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USGS1978

A selected bibliography: Remote sensing applications for tropical and subtropical vegetation analysis

This bibliography contains 425 citations of selected technical reports, journal articles, and other publications covering the general subject of tropical and subtropical vegetation analysis. Functionally related topics that include vegetation analysis are included for completeness, and citations have been organized under the following subheadings for ease of reference: remote sensing application overviews, vegetation (general), forestry, grasslands/savannah/shrublands, agriculture, land use/thematic mapping, and integrated surveys/multiple resource analysis/land systems. The terms "tropics and subtropics" are used in the widest context to include applications related to a broad range of equatorial environments. The bibliography contains selected citations published between 1924 and 1978. Many foreign language and non U.S.- source items are included.

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USGS2000

Water quality in the Allegheny and Monongahela River basins, Pennsylvania, West Virginia, New York, and Maryland, 1996-98

Major influences and findings for ground water quality, surface water quality, and biology in the Allegheny and Monongahela River basins are described and illustrated. Samples were collected in a variety of media to determine trace elements, sulfate, pesticides, nitrate, volatile organic compounds, organochlorine compounds, and radon-222. This report discusses the influences of several land-use practices, such as coal mining, urbanization, agriculture, and forestry. The report also includes a summary of a regional investigation of water quality and quality invertebrates in the Northern and Central Appalachian coal regions.

Maryland, New York, Pennsylvania, West Virginia↗

USGS2006

Drought of 1998-2002: impacts on Florida's hydrology and landscape

Lower than normal precipitation caused a severe statewide drought in Florida from 1998 to 2002. Based on precipitation and streamflow records dating to the early 1900s, the drought was one of the worst ever to affect the State. In terms of severity, this drought was comparable to the drought of 1949-1957 in duration and had record-setting low flows in several basins. The drought was particularly severe over the 5-year period in the northwest, northeast, and southwest regions of Florida, where rainfall deficits ranged from 9-10 in. below normal (southwest Florida) to 38-40 in. below normal (northwest Florida). Within these regions, the drought caused record-low streamflows in several river basins, increased freshwater withdrawals, and created hazardous conditions ripe for wildfires, sinkhole development, and even the draining of lakes. South Florida was affected primarily in 2001, when the region experienced below-average streamflow conditions; however, cumulative rainfall in south Florida never fell below the 30-year normal. The four regions of Florida, as referred to throughout this report, are defined based upon U.S. Geological Survey (USGS) data collection regions in Florida. Record-low flows were reported at several streamflow-gaging stations throughout the State, including the Withlacoochee River at Trilby, which reached zero flow on June 10-11, 2000, for the first time during the period of record (1928-2004). Streamflow conditions varied across the State from 31 percent of average flow in 2000 in southwest Florida, to 100 percent of average in 1999 in south Florida. Low-flow recurrence intervals during the drought ranged from less than 2 years at three locations to greater than 50 years at many locations. During the 1998-2002 drought, ground-water levels at many wells across the State declined to elevations not seen in many years. At some wells, ground-water levels reached record lows for their period of record. Florida Water Management Districts responded by issuing water-shortage mandates to curb water use during the spring months of 2000. Generally, freshwater withdrawals increased 13 percent between 1995 and 2000 as a result of the dry conditions. Hundreds of new sinkholes developed across the State. Lake Jackson, in northwest Florida near Tallahassee, experienced its eighth and ninth drawdowns of the past 100 years, and became nearly dry. Numerous other lakes in northern and central Florida experienced similar events. Water restrictions were put into effect in urban areas of the northeast, southwest, and south Florida regions. Wildfires periodically raged over parts of Florida throughout the period, when tinder-dry undergrowth caught fire from lightning strikes or manmade causes. Smoke from these fires caused traffic delays as sections of major highways and interstate lanes forced traffic to slow to a crawl or were closed. Wildfire statistics (Florida Division of Forestry) show that 25,137 fires burned 1.5 million acres between 1998 and 2002. Finally, rainfall that occurred in late 2002, in 2003, and from a tropical storm and four hurricanes in 2004 ended this drought.

