Merumite was discovered with associated diamonds and gold in 1937 in gravels of the Merume River in Guyana. It was described as essentially a hydrous chromium oxide that contains more than 80 percent Cr2Oa. Milton and Chao in 1958 found it to be a complex aggregate, mainly eskolaite (Cr2Oa) with five or more new chromium minerals which have recently been identified. The deposit is unique. The richest gravel, averaging several ounces merumite per cubic yard, extends about 2 miles along the base of an east-dipping (35°) ridge of sandstone and ash beds, perhaps an outlier of the Precambrian Roraima Formation that forms bold mountainous scarps a few miles south. No chromium mineralization has been observed in the ridge or anywhere in the region, other than the merumite in the placer gravel. Merumite commonly occurs as grains a few millimeters across, but specimens as large as 10 cm have been found. Almost all the merumite is in rounded grains, many with broken worn edges, indicating wear in transport. Granular gold is enclosed in merumite, as is chromian pyrophyllite. Many merumite grains have impressions, and some contain crystals, of doubly terminated \"needle\" quartz. Water-worn gorceixite, rutile, tourmaline-quartz fels, jasper, euhedral glassy quartz (as much as several centimeters long), and fragments of basaltic rock accompany merumite at all localities; rarely, gold and diamonds are associated in the placers. Merumite was probably derived from a local moderate-temperature hydrothermal deposit possibly formed in the adjacent sandstone-volcanic ash bed from solutions related to local ash deposits and massive gabbro-dolerite intrusive bodies in the Roraima Formation. If the deposit was formed at depths of less than a few thousand feet, erosion may have reached it and re-deposited the merumite and accompanying resistant minerals, mostly'quartz and jasper, in local stream beds. © 1969 Society of Economic Geologists, Inc.
","language":"English ","publisher":"Elsevier","doi":"10.2113/gsecongeo.64.8.910","issn":"03610128","usgsCitation":"Milton, C., and Narain, S., 1969, Merumite occurrence in Guyana: Economic Geology, v. 64, no. 8, p. 910-914, https://doi.org/10.2113/gsecongeo.64.8.910.","productDescription":"5 p. ","startPage":"910","endPage":"914","costCenters":[],"links":[{"id":368914,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Guyana ","otherGeospatial":"Merume River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -59.3756103515625,\n 5.4683637496808535\n ],\n [\n -57.864990234375,\n 5.4683637496808535\n ],\n [\n -57.864990234375,\n 7.035475652433024\n ],\n [\n -59.3756103515625,\n 7.035475652433024\n ],\n [\n -59.3756103515625,\n 5.4683637496808535\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"64","issue":"8","noUsgsAuthors":false,"publicationDate":"1969-12-01","publicationStatus":"PW","contributors":{"authors":[{"text":"Milton, C.","contributorId":37472,"corporation":false,"usgs":true,"family":"Milton","given":"C.","affiliations":[],"preferred":false,"id":774536,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Narain, S","contributorId":220228,"corporation":false,"usgs":false,"family":"Narain","given":"S","email":"","affiliations":[],"preferred":false,"id":774537,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70199506,"text":"70199506 - 1969 - Effect of rainfall variability on streamflow simulation","interactions":[],"lastModifiedDate":"2018-09-19T15:52:59","indexId":"70199506","displayToPublicDate":"1969-10-01T15:52:23","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"Effect of rainfall variability on streamflow simulation","docAbstract":"Three recording rain gages in a 9.7‐square‐mile basin in southern California were used with a deterministic rainfall‐runoff model to simulate flood hydrographs and peaks and to assess the effects of data errors on simulation results. Bias in the estimation of effective basin rainfall seemed to result in curve fitting parameter adjustments which compensated for the bias. The combined effects for a storm of both difference in the time distribution of rainfall at different points and spatial variability of rainfall volume over the basin limit the possible accuracy of simulation results. The use of a single rain gage on a basin with this hydrology can at best be expected to predict peak discharge with a standard error of estimate on the order of 20%.
","publisher":"American Geologists Union","doi":"10.1029/WR005i005p00958","usgsCitation":"Dawdy, D., and Bergmann, J.M., 1969, Effect of rainfall variability on streamflow simulation: Water Resources Research, v. 5, no. 5, p. 958-966, https://doi.org/10.1029/WR005i005p00958.","productDescription":"9 p.","startPage":"958","endPage":"966","costCenters":[],"links":[{"id":357512,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"California","volume":"5","issue":"5","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","contributors":{"authors":[{"text":"Dawdy, D.R.","contributorId":99956,"corporation":false,"usgs":true,"family":"Dawdy","given":"D.R.","affiliations":[],"preferred":false,"id":745628,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bergmann, James M.","contributorId":12471,"corporation":false,"usgs":true,"family":"Bergmann","given":"James","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":745629,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70224621,"text":"70224621 - 1969 - The structure and tectonic history of the eastern Aleutian Trench","interactions":[],"lastModifiedDate":"2021-09-30T17:34:49.906947","indexId":"70224621","displayToPublicDate":"1969-10-01T12:24:36","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"The structure and tectonic history of the eastern Aleutian Trench","docAbstract":"The tectonic character of the eastern Aleutian Trench and some major events in its geologic history can be estimated from nine continuous seismic reflection records. A section of pre-trench, deep oceanic sediments rests on the down-warped crust that forms the trench. Nearly horizontal undeformed strata that unconformably overlie this deep oceanic section partially fill the trench. The trench fill is thickest near present sediment sources. A Pliocene age for development of the eastern Aleutian Trench is estimated from the thickness of deep oceanic sediment that accumulated after the trench began to fill. The eastern Aleutian Trench thus appears younger than the central Aleutian Trench—a relation which helps to explain the distribution of sediment along the two trench segments.
