SEARCH · USGS Science
Results for “Natural History”
Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Landscape esthetics: How to quantify the scenics of a river valley
There are an increasing number of bills before Congress that in one way or another affect the landscape or the environment. Each of these requires seemingly endless numbers of congressional hearings, which are recorded upon endless reams of paper. And if, for some reason, you happen to read the voluminous testimony surrounding one of these environment-affecting proposals, you will generally find a marked contrast between the volume and kind of information presented by those who are pressing for technical development - building a dam, constructing a highway, installing a nuclear power plant - and the testimony of those who either oppose the development or wish to alter it in some way. The developer usually employs numerical arguments, which tend to show that there is an economic benefit to be obtained by constructing something - whatever that something may be. The argument is usually expressed in terms of a "cost-benefit ratio." It is typically argued, for instance, that the construction cost of a given project will be repaid over a period of time and will yield a profit or a benefit in excess of the development costs by a ratio of, let us say, 1.2 to 1. The argument is further supported with great numbers of charts, graphs, tables, and additional figures. In marked contrast, those who favor protection of the environment against development are fewer in number, their statements are based on emotion or personal feelings, and they usually lack numerical information, quantitative data, and detailed computations. Perhaps this is the reason why this latter group seems to be continually fighting rearguard actions - losing battle after battle.
Let's Sing 'Auld Lang Syne' for the Upper Brandywine: Or, to continue with Burns, how the best laid environmental schemes of men "gang aft a-gley"
Perhaps the most lamentable mistake that one can make is to be right too soon. This was the story of the Brandywine Plan, an attempt to organize local people for the permanent protection of the environmental amenities of their own land. The Upper East Branch of Brandywine Creek drains a rolling basin of farms, fields, woodlands, and a sprinkling of residential areas. Because it lies at the far edge of the commuting range to the population centers of Philadelphia and Wilmington, the basin's natural beauty has barely been touched by the blight of suburban sprawl. The waters of its streams are clear; its ample woodlands and fields are filled with wildlife. Driving slowly through the basin's winding roads and across its narrow bridges evokes the feeling of a pastoral painting, of the ideal landscape of rural eastern America. For two years, I had the privilege of working closely with a group preparing a land plan for the Brandywine area. The plan was designed to offer the inhabitants of the basin a feasible way to preserve forever the natural qualities of their region from the inevitable wave of urbanization. A report in Science magazine called it the perfect plan that failed.
Hydrogeology of Virginia
The hydrogeology of Virginia documented herein is in two parts. Part 1 consists of an overview and description of the hydrogeology within each regional aquifer system in the Commonwealth. Part 2 includes discussions of hydrogeologic research topics of current relevance including: 1. the Chesapeake Bay impact structure, 2. subsidence/compaction in the Coastal Plain, 3. groundwater age and aquifer susceptibility, 4. the occurrence of groundwater at depth in fractured-rock and karst terrains, and 5. hydrologic response of wells to earthquakes around the world.
What Became of the Water on Mars?
Focuses on several exploratory missions to the planet Mars to investigate the role of water within the planet. Facts about Mars that were gathered from two National Aeronautics and Space Administration orbiters, the Mars Global Surveyor and Mars Odyssey; Features of Mars that are similar with the planet Earth; Factors that contribute to the possible existence of water in Mars; Background on the geology of Mars.
Gopherus Agassizii (Agassiz’s Desert Tortoise). Overwinter movement
No abstract available.
Evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico
Dinosaur fossils from the Ojo Alamo Sandstone, San Juan Basin, New Mexico, have been a puzzle to geologists for decades because other stratigraphic and paleontologic evidence indicates that this formation is Paleocene in age. The Paleocene age of the Ojo Alamo is based on the following evidence: (1) the lowermost part of the Nacimiento Formation, which conformably overlies and intertongues with the Ojo Alamo Sandstone in the Ojo Alamo type area in the southern part of the basin, contains Paleocene (Puercan) mammalian fossils; (2) plant megafossils collected from the Ojo Alamo indicate a Tertiary age for this rock unit; (3) pollen-productive rock samples collected from the Ojo Alamo at several localities in the basin have, without exception, yielded Paleocene-age palynomorph assemblages, and conversely, no Cretaceous pollen has ever been reported from Ojo Alamo rock samples. We report here the first discovery of Paleocene palynomorphs from Ojo Alamo Sandstone outcrops in the northern San Juan Basin. The pollen-producing rock samples were collected from a coaly, carbonaceous shale bed 12-m above the base of the Ojo Alamo and 3-m below the level of a large hadrosaur femur (1310-mm long and weighing about 130 kg) collected from this site. The bone was recovered from a cobble-to-boulder conglomeratic sandstone but shows no evidence of abrasion by erosion indicating almost instant burial after death of the animal and early mineralization of the femur. It is our opinion that this bone was not reworked from underlying Cretaceous strata. The data from the San Juan River site indicate that dinosaurs did not die out at the end of the Cretaceous in the San Juan Basin, but lived on for as much as a few hundred thousand years into the Paleocene before finally becoming extinct.
Discriminating between natural vs induced seismicity from long-term deformation history of intraplate faults
To assess whether recent seismicity is induced by human activity or is of natural origin, we analyze fault displacements on high-resolution seismic reflection profiles for two regions in the central United States (CUS): the Fort Worth Basin (FWB) of Texas, and the northern Mississippi embayment (NME). Since 2009 earthquake activity in the CUS has increased dramatically, and numerous publications suggest that this increase is primarily due to induced earthquakes caused by deep-well injection of wastewater, both flowback water from hydrofracturing operations and produced water accompanying hydrocarbon production. Alternatively, some argue that these earthquakes are natural, and that the seismicity increase is a normal variation that occurs over millions of years. Our analysis shows that within the NME, faults deform both Quaternary alluvium and underlying sediments dating from Paleozoic through Tertiary, with displacement increasing with geologic unit age, documenting a long history of natural activity. In the FWB, a region of ongoing wastewater injection, basement faults show deformation of the Proterozoic and Paleozoic units, but little or no deformation of younger strata. Specifically, vertical displacements in the post-Pennsylvanian formations, if any, are below the resolution (~15 m) of the seismic data, far less than expected had these faults accumulated deformation over millions of years. Our results support the assertion that recent FWB earthquakes are of induced origin; this conclusion is entirely independent of analyses correlating seismicity and wastewater injection practices. To our knowledge this is the first study to discriminate natural and induced seismicity using classical structural geology analysis techniques.
International decade for natural disaster reduction
Throughout history, humanity has found itself in conflict with naturally occurring events of geologic, hydrologic, and atmospheric origin. this conflict has been demonstrated repeatedly when people build urban centers at the water's edge, in or near active fault systems capable of generating earthquakes, on steep slopes, near active volcanoes, or at the urban-wilderness interface prone to wildfires. Naturally occurring, recurrent events such as floods, windstorms, tsunamis, earthquakes, landslides, volcanic eruptions, and wildfires have tested human-engineered works many times and have often found them unable to withstand the forces generated by the event. In the past 20 years, for example, events like these throughout the world have claimed more than 2.8 million lives and adversely affected 820 million people; single disasters have caused economic losses of billions of dollars. Industrialized countries like the United States and Japan have been able to absorb the socioeconomic losses of past natural disasters, but the economics of many developing countries have been devastated by losses equal to a large percentage of their gross national product. Furthermore, the magnitude of the losses is increasing at a rapid rate as the building wealth of nations is expanded to meet the needs of rapidly increasing population, often without adequate consideration of the potential threat posed by the recurrent natural hazards and without implementing effective loss-reduction measures because of lack of knowledge or lack of technical capability.
