ABSTRACT The use of artificial intelligence (AI) and machine learning (ML) methods in the geosciences can be categorized into three types, those that: (1) accelerate computationally expensive Earth system models; (2) fill the vacuum where numerical and physics-based models struggle; and (3) enable and enlighten data-driven discoveries. To achieve these tasks, many cyberinfrastructure (CI) systems are required. This chapter reviews the cutting-edge CI aiding the implementation of AI in the geosciences. Each technique presented is evaluated to assist geoscientists in determining how appropriate it is. Use cases in the subdomains of seismology, hydrology, and climatology are introduced to help readers understand the workflows. Challenges and future opportunities for CI development center on big data, provenance, interoperability, and heterogeneity due to the scale and complexity that future AI models in the geosciences will require.

Abstract Any archaeological site, according to the Brazilian Federal Constitution, is a patrimony of the Union; consequently, when crimes against this cultural patrimony occur, it becomes the responsibility of the Federal Police of Brazil. In 2013, there was a complaint to the Brazilian Federal Public Prosecutor's Office about the depredation of an archaeological site and forced withdrawal of the indigenous people because of the construction of a multimodal port in the city of Guaíra, in the state of Paraná, in southern Brazil. Thus, the Technical–Scientific Sector of the Federal Police Department, in partnership with Brazilian universities, used standard geophysical methods such as ground-penetrating radar (GPR) to investigate and locate buried archaeological targets. This paper discusses the results of 2D and 3D investigations in the Tekoha Jevy indigenous village, located in Guaíra County. In the field, 32 parallel sections of GPR data were acquired using 250 and 700 MHz shielded antennas. The results showed several anomalies, two of which were subjected to field checks using excavations, which revealed several artefacts such as ceramic fragments associated with ancient indigenous occupations on the banks of the Paraná River.

ABSTRACT We defined the timing of surface abandonment for 10 alluvial and debris-flow fans across contrasting climatic settings in the NW Himalaya of northern India using cosmogenic 10 Be surface exposure dating. Debris-flow fans in the Garhwal, Kullu, and Lahul-Spiti regions of the monsoon-influenced Greater Himalaya were largely abandoned during the Mid- to Late Holocene. Large alluvial fans and smaller debris-flow fans in the semiarid Ladakh region of the Greater and Tethyan Himalaya have surface ages that extend throughout the last glacial. Regional events of landform abandonment and incision were defined for the monsoon-influenced western Himalaya ranges and the semiarid western Himalaya ranges over the past ~120 k.y. In the monsoon-influenced and semiarid western Himalaya ranges, these regional events were limited to the Holocene and from ca. 40 ka, respectively. The timing of fan surface abandonment and regional landform abandonment events coincided with periods of weakening monsoon strength and cooling, and local and regional glacier advances. Regional incision events from the monsoon-influenced and semiarid western Himalaya regions were recognized across various climatic conditions due to the ubiquitous nature of erosion in mountain settings. This study showed that climate-driven processes and glaciation were important drivers in fan sedimentation, catchment sediment flux, and the topographic evolution of the NW Himalaya during the late Quaternary.

ABSTRACT Uplift of the central Andes during the Miocene was followed by large-scale reorganization of Atlantic-draining rivers in Argentine Patagonia. Here, we document the abandonment of one large river in the late Pliocene and the establishment of the modern drainage in the Early Pleistocene. A chronology for these events is provided by 40 Ar/ 39 Ar ages on basalt flows. Remnants of the Pliocene paleovalley system are well preserved in the Lago Cardiel–Gobernador Gregores area, where they are eroded into flat-lying basalt flows dated from ca. 13.9 Ma to 8.6 Ma. Younger basalts that erupted onto the abandoned floor of the paleovalley are as young as 3.7 Ma. Abandonment of the Pliocene paleovalley and establishment of the modern Río Chico and Río Shehuen catchments happened near the close of the Pliocene when Andean glaciers incised the east-sloping pediment on which the late Miocene drainage was established. Lago Cardiel sits within a large endorheic basin that is inset into the late Pliocene paleovalley. The basin began to develop just before 4 Ma, after the paleovalley was abandoned. It became larger and deeper during the Pleistocene due to mass movements along its margins, deflation of the basin floor during times when Lago Cardiel was dry or nearly dry, and possibly lowering along bounding faults. The Pliocene–Pleistocene landscape and drainage changes that we have documented are not unique to the Lago Cardiel–Gobernador Gregores area; similar changes are apparent elsewhere in Patagonia east of the crest of the Andes.

