interlacing faults in its marine sediments. Masses of granites and basalts intruded from the depth of the mantle into that weakened sedimentary crust. Between about 40 and 50 million years ago, the Indian subcontinent finally collided with Eurasia. The plate containing India was sheared downward, or subducted, beneath the Tethys trench at an ever-increasing pitch.