This text is designed for use in advanced undergraduate or early graduate courses in igneous and metamorphic petrology. The book is extensive enough to be used in separate igneous and metamorphic courses, but I use it for a one-semester combined course by selecting from the available chapters. The nature of geological investi-gations has largely shaped the approach that I follow.

This book is the first in a two-volume series that introduces the field of spatial data science. It offers an accessible overview of the methodology of exploratory spatial data analysis. It also constitutes the definitive user’s guide for the widely adopted GeoDa open-source software for spatial analysis. Leveraging a large number of real-world empirical illustrations, readers will gain an understanding of the main concepts and techniques, using dynamic graphics for thematic mapping, statistical graphing, and, most centrally, the analysis of spatial autocorrelation. Key to this analysis is the concept of local indicators of spatial association, pioneered by the author and recently extended to the analysis of multivariate data.

Morphology

Diatoms are microscopic unicellular algae. Whatever the shape or size of the cell, it consists of the same basic parts: the nucleus, cytoplasm, plasma membrane, and the cell wall.

1.1. Structure of the Cell Wall

Emphasis in this Introduction is placed on the structure of the diatom cell wall, as opposed to the living contents, as, in the main, interest in diatom study is directed toward the structure and microstructure of the cell wall. Classification of diatoms and their identification pertinent to many areas of investigation is based on the structure of, and markings on the cell wall as revealed by the light microscope (LM). It is therefore imperative that the student of diatoms possesses a good basic knowledge of that structure and the terminology associated with it. <...>

As Earth' s crust is the most accessible part of our planet, a wealth of information on its structure and composition is available from geological observations and geophysical measurements. Its shape and composition today are, however, the result of processes occurring at different scales in time and space, rendering study of the crust a complex and challenging undertaking. Field observations and seismic data, for example, confront us with the present day structures and must, for an in-depth understanding of their origin, be reconciled with the processes of deformation that created them. Reconstructing these processes in the past is commonly hindered by lack of continuous outcrop, limited depth resolution and little to no constraints on time. Analogue and numerical models may help improve our understanding of crustal-scale processes through their ability to simulate the birth and evolution of deformational structures at different scales. In this context, the link between theory and observations makes modelling a fundamental tool for the study of processes that alter the Earth's crust. <...>