Circular↗

USGS2013

U.S. Geological Survey ecosystems science strategy—Advancing discovery and application through collaboration

Executive Summary Ecosystem science is critical to making informed decisions about natural resources that can sustain our Nation’s economic and environmental well-being. Resource managers and policymakers are faced with countless decisions each year at local, regional, and national levels on issues as diverse as renewable and nonrenewable energy development, agriculture, forestry, water supply, and resource allocations at the urban-rural interface. The urgency for sound decisionmaking is increasing dramatically as the world is being transformed at an unprecedented pace and in uncertain directions. Environmental changes are associated with natural hazards, greenhouse gas emissions, and increasing demands for water, land, food, energy, mineral, and living resources. At risk is the Nation’s environmental capital, the goods and services provided by resilient ecosystems that are vital to the health and wellbeing of human societies. Ecosystem science—the study of systems of organisms interacting with their environment and the consequences of natural and human-induced change on these systems—is necessary to inform decisionmakers as they develop policies to adapt to these changes. This Ecosystems Science Strategy is built on a framework that includes basic and applied science. It highlights the critical roles that U.S. Geological Survey (USGS) scientists and partners can play in building scientific understanding and providing timely information to decisionmakers. The strategy underscores the connection between scientific discoveries and the application of new knowledge, and it integrates ecosystem science and decisionmaking, producing new scientific outcomes to assist resource managers and providing public benefits. We envision the USGS as a leader in integrating scientific information into decisionmaking processes that affect the Nation’s natural resources and human well-being. The USGS is uniquely positioned to play a pivotal role in ecosystem science. With its wide range of expertise, the Bureau can bring holistic, cross-scale, interdisciplinary capabilities to the design and conduct of monitoring, research, and modeling and to new technologies for data collection, management, and visualization. Collectively, these capabilities can be used to reveal ecological patterns and processes, explain how and why ecosystems change, and forecast change over different spatial and temporal scales. USGS science can provide managers with options and decision-support tools to use resources sustainably. The USGS has long-standing, collaborative relationships with the Department of the Interior (DOI) and other partners in the natural sciences, in both conducting science and applying the results. The USGS engages these partners in cooperative investigations that otherwise would lack the necessary support or be too expensive for a single bureau to conduct. The heart of this strategy is a framework for USGS ecosystems science that focuses on five long-term goals, which are seen as interconnected components that reinforce our vision of the USGS providing science that is at the forefront of decisionmaking: Improve understanding of ecosystem structure, function, and processes. The focus for this goal is an understanding of how ecosystems work, including the dynamics of species, their populations, interactions, and genetics, and how they change across spatial and temporal scales. Advance understanding of how drivers influence ecosystem change. The challenges here are explaining the drivers of ecosystem change, their spatio-temporal patterns, their uncertainties and interactions, and their influence on ecosystem processes and dynamics. Improve understanding of the services that ecosystems provide to society. Here the emphasis is on the measurement of environmental capital and ecosystem services, and the identification of sources and patterns of change in space and time. Develop tools, technologies, and capacities to inform decisionmaking about ecosystems. This includes developing new technologies and approaches for conducting applications-oriented ecosystem science. A principal challenge will be how to quantify uncertainty and incorporate it in decision analysis. Apply science to enhance strategies for management, conservation, and restoration of ecosystems. These challenges include development of novel approaches to monitoring, assessment, and restoration of ecosystems; new methods to address species of concern and communities at risk; and innovations in decision analysis and support to address imminent ecosystem changes or those that are underway. Closely integrated with the five goals are four strategic approaches that provide the path forward for the USGS Ecosystems Mission Area. These approaches cross-cut all of the goals and are seen as essential to the implementation of this strategy: Assess information needs for ecosystem science through enhanced partnerships. Work with the DOI and other agencies and institutions to identify, design, and implement priority decision-driven ecological research. Promote the use of interdisciplinary ecosystem science. Design and conduct interdisciplinary process-oriented research in ecosystem science. Enhance modeling and forecasting. Build models to forecast ecosystem change, assess future management scenarios, and reduce uncertainties through an adaptive learning process. Support decisionmaking. Use quantitative approaches to assess the vulnerabilities of ecosystems, habitats, and species, and evaluate strategies for adaptation, restoration, and sustainable management. Following the four strategic approaches are a set of proposed actions that represent a sampling of specific USGS activities that align with this strategy and that address the Nation’s most pressing environmental needs. The strategy emphasizes coordination of activities across the USGS mission areas pursuant to these goals. Ecosystem science is inherently interdisciplinary and requires a broad perspective that incorporates the biological and physical sciences, climate science, information technology, and scientific capacity in mission areas across the Bureau. With its emphasis on coordination, this strategy can provide a critical underpinning for integrated science efforts with scientists from multiple mission areas of the USGS working together. Of course, the USGS will continue to conduct discipline-specific and interdisciplinary investigations, and both will continue to be vital parts of the ecosystem science portfolio. Finally, the strategy stresses the importance of coordination with other Federal agencies and organizations in the natural resources community. The USGS collaborates with resource agencies in the DOI and other organizations throughout the world to meet societal needs for species and ecosystem management. Working with these agencies and organizations, the USGS will play a key role in guiding sound decisionmaking during the next decade by advancing the scientific foundation for sustaining the natural resources that diverse, productive, resilient ecosystems provide.