Depression of the eastern Aleutian Trench diminished or virtually ended soon after the trench began to fill. The undeformed fill provides no evidence for a large thrust fault zone at the base of the continental slope. Nor is there any evidence that oceanic sediments have disappeared beneath the continents in late Tertiary time. These observations are difficult to reconcile with the simple model of a continental margin advanced in the hypothesis of plate tectonics.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1969)80[1889:TSATHO]2.0.CO;2","usgsCitation":"von Huene, R.E., and Shor, G.G., 1969, The structure and tectonic history of the eastern Aleutian Trench: Geological Society of America Bulletin, v. 80, no. 10, p. 1889-1902, https://doi.org/10.1130/0016-7606(1969)80[1889:TSATHO]2.0.CO;2.","productDescription":"16 p.","startPage":"1889","endPage":"1902","costCenters":[],"links":[{"id":390048,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Aleutian Trench, Gulf of Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -169.3212890625,\n 52.855864177853974\n ],\n [\n -169.0576171875,\n 52.07950600379697\n ],\n [\n -153.80859375,\n 55.89995614406812\n ],\n [\n -144.580078125,\n 60.673178565817715\n ],\n [\n -150.205078125,\n 61.75233128411639\n ],\n [\n -169.365234375,\n 53.85252660044951\n ],\n [\n -169.3212890625,\n 52.855864177853974\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"80","issue":"10","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"von Huene, Roland E. 0000-0003-1301-3866 rvonhuene@usgs.gov","orcid":"https://orcid.org/0000-0003-1301-3866","contributorId":191070,"corporation":false,"usgs":true,"family":"von Huene","given":"Roland","email":"rvonhuene@usgs.gov","middleInitial":"E.","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true},{"id":7065,"text":"USGS emeritus","active":true,"usgs":false}],"preferred":false,"id":824385,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Shor, George G. Jr.","contributorId":266140,"corporation":false,"usgs":false,"family":"Shor","given":"George","suffix":"Jr.","email":"","middleInitial":"G.","affiliations":[{"id":16196,"text":"Scripps Institution of Oceanography, La Jolla, CA","active":true,"usgs":false}],"preferred":false,"id":824386,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70224280,"text":"70224280 - 1969 - A geophysical study of North Park and the surrounding ranges, Colorado","interactions":[],"lastModifiedDate":"2021-09-20T11:55:39.253471","indexId":"70224280","displayToPublicDate":"1969-08-01T06:42:29","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"A geophysical study of North Park and the surrounding ranges, Colorado","docAbstract":"A geophysical study in the North Park basin and surrounding mountains, Colorado illustrates the structural relationship of various sedimentary, metamorphic, and igneous rock units. Bouguer anomalies from 1330 gravity stations range from −210 mgal over Precambrian metamorphic rocks in the mountains to −260 mgal in the Walden syncline and —280 mgal in the North Park syncline. Steep gradients delineate a fault which strikes west-northwest along the north flank of the North Park syncline. Two models fitted to the gravity data show 1 to 2 km relief on this steeply dipping fault. Density contrasts between Precambrian metamorphic and igneous rocks produce anomalies of as much as 25-mgal amplitudes in the Park and Medicine Bow Ranges.
A 30-km-long seismic refraction profile, parallel to the most negative Bouguer anomaly values in the North Park basin, shows velocities increasing from 2.5 to 3.4 km/sec within Tertiary rocks at depths ranging from 1.2 to 2.0 km. Mesozoic sedimentary rocks have a velocity of 4.0 to 4.5 km/sec, a very high velocity in view of the predominance of Upper Cretaceous rocks. Precambrian basement with a velocity of 6.25 km/sec underlies the profile at depths ranging from 3.5 to 4.5 km. Strong second arrivals across the profile, observed at distances of more than 14 km from the shotpoints and interpreted as SP reflections, verified the refraction model.
An aeromagnetic survey shows numerous anomalies ranging from 100 to 200γ in the Park and Rabbit Ears Ranges and in the Never Summer Mountains, to 400γ in the Front Range, and to 1200γ over the Medicine Bow Range. Positive anomalies in the Park, Medicine Bow, and Front ranges overlie metamorphic rocks. Magnetic and gravity data suggest that the Never Summer Mountains are separated from the Front Range by a north-trending, steeply east-dipping reverse fault, extending beneath the Front Range along the Colorado River valley. The magnetic data indicate that this fault may connect with a possible fault that is parallel to the Laramie River valley. In the Rabbit Ears Range, a series of magnetic anomalies show that igneous rocks are present in the eastern part of the range.
A northeast-trending positive magnetic anomaly, which is parallel to foliation trends reported in Precambrian rocks, extends from the Park Range across the North Park basin to the Medicine Bow Range. On the basis of this anomaly, the high seismic velocity of the Precambrian basement, and computed profiles fitted to the gravity and magnetic data, we infer that much of the basin is underlain by high-density metamorphic rock. As shown by gravity data, the deepest part of the basin is 2.7 km below sea level, resulting in a maximum relief of 6.7 km on the basement, relative to the Medicine Bow Range.
