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A brief history of oil and gas exploration in the southern San Joaquin Valley of California:
The Golden State got its nickname from the Sierra Nevada gold that lured so many miners and settlers to the West, but California has earned much more wealth from so-called “black gold” than from metallic gold. The San Joaquin Valley has been the principal source for most of the petroleum produced in the State during the past 145 years. In attempting to assess future additions to petroleum reserves in a mature province such as the San Joaquin Basin, it helps to be mindful of the history of resource development. In this chapter we present a brief overview of the long and colorful history of petroleum exploration and development in the San Joaquin Valley. This chapter relies heavily upon the work of William Rintoul, who wrote extensively on the history of oil and gas exploration in California and especially in the San Joaquin Valley. No report on the history of oil and gas exploration in the San Joaquin Valley would be possible without heavily referencing his publications. We also made use of publications by Susan Hodgson and a U.S. Geological Survey Web site, Natural Oil and Gas Seeps in California (http://seeps.wr.usgs.gov/seeps/index.html), for much of the material describing the use of petroleum by Native Americans in the San Joaquin Valley. Finally, we wish to acknowledge the contribution of Don Arnot, who manages the photograph collection at the West Kern Oil Museum in Taft, California. The collection consists of more than 10,000 photographs that have been scanned and preserved in digital form on CD-ROM. Many of the historical photographs used in this paper are from that collection. Finally, to clarify our terminology, we use the term “San Joaquin Valley” when we refer to the geographical or topographical feature and the term “San Joaquin Basin” when we refer to geological province and the rocks therein.
Identifying factors that affect mountain lake sensitivity to atmospheric nitrogen deposition across multiple scales
Increased nitrogen (N) deposition rates over the past century have affected both North American and European mountain lake ecosystems. Ecological sensitivity of mountain lakes to N deposition varies, however, because chemical and biological responses are modulated by local watershed and lake properties. We evaluated predictors of mountain lake sensitivity to atmospheric N deposition across North American and European mountain ranges and included as response variables dissolved inorganic N (DIN = N NH 4 + + N NO 3 – ) concentrations and phytoplankton biomass. Predictors of these responses were evaluated at three different spatial scales (hemispheric, regional, subregional) using regression tree, random forest, and generalized additive model (GAM) analysis. Analyses agreed that Northern Hemisphere mountain lake DIN was related to N deposition rates and smaller scale spatial variability (e.g., regional variability between North American and European lakes, and subregional variability between mountain ranges). Analyses suggested that DIN, N deposition, and subregional variability were important for Northern Hemisphere mountain lake phytoplankton biomass. Together, these findings highlight the need for finer-scale, subregional analyses (by mountain range) of lake sensitivity to N deposition. Subregional analyses revealed differences in predictor variables of lake sensitivity. In addition to N deposition rates, lake and watershed features such as land cover, bedrock geology, maximum lake depth (Z max ), and elevation were common modulators of lake DIN. Subregional phytoplankton biomass was consistently positively related with total phosphorus (TP) in Europe, while North American locations showed variable relationships with N or P. This study reveals scale-dependent watershed and lake characteristics modulate mountain lake ecological responses to atmospheric N deposition and provides important context to inform empirically based management strategies.
