Pitfalls of multiplied 3D landforms projection: mapping deep multilevel cave systems in the Alps (Gamssteig Cave System, Göll Massif)

The expedition investigated 2500 km of rugged limestone country in the West Sepik province of Papua New Guinea, between the Strickland Gorge and the Irian Jaya border. The main objectives were the location and mapping of caves in the high altitude karst of the Hindenburg mountains and the study of their biology, hydrology and structure. Two hundred systems were recorded and some were of vast dimensions. One open pit was 280 m deep and descents were made into other shaft systems for 340 m and 360 m. The longest cave located was Selminum Tem, in which 20-5 km of passages were surveyed and the fossil skeleton of a Miocene syrenian was discovered. Three appendices report briefly on the geomorphology, biology and anthropology of the area.

<p>Remote sensing technology based on laser scanning (LiDAR) has found a wide range of applications in cave mapping for a high degree of accuracy, level of detail, and time efficiency of this method. Besides the multidisciplinary research, the acquired data representing the cave morphology in a form of a dense point cloud became an essential part of the exploration for understanding the cave speleogenesis alongside capturing the current state that is of great importance in natural and cultural heritage documentation. Traditional cave cartography can benefit from using the LiDAR point clouds by a highly detailed 3D cave model enabling the creation of contours, shaded relief, or geomorphometric parameters, and a practically unlimited number of cross-sections. Compared to the passive remote sensing methods, such as photogrammetry, limited by the light conditions and cave dimensions, laser scanning is an active light-independent method that records additional attributes for each captured point in addition to its 3D coordinates. The recorded intensity of the backscattered laser pulse is very applicable for mapping purposes as it reveals spectral properties of the surface material bringing new aspects not only for the point cloud visualization but also for material differentiation, identification, and spatial localization of the cave paintings. The presented study introduces innovation in the methodology of creating a high-detail cave map from the acquired LiDAR data by combining derived cave floor model and semi-automatic procedure for identification of surface type based on the geomorphometric analysis and recorded intensity. The main benefit of the proposed approach is in the reduction of the author´s subjectivity and cave geometry generalization. By further automatization of this process, maps for large cave systems can be produced in a high level of detail.</p>

Chapter 93 - The Omega Cave System

Mapping and modelling the complicated geometry of caves is a challenging task that has traditionally been undertaken by tacheometric surveying methods. These methods are excellent for capturing the general shape of a cave system but they are not suitable for high-speed, high-resolution mapping of complex surfaces found in this environment. Terrestrial laser scanning (TLS) technologies can acquire millions of points represented by 3-D coordinates, at very high spatial densities on complex multifaceted surfaces within minutes. In the last few years, advances in measurement speed, reduction in size / cost and increased portability of this technology has revolutionised the collection of 3-D data. This paper discusses the methodological framework and the advantages / disadvantages of adopting terrestrial laser scanning to rapidly map a complex cave system on the example of the Domica Cave in Slovakia. This cave originated in the largest karst region in the West Carpathians. The collected data set or ‘point cloud’ contains over 11.9 billion measured points, captured in 5 days from 327 individual scanning positions. The dataset represents almost 1600 m of the cave passages. Semi-automatic registration of these scans was carried out using reference spheres placed in each scene and this method archived an overall registration error of 2.24 mm (RMSE). Transformation of the final registered point cloud from its local coordinate system to the national cartographic system was achieved with total accuracy of 21 mm (RMSE). This very detailed data set was used to create a 3-D cave surface model needed for volumetric analyses. In the future, it will be used for spatial analyses or simulating the interaction of surface and subsurface processes contributing to the development of the cave system on the basis of a 3-D GIS platform.