Human impact on the planet: an earth system science perspective and ethical considerations
The modern Earth Narrative, the scientific story of the 4.5 billion-year natural and human history of the Earth, has emerged from the solid foundation of two factual concepts: Deep (or Geologic) Time and Biological Evolution. spread acceptance of the Earth Narrative is critically important as we begin the third millennium, because it provides a clear understanding of the growing impact of human population growth and associated activities on the Earth System, especially the negative impact on Earth?s biosphere. It is important for humans to realize that we are but one of 4,500 species of mammals that exist on Earth and that we are but one species in the estimated 30 to 100 million species that form the complex biosphere. We also need to recognize that all species exist within the physical limits imposed by the geosphere. We are totally dependent on the biosphere for food, oxygen, and other necessities of life. mans are one of the latest results of biological evolution operating over a long period of Geologic Time. We find ourselves on Earth, after 4.5 billion years of Earth history by chance, not by design. Humans have become so successful at modifying their environment that many of the natural limitations on the expansion of populations of our fellow animals have been overcome by technological and cultural innovations. According to Peter Raven, ?Humans, at a current population of 6 billion [expected to nearly double by 2050], are consuming or wasting about 50 percent of the total net biological productivity on land and 50 percent of the available supply of freshwater. The overwhelming and expanding human presence leaves less and less room in the environment for other biota.? st century will be a pivotal time in the fate of Earth?s biosphere. Whereas human modification of the geosphere will slowly recover over time, human changes to the biosphere are a far more consequential matter? extinction of a species is forever! Will humans effectively use our new knowledge of natural and human history to stop further degradation of Earth?s ecosystems and extinction of its biota? The fate of the biosphere, including humanity, depends on a reaffirmation by all humans of all cultures and religions of the global importance of a planet-wide conservation of the Earth?s biotic heritage. For the world?s religions it means elevation of stewardship of the Earth to a moral imperative and a goal of complete preservation of the Earth?s biotic inheritance, one which is based on a Do No Harm ethic.
The human dimension of fire regimes on Earth
Humans and their ancestors are unique in being a fire‐making species, but ‘natural’ (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human‐set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from ‘natural’ background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke‐related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas‐induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding of the development and diversification of fire regimes, covering the pre‐human period, human domestication of fire, and the subsequent transition from subsistence agriculture to industrial economies. All of these phases still occur on Earth, providing opportunities for comparative research.
Recruitment bottlenecks for age-0 walleye in northern Wisconsin lakes
Some northern Wisconsin lakes have shown declines in catches of age-0 Walleye Sander vitreus in standardized fall electrofishing sampling, suggesting that recruitment bottlenecks are occurring in the first several months of life. In 2016 and 2017, we sampled six lakes with declining trends in natural Walleye recruitment (D-NR lakes) and seven lakes with a history of sustained natural recruitment (S-NR lakes) to determine if timing of potential recruitment bottlenecks for age-0 Walleye were consistent among D-NR lakes and if abiotic and biotic metrics differed between D-NR and S-NR lakes. We also examined diets of larval Walleye to assess prey items that may be important to early growth and survival and to determine if occurrence of piscivory was related to larval Walleye total length. Differential patterns in the presence and absence of age-0 Walleye at different life history stages in the first 6 months of life suggested that recruitment bottlenecks in D-NR lakes were consistently occurring before mid-July (five of six lakes). Mean Secchi depth, surface conductivity, abundance of larval Yellow Perch Perca flavescens , and most metrics of zooplankton abundance and mean size were similar between D-NR and S-NR lakes. Log 10 transformed number of adult Walleye per hectare was lower and adult mean total length was higher in D-NR lakes. Across all lakes, diets of larval Walleye consisted of zooplankton and larval fish and the occurrence of piscivory was higher than reported in previous studies and was positively related to total length of larval Walleye. Causes of recruitment bottlenecks in D-NR lakes remain unclear, making it difficult to identify management actions that might be implemented to circumvent these bottlenecks. However, our results indicate that future research should focus on the period between egg deposition and mid-July.
