Application of remote sensor data to geologic analysis of the Bonanza test site Colorado

Research activities on geologic remote sensing applications for Colorado are summarized. Projects include: regional and detailed geologic mapping, surficial and engineering geology, fracture studies, uranium exploration, hydrology, and data reduction and enhancement. The acquisition of remote sensor data is also discussed

A REMOTE SENSING APPROACH TO CHARACTERIZE THE HYDROGEOLOGY OF MOUNTAINOUS AREAS: APPLICATION TO THE QUITO AQUIFER SYSTEM (QAS), ECUADOR

Climate change, intensive use, and population growth are threatening the availability of water resources. New sources of water, better knowledge of existing ones, and improved water management strategies are of paramount importance. Ground water is often considered as primary water source due to its advantages in terms of quantity, spatial distribution, and natural quality. Remote sensing techniques afford scientists a unique opportunity to characterize landscapes in order to assess groundwater resources, particularly in tectonically influenced areas. Aquifers in volcanic basins are considered the most productive aquifers in Latin America. Although topography is considered the primary driving force for groundwater flows in mountainous terrains, tectonic activity increases the complexity of these groundwater systems by altering the integrity of sedimentary rock units and the overlying drainage networks. Structural controls affect the primary hydraulic properties of the rock formations by developing barriers to flow in some cases and zones of preferential infiltration and subterranean in others. The study area focuses on the Quito Aquifer System (QAS) in Ecuador. The characterization of the hydrogeology started with a lineament analysis based on a combined remote sensing and digital terrain analysis approach. The application of classical tools for regional hydrogeological evaluation and shallow geophysical methods were useful to evaluate the impact of faulting and fracturing on the aquifer system. Given the spatial extension of the area and the complexity of the system, two levels of analysis were applied in this study. At the regional level, a lineament map was created for the QAS. Relationships between fractures, faults and lineaments and the configuration of the groundwater flow on the QAS were determined. At the local level, on the Plateaus region of the QAS, a detailed lineament map was obtained by using high-spatial-resolution satellite imagery and aspect map derived from a digital elevation model (DEM). This map was complemented by the analysis of morphotectonic indicators and shallow geophysics that characterize fracture patterns. The development of the groundwater flow system was studied, drawing upon data pertaining to the aquifer system physical characteristics and topography. Hydrochemistry was used to ascertain the groundwater evolution and verify the correspondence of the flow patterns proposed in the flow system analysis. Isotopic analysis was employed to verify the origin of groundwater. The results of this study show that tectonism plays a very important role for the hydrology of the QAS. The results also demonstrate that faults influence a great deal of the topographic characteristics of the QAS and subsequently the configuration of the groundwater flow. Moreover, for the Plateaus region, the results demonstrate that the aquifer flow systems are affected by secondary porosity. This is a new conceptualization of the functioning of the aquifers on the QAS that will significantly contribute to the development of better strategies for the management of this important water resource

Dynamics of continental water storage in regions of hydrogeological interest in Colombia with implications for water security