The Totes Gebirge is not only the largest karst massif in the Northern Calcareous Alps, it also contains the most cave passages. In this area we are investigating the vertical distribution of phreatic cave passages to determine cave levels. These are vertical zones with clusters of cave passages that can be correlated with former valley floors. Since only phreatic cave passages (i.e. caves that were permanently or episodically filled with water during their formation) are to be analysed, a genetic classification is made on the basis of field observations, cave maps, 3D surveys and descriptions. As of Sept. 2023, the Totes Gebirge range, including the adjacent Warscheneck and the Hohe Schrott, contains 3172 known caves with a total length of 821 km, including the two longest cave systems in Austria, the Schönberg- (156 km) and the Schwarzmooskogel-Höhlensystem (137 km). As small caves do not contribute significantly to these statistics, only caves ≥50 m were included. The remaining 754 caves have a total length of 790 km. Only 46 % of these caves are at least partially of phreatic origin, but they contain 92 % of the total passage length. After subtracting the caves from which no data were available and cave sections that are not phreatic in origin (i.e. vadose or those created by weathering and erosion), 641 km of cave sections remained, which were analysed for their vertical distribution in 25 m increments. The histogram of cave length distribution vs. elevation for the Totes Gebirge range shows only a single significant cluster of phreatic cave sections between 1300 and 1850 m above see level (a.s.l.), with a clear maximum at 1500 m. The massif was divided into four sub-regions and all of them show this main interval, which is why it was interpreted as a cave level. It correlates well with the Giant Cave Level known from all other karst massifs in the Northern Calcareous Alps analysed so far. However, it is peculiar that in the other massifs at least three cave levels are present. Other reasons, such as the lack of known caves and the large size of the massif, which could lead to overlapping of cave levels, are unlikely. Therefore, it seems possible that the palaeo surface drainage pattern around the Totes Gebirge or its uplift history was different from the other karst massifs in the Northern Calcareous Alps and that low-lying cave levels (Spring and Berger Cave Level) or an elevated one (Ruin Cave Level) did not develop. For each of the 21 largest cave systems (≥5 km in length), the peak of the vertical distribution of the phreatic passages was determined. Vectors were calculated in order to test whether palaeo-flow directions could be inferred from their distribution. These phreatic maxima indicate a general dip from ESE to WNW, which could be interpreted either as a palaeo-drainage direction or as a tectonic tilting of the whole massif after the formation of the passages.

In the context of teaching geomorphology phenomena, producing illustrations and animations can be a tedious process. We propose an experimental framework, dedicated to 3D erosion and sedimentation modeling written in C++, combined with an existing topological modeler. Using the ''generalized maps'' as the underlying 3D model, we process each case of collision between elements in the scene in order to guarantee both topological and geometrical coherence during user-defined animations. Erosion and sedimentation operations can be combined to manipulate evolution scenarios leading for example to the creation of arches, bridges, tunnels or caves. Some of these scenarios, implemented in our framework with the help of a geology teacher, are presented in this paper in order to show the technical feasibility of our project before developing new ones.

The Rising Star cave system in South Africa is best known as the discovery site of the hominin species Homo naledi . Situated within the Cradle of Humankind UNESCO World Heritage Site, the cave system comprises more than 2 km of passages, including at least two chambers with hominin fossil remains. Homo naledi presents a mosaic morphology sharing features with species within both Homo and Australopithecus . Its relationship with other species of Homo is not clear; it may be among the earliest branches of the genus, or it may be a sister species of modern and archaic humans. The date of the Dinaledi Chamber hominin fossils has been estimated between 236,000 and 335,000 years ago.

Iron age to medieval entomogamous vegetation and Rhinolophus hipposideros roost in South-Eastern Wales (UK)

Toca da Boa Vista and Toca da Barriguda (TBV-TBR) are two of the longest caves in South America and, although not physically connected, share a common origin and evolution. Together, they comprise over 145 km of passages that are mostly developed in five lithological units in a Precambrian dolomite host rock. The now relict caves display a mixed ramiform/spongework/network pattern that shows clear hypogene morphology. The inception of speleogenesis cannot be precisely determined but likely occurred several tens (if not hundreds) of millions of years ago, placing this system among the oldest caves in the world. The TBV-TBR system is controlled by a NE–SW-oriented fracture corridor; passages follow anticlines and troughs, showing morphological variations depending on the vertical position in relation to the carbonate units. The cave system is represented by a laterally extensive maze controlled by a highly fractured unit in which ascending flow was restricted by an upper less fractured unit (hydraulic seal). The long evolutionary history of the cave left numerous imprints, including widespread and remarkable condensation-corrosion processes that dissolved the bedrock and speleothems, abundant chemical and clastic sedimentation phases and flooded lower passages. Following the interception of the cave by surface denudation, a remarkably rich late Quaternary vertebrate fossil assemblage accumulated.

