Are there rift valleys on mars

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Landforms are natural and distinctive features. Explore how they show up in various landscapes. These resources can be used to teach middle schoolers more about the natural world, its distinctive features, and landscapes. These tectonic plates rest upon the convecting mantle, which causes them to move.

The movements of these plates can account for noticeable geologic events such as earthquakes, volcanic eruptions, and more subtle yet sublime events, like the building of mountains. Teach your students about plate tectonics using these classroom resources.

Weathering is the process of the weakening and breakdown of rocks, metals, and manmade objects. There are two main types of weathering: chemical and physical.

An example of chemical weathering is acid rain. Caused mostly by the burning of fossil fuels, acid rain is a form of precipitation with high levels of sulfuric acid, which can cause erosion in the materials in which it comes in contact. An example of physical weathering is wind blowing across the desert playas. This process causes rocks to form a specific pyramid-like shape and they are called ventifacts. Select from these resources to teach about the process of weathering in your classroom.

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Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary. Rift valleys are found both on land and at the bottom of the ocean, where they are created by the process of seafloor spreading. Rift valleys differ from river valley s and glacial valley s in that they are created by tectonic activity and not the process of erosion. Tectonic plate s are huge, rocky slabs of Earth's lithosphere —its crust and upper mantle. Tectonic plates are constantly in motion—shifting against each other in fault zones, falling beneath one another in a process called subduction , crashing against one another at convergent plate boundaries, and tearing apart from each other at divergent plate boundaries.

Two arms of the triple junction can split to form an entire ocean. The Atlantic Ocean, for instance, is a result of a triple junction that started in what is now the Gulf of Guinea on the west coast of Africa. From the east end of Valles Marineris, the water flowed through a sequence of channels before reaching the Chryse basin. Northwest of Valles Marineris, a similar flood emerged from a depression called Echus Chasma to form the Kasei Valles outflow channel.

A mystery remains whether these floods were single, overwhelming events in each channel - or a number of separate floods operating on lesser scales. The best evidence suggests the floods occurred in several stages, with at least one large outburst. The activity occurred over millions of years, but the episodes of flooding fall mainly within one period of martian history called the Hesperian.

This was a transition time that followed the period of heaviest cratering and greatest volcanic activity, the Noachian. It comes before the "modern era," the Amazonian. The Hesperian's timespan is known only roughly, but is thought to extend from about 3. During this time, besides the massive flooding and the growth of Tharsis, Mars experienced a slowing rate of impacts making craters and basins, and the climate shifted to colder and drier conditions.

Weakening Resistance. Not all the erosion within the valley produced catastrophic floods. In places such as Louros Valles, where numerous tributary canyons cut into the valley's southern rim, canyon widening and erosion occurred on smaller scales. These canyons likely formed by the same method as the main valley segments - release of groundwater - but the quantity of water was less, the scale was smaller, and the results more localized. As geologists reconstruct it, water emerged from the canyon walls as springs and seeps and carried away sediment.

In its wake, this sapping process left round-headed valleys that slowly retreated from the rim of the canyon. As faults and cracks in the rock guided the sapping, the growing valleys developed a characteristic tree-branch shape. It's worth comparing the tributary canyon seen here to the Grand Canyon in northern Arizona. The Grand Canyon is about kilometers miles long, while this tributary is only kilometers 72 miles long.

But where this valley empties into Valles Marineris, it is more than 3, meters 12, feet deep - over twice the depth of Earth's Grand Canyon. Groundwater's effects can be seen also with the crater at bottom center. About 7 km 4. Scientists call this a rampart crater, and they believe the skirt shows the ground held a lot of water or ice at the time of impact. The heat of the blast released the water and lubricated the flying debris, producing a semi-solid splash pattern edged by the rampart, which is about 70 meters feet high.

Making Landfall. Undermined cliffs and valley walls are usually unstable, and Valles Marineris has grown wider in many places through landslides. This particular slide dropped thousands of feet and has a maximum length of about kilometers 60 miles.

A closer look at it shows that several landslides have occurred here, with each now slide lying on top of the previous ones.

As examples on Earth show, landslides can travel great distances, especially when the debris contains trapped water or air to lower friction. Scientists think it likely that even the thin air of Mars would have contributed to this slide's remarkable run. Similar, if shorter, landslides lie throughout most of Valles Marineris, and helped to widen the canyon as it developed. The vast canyon can be seen from Earth through a telescope as a dark scarring on the planet's surface.

Features known as chasmata , steep depressions that resemble canyons on Earth, dominate the canyon. The canyon begins in the Noctis Labyrinthus on the western edge, a region of material thought to have volcanic origins. Two parallel chasmata, Ius and Tithonium, stretch eastward, and contain lava flows and faults from the Tharsis Bulge.

Three more chasmata, Melas , Candor and Ophir, are connected on the east side of the parallel features. Their floors contain eroded material and volcanic ash. The floor of the Melas chasma contains the deepest point of the canyon system.

Coprates Chasma lies farther east, with well-defined layered deposits. These deposits may have formed from landslides or wind-blown material, although the region may once have housed isolated lakes. This canyon, one of the lowest points in Valles Marineris, boasts a handful of its own volcanoes, though they are small compared to Olympus Mons , the largest volcano in the solar system, and its neighbors.

The meter high cones were only recently identified. This is surprising, given that the bulk of Martian volcanism took place around 3.

Eos and Ganges are another set of chasmata that contain volcanic or windblown deposits that have slowly eroded over time. The Valles Marineris system empties into the Chryse region, one of the lowest regions on Mars. Any water from the canyon system would have flown into the lowlands, and it may have once contained an ancient lake or ocean.

Over the years, scientists have proposed a number of theories about the formation of Valles Marineris. Erosion during a water-rich past and the withdrawal of subsurface magma were both early possibilities. Today, most scientists think that the formation of the Tharsis region may have helped the canyon to form.