RESUMEN: La dinámica del almacenamiento de agua terrestre es determinante para muchos fenómenos naturales y sociales, con implicaciones para la seguridad hídrica y la sostenibilidad ambiental. Aquí usamos datos de 2002–2017 del Experimento de Clima y Recuperación de Gravedad (GRACE por su sigla en inglés) para estudiar estas dinámicas en la cuenca del río Magdalena-Cauca en el noroeste de América del Sur. Mediante la comparación con estimaciones basadas en el balance hídrico, evaluamos el desempeño de múltiples productos GRACE en la representación de la dinámica del almacenamiento de agua en la cuenca, identificando el producto Mascon del Laboratorio de Propulsión Jet como el más adecuado para análisis posteriores. Luego, investigamos la existencia de tendencias a largo plazo y mostramos que el almacenamiento de agua terrestre en general y el almacenamiento de agua subterránea en particular se han ido agotando gradualmente en la cuenca desde finales de 2010. Los datos de GRACE revelan que esta tendencia no es uniforme en toda la cuenca. pero presenta un patrón bien definido en el que la tasa de agotamiento del agua es más pronunciada en las partes inferiores de la cuenca que en la superior. Exploramos los mecanismos detrás de las tendencias temporales y los patrones espaciales identificados y mostramos que el agotamiento del almacenamiento de agua coincide en gran medida con un período entre las fases extremas de La Niña y El Niño de ENOS (El Niño-Oscilación del Sur). Asimismo, el marcado contraste entre las tasas de agotamiento en las partes bajas y altas de la cuenca coincide en gran medida con marcadas diferencias biofísicas entre estas regiones, incluida la presencia de importantes sistemas de humedales en las tierras bajas y las tierras altas de las montañas andinas.ABSTRACT: Dynamics of terrestrial water storage are determinant for many natural and social phenomena, with implications for water security and environmental sustainability. Here we use 2002–2017 data from the Gravity Recovery and Climate Experiment (GRACE) to study these dynamics in the Magdalena-Cauca river basin in northwestern South America. Through comparison with water balance-based estimates, we assess the performance of multiple GRACE products in representing water storage dynamics in the basin, identifying the Mascon product from the Jet Propulsion Laboratory as the best suited for further analysis. We then investigate the existence of long term trends and show that terrestrial water storage in general and groundwater storage, in particular, have been gradually depleting in the basin since around the end of 2010. GRACE data reveal that this trend is not uniform across the basin but exhibits a clear-cut pattern in which the water depletion rate is more pronounced in the lower parts of the basin than it is in the upper basin. We explore the mechanisms behind the identified temporal trends and spatial patterns and show that water storage depletion largely coincides with a period between the La Niña and El Niño extreme phases of ENSO. Likewise, the pronounced contrast between depletion rates in the lower and higher parts of the basin largely coincides with marked biophysical differences between these regions, including the presence of major wetland systems in the lowlands, and the highlands of the Andean mountains

Literature review of the remote sensing of natural resources

Abstracts of 596 documents related to remote sensors or the remote sensing of natural resources by satellite, aircraft, or ground-based stations are presented. Topics covered include general theory, geology and hydrology, agriculture and forestry, marine sciences, urban land use, and instrumentation. Recent documents not yet cited in any of the seven information sources used for the compilation are summarized. An author/key word index is provided

Current status and long-term insights into the western Dead Sea groundwater system using multi-sensoral remote sensing