A 25-mgal negative gravity anomaly and a zone of negative magnetic anomalies outline a large granitic intrusion in the Park Range, which probably extends northeast beneath the North Park basin and connects with granitic rocks in the Medicine Bow Range.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1969)80[1523:AGSONP]2.0.CO;2","usgsCitation":"Behrendt, J.C., Popenoe, P., and Mattick, R.E., 1969, A geophysical study of North Park and the surrounding ranges, Colorado: Geological Society of America Bulletin, v. 80, no. 8, p. 1523-1537, https://doi.org/10.1130/0016-7606(1969)80[1523:AGSONP]2.0.CO;2.","productDescription":"17 p.","startPage":"1523","endPage":"1537","costCenters":[{"id":218,"text":"Denver Federal Center","active":false,"usgs":true}],"links":[{"id":389461,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","otherGeospatial":"Front Range, Medicine Bow Range, Never Summer Mountains, North Park basin, Rabbit Ears Range, Park Range","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -106.78573608398438,\n 40.225024210604964\n ],\n [\n -105.74615478515625,\n 40.225024210604964\n ],\n [\n -105.74615478515625,\n 40.99544751505735\n ],\n [\n -106.78573608398438,\n 40.99544751505735\n ],\n [\n -106.78573608398438,\n 40.225024210604964\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"80","issue":"8","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Behrendt, John C. jbehrendt@usgs.gov","contributorId":25945,"corporation":false,"usgs":true,"family":"Behrendt","given":"John","email":"jbehrendt@usgs.gov","middleInitial":"C.","affiliations":[{"id":213,"text":"Crustal Imaging and Characterization Team","active":false,"usgs":true},{"id":218,"text":"Denver Federal Center","active":false,"usgs":true}],"preferred":false,"id":823443,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Popenoe, Peter","contributorId":52180,"corporation":false,"usgs":true,"family":"Popenoe","given":"Peter","affiliations":[],"preferred":false,"id":823444,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Mattick, Robert E.","contributorId":50462,"corporation":false,"usgs":true,"family":"Mattick","given":"Robert","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":823445,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70211006,"text":"70211006 - 1969 - Distribution of scandium between coexisting biotite and hornblende in igneous rocks","interactions":[],"lastModifiedDate":"2020-07-10T13:00:36.505674","indexId":"70211006","displayToPublicDate":"1969-07-05T13:34:16","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1723,"text":"GSA Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Distribution of scandium between coexisting biotite and hornblende in igneous rocks","docAbstract":"Scandium analyses of more than 90 pairs of coexisting biotite and hornblende from igneous rocks of various provinces (including Southern California, Boulder, Sierra Nevada, Boulder Creek batholiths and the Jemez Mountains volcanic rocks) indicate that the distribution ratio (Kd = Schornblende/Scbiotite) for most samples closely approached that of an equilibrium distribution. Median Kd values for the igneous samples range from 4.8 to 8.0, which are higher than similar values derived from published data on metamorphic samples and apparently not related to the mode of crystallization (volcanic, hypabyssal, or plutonic). A correlation between Kd and mafic index, (FeO + Fe2O3)/(FeO + Fe2O3 + MgO) X 100, of both the minerals and the host rock, and between Kd and SiO2 content of the host rock, can be established only for the Southern California batholith samples. However, whether this correlation reflects temperature dependence, compositional dependence, or both, cannot be specified uniquely with present data. The present data also cast doubt on the validity of the so-called “scandium geothermometer.”
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1969)80[651:DOSBCB]2.0.CO;2","usgsCitation":"Tilling, R.I., Greenland, L.P., and Gottfried, D., 1969, Distribution of scandium between coexisting biotite and hornblende in igneous rocks: GSA Bulletin, v. 80, no. 4, p. 651-668, https://doi.org/10.1130/0016-7606(1969)80[651:DOSBCB]2.0.CO;2.","productDescription":"18 p.","startPage":"651","endPage":"668","costCenters":[{"id":153,"text":"California Volcano Observatory","active":false,"usgs":true}],"links":[{"id":376225,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"80","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Tilling, Robert I. 0000-0003-4263-7221 rtilling@usgs.gov","orcid":"https://orcid.org/0000-0003-4263-7221","contributorId":2567,"corporation":false,"usgs":true,"family":"Tilling","given":"Robert","email":"rtilling@usgs.gov","middleInitial":"I.","affiliations":[],"preferred":true,"id":792404,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Greenland, L. Paul","contributorId":22488,"corporation":false,"usgs":true,"family":"Greenland","given":"L.","email":"","middleInitial":"Paul","affiliations":[],"preferred":false,"id":792405,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gottfried, D.","contributorId":92346,"corporation":false,"usgs":true,"family":"Gottfried","given":"D.","email":"","affiliations":[],"preferred":false,"id":792406,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70224600,"text":"70224600 - 1969 - Errors in using modern stream-load data to estimate natural rates of denudation","interactions":[],"lastModifiedDate":"2021-09-29T16:49:51.602886","indexId":"70224600","displayToPublicDate":"1969-07-01T11:33:42","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Errors in using modern stream-load data to estimate natural rates of denudation","docAbstract":"The practice of calculating natural rates of denudation from routinely collected data on the loads of suspended and dissolved matter in modern rivers is subject to several significant errors. The sources of these errors are demonstrated by examples from the Atlantic drainage of the United States, where their total effect has apparently doubled the natural rate of erosion.