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USGS2015

U.S. conterminous wall-to-wall anthropogenic land use trends (NWALT), 1974–2012

This dataset provides a U.S. national 60-meter, 19-class mapping of anthropogenic land uses for five time periods: 1974, 1982, 1992, 2002, and 2012. The 2012 dataset is based on a slightly modified version of the National Land Cover Database 2011 (NLCD 2011) that was recoded to a schema of land uses, and mapped back in time to develop datasets for the four earlier eras. The time periods coincide with U.S. Department of Agriculture (USDA) Census of Agriculture data collection years. Changes are derived from (a) known changes in water bodies from reservoir construction or removal; (b) housing unit density changes; (c) regional mining/extraction trends; (d) for 1999–2012, timber and forestry activity based on U.S. Geological Survey (USGS) Landscape Fire and Resource Management Planning Tools (Landfire) data; (e) county-level USDA Census of Agriculture change in cultivated land; and (f) establishment dates of major conservation areas. The data are compared to several other published studies and datasets as validation. Caveats are provided about limitations of the data for some classes. The work was completed as part of the USGS National Water-Quality Assessment (NAWQA) Program and termed the NAWQA Wall-to-Wall Anthropogenic Land Use Trends (NWALT) dataset. The associated datasets include five 60-meter geospatial rasters showing anthropogenic land use for the years 1974, 1982, 1992, 2002, and 2012, and 14 rasters showing the annual extent of timber clearcutting and harvest from 1999 to 2012.

Data Series↗

USGS2015

Landsat—Earth observation satellites

Since 1972, Landsat satellites have continuously acquired space-based images of the Earth’s land surface, providing data that serve as valuable resources for land use/land change research. The data are useful to a number of applications including forestry, agriculture, geology, regional planning, and education. Landsat is a joint effort of the U.S. Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA). NASA develops remote sensing instruments and the spacecraft, then launches and validates the performance of the instruments and satellites. The USGS then assumes ownership and operation of the satellites, in addition to managing all ground reception, data archiving, product generation, and data distribution. The result of this program is an unprecedented continuing record of natural and human-induced changes on the global landscape.

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USGS2019

Landsat 9

Landsat 9 is a partnership between the National Aeronautics and Space Administration and the U.S. Geological Survey that will continue the Landsat program’s critical role of repeat global observations for monitoring, understanding, and managing Earth’s natural resources. Since 1972, Landsat data have provided a unique resource for those who work in agriculture, geology, forestry, regional planning, education, mapping, and global-change research. Landsat images have also proved invaluable to the International Charter: Space and Major Disasters, supporting emergency response and disaster relief to save lives. With the addition of Landsat 9, the Landsat program’s record of land imaging will be extended to over half a century.