Plate boundary trench retreat and dextral shear drive intracontinental fault-slip histories: Neogene dextral faulting across the Gabbs Valley and Gillis Ranges, Central Walker Lane, Nevada
The spatial-temporal evolution of intracontinental faults and the forces that drive their style, orientation, and timing are central to understanding tectonic processes. Intracontinental NW-striking dextral faults in the Gabbs Valley–Gillis Ranges (hereafter referred to as the GVGR), Nevada, define a structural domain known as the eastern Central Walker Lane located east of the western margin of the North American plate. To consider how changes in boundary type along the western margin of the North American plate influenced both the initiation and continued dextral fault slip to the present day in the GVGR, we combine our new detailed geologic mapping, structural studies, and 40 Ar/ 39 Ar geochronology with published geologic maps to calculate early to middle Miocene dextral fault-slip rates. In the GVGR, Mesozoic basement is nonconformably overlain by a late Oligocene to Miocene sequence dominated by tuffs, lavas, and sedimentary rocks. These rocks are cut and offset by four primary NW-striking dextral faults, from east to west the Petrified Spring, Benton Spring, Gumdrop Hills, and Agai Pah Hills–Indian Head faults. A range of geologic markers, including tuff- and lava-filled paleovalleys, the southern extent of lava flows, and a normal fault, show average dextral offset magnitudes of 9.6 ± 1.1 km, 7.0 ± 1.7 km, 9.7 ± 1.0 km, and 4.9 ± 1.1 km across the four faults, respectively. Cumulative dextral offset across the GVGR is 31.2 ± 2.3 km. Initiation of slip along the Petrified Spring fault is tightly bracketed between 15.99 ± 0.05 Ma and 15.71 ± 0.03 Ma, whereas slip along the other faults initiated after 24.30 ± 0.05 Ma to 20.14 ± 0.26 Ma. Assuming that slip along all four faults initiated at the same time as the Petrified Spring fault yields calculated dextral fault-slip rates of 0.4 ± 0.1–0.6 ± 0.1 mm/yr, 0.4 ± 0.1–0.5 ± 0.1 mm/yr, 0.6 ± 0.1 mm/yr, and 0.3 ± 0.1 mm/yr on the four faults, respectively. Middle Miocene initiation of dextral fault slip across the GVGR overlaps with the onset of normal slip along range-bounding faults in the western Basin and Range to the north and the northern Eastern California shear zone to the south. Based on this spatial-temporal relationship, we propose that dextral fault slip across the GVGR defines a kinematic link or accommodation zone between the two regions of extension. At the time of initiation of dextral slip across the GVGR, the plate-boundary setting to the west was characterized by subduction of the Farallon plate beneath the North American plate. To account for the middle Miocene onset of extension across the Basin and Range and dextral slip in the GVGR, we hypothesize that middle Miocene trench retreat drove westward motion of the Sierra Nevada and behind it, crustal extension across the Basin and Range and NW-dextral shear within the GVGR. During the Pliocene, the plate boundary to the west changed to NW-dextral shear between the Pacific and North American plates, which drove continued dextral slip along the same faults within the GVGR because they were fortuitously aligned subparallel to plate boundary motion.
Salt‐water intrusion in the Connecticut River
The intrusion of salt water in the lower Connecticut River Basin was studied during October 1, 1934, to June 30, 1939. The field‐ and laboratory‐work was done as a project of the Works Progress Administration under the sponsorship of the State Water Commission of the State of Connecticut. Some technical assistance was given by the Geological Survey through cooperation with the State Water Commission.
Runoff in the Santa Ynez River Basin, California, following the excessive rainfall of 1940–41
This paper reports briefly on the runoff‐characteristics of the Santa Ynez River in Santa Barbara County, California, following the excessive rainfall in the winter of 1940–41; also, it contrasts these conditions of 1940–41 with earlier years of less rainfall. The data for this report were compiled in connection with an investigation of the water‐resources of Santa Barbara County which is being conducted by the United States Geological Survey in cooperation with the County of Santa Barbara.
The influence of ground‐water storage on the runoff in the San Bernardino and eastern San Gabriel Mountains of Southern California
The steep and rugged mountains of Southern California contain considerable ground ‐ water storage . A large portion of the runoff is seepage from this storage The variations in runoff distribution depend on the geology, physiography, and soil cover of these mountain areas.
Radiocarbon evidence for extensive plate-boundary rupture about 300 years ago at the Cascadia subduction zone
The Cascadia subduction zone, a region of converging tectonic plates along the Pacific coast of North America, has a geological history of very large plate-boundary earthquakes1,2, but no such earthquakes have struck this region since Euro-American settlement about 150 years ago. Geophysical estimates of the moment magnitudes (Mw) of the largest such earthquakes range from 8 (ref. 3).to 91/2 (ref. 4). Radiocarbon dating of earthquake-killed vegetation can set upper bounds on earthquake size by constraining the length of plate boundary that ruptured in individual earthquakes. Such dating has shown that the most recent rupture, or series of ruptures, extended at least 55 km along the Washington coast within a period of a few decades about 300 years ago5. Here we report 85 new 14C ages, which suggest that this most recent rupture (or series) extended at least 900 km between southern British Columbia and northern California. By comparing the 14C ages with written records of the past 150 years, we conclude that a single magnitude 9 earthquake, or a series of lesser earthquakes, ruptured most of the length of the Cascadia subduction zone between the late 1600s and early 1800s, and probably in the early 1700s.
