In this very first chapter, I would like to give you an idea of the term “crystal structure.” First of all, we want to get an impression of how large or small crystalline objects can be. For this purpose, take a look at . Fig. 1.1, which is based on the popular short film “Powers of Ten” from 1977 [1]. This short film illustrates in a beautiful way, of which sizes objects are that are subject of scientific investigations. They span an impressive range of orders of magnitude. We do not want to explain all objects in detail, but instead will focus on just a few. <...>

Two thousand million years (Ma) ago a mountain-sized bolide from Space, travelling at tens of thousands of kilometres per hour, slammed into the Earth at a position approximately 120 km southwest of the present-day city of Johannesburg, in the vicinity of the present towns of Vredefort and Parys. Within moments, it had blown a hole tens of kilometres deep and more than 100 km wide into the crust of the Earth. Th e force of the impact hurled countless millions of tonnes of rock, some of it heated to temperatures of thousands of degrees centigrade (°C), around the crater over an area extending for hundreds of kilometres from the impact site (Fig. 3a).

The fact that there was an Ice Age at all is a relatively recent discovery. It began when, at the meeting of the Swiss Natural History Society in Neuchâtel on July 24, 1837, the young president of the society, Louis Agassiz, surprisingly did not talk about the latest results of his investigations on fossil fshes, by which he had become famous. Instead, he declared that the erratic blocks in the Jura (and around Neuchâtel) were legacies of a great glaciation. It was to take many years before this concept was internationally recognized. <...>

The Istituto di Ricerca per la Protezione Idrogeologica (IRPI), of the Italian Consiglio Nazionale delle Ricerche (CNR), designs and executes research, technical and development activities in the vast and variegated field of natural hazards, vulnerability assessment and georisk mitigation. We study all geo-hydrological hazards, including floods, landslides, erosion processes, subsidence, droughts, and hazards in coastal and mountain areas. We investigate the availability and quality of water, the exploitation of geo-resources, and the disposal of wastes. We research the expected impact of climatic and environmental changes on geo-hazards and georesources, and we contribute to the design of sustainable adaptation strategies. Our outreach activities contribute to educate and inform on geo-hazards and their consequences in Italy. <...>

Earthquakes pose a significant threat to countries around the world. But, equipped with the right knowledge and tools, engineers and seismologists can support policy and decision-makers in creating a safer future for all of us. The Third European Conference on Earthquake Engineering and Seismology (3ECEES), jointly organized by Technical University of Civil Engineering of Bucharest (UTCB) and National Institute for Earth Physics (INFP) in Bucharest, Romania,

Volcanic eruptions have been one of the most fundamental influences on the Earth’s evolution throughout its 4.54 Ga history. Volcanic eruptions formed the Earth’s crust, were the source for the atmosphere and oceans and are arguably the basis for life on Earth. Huge eruptions have almost certainly caused climate change and influenced mass extinction events.

The Mw 7.1 (Mj 7.3) Kumamoto earthquake occurred on April 16, 2016, resulting in more than 100 deaths and extensive damage on Kyushu Island in southwestern Japan. In order to determine the motion of the seismogenic fault, ground deformation, and relationships between coseismic surface ruptures and pre-existing faults, our survey group conducted fieldworks immediately, beginning one day after the main shock.

The primary objective of this paper is to present a semiautomatic procedure that, integrated with traditional methods, can be useful for a rapid definition of rock fall susceptibility scenarios with the purpose of civil protection. Due to its morphology (steep slopes and narrow valleys), regional seismicity, and rock mass characteristics, the Nera Valley (Valnerina, Umbria Region, Italy) is characterized by high rock fall risk. With the aim of covering a wide range of features and investigating the main advantages and drawbacks of the proposed approach, data collection (terrestrial laser scanning (TLS) and geomechanical surveys) was carried out at three different slopes. Detailed threedimensional (3D) models were created to reconstruct the shape and volume of the most unstable blocks, to define the position of the main rock fall source areas, and to precisely distinguish the outcropping materials and the position of the elements at risk for reliable runout analyses. The proposed approach can be useful in supporting proper maintenance and land management programs both in ordinary and in emergency circumstances. <...>

The giant outer planets—Jupiter, Saturn, Uranus, and Neptune (Figure 1.1)—are by far the largest planetary bodies in the solar system and together comprise 99.56% of the planetary mass. Although very far from the Earth, the enormous physical size of Jupiter and Saturn meant that these planets were easily visible to the ancients. However, the other two “giants”, Uranus and Neptune, are significantly smaller and so much farther from the Earth that they were unknown before the advent of telescopes, although Uranus is in fact just visible to the naked eye. Uranus was discovered by accident in 1781 by William Herschel (1738-1822) (later Sir William Herschel). Perturbations in the observed orbit of Uranus led John Couch Adams (1819-1892) and Urbain Jean Joseph Le Verrier (1811-1877) to independently predict the presence of a further planet, and Neptune was subsequently discovered close to its predicted position by Johann Gottfried Galle (1812-1910) in 1846. The mean observable properties of the outer planets are listed in Table 1.1. <...>