Arid regions, that have a terrestrial share of 30 %, heavily rely on groundwater for do-mestic, industrial and irrigation purposes. The reliance on groundwater has partly turned into a dependency in areas where the increasing population number and the expansion of irrigated agricultural areas demand more groundwater than is naturally replenished. Yet, spatial and temporal information on groundwater are often scarce induced by the facts that groundwater is given a low priority in many national budgets and numerous (semi-) arid regions in the world encompass large and inaccessible areas. Hence, there is an urgent need to provide low-cost alternatives that in parallel cover large spatial and temporal scales to gain information on the groundwater system. Remote sensing holds a tremendous potential to represent this alternative. The main objective of this thesis is the improvement of existing and the development of novel remote sensing applications to infer information on the scarce but indispensable resource groundwater at the example of the Dead Sea. The background of these de-velopments relies mainly on freely available satellite data sets. I investigate 1) the pos-sibility to infer potential groundwater flow-paths from digital elevation models, 2) the applicability of multi-temporal thermal satellite data to identify groundwater discharge locations, 3) the suitability of multi-temporal thermal satellite data to derive information on the long-term groundwater discharge behaviour, and 4) the differences of thermal data in terms of groundwater discharge between coarse-scaled satellite data and fine-scaled airborne data including a discharge quantification approach. 1) I develop a transparent, reproducible and objective semi-automatic approach us-ing a combined linear filtering and object based classification approach that bases on a medium resolution (30 m ground sampling distance) digital elevation model to extract lineaments. I demonstrate that the obtained lineaments have both, a hydrogeological and groundwater significance, that allow the derivation of potential groundwater flow-paths. These flow-paths match results of existing groundwater flow models remarkably well that validate the findings and shows the possibility to infer potential groundwater flow-paths from remote sensing data. 2) Thermal satellite data enable to identify groundwater discharge into open water bodies given a temperature contrast between groundwater and water body. Integrating a series of thermal data from different periods into a multi-temporal analysis accounts for the groundwater discharge intermittency and hence allows obtaining a representa-tive discharge picture. I analyse the constraints that arise with the multi-temporal anal-ysis (2000-2002) and show that ephemeral surface-runoff causes similar thermal anomalies as groundwater. To exclude surface-runoff influenced data I develop an au-tonomously operating method that facilitates the identification. I calculate on the re-maining surface-runoff uninfluenced data series different statistical measures on a per pixel basis to amplify groundwater discharge induced thermal anomalies. The results reveal that the range and standard deviation of the data series perform best in terms of anomaly amplification and spatial correspondence to in-situ determined spring dis-charge locations. I conclude on the reason that both mirror temperature variability that is stabilized and therefore smaller at areas where spatio-temporal constant groundwater discharge occurs. 3) The application of the before developed method on a thermal satellite data set spanning the years 2000 to 2011 enables to localise specific groundwater discharge sites and to semi-quantitatively analyse the temporal variability of the thermal anomalies (termed groundwater affected area - GAA). I identify 37 groundwater discharge sites along the entire Dead Sea coastline that refine the so far coarsely given spring areas to specific locations. All spatially match independent in-situ groundwater discharge observations and additionally indicate 15 so far unreported discharge sites. Comparing the variability of the GAA extents over time to recharge behaviour reveals analogous curve progressions with a time-shift of two years. This observation suggests that the thermally identified GAAs directly display the before only assumed groundwater discharge volume. This finding provides a serious alternative to monitor groundwater discharge over large temporal and spatial scales that is relevant for different scientific communities. From the results I furthermore conclude to observe the before only assumed and modelled groundwater discharge share from flushing of old brines during periods with an above average Dead Sea level drop. This observation implies the need to not only consider discharge from known terrestrial and submarine springs, but also from flushing of old-brines in order to calculate the total Dead Sea water budget. 4) I present a complementary airborne thermal data set recorded in 01/2011 over the north-western part of the Dead Sea coast. The higher spatial resolution allows to refine the satellite-based GAA to 72 specific groundwater discharge sites and even to specify the so far unknown abundance of submarine springs to six sites with a share of <10 % to the total groundwater discharge. A larger contribution stems from newly iden-tified seeping spring type (24 sites) where groundwater emerges diffusively either ter-restrial or submarine close to the land/water interface with a higher share to the total discharge than submarine springs provide. The major groundwater contribution origi-nates from the 42 identified terrestrial springs. For this spring type, I demonstrate that 93 % of the discharge volume can be modelled with a linear ordinary least square re-gression (R2=0.88) based on the thermal plume extents and in-situ measured discharge volumes from the Israel Hydrological Service. This result implies the possibility to determine discharge volumes at unmonitored sites along the Dead Sea coast as well that can provide a complete physically-based picture of groundwater discharge magni-tude to the Dead Sea for the first time.:1 Introduction 1.1 Remote sensing applications on groundwater 1.1.1 Classical aspects 1.1.2 Modern aspects 1.2 Motivation and main objectives 1.3 Why the western catchment of the Dead Sea? 1.4 Overview 2 The western catchment of the Dead Sea 2.1 Geological and Structural Overview 2.2 Groundwater system 2.3 Groundwater inputs 2.4 Dead Sea 3 Groundwater flow-paths 3.1 Prologue 4 Method development for groundwater discharge identification 4.1 Prologue 5 Localisation and temporal variability of groundwater discharge 5.1 Prologue 6 Qualitative and quantitative refinement of groundwater discharge 6.1 Prologue 7 Conclusion and Outlook 7.1 Main results and implications 7.2 Outlook References Appendi