Massive sulfide metallogenesis at a late Mesozoic sediment-covered spreading axis: Evidence from the Franciscan complex and contemporary analogues
The Island Mountain deposit, an anomalous massive sulfide in the Central belt of the Franciscan subduction complex, northern California Coast Ranges, formed during hydrothermal activity in a sediment-dominated paleo-sea-floor environment. Although the base of the massive sulfide is juxtaposed against a 500-m-wide melange band, its gradational upper contact within a coherent sequence of sandstone, siltstone, and mudstone indicates that hydrothermal activity was concurrent with turbidite deposition. Accumulations of sulfide breccia and clastic sulfide were produced by mass wasting of the sulfide mound prior to burial by turbidites. The bulk composition of sulfide samples (pyrrhotite rich; high Cu, As, and Au contents; radiogenic Pb isotope ratios) is consistent with a hydrothermal system dominated by fluid-sediment interaction. On the basis of a comparison with possible contemporary tectonic analogues at the southern Gorda Ridge and the Chile margin triple junction, we propose that massive sulfide mineralization in the Central belt of the Franciscan complex resulted from hydrothermal activity at a late Mesozoic sediment-covered ridge axis prior to collision with the North American plate.
Citronelle Dome: A giant opportunity for multizone carbon storage and enhanced oil recovery in the Mississippi Interior Salt Basin of Alabama
The Citronelle Dome is a giant, salt-cored anticline in the eastern Mississippi Interior Salt Basin of southern Alabama that is located near several large-scale, stationary, carbon-emitting sources in the greater Mobile area. The dome forms an elliptical, four-way structural closure containing opportunities for CO2-enhanced oil recovery (CO2-EOR) and large-capacity saline reservoir CO2 sequestration. The Citronelle oil field, located on the crest of the dome, has produced more than 169 million bbl of 42-46?? API gravity oil from sandstone bodies in the Lower Cretaceous Rodessa Formation. The top seal for the oil accumulation is a thick succession of shale and anhydrite, and the reservoir is underfilled such that oil-water contacts are typically elevated 30-60 m (100-200 ft) above the structural spill point. Approximately 31-34% of the original oil in place has been recovered by primary and secondary methods, and CO2-EOR has the potential to increase reserves by up to 20%. Structural contour maps of the dome demonstrate that the area of structural closure increases upward in section. Sandstone units providing prospective carbon sinks include the Massive and Pilot sands of the lower Tuscaloosa Group, as well as several sandstone units in the upper Tuscaloosa Group and the Eutaw Formation. Many of these sandstone units are characterized by high porosity and permeability with low heterogeneity. The Tuscaloosa-Eutaw interval is capped by up to 610 m (2000 ft) of chalk and marine shale that are proven reservoir seals in nearby oil fields. Therefore, the Citronelle Dome can be considered a major geologic sink where CO2 can be safely stored while realizing the economic benefits associated with CO2-EOR. Copyright ?? 2008. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.