Natural offshore oil seepage and related tarball accumulation on the California coastline — Santa Barbara Channel and the southern Santa Maria Basin; source identification and inventory
Oil spillage from natural sources is very common in the waters of southern California. Active oil extraction and shipping is occurring concurrently within the region and it is of great interest to resource managers to be able to distinguish between natural seepage and anthropogenic oil spillage. The major goal of this study was to establish the geologic setting, sources, and ultimate dispersal of natural oil seeps in the offshore southern Santa Maria Basin and Santa Barbara Basins. Our surveys focused on likely areas of hydrocarbon seepage that are known to occur between Point Arguello and Ventura, California. Our approach was to 1) document the locations and geochemically fingerprint natural seep oils or tar; 2) geochemically fingerprint coastal tar residues and potential tar sources in this region, both onshore and offshore; 3) establish chemical correlations between offshore active seeps and coastal residues thus linking seep sources to oil residues; 4) measure the rate of natural seepage of individual seeps and attempt to assess regional natural oil and gas seepage rates; and 5) interpret the petroleum system history for the natural seeps. To document the location of sub-sea oil seeps, we first looked into previous studies within and near our survey area. We measured the concentration of methane gas in the water column in areas of reported seepage and found numerous gas plumes and measured high concentrations of methane in the water column. The result of this work showed that the seeps were widely distributed between Point Conception east to the vicinity of Coal Oil Point, and that they by in large occur within the 3-mile limit of California State waters. Subsequent cruises used sidescan and high resolution seismic to map the seafloor, from just south of Point Arguello, east to near Gaviota, California. The results of the methane survey guided the exploration of the area west of Point Conception east to Gaviota using a combination of seismic instruments. The seafloor was mapped by sidescan sonar, and numerous lines of high -resolution seismic surveys were conducted over areas of interest. Biomarker and stable carbon isotope ratios were used to infer the age, lithology, organic matter input, and depositional environment of the source rocks for 388 samples of produced crude oil, seep oil, and tarballs mainly from coastal California. These samples were used to construct a chemometric fingerprint (multivariate statistics) decision tree to classify 288 additional samples, including tarballs of unknown origin collected from Monterey and San Mateo County beaches after a storm in early 2007. A subset of 9 of 23 active offshore platform oils and one inactive platform oil representing a few oil reservoirs from the western Santa Barbara Channel were used in this analysis, and thus this model is not comprehensive and the findings are not conclusive. The platform oils included in this study are from west to east: Irene, Hildago, Harvest, Hermosa, Heritage, Harmony, Hondo, Holly, Platform A, and Hilda (now removed). The results identify three “tribes” of 13 C-rich oil samples inferred to originate from thermally mature equivalents of the clayey-siliceous, carbonaceous marl, and lower calcareous-siliceous members of the Monterey Formation. Tribe 1 contains four oil families having geochemical traits of clay-rich marine shale source rock deposited under suboxic conditions with substantial higher-plant input. Tribe 2 contains four oil families with intermediate traits, except for abundant 28,30-bisnorhopane, indicating suboxic to anoxic marine marl source rock with hemipelagic input. Tribe 3 contains five oil families with traits of distal marine carbonate source rock deposited under anoxic conditions with pelagic but little or no higher-plant input. Tribes 1 and 2 occur mainly south of Point Conception in paleogeographic settings where deep burial of the Monterey Formation source rock favored generation from all three members or their equivalents. In this area, oil from the clayey-siliceous and carbonaceous marl members (Tribes 1 and 2) may overwhelm that from the lower calcareous-siliceous member (Tribe 3) because the latter is thinner and less oil-prone than the overlying members. Tribe 3 occurs mainly north of Point Conception, where shallow burial caused preferential generation from the underlying lower calcareous-siliceous member or another unit with similar characteristics. It is very desirable to be able to clearly distinguish the naturally occurring seep oils from the anthropogenically derived platform oils. Within the “training set” of oils and tars (388 samples), the biomarker parameters are sometimes sufficient