Drilled well yield and hydraulic properties in the Precambrian crystalline bedrock of Central Finland

Siirretty Doriast

Characterization of Ethiopian mega hydrogeological regimes using GRACE, TRMM and GLDAS Datasets

Understanding the spatio-temporal characteristics of water storage changes is crucial for Ethiopia, a country that is facing a range of challenges in water management caused by anthropogenic impacts as well as climate variability. In addition to this, the scarcity of in situ measurements of soil moisture and groundwater, combined with intrinsic ‘‘scale limitations’’ of traditional methods used in hydrological characterization are further limiting the ability to assess water resource distribution in the region. The primary objective of this study is therefore to apply remotely sensed and model data over Ethiopia in order to (i) test the performance of models and remotely sensed data in modeling water resources distribution in un-gauged arid regions of Ethiopia, (ii) analyze the inter-annual and seasonal variability as well as changes in total water storage (TWS) over Ethiopia, (iii) understand the relationship between TWS changes, rainfall, and soil moisture anomalies over the study region, and (iv) identify the relationship between the characteristics of aquifers and TWS changes. The data used in this study includes; monthly gravity field data from the Gravity Recovery And Climate Experiment (GRACE) mission, rainfall data from the Tropical Rainfall Measuring Mission (TRMM), and soil moisture from the Global Land Data Assimilation System (GLDAS) model. Our investigation covers a period of 8 years from 2003 to 2011.The results of the study show that the western part and the north-eastern lowlands of Ethiopia experienced decrease in TWS water between 2003–2011, whereas all the other regions gained water during the study period. The impact of rainfall seasonality was also seen in the TWS changes. Applying the statistical method of Principal Component Analysis (PCA) to TWS, soil moisture and rainfall variations identified the dominant annual water variability in the western, north-western, northern, and central regions, and the dominant seasonal variability in the western, north-western, and the eastern regions. A correlation analysis between TWS and rainfall indicated a minimum time lag of zero to a maximum of six months, whereas no lag is noticeable between soil moisture anomalies and TWS changes. The delay response and correlation coefficient between rainfall and TWS appears to be related to recharge mechanisms, revealing that most regions of Ethiopia receive indirect recharge. Our results also show that the magnitude of TWS changes is higher in the western region and lower in the north-eastern region, and that the elevation influences soil moisture as well as TWS

Medición de subsidencia del terreno causada por sobreexplotación de acuíferos mediante herramientas GEP: A-DInSAR en la nube