round-Water Basin Catchment Delineation by Dye Tracing, Water Table Mapping, Cave Mapping, and Geophysical Techniques: Bowling Green, Kentucky

This paper focuses on mission planning and cooperative navigation algorithms for multi-drone systems aimed at LiDAR-based mapping. It aims at demonstrating how multi-UAV cooperation can be used to fulfill LiDAR data georeferencing accuracy requirements, as well as to improve data collection capabilities, e.g., increasing coverage per unit time and point cloud density. These goals are achieved by exploiting the CDGNSS/Vision paradigm and properly defining the formation geometry and the UAV trajectories. The paper provides analytical tools to estimate point density considering different types of scanning LIDAR and to define attitude/pointing requirements. These tools are then used to support centralized cooperation-aware mission planning aimed at complete coverage for different target geometries. The validity of the proposed framework is demonstrated through numerical simulations considering a formation of three vehicles tasked with a powerline inspection mission. The results show that cooperative navigation allows for the reduction of angular and positioning estimation uncertainties, which results in a georeferencing error reduction of an order of magnitude and equal to 16.7 cm in the considered case.

Abstract. Caves are an inherently challenging environment for the collection of 3D data. Low-light, complex morphology, and often remote access contribute to the need for more integrated and portable systems for 3D documentation of archaeological and paleontological features. As part of the initial stages of the Human and Faunal Access Project, based in Quintana Roo, Mexico, our team completed documentation of cave entrances utilizing the Looq Integrated Multi-Camera Photogrammetry system for the purpose of providing accurate models of cave entrances. The now-submerged cave systems hold a myriad of evidence for Late Pleistocene and Early Holocene human and faunal interaction during a time when lower sea levels made the caves dry and accessible. The nearest entrances to known archaeological and paleontological features are important for understanding access, and the photogrammetric data will be combined with existing surface mobile LiDAR and traditional 2D cave mapping data as well as underwater photogrammetry and mapping data for the rest of the cave system. This paper serves to present the findings and methods used in incorporating the Looq system into our multi-modal data collection strategy alongside preliminary results for simulating both human and faunal access.

14.4 The Modern Geomorphological Map

The Akçakale cave is a significant natural and cultural heritage site in the Black Sea region of eastern Turkey. The complex geometry and difficult-to-access areas of the cave have made the use of traditional mapping methods challenging. To overcome these limitations, this study utilized TLS and UAV technology to produce highly accurate 2D and 3D data for cave management and risk assessment purposes. The TLS system was used to create a detailed 3D point cloud of the cave interior, while the UAV system generated a 3D model of the surface topography outside the cave. The two sets of data were combined in the GIS environment using a geodetic network established in the study area, providing a common geodetic reference system for both TLS and UAV data. The study found that the cave area is 13,750 m2, which is smaller than the area of 18,000 m2 that was previously estimated using conventional measurement methods. The volume and ceiling heights of the cave were calculated using the elevation models generated from TLS point cloud data. The 3D point cloud data were also used to map dripstone locations on the floor and ceiling of the cave, and the boundaries of rock blocks on the ground were precisely determined. The study identified potential risks associated with the cave, particularly the risk of rockfall in the source rock areas around the cave entrance and the southern part of the cave. The nearest building to the cave is approximately 35 meters away, and all the buildings in the area are less than 300 meters from the cave. In the event of the cave collapse, the buildings in the southern part of the cave are at risk of rockfall. This study demonstrates the effectiveness of combining data from TLS and UAV systems to generate broad and sensitive cave mapping and risk assessment data, which are critical for cave management and safety. The collected data can be used for cave stability investigations and rockfall risk assessments. This study provides a foundation for future explorations of the Akcakale cave and highlights the potential for modern surveying techniques to enhance our understanding of complex geological structures such as caves.