The largest error is caused by assuming that modern sediment loads in populated areas represent natural erosion, whereas in fact they mainly reflect the influence of man. Conversion of forests to croplands in the middle Atlantic states causes about a tenfold increase in sediment yield. Coal mining, urbanization, and highway construction have added extra loads of sediment to the streams. Modern sediment loads in the Atlantic-draining rivers are probably 4 to 5 times greater than they would be if the area had remained undisturbed by man.
Errors in calculating the chemical denudation are caused by atmospheric contributions to the dissolved loads of streams and by pollutants that are added directly to stream waters. About one-quarter of the salts in Atlantic-draining streams were contributed from the atmosphere, either as recycled sea salts or as pollutants and soil dust that originally became airborne as a result of the activities of man. Perhaps another one-tenth of the dissolved load consists of industrial and agricultural wastes or acid mine waters that have been added directly to the streams.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1969)80[1265:EIUMSD]2.0.CO;2","usgsCitation":"Meade, R.H., 1969, Errors in using modern stream-load data to estimate natural rates of denudation: Geological Society of America Bulletin, v. 80, no. 7, p. 1265-1274, https://doi.org/10.1130/0016-7606(1969)80[1265:EIUMSD]2.0.CO;2.","productDescription":"10 p.","startPage":"1265","endPage":"1274","costCenters":[],"links":[{"id":389966,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Connecticut, Delaware, Georgia, Maryland, Massachusetts, New Hampshire, New Jersey, North Carolina, Pennsylvania, Rhode Island, South Carolina, Virginia, West Virginia","city":"Baltimore, Washington D.C.","otherGeospatial":"Atlantic Ocean, Appalachia, Brandywine Creek, Chesapeake Bay, Gunpowder Falls River, Lehigh River, Passaic River, Potomac River, Schuylkill River, Susquehanna River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -81.34277343749999,\n 30.524413269923986\n ],\n [\n -76.48681640625,\n 34.56085936708384\n ],\n [\n -75.03662109375,\n 35.96022296929667\n ],\n [\n -75.8056640625,\n 37.10776507118514\n ],\n [\n -73.89404296875,\n 39.99395569397331\n ],\n [\n -73.89404296875,\n 40.44694705960048\n ],\n [\n -69.9169921875,\n 41.04621681452063\n ],\n [\n -69.54345703125,\n 42.00032514831621\n ],\n [\n -70.59814453125,\n 42.407234661551875\n ],\n [\n -70.07080078125,\n 43.644025847699496\n ],\n [\n -71.54296874999999,\n 45.02695045318546\n ],\n [\n -73.23486328124999,\n 45.02695045318546\n ],\n [\n -75.47607421875,\n 42.09822241118974\n ],\n [\n -80.70556640625,\n 42.309815415686664\n ],\n [\n -80.9033203125,\n 40.04443758460856\n ],\n [\n -82.63916015625,\n 38.66835610151506\n ],\n [\n -82.705078125,\n 38.13455657705411\n ],\n [\n -81.7108154296875,\n 36.61552763134925\n ],\n [\n -82.7325439453125,\n 36.071302299422406\n ],\n [\n -83.8751220703125,\n 35.585851593232356\n ],\n [\n -84.342041015625,\n 35.25459097465022\n ],\n [\n -84.3585205078125,\n 35.02999636902566\n ],\n [\n -85.84716796875,\n 34.994003757575776\n ],\n [\n -85.18798828125,\n 31.052933985705163\n ],\n [\n -84.9462890625,\n 30.619004797647808\n ],\n [\n -81.34277343749999,\n 30.524413269923986\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"80","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Meade, Robert H. 0000-0002-4965-3040 rhmeade@usgs.gov","orcid":"https://orcid.org/0000-0002-4965-3040","contributorId":2744,"corporation":false,"usgs":true,"family":"Meade","given":"Robert","email":"rhmeade@usgs.gov","middleInitial":"H.","affiliations":[{"id":5044,"text":"National Research Program - Central Branch","active":true,"usgs":true}],"preferred":true,"id":824242,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70224269,"text":"70224269 - 1969 - Model for simulation of residual stress in rock","interactions":[],"lastModifiedDate":"2021-09-17T14:49:11.368726","indexId":"70224269","displayToPublicDate":"1969-06-16T10:20:22","publicationYear":"1969","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Model for simulation of residual stress in rock","docAbstract":"Rocks in mines, quarries, and many outcrops commonly show evidence of being under high stress. Saw cuts and drillholes close in, partly mined coal bursts violently, and pillars crush and rock spalls in mines even at moderate depths. Similarly, strong and massive rocks such as granite and sandstone naturally divide themselves into sheets that lie more or less parallel to their outward topographic form. The sheets may be either convex or concave. Thin plates of bare rock surfaces bow up and buckle. Such effects often cannot be explained by the obvious loads now acting on the rock, that is, by loads resulting from overburden, topographic irregularities, or stress concentration around openings. The stresses exceed those that would result from such loads.