to allow unique discrimination of individual platform oils. More often however, platform samples and seep samples with sources geographically close to each other are too similar to each other, with respect to the biomarker parameters, to definitively differentiate them on that basis alone. In some cases other parameters can be helpful. These other parameters are related to the degree of biogeochemical degradation or weathering that the oils or tars have experienced. These components include the typical oil distribution of n-alkane hydrocarbons and isoprenoids pristane and phytane. All of the platform oils in our sample set contain these components. On the other hand, the seep oils or tars have been exposed to significant biodegradation while in the near subsurface. The majority, but not all of seep oils or tars have been biodegraded up to or beyond the loss of n-alkanes and isoprenoids. Seep oils found in the vicinity of Coal Oil Point or Arroyo Burro are apparently the least weathered and are particularly likely to retain significant n-alkanes and isoprenoids. Therefore the combination of chemometric fingerprinting and the presence or absence of n-alkanes and isoprenoids help to differentiate anthropogenic production oils versus natural seeps oils and tars. The differentiation is not always definitive because of the close chemical similarity of some samples and the variability in the biodegradation progression. This is the case near Coal Oil Point, and near Platform A (Dos Cuadros Field) where seep oils and Platform Holly and Platform A oils are genetically very similar and cannot be definitively distinguished after a period of a few days of weathering. In contrast, oils from the Point Conception platforms can be distinguished on the basis of chemometric fingerprinting alone. In the middle of this spectrum are oils from Platforms Harmony, Heritage, and Hondo, where it is expected that oil weathering would take on the order of two weeks to a month to produce tarballs similar to those seen near Point Conception. In this case there is a much greater degree of weathering needed to proceed from produced oil to the biodegraded tar characteristic of tarball stranded on the beach. Tar deposition on beaches was monitored as part of cooperative with the County of Santa Barbara Energy Division and the U.S. Geological Survey during 2001-2003. We found tar deposition varies on a seasonal basis. In general, tarballs accumulate at a faster rate or remain longer on all beaches during the summer and fall months. The reasons for this are unclear based on our limited observations, however we speculate that factors such as prevailing winds and currents combined with more quiescent wave conditions favors the accumulation and preservation of tarballs on the beach during the summer and fall months. In contrast, winter storms, with much greater wave action remove beach sand and other materials, and stormy seas tend to break up oil that might weather into tarballs. Natural seepage is affected by the spring/neap tidal cycle; however, the link to tar deposition is unclear. Longer periods of monitoring are needed to address the variability in the data and provide a more robust statistical analysis.
Book Review: Preserving nature in the national parks - A history
No abstract available.
Natural heat storage in a brine-filled solar pond in the Tully Valley of central New York
The Tully Valley, located in southern Onondaga County, New York, has a long history of unusual natural hydrogeologic phenomena including mudboils (Kappel, 2009), landslides (Tamulonis and others, 2009; Pair and others, 2000), landsurface subsidence (Hackett and others, 2009; Kappel, 2009), and a brine-filled sinkhole or “Solar pond” (fig. 1), which is documented in this report. A solar pond is a pool of salty water (brine) which stores the sun’s energy in the form of heat. The saltwater naturally forms distinct layers with increasing density between transitional zones (haloclines) of rapidly changing specific conductance with depth. In a typical solar pond, the top layer has a low salt content and is often times referred to as the upper convective zone (Lu and others, 2002). The bottom layer is a concentrated brine that is either convective or temperature stratified dependent on the surrounding environment. Solar insolation is absorbed and stored in the lower, denser brine while the overlying halocline acts as an insulating layer and prevents heat from moving upwards from the lower zone (Lu and others, 2002). In the case of the Tully Valley solar pond, water within the pond can be over 90 degrees Fahrenheit (°F) in late summer and early fall. The purpose of this report is to summarize observations at the Tully Valley brine-filled sinkhole and provide supplemental climate data which might affect the pond salinity gradients insolation (solar energy).