Related Experiment Video
Updated: Mar 22, 2026
06:55
Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
8.6K
Impact structures in Africa: A review
Wolf Uwe Reimold1, Christian Koeberl2
1Museum für Naturkunde Berlin, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstrasse 43, 10115 Berlin, Germany; Humboldt Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany.
Journal of African Earth Sciences (Oxford, England : 1994)
|April 12, 2016
Summary
Impact cratering is a fundamental planetary process, crucial for Earth's geological and biological evolution. This review details Africa's impact record, highlighting confirmed structures and potential new discoveries.
Area of Science:
- Planetary Science
- Geology
- Impact Cratering Studies
Background:
- Impact cratering is a fundamental process in planetary evolution and has influenced life on Earth.
- The terrestrial impact record is incomplete, necessitating hands-on investigations beyond remote sensing.
- Understanding impact processes requires integrating field studies, shock experiments, and numerical modeling.
Approach:
- Reviewing the current status of impact cratering research.
- Providing a detailed account of the African impact record, updated since 1994.
- Analyzing confirmed impact structures, shatter cones, impact glasses, and tektites in Africa.
Key Points:
- Africa now has 19 confirmed impact structures and one shatter cone occurrence.
- 49 potential impact sites exist in Africa, with promise for future discoveries.
- 28 structures have been confirmed as non-impact in origin, underscoring research interest.
Conclusions:
- Impact cratering is essential for understanding Earth's geological and biological evolution.
- This review serves as a reference for identifying impact craters and ejecta in Africa.
- Further research in Africa is crucial for expanding the global impact record.
Related Concept Videos
01:18Indeterminate Structure
1.5K
Indeterminate structures refer to structures where internal forces and reactions cannot be determined using only the equations of static equilibrium. Indeterminate structures have more unknown forces and reaction forces than equations of static equilibrium that can be used to determine them. Indeterminate structures are often used in engineering to create complex, efficient, and aesthetically pleasing structures. There are various types of indeterminate structures used in engineering and...
1.5K
01:14Stability of structures
590
In mechanical engineering, the stability of systems under various forces is critical for designing durable and efficient structures. One fundamental way to explore these concepts is by analyzing systems like two rods connected at a pivot point, O, with a torsional spring of spring constant k at the pivot point. This system is similar in appearance to a scissor jack used to change tires on a car. In this case, the arms of the linkage (equivalent to the rods in this system) are entirely vertical,...
590
01:19Impact Loading
825
Impact loading occurs when a moving object collides with a stationary structure, such as a rod with a uniform cross-sectional area fixed at one end. Under these conditions, the rod absorbs the kinetic energy from the striking object, leading to deformation and subsequent stress development. As the rod returns to its original position and reaches maximum stress, the absorbed energy, initially manifested as kinetic energy, transforms entirely into strain energy.
In cases of elastic deformation,...
In cases of elastic deformation,...
825
01:30Types of Impact
1.1K
Impacts can be classified in various forms, primarily under two subgroups: central impact and oblique impact. A central impact occurs when two objects collide head-on, possessing opposite velocities aligned along the line of impact. Conversely, an oblique impact occurs when two objects collide at an angle, resulting in a modification of both direction and velocity.
The coefficient of restitution is a metric for understanding the dynamics of impacts. It quantifies the ratio of relative velocity...
The coefficient of restitution is a metric for understanding the dynamics of impacts. It quantifies the ratio of relative velocity...
1.1K
01:21Impact Strength of Concrete
694
Impact strength in concrete is a critical measure that reflects the material's capability to endure the forces applied during pile driving and when supporting machinery foundations that experience impulsive loads. It is also essential when handling precast concrete components to prevent accidental damage. The impact strength is assessed by observing the concrete's resistance to repeated impacts and energy absorption capacity. A key indicator of significant damage to concrete is when it...
694
01:25Effects of Creep
541
Creep in concrete, the gradual deformation under prolonged stress, significantly impacts the integrity of structures. For reinforced concrete beams, it can be a vital design consideration, as it increases deflection, sometimes necessitating additional design measures. In columns, especially slender ones under eccentric loads, creep can cause buckling, compromising their stability. However, creep can be beneficial in indeterminate structures by mitigating stresses that arise from shrinkage,...
541