Two interpretations of such excess stresses have been made. In one, the stresses are assigned in origin to now active tectonic forces. In the other, they are regarded as leftover and locked in from some previous state at which higher pressures prevailed. These two sources may both operate and they generally cannot be distinguished easily in the field. There are other complicating sources of stress such as temperature gradients and chemical alteration. Nevertheless, some bodies of rock, by exfoliating, show evidence of high internal stress even though they are practically unweathered and so isolated topographically that the presence in them of significant stress due to exterior loads or active tectonic forces seems unlikely.
Moreover, completely isolated rocks are known to change density shape, or size; to expand under constant compressive stress; and even to disintegrate without the intervention of weathering processes. The stresses involved here must be truly residual in the sense long used by metallurgists; that is, residual stresses in a body are those that remain, aside from the effect of gravity or temperature gradients, even after the boundaries are freed from loads. Residual stress within rock can exist only in a system of internally balanced forces. The existence of such balanced forces has been recognized for a long time--at least 180 years--to judge from an incomplete survey of the literature. Discussions have been presented more recently by Voight, Friedman, Emery, Price, Denkhaus, Kieslinger, and other engineers and geologists.
Briefly, a simple version of the concept is that if a granite crystallizes at depth and is then unloaded by uplift and erosion, the compressed mineral grains cannot completely relax, owing to interlocking boundaries and mutual interference. A sandstone that becomes cemented while constituent grains are under high pressure cannot completely relax when cut free. Thus, a balance is achieved between forces of expansion in the interior of the crystalline grains and those of restraint at grain boundaries or in the cement.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Proceedings of the 11th U.S. Symposium on Rock Mechanics (USRMS)","largerWorkSubtype":{"id":12,"text":"Conference publication"},"conferenceTitle":"The 11th U.S. Symposium on Rock Mechanics (USRMS)","conferenceDate":"June 16-19 1969","conferenceLocation":"Berkeley, CA","language":"English","publisher":"American Rock Mechanics Association","usgsCitation":"Varnes, D.J., 1969, Model for simulation of residual stress in rock, in Proceedings of the 11th U.S. Symposium on Rock Mechanics (USRMS), Berkeley, CA, June 16-19 1969, p. 415-426.","productDescription":"ARMA-69-0415, 12 p.","startPage":"415","endPage":"426","costCenters":[],"links":[{"id":389390,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":389347,"rank":1,"type":{"id":15,"text":"Index Page"},"url":"https://www.armarocks.org/","description":"Index Page"}],"noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Varnes, D. J.","contributorId":85201,"corporation":false,"usgs":true,"family":"Varnes","given":"D.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":823416,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70223839,"text":"70223839 - 1969 - Seismic-refraction measurements in Jackson Hole, Wyoming","interactions":[],"lastModifiedDate":"2021-09-09T20:12:56.761072","indexId":"70223839","displayToPublicDate":"1969-06-01T14:54:49","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Seismic-refraction measurements in Jackson Hole, Wyoming","docAbstract":"Three reversed seismic-refraction profiles were recorded in the Jackson Hole, Wyoming, area during July 1964. The seismic model which was developed consists of three layers with velocities of 2.4 km/sec for Tertiary and Cretaceous rocks above the Cleverly Formation (Lower Cretaceous), 3.8 km/sec for rocks from Lower Cretaceous down to lower Paleozoic, and 6.1 km/sec for lower Paleozoic (limestones and dolomites) and Precambrian rocks. The maximum thickness of sediments in Jackson Hole is 5 km, and the minimum throw of the Teton fault in the area covered by this survey is about 7 km.
","language":"English","publisher":"The Geological Society of America","doi":"10.1130/0016-7606(1969)80[1109:SMIJHW]2.0.CO;2","usgsCitation":"Tibbetts, B.L., Behrendt, J.C., and Love, J.D., 1969, Seismic-refraction measurements in Jackson Hole, Wyoming: Geological Society of America Bulletin, v. 80, no. 6, p. 1109-1121, https://doi.org/10.1130/0016-7606(1969)80[1109:SMIJHW]2.0.CO;2.","productDescription":"13 p.","startPage":"1109","endPage":"1121","costCenters":[],"links":[{"id":389026,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Wyoming","city":"Jackson Hole","otherGeospatial":"Grand Teton National Park, Rocky Mountains","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -110.88775634765625,\n 43.454912713790264\n ],\n [\n -110.70373535156249,\n 43.450925007583706\n ],\n [\n -110.50048828124999,\n 43.89195472686543\n ],\n [\n -110.6982421875,\n 43.95130472827632\n ],\n [\n -110.94543457031249,\n 43.49975628978046\n ],\n [\n -110.88775634765625,\n 43.454912713790264\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"80","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Tibbetts, B. L.","contributorId":77536,"corporation":false,"usgs":true,"family":"Tibbetts","given":"B.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":822888,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Behrendt, J. C.","contributorId":190262,"corporation":false,"usgs":false,"family":"Behrendt","given":"J.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":822889,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Love, John David","contributorId":39869,"corporation":false,"usgs":true,"family":"Love","given":"John","email":"","middleInitial":"David","affiliations":[],"preferred":false,"id":822890,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70206573,"text":"70206573 - 1969 - New thrusts in ground water","interactions":[],"lastModifiedDate":"2022-11-22T17:18:07.819422","indexId":"70206573","displayToPublicDate":"1969-03-31T09:05:39","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3825,"text":"Groundwater","active":true,"publicationSubtype":{"id":10}},"title":"New thrusts in ground water","docAbstract":"Four principal trends in ground water are apparent:
(1) Increasing use of ground water for domestic supplies. Geohydrologists must learn to quantitatively evaluate the supply under conditions of maximum development, not merely determine the availability of a supply that does not strain the aquifer. (2) Aquifers will be looked to increasingly as possible storage media for surplus flood water, in place of dams and reservoirs. The key here is economics – optimum utilization of resources. The job of the geohydrologist is to do enough research and experimentation to determine when, where, and how ground-water reservoirs can be recharged artificially at a reasonable cost. (3) Saline aquifers will be looked at as sources of water supply. The cost curves of developing new supplies of fresh water are ascending while the cost curves for desalinization are declining, and inevitably they will cross in one area after another. There is a paucity of information on saline ground-water aquifers; hence, the utmost skill must be used in evaluating the resource. (4) With efforts to prevent stream pollution, aquifers will be looked to increasingly as possible storage media for industrial and domestic waste effluents. Control is urgently needed so the effects of waste injection can be predicted, the technology for confining those effects as intended can be developed, and a basis can be provided for a rational decision as to whether waste injection or an alternative use of the chosen aquifer is best for the economy in the long run. However, there is little legal basis for control, and the cost of such control may make the practice unfeasible in many situations.