[EN] Groundwater is a vitally important resource for humans. One of the main problems derived from the overexploitation of aquifers is land subsidence, which in turn carries other associated natural risks. Advanced Differential satellite radar interferometry (A-DInSAR) techniques provide valuable information on the surface displacements of the ground, which serve to characterize both the deformational behaviour of the aquifer and its properties. RESERVOIR is a research project belonging to the European PRIMA programme, whose main objective is to design sustainable groundwater management models through the study of four areas of the Mediterranean subjected to water stress. One of the main tasks of the project is the integration of the terrain deformation data obtained with satellite remote sensing techniques in the hydrogeological and geomechanical models of the aquifers. In the present work, a first evaluation of the deformation of the ground in each study area is carried out using the tools contained in the Geohazards Exploitation Platform (GEP). This is a service financed by the European Space Agency (ESA) that allows processing directly on its server, without need to store data or applications locally.[ES] Las aguas subterráneas son un recurso de vital importancia para el ser humano. Una de las principales problemáticas derivadas de la sobreexplotación de acuíferos es la subsidencia del terreno, que a su vez lleva asociados otros riesgos naturales. Las técnicas avanzadas de interferometría radar diferencial de satélite (A-DInSAR) aportan información muy valiosa sobre los desplazamientos superficiales del terreno, que sirven para caracterizar tanto el comportamiento geomecánico del acuífero como sus propiedades. RESERVOIR es un proyecto de investigación perteneciente al programa europeo PRIMA, cuyo principal objetivo es diseñar modelos sostenibles de gestión de aguas subterráneas mediante el estudio de cuatro zonas del Mediterráneo sometidas a estrés hídrico. Una de las principales tareas del proyecto es la integración de los datos de deformación del terreno obtenidos con técnicas de teledetección por satélite en los modelos hidrogeológicos y geomecánicos de los acuíferos. En el presente trabajo se realiza una primera evaluación de la deformación del terreno en cada zona de estudio utilizando las herramientas contenidas en la Geohazards Exploitation Platform (GEP). Este servicio financiado por la Agencia Espacial Europea (ESA) permite realizar procesados directamente en su servidor, sin necesidad de almacenar datos ni aplicaciones en local.This work was supported by RESERVOIR project, which is part of the PRIMA Programme supported under Horizon 2020 the European Union's Framework Programme for Research and Innovation. Grant Agreement number: [1924] [RESERVOIR] [Call 2019 Section 1 Water RIA]. Copernicus Sentinel-1 IW SAR data were provided and processed in ESA’s Geohazards Exploitation Platform (GEP), in the framework of the GEP Early Adopters Programme.Bru, G.; Ezquerro, P.; Guardiola-Albert, C.; Béjar-Pizarro, M.; Herrera, G.; Tomás, R.; Navarro-Hernández, M.... (2021). Land subsidence analysis caused by aquifer overexploitation using GEP tools: A-DInSAR on the cloud. En Proceedings 3rd Congress in Geomatics Engineering. Editorial Universitat Politècnica de València. 127-136. https://doi.org/10.4995/CiGeo2021.2021.12722OCS12713

Tracer tests, hydrochemical and microbiological investigations as a basis for groundwater protection in a remote tropical mountainous karst area, Vietnam

The Tam Duong karst area in NW Vietnam is among the poorest and remotest regions in the country. The local population largely depends on water from two main karst springs. Due to agricultural activity and untreated domestic wastewaters, the spring water is often microbiologically contaminated. In order to provide a scientific basis for groundwater protection in the area, different field methods have been applied including hydrogeological framework investigations, tracer tests, and hydrochemical and microbiological sampling and analyses. All methods had to be adapted to the conditions of a poor and remote area. These adaptations included, amongst other measures, the use of a portable microbiological water_testing kit and the involvement of the local population in the sampling campaign. The tracer tests showed simple and direct connections between two important swallow holes and the two main springs, and made it possible to determine the linear groundwater flow velocities, which are extremely high (up to 875m/h). The hydrochemical and microbiological data confirmed the strong impact of the streams sinking into the swallow holes on the spring water quality. Future groundwater source protection strategies should consequently focus on the reduction of polluting activities near the sinking streams and within their catchment area

Application of the WetSpass simulation model for determining conditions governing the recharge of shallow groundwater in the Poznań Upland, Poland

Assessments of the infiltration recharge of groundwater are performed using various methods and on different scales. Infiltration is dependent of climatic factors, aspects of water circulation, as well as on quasi-stationary and variable en- vironmental features of a specific area, which are frequently difficult to determine on the basis of direct measurements or observations. The objective of the present study was to identify factors conditioning recharge of shallow ground- water in selected catchment areas of the Poznań Upland using the WetSpass simulation water balance model with spatially distributed parameters. Our analysis has indicated favourable and unfavourable conditions for recharge of groundwater in the annual period and in both half-year periods, which are the result of mutual relationships between the physical qualities of these catchment areas and their climatic and hydrological characteristics. The results obtained also confirmed the impact of surface runoff and actual evapotranspiration on the spatial distribution of effective infiltra- tion. With soil types and groundwater depth distributions being similar in the catchment areas, changes in relationships between components of water balance are caused by differences in the type of land usage. Application of the WetSpass model has made it possible to arrive at a more accurate assessment of groundwater recharge. The results obtained may be used for erification of recharge areas and values of effective infiltration, set as a boundary condition in groundwater flow models