Fish-assemblage variation between geologically defined regions and across a longitudinal gradient in the Monkey River Basin, Belize
Linkages between geology and fish assemblages have been inferred in many regions throughout the world, but no studies have yet investigated whether fish assemblages differ across geologies in Mesoamerica. The goals of our study were to: 1) compare physicochemical conditions and fish-assemblage structure across 2 geologic types in headwaters of the Monkey River Basin, Belize, and 2) describe basin-scale patterns in fish community composition and structure for the benefit of conservation efforts. We censused headwater-pool fishes by direct observation, and assessed habitat size, structure, and water chemistry to compare habitat and fish richness, diversity, evenness, and density between streams in the variably metamorphosed sedimentary geologic type typical of 80% of Belize’s Maya Mountains (the Santa Rosa Group), and an anomalous extrusive geologic formation in the same area (the Bladen Volcanic Member). We also collected species-presence data from 20 sites throughout the basin for analyses of compositional patterns from the headwaters to the top of the estuary. Thirty-nine fish species in 21 families were observed. Poeciliids were numerically dominant, making up 39% of individuals captured, followed by characins (25%), and cichlids (20%). Cichlidae was the most species-rich family (7 spp.), followed by Poeciliidae (6 spp.). Habitat size and water chemistry differed strongly between geologic types, but habitat diversity did not. Major fish-assemblage differences also were not obvious between geologies, despite a marked difference in the presence of the aquatic macrophyte, Marathrum oxycarpum (Podostemaceae), which covered 37% of the stream bottom in high-nutrient streams draining the Santa Rosa Group, and did not occur in the low-P streams draining the Bladen Volcanic Member. Correlation analyses suggested that distance from the sea and amount of cover within pools are important to fish-assemblage structure, but that differing abiotic factors may influence assemblage structure within each geologic type. The fauna showed weak compositional zonation into 3 groups (headwaters, coastal plain, and nearshore). Nearly 20% of the fish species collected have migratory life cycles (including Joturus pichardi , Agonostomus monticola , and Gobiomorus dormitor ) that use freshwater and marine habitats. Some of these species probably rely on a natural flow regime and longitudinal connectivity for reproduction and dispersal of young, and natural flow regime and longitudinal connectivity are important factors for maintenance of functional linkages between the uplands and the coast in the ridge-to-reef corridor where the Monkey River is located. Therefore, we suggest that the viability of migratory fish populations may be a good biological indicator of upland-to-estuary connectivity important both to fishes and coastal ecosystem function. We recommend follow-up studies to substantiate the relative strengths of relationships between community structure and abiotic factors in contrasting geologies and to examine potential bottom−up responses of stream biota to the higher nutrient levels that were observed in stream waters draining the Santa Rosa Group geologic type.
Soviet books and publications on hydrology (continental) and hydrogeology: titles and some notes on obtaining Soviet monographs
A common method of publication for Soviet scientists, which partly supplants periodicals, is the publication of a collection of articles on a general area of research, frequently by members of a given institution. An extensive sampling of world geologic literature for 1961 (Hawkes, 1966) showed that 33 percent of Soviet titles appeared in periodicals whereas 55 percent of North American and 70 percent of Western European literature appeared in this form. The Soviet predilection for symposia and collections of papers makes searching for information on a given subject more difficult for Westerners because the monographs in question are often not included in exchange agreements (except informal personal ones) with Western libraries and institutions, because they may be primed in small editions, and because such publications frequently escape the notice of Western abstract journals. Unless one is fortunate enough to have many personal contacts in the Soviet Union, there seems to be little alternative to at least a rudimentary knowledge of Russian in order to stay abreast of work published as monographs and in collections.
Analytical assessments in support of the U.S. Fish and Wildlife Service 3-bat species status assessment
Beginning in February of 2020, researchers and staff of the United States Geological Survey (USGS), Bat Conservation International (BCI), Virginia Polytechnic Institute and State University, and Montana State University associated with the North American Bat Monitoring Program (NABat) collaborated with the United States Fish and Wildlife Service (USFWS) to provide technical assistance in support of the USFWS Three Bat Species Status Assessments (SSA) including the little brown bat (MYLU, Myotis lucifugus), northern long-eared bat (MYSE, Myotis septentrionalis), and tricolored bat (PESU, Perimyotis subflavus). Analytical support for the SSA was not intended to provide interpretive results, which should therefore be considered beyond the scope of this report. Technical assistance for the SSA included facilitating the USFWS data call by educating and working directly with data contributors to manage, submit, and archive a variety of bat monitoring data in the online NABat database1 using standardized data submission templates accessible through the upload features on the NABat website. Most data collected through the USFWS data call for the SSA were submitted and stored in the NABat database. These represent the efforts of hundreds of partnering organizations across more than 200 individual NABat Partner Portal Projects. A few organizations contributed data for use in these analyses that were not submitted to the NABat database. Records submitted in response to the USFWS data call included bat capture, stationary and mobile acoustic, and internal roost count data (winter and summer). Data collated in the NABat database and used for the analyses described herein are documented (NABat 2020a, NABat 2020b, NABat 2021) and available through the NABat third party request feature.
