• Stability of steady frictional sliding, inertia and the quasi-static limit • work on ps 4; see course web site

The Mechanics Of Earthquakes And Faulting

The World Stress Map database release 2016 : Crustal stress pattern across scales

Fundamentals of Rock Mechanics

Global review of human-induced earthquakes

Earth System Models (ESMs) are essential tools for understanding and predicting global change, but they cannot explicitly resolve hillslope‐scale terrain structures that fundamentally organize water, energy, and biogeochemical stores and fluxes at subgrid scales. Here we bring together hydrologists, Critical Zone scientists, and ESM developers, to explore how hillslope structures may modulate ESM grid‐level water, energy, and biogeochemical fluxes. In contrast to the one‐dimensional (1‐D), 2‐ to 3‐m deep, and free‐draining soil hydrology in most ESM land models, we hypothesize that 3‐D, lateral ridge‐to‐valley flow through shallow and deep paths and insolation contrasts between sunny and shady slopes are the top two globally quantifiable organizers of water and energy (and vegetation) within an ESM grid cell. We hypothesize that these two processes are likely to impact ESM predictions where (and when) water and/or energy are limiting. We further hypothesize that, if implemented in ESM land models, these processes will increase simulated continental water storage and residence time, buffering terrestrial ecosystems against seasonal and interannual droughts. We explore efficient ways to capture these mechanisms in ESMs and identify critical knowledge gaps preventing us from scaling up hillslope to global processes. One such gap is our extremely limited knowledge of the subsurface, where water is stored (supporting vegetation) and released to stream baseflow (supporting aquatic ecosystems). We conclude with a set of organizing hypotheses and a call for global syntheses activities and model experiments to assess the impact of hillslope hydrology on global change predictions.

/pdf/hillslope-hydrology-in-global-change-research-and-earth-3lzqeyyael.pdf

Hillslope Hydrology in Global Change Research and Earth System Modeling

World Stress Map Database Release 2016

World Stress Map 2016

A revised crustal stress orientation database for Canada

Threats posed by the climate crisis have created an urgent need for sustainable green energy. Geothermal resources have the potential to provide up to 150 GWe of sustainable energy by 2050. However, the key challenge in successfully locating and drilling geothermal wells is to understand how the heterogeneous structure of the subsurface controls the existence of exploitable fluid reservoirs. In this Review, we discuss how key geological factors contribute to the profitable utilization of intermediate-temperature to high-temperature geothermal resources for power generation. The main driver of geothermal activity is elevated crustal heat flow, which is focused in regions of active magmatism and/or crustal thinning. Permeable structures such as faults exercise a primary control on local fluid flow patterns, with most upflow zones residing in complex fault interaction zones. Major risks in geothermal resource assessment and operation include locating sufficient permeability for fluid extraction, in addition to declining reservoir pressure and the potential of induced seismicity. Advanced computational methods permit effective integration of multiple datasets and, thus, can reduce potential risks. Future innovations involve engineered geothermal systems as well as supercritical and offshore geothermal resources, which could greatly expand the global application of geothermal energy but require detailed knowledge of the respective geological conditions. Successful discovery and operation of geothermal resources requires a thorough understanding of the heterogeneous geological subsurface. This Review discusses the key geological factors that contribute to the effective exploration of intermediate-temperature to high-temperature geothermal resources used for power generation and direct use applications.

Moritz Ziegler

Papers

The World Stress Map database release 2016 : Crustal stress pattern across scales

World Stress Map Database Release 2016

World Stress Map 2016

A revised crustal stress orientation database for Canada

Geological controls on geothermal resources for power generation