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USGS2022

South Carolina and Landsat

South Carolina, the eighth State admitted to the union, transcends its size with its deep, rich history; striking beauty; vast natural resources; and extensive cultural diversity. Home to part of the Blue Ridge Mountains of the Central Appalachians, the Upstate is graced with more than 100 waterfalls, while the Lowcountry borders the Atlantic Ocean with 187 miles of coastline and 35 barrier islands. Forests cover two-thirds of the State, and forestry and agriculture together, as agribusiness, make up South Carolina’s leading industry. Two historic crops—cotton and tobacco—still rank in the top 10 commodities, though corn and soybeans now rank higher. Poultry, cattle, peanuts, and flowers also make the list. South Carolina’s population totals more than five million. Other residents include a variety of wildlife, bird, reptile, and fish species, including Ursus americanus (black bears), Alligator mississippiensis (American alligators), and Tursiops truncatus (bottlenose dolphins). More than 100 tree species also reside in South Carolina, which pays homage to one with its “The Palmetto State” nickname. South Carolina’s subtropical climate, long coastline, and lower elevations make it highly susceptible to tornado and hurricane activity and coastal flooding. Projected sea-level rise is a growing concern. A view from space can help monitor and manage natural resources on the land and in rivers, marshes, and the coast. Landsat reveals not just what an area looks like now, but also insights from decades ago.

South Carolina↗

USGS2023

The 3D Elevation Program—Supporting Oregon's economy

Introduction Oregon’s physical environments and vegetation are diverse. The varied geologic and climatic conditions combined with increasing population have created the need for high-quality elevation data that can be used for infrastructure management, forestry and wildfire management, agriculture, natural resources conservation, and other business uses. Critical applications that meet the State’s management needs depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features.

Oregon↗

USGS2024

The 3D Elevation Program—Supporting Florida's economy

Introduction Florida has the longest coastline of any State in the contiguous United States, and its coastal resources are one of the main drivers of its economic growth. High-quality elevation data are beneficial for use in emergency management, especially for hurricane response, recovery, and mitigation, as well as for coastal zone management, flood risk management, infrastructure planning, agriculture, forestry, and natural resources management. Having regional or statewide elevation data coverage that was collected at about the same time allows for improved results from in-depth modeling and more meaningful analysis to support the State’s Chief Science Officer, Geographic Information Officer, State agencies, water management districts, and local governments that will use these data for decision making. Critical applications that meet the State’s management needs depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features.

Florida↗

USGS2024

The 3D Elevation Program—Supporting Mississippi's economy

Introduction Mississippi has a dispersed population of nearly three million residents in an area of approximately 48,400 square miles and has a favorable climate for agriculture, with abundant precipitation and minimal extreme temperatures. The topography consists mostly of low hills and lowland plains, with the highest elevation about 800 feet above sea level. An exception is the nearly flat Mississippi Alluvial Plain, or “Delta,” in the northwestern part of the State. Agriculture and forestry are Mississippi’s major industries. With 65 percent of its area forested, the State is one of the country’s top producers of lumber and wood-related products. In addition to agriculture and forest resources management, other important economic activities are infrastructure and construction management, flood risk management, and water supply and quality assessment. High-quality elevation data can help to support these activities. Critical applications that meet the State’s management needs depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features.

Mississippi↗

USGS2010

Using land-cover change as dynamic variables in surface-water and water-quality models

Land-cover data are typically used in hydrologic modeling to establish or describe land surface dynamics. This project is designed to demonstrate the use of land-cover change data in surface-water and water-quality models by incorporating land-cover as a variable condition. The project incorporates three different scenarios that vary hydrologically and geographically: 1) Agriculture in the Plains, 2) Loon habitat in New England, and 3) Forestry in the Ozarks.