Needle twins and right-angled twins in minerals: comparison between experiment and theory
Transformation twinning in minerals forms isolated twin walls, intesecting walls with corner junctions, and wedge-shaped twins as elements of hierarchical patterns. When cut perpendicular to the twin walls, the twins have characteristic shapes, right-angled and needle-shaped wall traces, which can be observed by transmission electron microscopy or by optical microscopy. Theoretical geometries of wall shapes recently derived for strain-related systems should hold for most displacive and order-disorder type phase transitions: 1) right-angled twins show curved junctions; 2) needle-shaped twins contain flat wall segments near the needle tip if the elastic behaviour of the mineral is dominated by its anisotroyp; 3) additional bending forces and pinning effects lead to curved walls near the junction that make the needle tip appear more blunt. Bent right-angled twins were analyzed in Gd2(MoO4)3. Linear needle tips were found in WO3, [N(CH3)4]2.ZnBr4 CrAl, BiVO4, GdBa2Cu3O7, and PbZrO. Parabolic tips occur in K2Ba(NO2)4, and GeTe whereas exponential curvatures appear in BaTiO3, KSCN, Pb3(PO4)2, CaTiO3, alkali feldspars, YBa2Cu3O7, and MnAl. The size and shape of the twin microstructure relates to its formation during the phase transition and the subsequent annealing history. The mobility of the twin walls after formation depends not only on the thermal activation but also on the structure of the wall, which may be pinned to impurities on a favorable structural site. Depinnign energies are often large compared with thermal energies for diffusion. This leads to kinetic time scales for twin coarsening that are comparable to geological time scales. Therefore, transformation twins that exhibit needle domains not only indicate that the mineral underwent a structural phase transition but also contain information about its subsequent geological history.
North American Commission on Stratigraphic Nomenclature Note 69 – Application for addition of subseries/subepoch to the North American Stratigraphic Code
Consistency in stratigraphic nomenclature enables communication among scientists both regionally and globally, thus requiring the North American Stratigraphic Code, as presented by the North American Commission on Stratigraphic Nomenclature, to follow international convention. The ratification of three subseries of the Holocene by the InternationalUnion of Geological Sciences (IUGS) in June 2018 warrants the integration of subseries among formal chronostratigraphic ranks in the Code. The purpose ofmaking subseries a formal rank is that it aligns the Code with the International StratigraphicGuide, and establishes the option of using the prefixes super- and sub- for other chronostratigraphic and geochronologic ranks. This is in accordance with the guiding principle of the Code to make it as consistent as possible with international usage and to foster innovations to meet the expanding and changing needs of earth scientists.
