Exploring Causal Relationships for Geoheritage Interpretation — Variable Effects of Cenozoic Volcanism in Central European Sedimentary Tablelands

Modern conceptual approach to geointerpretation and geoeducation emphasizes the holistic understanding of the environment and attends to linkages between various abiotic, biotic, and cultural components. In this paper, we highlight multiple relationships between Cenozoic volcanism and host sedimentary rocks, mainly sandstones of Cretaceous age, which can be explored in the context of geotourism and geoeducation in several Central European geoparks (Bohemian Paradise UNESCO Global Geopark, Land of Extinct Volcanoes Aspiring Geopark, Ralsko National Geopark) and their surroundings. These include the effects of magmatism on sandstones, with further consequences for landform development at different spatial scales, the origin of mineral resources, underpinning of biological diversity, and specific land use contrasts. Existing interpretation provisions are reviewed, and a three-tiered framework to show these different linkages is proposed. It is argued that different, but complementary themes can be addressed at the landscape, landform, and individual outcrop (geosite) level.

Rock properties and rock-controlled landforms

Rock properties are a crucial control of landform development. The purpose of this chapter is to examine the progress that was made in studying rock properties in general and then to discuss developments in the study of landforms in three main rock types: granite, limestone and sandstone. From the mid-1960s onwards, geomorphology witnessed an increasing concern with the quantification of rock properties and their relationship to landforms and landscape evolution. Japanese geomorphologists led in this endeavour. Studies crossed a range of scales from those of a large size, that were susceptible to field measurements, and those of small size that involved laboratory studies. Among the basic characteristics of rocks that have been studied are fracturing and jointing, rock mass strength, hardness as determined by the Schmidt Hammer, resistance as determined by laboratory simulations, slaking susceptibility, porosity, water absorption capacity, water content and permeability, and petrological thin section analyses. The investigation of forms and processes in granite, limestone and sandstone areas has shown the value of combined geological and geographical approaches, and the increasing internationalization of studies.

Contextualizing lobate debris aprons and glacier-like forms on Mars with debris-covered glaciers on Earth

Debris-covered glaciers from around the world offer distinct environmental, climatic, and historical conditions from which to study the effects of debris on glacier-ice evolution. A rich literature on debris-covered glaciers exists from decades of field work, laboratory studies, remote-sensing observations, and numerical modeling. In general, the base of knowledge established by studying periglacial, glacial, and paraglacial landforms on Earth has been applied to aid interpretation of ice-rich or ice-remnant landforms on Mars, but research has progressed on both planets. For Mars, the spatial distribution of lobate debris aprons and glacier-like forms, in particular, is critical to constraining past climate conditions when such features were active, reconstructing past ice extent, and estimating the total inventory of buried ice remaining in the mid-latitudes of Mars. This review spans a range of knowledge about debris-covered glaciers on Earth, in order to add context to investigations of dust and debris-covered ice on Mars and to put research on both planets in a perspective aimed at maximizing process-based understanding of glacier evolution. The state of knowledge and some gaps in knowledge on Mars are discussed in relation to possible avenues for future research in how landforms are classified, advances in comparative planetology, and new understanding from future missions. While this review is focused primarily on processes controlling active debris-covered glaciers, a key to understanding glacier change through time is to consider individual landforms in context with the full-system environment in which they are found. For Earth, this includes understanding local and regional controls on current glacier change, and how these processes relate to landform development in the past as well as what may develop in the future. For Mars, this includes evaluating how present-day landforms elucidate past ice activity and environmental conditions during epochs when orbital parameters, climate, and water ice distribution were substantially different.