General Information Product↗

USGS2001

A guide to potential soil carbon sequestration: Land-use management for mitigation of greenhouse gas emissions

Terrestrial carbon sequestration has a potential role in reducing the recent increase in atmospheric carbon dioxide (CO2) that is, in part, contributing to global warming. Because the most stable long-term surface reservoir for carbon is the soil, changes in agriculture and forestry can potentially reduce atmospheric CO2 through increased soil-carbon storage. If local governments and regional planning agencies are to effect changes in land-use management that could mitigate the impacts of increased greenhouse gas (GHG) emissions, it is essential to know how carbon is cycled and distributed on the landscape. Only then can a cost/benefit analysis be applied to carbon sequestration as a potential land-use management tool for mitigation of GHG emissions. For the past several years, the U.S. Geological Survey (USGS) has been researching the role of terrestrial carbon in the global carbon cycle. Data from these investigations now allow the USGS to begin to (1) 'map' carbon at national, regional, and local scales; (2) calculate present carbon storage at land surface; and (3) identify those areas having the greatest potential to sequester carbon.

North Carolina↗

USGS2006

Calculation of area and volume for the north part of Great Salt Lake, Utah

The U.S. Geological Survey, in cooperation with the Utah Department of Natural Resources, Division of Forestry, Fire, and State Lands, collected bathymetric data for the north part of Great Salt Lake during the spring and early summer of 2006 using a single-beam, high-definition fathometer and real-time differential global positioning system. About 5.2 million depth measurements were collected along more than 765 miles (1,230 kilometers) of survey transects. Sound-velocity profiles were obtained in conjunction with the bathymetric data to provide time-of-travel corrections to the depth calculations. Data were processed with commercial hydrographic software and exported into geographic information system (GIS) software for mapping and calculation of area and volume. Area and volume calculations show a maximum area of about 385,000 acres (1,560 square kilometers) and a maximum volume of about 5,693,000 acre-feet (about 7 cubic kilometers) at a water-surface altitude of 4,200 feet (1,280 meters). Minimum natural water-surface altitude of the north part of Great Salt Lake is just below 4,167 feet (1,270 meters) in the area just north of the Union Pacific railroad causeway halfway between Saline and the western edge of the lake. The north part of Great Salt Lake generally grades gradually to the west and north and is bounded by steep scarps along its eastern border. Calculations for area and volume are based on a low altitude of 4,167 feet (1,270 meters) to a high altitude of 4,200 feet (1,280 meters).

Utah↗

USGS2007

Forest Bird Distribution, Density and Trends in the Ka'u Region of Hawai'i Island

An accurate and current measure of population status and trend is necessary for conservation and management efforts. Scott and Kepler (1985) provided a comprehensive review of the status of native Hawaiian birds based on the extensive Hawaii Forest Bird Survey (HFBS) of the main islands (Scott et al. 1986). At that time, they documented declining populations and decreasing ranges for most species, and the extinction of several species over the previous 50 years. Many native bird species continue to decline throughout Hawai`i (Camp et al. In review, Gorresen et al. In prep.). The focus of this study is the mid-to-high elevation rainforest on the southeast windward slopes of Mauna Loa Volcano (Figure 1). Known as Ka`u, the region encompasses forest lands protected by Kamehameha Schools, The Nature Conservancy, Hawai`i Volcanoes National Park (HVNP), and the State of Hawai'i's Ka`u Forest Reserve, Kapapala Forest Reserve and Kapapala Cooperative Game Management Area,. Together these lands support one of three main concentrations of native forest birds on the Hawai`i Island (the other two being centered on the Hakalau Forest National Wildlife Refuge and Kulani-Keauhou area in the north and central windward part of the island, respectively.) Because this region harbors important populations of native and endangered forest birds in some of the best remaining forest habitat on the island, it has been a focus of forest bird surveys since the 1970s. The Ka`u region was first quantitatively surveyed in 1976 by the Hawaii Forest Bird Survey (Scott et al. 1986). Surveys were conducted by State of Hawai`i Division of Forestry and Wildlife in 1993 and 2002 and by the U.S. National Park Service and the U.S. Geological Survey in 2004 and 2005. In this report, we present analyses of the density, distribution and trends of native and introduced forest bird within the Ka`u region of Hawai`i Island. The analyses cover only those species with sufficient detections to model detection probability and calculate density. These include three endangered native passerines: `Akiapola`au (Hemignathus munroi), Hawai`i Creeper (Oreomystis mana), and Hawai`i `Akepa (Loxops coccineus); five more common native passerines: the Hawai`i `Elepaio (Chasiempis sandwichensis), `Oma`o (Myadestes obscurus), Hawai`i `Amakihi (Hemignathus virens), `I`iwi (Vestiaria coccinea) and `Apapane (Himatione sanguinea); and three non-native species: Red-billed Leiothrix (Leiothrix lutea), Japanese White-eye (Zosterops japonicus), and Northern Cardinal (Cardinalis cardinalis).