California State Waters Map Series — Offshore of Salt Point, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. The Offshore of Salt Point map area is located in northern California, about 110 km north of San Francisco and 50 km south of Point Arena. The map area includes three California Marine Protected Areas: the southern portion of the Stewarts Point State Marine Reserve, the Salt Point State Marine Conservation Area, and the Gerstle Cove State Marine Reserve. The coast and shoreline are rugged and scenic, characterized by rocky promontories, steep bluffs capped by bare to forested marine terraces, kelp-rich coves, and nearshore rocks and pinnacles. The largely undeveloped onshore part of the map area is used primarily for grazing and recreation. U.S. Highway 1 extends along the coast through the map area, passing through Salt Point State Park, Kruse Rhododendron State Natural Reserve, and Stillwater Cove Regional Park. Sandy beaches are uncommon, present only in relatively protected coves. The seafloor in the map area extends from the shoreline to water depths of about 90 to 100 m. The nearshore to inner shelf area (to water depths of about 50 to 60 m) typically dips seaward about 1.0° to 1.5° and is underlain by bedrock and sand-sized to coarser grained sediment. The midshelf, underlain predominantly by muddy sediments, slopes more gently (less than 0.5°). Surficial and shallow sediments were deposited in the last about 21,000 years during the approximately 125-m sea-level rise that followed the last major lowstand associated with the Last Glacial Maximum, at which time the entire Offshore of Salt Point map area was emergent and the shoreline was about 20 km west of the present-day shoreline. Tectonic influences that impact the shelf morphology and geology in the map area are related to local faulting, folding, uplift, and subsidence. The onshore part of the map area is cut by the northwest-striking San Andreas Fault—the right-lateral transform boundary between the North American and Pacific tectonic plates with an estimated slip rate of about 17 to 25 mm/yr in this area. The region between Fort Ross and Point Arena, west of the San Andreas Fault, is the known as the “Gualala Block” on the basis of its distinctive geology. The Gualala Block consists of a thick, discontinuous Upper Cretaceous to Miocene stratigraphic section, however, only the submarine fan deposits of the Paleocene and Eocene German Rancho Formation are exposed along the coast in the Offshore of Salt Point map area. The German Rancho Formation also forms all of the rugged seafloor bedrock outcrops in the map area. The western boundary of the Gualala Block lies 3 to 5 km offshore, perhaps at the shore-parallel Gualala Fault. High-resolution seismic-reflection data reveal shallow folding and faulting in inferred upper Pleistocene strata along the Gualala Fault trend, suggesting this structure is now or has been recently active. The last ground rupture in the map area occurred during the devastating great 1906 California earthquake (M7.8, 4/18/1906), thought to have nucleated on the San Andreas Fault about 100 kilometers to the south offshore of San Francisco. Circulation over the continental shelf in the map area is dominated by the southward-flowing California Current, the eastern limb of the North Pacific Gyre. Associated upwelling brings cool, nutrient-rich waters to the surface, resulting in high biological productivity. The current flow generally is southeastward during the spring and summer; however, during the fall and winter, the otherwise persistent northwest winds are sometimes weak or absent, causing the California Current to move farther offshore and the Davidson Current, a weaker, northward-flowing countercurrent, to become active. Throughout the year, this part of the central California coast is exposed to four wave climate regimes: the north Pacific swell, the southern swell, northwest wind waves, and local wind waves. The north Pacific swell dominates in winter months, with wave heights at offshore buoys ranging from 2 to 10 m and wave periods ranging from 10 to 25 s. During summer months, the largest waves come from the southern swell, generated by storms in the south Pacific and offshore Central America. Characteristically, these swells have smaller wave heights (0.3 to 3 m) and similarly long periods (range 10 to 25 s). Northwest wind waves affect the coast throughout the year, while local wind waves are most common from October to April. These two wind-wave regimes typically have wave heights of 1 to 4 m and short periods (3 to 10 s). Potential marine benthic habitats in the Offshore of Salt Point map area include unconsolidated continental shelf sediments, mixed continental shelf substrate, and hard continental shelf substrate. Rocky-shelf outcrops and rubble are considered to be promising potential habitats for rockfish and lingcod, both of which are recreationally and commercially important species.
