Adriana Ocampo has led six research expeditions to study what geological formation that is more than 180 km in diameter and 20 km in depth
Chicxulub crater The Chicxulub crater ( ; ] ) is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is located near the town of Chicxulub, after which the crater is named. It was formed by a large asteroid or comet about 10 to 15 kilometres (6 to 9 miles) in diameter, the Chicxulub impactor, striking the Earth. The date of the impact coincides precisely with the Cretaceous–Paleogene boundary (K–Pg boundary), slightly less than 66 million years ago, and a widely accepted theory is that worldwide climate disruption from the event was the cause of the Cretaceous–Paleogene extinction event, a mass extinction in which 75% of plant and animal species on Earth suddenly became extinct, including all non-avian dinosaurs. The crater is more than 180 km in diameter and 20 km in depth, well into the continental crust of the region of about 10–30 km depth. It makes the feature the third of the largest confirmed impact structures on Earth.
Surface features of Venus The surface of Venus is dominated by geologic features that include volcanoes, large impact craters, and aeolian erosion and sedimentation landforms. Venus has a topography reflecting its single, strong crustal plate, with a unimodal elevation distribution (over 90% of the surface lies within an elevation of -1.0 and 2.5 km) that preserves geologic structures for long periods of time. Studies of the Venusian surface are based on imaging, radar, and altimetry data collected from several exploratory space probes, particularly "Magellan", since 1961 (see Venus Exploration). Despite its similarities to Earth in size, mass, density, and possibly composition, Venus has a unique geology that is unlike Earth's. Although much older than Earth's, the surface of Venus is relatively young compared to other terrestrial planets (<500 million years old), possibly due to a global-scale resurfacing event that buried much of the previous rock record. Venus is believed to have approximately the same bulk elemental composition as Earth, due to the physical similarities, but the exact composition is unknown. The surface conditions on Venus are more extreme than on Earth, with temperatures ranging from 453 to 473 °C and pressures of 95 bar. Venus lacks water, which makes crustal rock stronger and helps preserve surface features. The features observed provide evidence for the geological processes at work. Twenty feature types have been categorized thus far. These classes include local features, such as craters, coronae, and undae, as well as regional-scale features, such as planitiae, plana, and tesserae.