Open-File Report↗

USGS2010

An analysis of the risk of introduction of additional strains of the rust puccinia psidii Winter ('Ohi'a Rust) to Hawai'i

In April 2005, the rust fungus Puccinia psidii (most widely known as guava rust or eucalyptus rust) was found in Hawai'i. This was the first time this rust had been found outside the Neotropics (broadly-defined, including subtropical Florida, where the rust first established in the 1970s). First detected on a nursery-grown 'ohi'a plant, it became known as ''ohi'a rust'in Hawai'i. The rust spread rapidly and by August 2005 had been found throughout the main Hawaiian Islands. The rust probably reached Hawai'i via the live plant trade or via the foliage trade. In Hawai'i, the rust has infected three native plant species and at least eight non-native species. Effects have been substantial on the endangered endemic plant Eugenia koolauensis and the introduced rose apple, Syzygium jambos. Billions of yellow, asexual urediniospores are produced on rose apple, but a complete life cycle (involving sexual reproduction) has not yet been observed. The rust is autoecious (no alternate host known) on Myrtaceae. The strain introduced into Hawai'i is found sparingly on 'ohi'a (Metrosideros polymorpha), the dominant tree of Hawai'i's forests, with sporadic damage detected to date. The introduction of a rust strain that causes widespread damage to 'ohi'a would be catastrophic for Hawai'i's native biodiversity. Most imports of material potentially contaminated with rust are shipped to Hawai'i from Florida and California (from which P. psidii was reported in late 2005 by Mellano, 2006). Florida is known to have multiple strains. The identity of the strain or strains in California is unclear, but one of them is known to infect myrtle, Myrtus communis, a species commonly imported into Hawai'i. It is important to ecosystem conservation and commercial forestry that additional rust strains or genotypes be prevented from establishing in Hawai'i. The purpose of this analysis of risk is to evaluate the need for an interim rule by the Hawai'i Department of Agriculture to regulate plant material of Myrtaceae arriving from the continental United States and to clarify consequences of such a rule, especially implications for possible eventual action by the U.S. Department of Agriculture, Animal and Plant Health Inspection Service, to assist in protection of Hawai'i's native and non-native Myrtaceae from plant pests.

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USGS2008

The Global Flows of Metals and Minerals

This paper provides a preliminary review of the trends in worldwide metals and industrial minerals production and consumption based on newly developed global metals and minerals Material Flow Accounts (MFA). The MFA developed encompass data on extraction and consumption for 25 metal and mineral commodities, on a country-by-country and year-by-year basis, for the period 1970 to 2004. The data-base, jointly developed by the authors, resides with the U.S. Geological Survey (USGS) as individual commodity Excel workbooks and within a Filemaker data management system for use in analysis. Numerous national MFA have been developed to provide information on the industrial metabolism of individual countries. These MFA include material flows associated with the four commodity categories of goods that are inputs to a country's economy, agriculture, forestry, metals and minerals, and nonrenewable organic material. In some cases, the material flows associated with the creation and maintenance of the built infrastructure (such as houses, buildings, roads, airports, dams, and so forth) were also examined. The creation of global metals and industrial minerals flows is viewed as a first step in the creation of comprehensive global MFA documenting the historical and current flows of all of the four categories of physical goods that support world economies. Metals and minerals represent a major category of nonrenewable resources that humans extract from and return to the natural ecosystem. As human populations and economies have increased, metals and industrial minerals use has increased concomitantly. This dramatic growth in metals and minerals use has serious implications for both the availability of future resources and the health of the environment, which is affected by the outputs associated with their use. This paper provides an overview of a number of the trends observed by examining the database and suggests areas for future study.