A systems-analysis approach is needed to develop a working model of a given hydrologie and socio-economic problem from which quantitative answers can be given to water planners.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1745-6584.1969.tb01269.x","usgsCitation":"McGuinness, C.L., 1969, New thrusts in ground water: Groundwater, v. 7, no. 2, p. 7-10, https://doi.org/10.1111/j.1745-6584.1969.tb01269.x.","productDescription":"4 p.","startPage":"7","endPage":"10","costCenters":[],"links":[{"id":369103,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"7","issue":"2","noUsgsAuthors":false,"publicationDate":"2006-07-06","publicationStatus":"PW","contributors":{"authors":[{"text":"McGuinness, C. L.","contributorId":20313,"corporation":false,"usgs":true,"family":"McGuinness","given":"C.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":775026,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70169094,"text":"70169094 - 1969 - Heat flow in the Arctic","interactions":[],"lastModifiedDate":"2016-03-17T11:12:16","indexId":"70169094","displayToPublicDate":"1969-03-01T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":894,"text":"Arctic","active":true,"publicationSubtype":{"id":10}},"title":"Heat flow in the Arctic","docAbstract":"","language":"English","publisher":"Arctic Institute of North America","doi":"10.14430/arctic3221","usgsCitation":"Lachenbruch, A.H., and Marshall, B.V., 1969, Heat flow in the Arctic: Arctic, v. 22, no. 3, p. 300-311, https://doi.org/10.14430/arctic3221.","productDescription":"12 p.","startPage":"300","endPage":"311","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[],"links":[{"id":480310,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.14430/arctic3221","text":"Publisher Index Page"},{"id":318935,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Arctic","volume":"22","issue":"3","noUsgsAuthors":false,"publicationDate":"1969-01-01","publicationStatus":"PW","scienceBaseUri":"56ebd530e4b0f59b85da065d","contributors":{"authors":[{"text":"Lachenbruch, Arthur H.","contributorId":27850,"corporation":false,"usgs":true,"family":"Lachenbruch","given":"Arthur","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":622905,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Marshall, B. Vaughan","contributorId":83896,"corporation":false,"usgs":true,"family":"Marshall","given":"B.","email":"","middleInitial":"Vaughan","affiliations":[],"preferred":false,"id":622906,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70010090,"text":"70010090 - 1969 - Florida submergence curve revised: Its relation to coastal sedimentation rates","interactions":[],"lastModifiedDate":"2026-02-04T17:26:28.260358","indexId":"70010090","displayToPublicDate":"1969-02-07T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3338,"text":"Science","active":true,"publicationSubtype":{"id":10}},"title":"Florida submergence curve revised: Its relation to coastal sedimentation rates","docAbstract":"New data substantiate as well as modify the south Florida submergence curve, which indicates that eustatic sea level has risen continuously, although at a generally decreasing rate, during the last 6500 to 7000 sidereal years (5500 standard radiocarbon years) to reach its present position. Accumulation rates of coastal deposits are similar to the rate of sea-level rise, thus supporting the generalization that submergence rates largely determine as well as limit rates of coastal sedimentation in lagoonal and estuarine areas.","language":"English","publisher":"American Association for the Advancement of Science","doi":"10.1126/science.163.3867.562","issn":"00368075","usgsCitation":"Scholl, D., Craighead, F., and Stuiver, M., 1969, Florida submergence curve revised: Its relation to coastal sedimentation rates: Science, v. 163, no. 3867, p. 562-564, https://doi.org/10.1126/science.163.3867.562.","productDescription":"3 p.","startPage":"562","endPage":"564","costCenters":[],"links":[{"id":219590,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"south Florida","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -82.81485249420433,\n 28.695319216051175\n ],\n [\n -82.81485249420433,\n 24.902227860305473\n ],\n [\n -79.00007154825742,\n 24.902227860305473\n ],\n [\n -79.00007154825742,\n 28.695319216051175\n ],\n [\n -82.81485249420433,\n 28.695319216051175\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"163","issue":"3867","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a122ee4b0c8380cd541ee","contributors":{"authors":[{"text":"Scholl, D.W.","contributorId":106461,"corporation":false,"usgs":true,"family":"Scholl","given":"D.W.","email":"","affiliations":[],"preferred":false,"id":357875,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Craighead, F.C. Sr.","contributorId":91985,"corporation":false,"usgs":true,"family":"Craighead","given":"F.C.","suffix":"Sr.","email":"","affiliations":[],"preferred":false,"id":357874,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Stuiver, M.","contributorId":54730,"corporation":false,"usgs":true,"family":"Stuiver","given":"M.","affiliations":[],"preferred":false,"id":357873,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70224268,"text":"70224268 - 1969 - A seismic-refraction survey of crustal structure in central Arizona","interactions":[],"lastModifiedDate":"2021-09-16T15:00:30.408014","indexId":"70224268","displayToPublicDate":"1969-02-01T09:46:23","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1786,"text":"Geological Society of America Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"A seismic-refraction survey of crustal structure in central Arizona","docAbstract":"