Geologic map of the State of Hawai`i
The State's geology is presented on eight full-color map sheets, one for each of the major islands. These map sheets, the illustrative meat of the publication, can be downloaded in pdf format, ready to print. Map scale is 1:100,000 for most of the islands, so that each map is about 27 inches by 36 inches. The Island of Hawai`i, largest of the islands, is depicted at a smaller scale, 1:250,000, so that it, too, can be shown on 36-inch-wide paper. The new publication isn't limited strictly to its map depictions. Twenty years have passed since David Clague and Brent Dalrymple published a comprehensive report that summarized the geology of all the islands, and it has been even longer since the last edition of Gordon Macdonald's book, Islands in the Sea, was revised. Therefore the new statewide geologic map includes an 83-page explanatory pamphlet that revisits many of the concepts that have evolved in our geologic understanding of the eight main islands. The pamphlet includes simplified page-size geologic maps for each island, summaries of all the radiometric ages that have been gathered since about 1960, generalized depictions of geochemical analyses for each volcano's eruptive stages, and discussion of some outstanding topics that remain controversial or deserving of additional research. The pamphlet also contains a complete description of map units, which enumerates the characteristics for each of the state's many stratigraphic formations shown on the map sheets. Since the late 1980s, the audience for geologic maps has grown as desktop computers and map-based software have become increasingly powerful. Those who prefer the convenience and access offered by Geographic Information Systems (GIS) can also feast on this publication. An electronic database, suitable for most GIS software applications, is available for downloading. The GIS database is in an Earth projection widely employed throughout the State of Hawai`i, using the North American datum of 1983 and the Universal Transverse Mercator system projection to zone 4. 'This digital statewide map allows engineers, consultants, and scientists from many different fields to take advantage of the geologic database,' said John Sinton, a geology professor at the University of Hawai`i, whose new mapping of the Wai`anae Range (West O`ahu) appears on the map. Indeed, when a testing version was first made available, most requests came from biologists, archaeologists, and soil scientists interested in applying the map's GIS database to their ongoing investigations. Another area newly depicted on the map, in addition to the Wai`anae Range, is Haleakala volcano, East Maui. So too for the active lava flows of Kilauea volcano, Island of Hawai`i, where the landscape has continued to evolve in the ten years since publication of the Big Island's revised geologic map. For the other islands, much of the map is compiled from mapping published in the 1930-1960s. This reliance stems partly from shortage of funding to undertake entirely new mapping but is warranted by the exemplary mapping of those early experts. The boundaries of all map units are digitized to show correctly on modern topographic maps.
Report of committee on glaciers, April 1939
The Committee on Glaciers at present is constituted as follows: Harry Fielding Reid—Professor‐Emeritus of Geology, Johns Hopkins University (former member of the International Glacier Commission), 608 Cathedral Street, Baltimore, Maryland William H. Hobbs—Professor‐Emeritus of Geology, University of Michigan (until recently Vice‐ President of the International Glacier Commission, at present associate member), Ann Arbor, Michigan J. E. Church—Professor of Classics, University of Nevada (President of the International Commission of Snow, and Chairman of the Committee on Snow of the Section of Hydrology, American Geophysical Union), Reno, Nevada Colonel Lawrence Martin—Chief of the Division of Maps, Library of Congress, Washington, D. C. Wm. Osgood Field, Jr.—Explorer, 18 West Twelfth Street, New York, N.Y. Earl A. Trager—Chief of the Naturalist Division, National Park Service, Washington, D. C. Glenn L. Parker—District Engineer, Water Resources Branch, United States Geological Survey, 406 Federal Building, Tacoma, Washington Oliver Kehrlein—Chairman, Committee on Glacier Studies, Sierra Club, 1050 Mills Tower, San Francisco, California Kenneth N. Phillips—Associate Hydraulic Engineer, Water Resources Branch, United States Geological Survey, Chairman, Research Committee of the Mazamas, 606 Post‐Office Building, Portland, Oregon William S. Cooper—Professor of Botany, University of Minnesota, Minneapolis, Minnesota Gerald FitzGerald, Senior Topographic Engineer, Alaska Branch, United States Geological Survey, Washington, D.C. Laurence M. Gould, Professor of Geology, Carleton College, Northfield, Minnesota François E. Matthes, Chairman , Senior Geologist, Section of Glacial Geology, United States Geological Survey (titular member of the International Glacier Commission), Washington, D.C. In 1938, as in previous years, the Committee devoted its energies primarily to the collecting of data on the variations in length and volume of American glaciers, it being felt that the maintenance of a continuous record of these variations is of prime importance, not only to hydrology and glaciology, but, as has become increasingly evident recently, also to climatology, geomorphology, geography, ecology, history, and archaeology. As the time available for the work of the Committee is limited and does not permit covering the entire field of glaciology, it seems best to devote it before all else to this line of research which yields results of value to so many different sciences. Besides, the gathering of data on glacier‐oscillations is not a one‐man job that can be taken up or dropped at convenience from time to time, but is an organized and far‐flung enterprise whose success depends upon the faithful cooperation of many volunteer workers located in different parts of the country. Such an enterprise, once launched, must be kept running or it will disintegrate and the precious enthusiasm of the field‐workers will be lost.