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USGS2018

A practical primer on geostatistics

Introduction The Challenge —Most geological phenomena are extraordinarily complex in their interrelationships and vast in their geographical extension. Ordinarily, engineers and geoscientists are faced with corporate or scientific requirements to properly prepare geological models with measurements involving a small fraction of the entire area or volume of interest. Exact description of a system such as an oil reservoir is neither feasible nor economically possible. The results are necessarily uncertain. Note that the uncertainty is not an intrinsic property of the systems; it is the result of incomplete knowledge by the observer. The Aim of Geostatistics —The main objective of geostatistics is the characterization of spatial systems that are incompletely known, systems that are common in geology. A key difference from classical statistics is that geostatistics uses the sampling location of every measurement. Unless the measurements show spatial correlation, the application of geostatistics is pointless. Ordinarily the need for additional knowledge goes beyond a few points, which explains the display of results graphically as fishnet plots, block diagrams, and maps. Geostatistical Methods —Geostatistics is a collection of numerical techniques for the characterization of spatial attributes using primarily two tools: probabilistic models, which are used for spatial data in a manner similar to the way in which time-series analysis characterizes temporal data, or pattern recognition techniques. The probabilistic models are used as a way to handle uncertainty in results away from sampling locations, making a radical departure from alternative approaches like inverse distance estimation methods. Differences with Time Series —On dealing with time-series analysis, users frequently concentrate their attention on extrapolations for making forecasts. Although users of geostatistics may be interested in extrapolation, the methods work at their best interpolating. This simple difference has significant methodological implications. Historical Remarks —As a discipline, geostatistics was firmly established in the 1960s by the French engineer Georges Matheron, who was interested in the appraisal of ore reserves in mining. Geostatistics did not develop overnight. Like other disciplines, it has built on previous results, many of which were formulated with different objectives in various fields. Pioneers —Seminal ideas conceptually related to what today we call geostatistics or spatial statistics are found in the work of several pioneers, including: 1940s: A.N. Kolmogorov in turbulent flow and N. Wiener in stochastic processing; 1950s: D. Krige in mining; 1960s: B. Mathern in forestry and L.S. Gandin in meteorology Calculations —Serious applications of geostatistics require the use of digital computers. Although for most geostatistical techniques rudimentary implementation from scratch is fairly straightforward, coding programs from scratch is recommended only as part of a practice that may help users to gain a better grasp of the formulations. Software —For professional work, the reader should employ software packages that have been thoroughly tested to handle any sampling scheme, that run as efficiently as possible, and that offer graphic capabilities for the analysis and display of results. This primer employs primarily the package Stanford Geomodeling Software (SGeMS) - recently developed at the Energy Resources Engineering Department at Stanford University - as a way to show how to obtain results practically. This applied side of the primer should not be interpreted as the notes being a manual for the use of SGeMS. The main objective of the primer is to help the reader gain an understanding of the fundamental concepts and tools in geostatistics. Organization of the Primer —The chapters of greatest importance are those covering kriging and simulation. All other materials are peripheral and are included for better comprehension of these main geostatistical modeling tools. The choice of kriging versus simulation is often a big puzzle to the uninitiated, let alone the different variants of both of them. Chapters 14, 18, and 19 are intended to shed light on those subjects. The critical aspect of assessing and modeling spatial correlation is covered in chapter 7. Chapters 2 and 3 review relevant concepts in classical statistics. Course Objectives —This course offers stochastic solutions to common problems in the characterization of complex geological systems. At the end of the course, participants should have: an understanding of the theoretical foundations of geostatistics; a good grasp of its possibilities and limitations; and reasonable familiarity with the SGeMS software, thus opening the possibility of practically applying geostatistics.

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