The U.S. Geological Survey conducted a seismic-refraction study of the earth's crust and upper mantle near the Tonto Forest Seismological Observatory (TFO), located 10miles south of the Mogollon Rim near Payson in central Arizona. Two recording lines 400 km long intersect in the approximate form of a cross at TFO; one line trends southeast and the other northeast. The sedimentary layer at most places southwest of the rim is less than 1 km thick, but north of the rim it is 2 to 3 km thick. The velocity in this uppermost layer ranges from 2.6 to 4.7 km/sec, with the higher limit measured near or north of the rim. Arrivals refracted in the upper crust (Pg) can be attributed to two layers for all the shot points south of the rim. The velocity in the upper layer is about 5.9 km/sec with thickness ranging from 2 to 8 km; beneath the upper layer the velocity is about 6.1 km/sec. The upper layer seems to be absent northeast of the rim, where two shot points generated Pg arrivals that show only a velocity of 6.2 km/sec. A Poisson ratio of 0.22 for the upper crustal layers was measured from shear and compressional arrivals. The lower crust could not be identified from the first and later refraction arrivals; however, minimum depths to the intermediate layer were determined. An average crustal velocity of 6.2 km/sec was measured from wide-angle reflection alignments. A thin intermediate layer would explain the seismic measurements.
A delay-time method was used to map the configuration of the M-discontinuity. The depth below sea level is about 36 km along the northwest-trending line. The northeast-trending line shows a shallow depth of 21 km near Gila Bend, increasing depth to about 34 km under TFO, and a flat M-discontinuity at 40 km depth under the Mogollon Mesa northeast to Sunrise Springs. There is evidence of an abrupt depth change of about 4 km on the M-discontinuity in the vicinity of TFO. The velocity in the upper mantle is 7.85 km/sec. The relation of topographic elevation to crustal thickness suggests an approach to isostatic equilibrium, which is deduced from a near-zero regional free-air gravity anomaly. However, lateral density change in the upper mantle is required to make the crustal-refraction model fit the observed gravity-anomaly values, provided that velocity and density are linearly related.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/0016-7606(1969)80[257:ASSOCS]2.0.CO;2","usgsCitation":"Warren, D.H., 1969, A seismic-refraction survey of crustal structure in central Arizona: Geological Society of America Bulletin, v. 80, no. 2, p. 257-282, https://doi.org/10.1130/0016-7606(1969)80[257:ASSOCS]2.0.CO;2.","productDescription":"26 p.","startPage":"257","endPage":"282","costCenters":[],"links":[{"id":389345,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona","city":"Payson","otherGeospatial":"Gila Bend, Mogollon Mesa, Mogollon Rim, Sunrise Springs, Tonto Forest Seismological Observatory","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -110.028076171875,\n 32.62087018318113\n ],\n [\n -109.4732666015625,\n 35.808904044068626\n ],\n [\n -113.69750976562499,\n 36.02244668175846\n ],\n [\n -113.45581054687499,\n 32.491230287947594\n ],\n [\n -110.028076171875,\n 32.62087018318113\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"80","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Warren, David H.","contributorId":106128,"corporation":false,"usgs":true,"family":"Warren","given":"David","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":823415,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70207923,"text":"70207923 - 1969 - Volcanic substructure inferred from dredge samples and ocean-bottom photographs, Hawaii","interactions":[],"lastModifiedDate":"2020-01-20T12:52:06","indexId":"70207923","displayToPublicDate":"1969-01-20T12:51:58","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1723,"text":"GSA Bulletin","active":true,"publicationSubtype":{"id":10}},"title":"Volcanic substructure inferred from dredge samples and ocean-bottom photographs, Hawaii","docAbstract":"Ocean-bottom photographs from 18 stations and dredge hauls from 35 stations adjacent to the Island of Hawaii indicate that basaltic pillow lava and pillow fragments are the dominant rock type on the crest and flanks of the submarine rift zone ridges, whereas glassy basalt sand and scoria are the dominant type on the submarine flanks of the volcanoes directly downslope from land. These relations indicate that three major rock units comprise different levels of the volcanoes depending on the site of eruption: (1) pillow lavas and pillow fragments are dominant below sea level and are erupted from deep-water vents; (2) hyaloclastite rocks (vitric explosion debris, littoral cone ash, and flow-foot breccias) mantle the pillowed base of the volcano, and are erupted from shallow-water vents, subaerial vents in water-soaked ground, or are produced where subaerial lava flows cross the shoreline; and (3) thin subaerial lava flows make up the visible, subaerial shield volcano, are built atop the clastic layer, and are erupted from subaerial vents. This three-fold structure is similar to the table mountains of Iceland that are built by eruption beneath glacial ice.
