Jasper Seamount
Encyclopedia
Jasper Seamount is a seamount
(underwater volcano) located in the Fieberling-Guadalupe seamount track, west of Baja California
, Mexico
. Jasper is the site of detailed geophysical
geological
and geochemical
studies which suggest that many seamounts, big and small, follow the same pattern of growth and death that was originally used to describe the Hawaiian - Emperor seamount chain.
Jasper Seamount is an elongated volcano, with a northwest-northeast summit and several volcanic cone
s on the summit. A total of 15 dredge hauls from the seamount have been collected, and ocean-bottom seismometer
s have been placed to observe earthquake activity. In-depth studies have given scientists a detailed view of the seamount's internal structure.
The model developed by the Jasper Seamount studies closely resembles that of the Hawaiian islands
, especially the eruption, in stages, of increasingly alkalic rocks. More than 90% of the volcano is tholeiitic to alkalic basalt
in a wide variety of forms, including pillow lava
and vesicular
lapilli
, evidence of shallow submarine eruptions in the past, and a wide range of xenolith
s.
Jasper Seamount formed years ago. Base volcanics are very similar to those found at Hawaii. The flanks formed about years ago, and its summit years ago. The maintenance of a near-constant silicon dioxide
ratio in all of the rocks collected is a sign of increasingly lower degrees of mantle melting
. Overall Jasper Seamount rock is very similar, even in trace element
s, to Hawaiian volcanics, despite Jasper's much smaller size (690 km³ (166 cu mi) versus ~3000 km³ (720 cu mi)). These results seem to show that the Hawaiian model
could be applied to other seamounts as well, and that many seamounts go through the same processes regardless of their size.
Seamount
A seamount is a mountain rising from the ocean seafloor that does not reach to the water's surface , and thus is not an island. These are typically formed from extinct volcanoes, that rise abruptly and are usually found rising from a seafloor of depth. They are defined by oceanographers as...
(underwater volcano) located in the Fieberling-Guadalupe seamount track, west of Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
, Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. Jasper is the site of detailed geophysical
Geophysics
Geophysics is the physics of the Earth and its environment in space; also the study of the Earth using quantitative physical methods. The term geophysics sometimes refers only to the geological applications: Earth's shape; its gravitational and magnetic fields; its internal structure and...
geological
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
and geochemical
Geochemistry
The field of geochemistry involves study of the chemical composition of the Earth and other planets, chemical processes and reactions that govern the composition of rocks, water, and soils, and the cycles of matter and energy that transport the Earth's chemical components in time and space, and...
studies which suggest that many seamounts, big and small, follow the same pattern of growth and death that was originally used to describe the Hawaiian - Emperor seamount chain.
Jasper Seamount is an elongated volcano, with a northwest-northeast summit and several volcanic cone
Volcanic cone
Volcanic cones are among the simplest volcanic formations. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption...
s on the summit. A total of 15 dredge hauls from the seamount have been collected, and ocean-bottom seismometer
Seismometer
Seismometers are instruments that measure motions of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions, and other seismic sources...
s have been placed to observe earthquake activity. In-depth studies have given scientists a detailed view of the seamount's internal structure.
The model developed by the Jasper Seamount studies closely resembles that of the Hawaiian islands
Hawaiian Islands
The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...
, especially the eruption, in stages, of increasingly alkalic rocks. More than 90% of the volcano is tholeiitic to alkalic basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
in a wide variety of forms, including pillow lava
Pillow lava
Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava under water, or subaqueous extrusion. Pillow lavas in volcanic rock are characterized by thick sequences of discontinuous pillow-shaped masses, commonly up to one metre in...
and vesicular
Vesicular texture
Vesicular texture is a volcanic rock texture characterised by a rock being pitted with many cavities at its surface and inside. The texture is often found in extrusive aphanitic, or glassy, igneous rock...
lapilli
Lapilli
Lapilli is a size classification term for tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. Lapilli means "little stones" in Latin. They are in some senses similar to ooids or pisoids in calcareous sediments.By definition lapilli range...
, evidence of shallow submarine eruptions in the past, and a wide range of xenolith
Xenolith
A xenolith is a rock fragment which becomes enveloped in a larger rock during the latter's development and hardening. In geology, the term xenolith is almost exclusively used to describe inclusions in igneous rock during magma emplacement and eruption...
s.
Jasper Seamount formed years ago. Base volcanics are very similar to those found at Hawaii. The flanks formed about years ago, and its summit years ago. The maintenance of a near-constant silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...
ratio in all of the rocks collected is a sign of increasingly lower degrees of mantle melting
Mantle (geology)
The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiation by density. The interior of the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a highly viscous layer between the crust and the outer core....
. Overall Jasper Seamount rock is very similar, even in trace element
Trace element
In analytical chemistry, a trace element is an element in a sample that has an average concentration of less than 100 parts per million measured in atomic count, or less than 100 micrograms per gram....
s, to Hawaiian volcanics, despite Jasper's much smaller size (690 km³ (166 cu mi) versus ~3000 km³ (720 cu mi)). These results seem to show that the Hawaiian model
Evolution of Hawaiian volcanoes
The fifteen volcanoes that make up the eight principal islands of Hawaii are the youngest in a chain of more than 129 volcanoes that stretch across the North Pacific Ocean, called the Hawaiian-Emperor seamount chain....
could be applied to other seamounts as well, and that many seamounts go through the same processes regardless of their size.
See also
- Graveyard SeamountsGraveyard SeamountsThe Graveyard Seamounts are a series of 28 small seamounts and ediffices located on the Chatham Rise, east of New Zealand. They cover about , and stand out from the surrounding oceanic plateau that measures several hundred kilometers...
- Mud volcanoMud volcanoThe term mud volcano or mud dome are used to refer to formations created by geo-excreted liquids and gases, although there are several different processes which may cause such activity. Hot water mixes with mud and surface deposits. Mud volcanoes are associated with subduction zones and about 700...
- Muirfield SeamountMuirfield SeamountThe Muirfield Seamount is a submarine mountain located in the Indian Ocean approximately 130 kilometres southwest of the Cocos Islands. The Cocos Islands are an Australian territory, and therefore the Muirfield Seamount is within in Australia's Exclusive Economic Zone...
- Sedlo SeamountSedlo SeamountSedlo Seamount is an isolated seamount and underwater volcano located in the Northeast Atlantic, northeast of Graciosa Island. It has an elongate structure, roughly . The summit is flat with three peaks. Sedlo Seamount sits on the ocean floor deep, and rises to within of the surface...
- South Chamorro SeamountSouth Chamorro SeamountSouth Chamorro Seamount is a large serpentinite mud volcano and seamount located in the Izu-Bonin-Mariana Arc, one of 16 such volcanoes in the arc. These seamounts are at their largest in diameter and in height...