Geologic mapping provides many types of information essential both in exploration for new mineral deposits and during subsequent mining. Geologic mapping of outcrops is used to describe the primary lithology and morphology of rock bodies as well as age relationships between rock units. This information allows delineation of ore-bearing host rocks and postore rocks that obscure or truncate ores. Mapping gathers structural information, including attitudes of veins and postore faults that can be used to predict the geology in the subsurface or laterally under postore rocks, and improves the utility of geophysical data for refinement of subsurface targets. Mapping of the mineralogy of hydrothermal alteration zones, ore minerals, igneous rocks hosting ores, and oxidized and leached rocks that commonly occur at the surface above sulfide-bearing ores can be used in conjunction with geochemical data to produce zonation patterns to target potential ore or to define prospective corridors of exotic mineralization. Similarly, regional geologic mapping in regions with both Paleozoic-Mesozoic overthrusts and Cenozoic normal faults such as the Paleozoic and Mesozoic thrust belt of the United States Cordillera and Basin and Range Province can define prospective windows into basement where mineralization such as Carlin-type gold deposits may occur. In general, geologic mapping underpins the construction of three-dimensional geologic models or hypotheses that guide exploration and discovery and, when geologic time is considered, produces the fourdimensional space-time models necessary for understanding of primary ore formation processes and postdepositional modification by secondary surficial and tectonic processes. Geologic mapping has been used extensively for exploration for more than 100 years and we predict it will continue to be essential although the tools for recording, compiling, and synthesizing data are evolving rapidly and improve data integration in the office and most recently in the field. Both traditional and future methods rely on field identification skills of the geologist to record salient new geologic data. This review describes the traditional paper- and pencil-based mapping system developed and used extensively by the Anaconda Company from 1900 to 1985 and, because of its versatility, adapted by many other geologists in industry and academia. This and similar systems allow geologically complex and diverse data to be recorded and plotted on a base map, including lithology, rock alteration and mineralization features, relative age relationships, and structural features such as faults and veins. Traditional paper-recorded geologic mapping data are now commonly converted to digital format in the office. We document use of mapping at different stages of the mine-life cycle from general regional-scale geologic mapping to regional- to district-scale exploration targeting, to deposit assessment and ore-reserve definition, through mine planning and production. Examples of mapping described herein include the Ann Mason porphyry copper deposit, Yerington district, Nevada; the Bajo de la Alumbrera mine; Argentina; the El Abra-Fortuna-Chuquicamata districts of Chile; and the Pioneer Mountains of Montana. Beyond the use of traditional paper-based mapping methods, recent technological advances include global positioning systems, pen tablet computers, palm computers, and laser ranging devices that all support direct (paperless) field-based digital geologic mapping. Improvements in computation speed, memory, data storage, battery life, durability, screen visibility, and portability have made digital mapping practical in general field mapping, mine sites, and advanced projects. Portable digital-electronic instrumentation allows the field geologist rapid access to digital data bases that include geologic maps and photographic and remotesensing imagery with automatic registration and scale independence. Another example described here, using digital mapping systems in the heavily forested portions of the Pioneer Mountains of Montana, shows how on-line GPS communicating directly to the pc tablet and digital orthophotographs made mapping sufficiently effective so as to discover a previously unknown granitic pluton with a concentric breccia zone. These new digital mapping tools may thus improve the efficiency of mapping and support a scientist in the field with unprecedented opportunities to map where field work has been difficult before. Visualization of geophysical or geochemical data together with geology and synoptic aerial imagery at any scale while mapping provides an integrated data base that facilitates identification of crucial geologic relationships. Digital techniques improve the potential for making conceptual leaps by exploring the available integrated data sets as a field geologist maps, and may in the future lead to more comprehensive three-dimensional geologic models for mineral deposits by effectively using information technology. The authors conclude that both paper and digital systems are powerful and each has certain advantages. However, the central challenge remains the training and nurturing of highly skilled field geologists motivated to practice their profession, welcoming both the rigors of intensive field work and the excitement of scientific discovery. It is surmised here that digital mapping technology may help attract an increasingly computer-literate cadre of new practitioners of mapping into mineral resource exploration.