ABSTRACT Glaciers in central Asia that developed under a range of climatic conditions from arid to humid provide an excellent opportunity to test glacial responses to changes in climate. To do this, we mapped and dated glacial deposits at 11 sites spread over five mountain ranges in central Asia: the Altai, Tian Shan, Altyn Tagh, Qilian Shan, and Kunlun. The glacial chronologies for these sites were determined from new 10 Be and 26 Al exposure ages for the mapped moraines, in addition to 10 Be ages available in the literature. Paleo–equilibrium-line altitudes were estimated for past glacier extents from the dated moraines. The equilibrium-line altitudes (ELAs) were also estimated for existing glaciers to characterize the spatial pattern in modern climate across the study region. Differences between the modern and paleo-ELAs (∆ELAs) were used to explore the climatic reasons for variations in the glacier sensitivities and responses to past changes in climate. The results show that the glaciers in more humid regions advanced to their maximum during marine oxygen-isotope stage (MIS) 3–2 with ΔELAs of ~1100–600 m. However, glaciers in the arid interior of central Asia, in the rain shadows of the Karakorum and Pamir ranges and in the Gobi Desert ranges, reached their maximum between MIS 6 and 4, and glacier extents during the subsequent colder/drier MIS 3–2 were significantly smaller or did not extend beyond their cirques. Comparisons of our results and the sensitivity analysis of modern glaciers suggest that depression of air temperature was the primary driver of glacier advances in central Asia but that precipitation played a major role in shaping the spatial and temporal heterogeneity of glacier advances. Precipitation was especially important in hyperarid conditions. Therefore, inferences about paleoclimate parameters from past glacial extents must be made after careful consideration of the climatic setting in which the glaciers are found, as well as their sensitivity to climatic factors.

ABSTRACT In this paper, we present a case study to demonstrate the potential of photogrammetry in cyclostratigraphic applications. To this end, we considered an ~300-m-thick section exposing the Lower Jurassic Calcare Massiccio Formation in the Marche Apennines of central Italy. The Calcare Massiccio comprises a thick succession of peritidal shallow-water carbonates displaying a prominent sedimentary cyclicity, where supratidal and subtidal facies alternate. The section investigated in this study is exposed on the wall of an active quarry and is almost completely inaccessible because it is vertical and because of safety and liability regulations. This setting prevents the application of standard sampling and facies analysis techniques on the whole series. An accurate three-dimensional model of the quarry wall was therefore produced by processing ~360 digital images through photogrammetry and generating a high-resolution (centimeter-scale) point cloud of the outcrop with red-green-blue (RGB) values associated with each point. An ~150-m-long log representing color variations on a continuous portion of the exposed succession was then extracted from the point cloud by converting the original RGB values to grayscale values. The main facies were directly investigated in an ~10-m-long accessible section that was logged and sampled, and it was established that supratidal facies with planar stromatolites and teepee structures are darker in color, while subtidal facies, made of bioturbated mudstones to floatstones with gastropods and oncoids, display lighter color. This provided ground-truth data with which to interpret the grayscale variations in terms of facies alternations. Time-series analysis was then carried out on the grayscale series, and this revealed prominent cyclicities. Because the biochronostratigraphic framework of the Calcare Massiccio is poor, the potential orbital origin of these frequencies was tested with the average spectral misfit technique. Preliminary results suggest that the observed spectral features are compatible with Milankovitch periods and that astronomical forcing might have been a major driver in the deposition of the Calcare Massiccio Formation. Furthermore, they testify to the great potential of photogrammetry in cyclostratigraphic applications, especially when large-scale, inaccessible outcrops have to be investigated.

Abstract In contrast with the archetypal definition of an alluvial fan, this study shows that fans interacting with axial rivers in Yukon and Alaska commonly exhibit asymmetrical morphology in planform. Hypothesis tests relating to the geomorphological characteristics of these alluvial fans were conducted on a dataset of 63 fluvial-dominated fans. A significant relationship existed between fan asymmetry and the direction of axial river flow, which was attributed to two factors supported by examples: (1) axial rivers have a propensity to trim the toes on the up-valley sides of fans; and (2) axial river channels are deflected across the broad valley floors, which allows the profiles on the down-valley sides of fans to be longer than on the up-valley sides. However, an asymmetrical planform morphology does not lead to a significant bias in the spatial distribution of surface streams towards the up-valley sides of fans, which typically have shorter profiles from apex to boundary. If the asymmetry in fan morphology is preserved in the sedimentary record, then the interpretation of fan deposits that developed in broad valleys and that interacted with axial rivers would be improved by understanding this modern analogue.