Large-scale slumping in the clastic layer may modify the submarine slopes of the volcanoes as well as produce faulting and downslope movement of parts of the overlying shield volcano. The slope change produced where the gentler shield meets the steeper pillowed pile can be recognized beneath sea level in the older volcanoes, where it has been submerged by regional subsidence.
","language":"English","publisher":"GSA","doi":"10.1130/0016-7606(1969)80[1191:VSIFDS]2.0.CO;2","usgsCitation":"Moore, J.G., and Fiske, R.S., 1969, Volcanic substructure inferred from dredge samples and ocean-bottom photographs, Hawaii: GSA Bulletin, v. 80, no. 7, p. 1191-1202, https://doi.org/10.1130/0016-7606(1969)80[1191:VSIFDS]2.0.CO;2.","productDescription":"12 p.","startPage":"1191","endPage":"1202","costCenters":[{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"links":[{"id":371376,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Hawaii","otherGeospatial":"Kilauea Volcano","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -155.82733154296875,\n 18.781516724349704\n ],\n [\n -154.654541015625,\n 18.781516724349704\n ],\n [\n -154.654541015625,\n 20.017226126835062\n ],\n [\n -155.82733154296875,\n 20.017226126835062\n ],\n [\n -155.82733154296875,\n 18.781516724349704\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"80","issue":"7","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Moore, James G. 0000-0002-7543-2401 jmoore@usgs.gov","orcid":"https://orcid.org/0000-0002-7543-2401","contributorId":2892,"corporation":false,"usgs":true,"family":"Moore","given":"James","email":"jmoore@usgs.gov","middleInitial":"G.","affiliations":[{"id":114,"text":"Alaska Science Center","active":true,"usgs":true},{"id":617,"text":"Volcano Science Center","active":true,"usgs":true}],"preferred":true,"id":779783,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Fiske, Richard S.","contributorId":17984,"corporation":false,"usgs":true,"family":"Fiske","given":"Richard","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":779784,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70225579,"text":"70225579 - 1969 - Geology and regional metamorphism of some high-grade cordierite gneisses, Front Range, Colorado","interactions":[],"lastModifiedDate":"2021-10-25T20:11:16.590613","indexId":"70225579","displayToPublicDate":"1969-01-01T14:57:36","publicationYear":"1969","noYear":false,"publicationType":{"id":4,"text":"Book"},"publicationSubtype":{"id":15,"text":"Monograph"},"seriesTitle":{"id":5985,"text":"Special Papers of the Geological Society of America","active":true,"publicationSubtype":{"id":15}},"title":"Geology and regional metamorphism of some high-grade cordierite gneisses, Front Range, Colorado","docAbstract":"Cordierite is common in regional metamorphic gneisses of Precambrian age in the central part of the Front Range. It occurs in discontinuous stratigraphic units that are structurally a minor component, except locally, of the thick succession of biotite gneisses that comprise the widespread Idaho Springs Formation. The rocks have mineral assemblages, that are characteristic of the sillimanite grade of metamorphism.
The cordierite occurs in three principal rock types: (1) potassic feldspar-bearing cordierite-garnet-sillimanite-biotite gneiss, (2) cordierite-biotite gneiss, and (3) cordierite-gedrite-biotite gneiss; each type contains several characteristic mineral assemblages. The rock types are gradational and overlap in areal distribution, and mainly owe their diversity in mineralogy to differences in bulk chemical composition. The field relations are consistent with an interpretation that the diverse cordierite rocks were derived from original sedimentary rocks, largely pelitic sediments. The potassic feldspar-bearing cordierite-garnet gneisses were formed from shales that contained more MgO and FeO than the more abundant sedimentary facies that yielded sillimanitic biotite gneisses. Cordierite-gedrite-biotite gneisses contain much aluminum, iron, and magnesium and little sodium and potassium as compared to the other biotite gneisses; they have an extremely low content of minor elements. Although their chemical compositions are unlike those of known modern sediments, the cordierite-gedrite gneisses are considered also to have been derived from sedimentary rocks.
The physical properties and chemical compositions of the mineral phases vary somewhat from one rock type to another. Biotite varies systematically in composition, and the changes are closely related to rock type and thus to bulk composition; the MgO/FeO ratios range from 1.7 in the more mafic cordierite-gedrite rocks to 0.49 in potassic feldspar-bearing cordierite-garnet gneisses. Cordierite is magnesium-rich and intermediate in the range of composition of all analyzed cordierites (Leake, 1960); its MgO/FeO ratio is higher in the gedrite-bearing gneisses than in the potassic feldspar-bearing gneisses. The garnets consist dominantly of the almandine and pyrope molecules, and range from 64 to 75 percent almandine and from 14 to 27 pyrope. These crystals are zoned; their rims are slightly more ferrous and less magnesian than their cores. Both monoclinic and triclinic alkali feldspars coexist in the potassic feldspar-bearing cordierite-garnet gneisses. The potassic feldspars contain from 18 to 27 weight percent NaAlSi3O8. Plagioclase (oligoclase-andesine) is uncommon in the rocks. Gedrite has an MgO/FeO ratio ranging from 1 to 1.2. Associated minor minerals include iron oxides, andalusite, spinel and its alteration product högbomite, and corundum.
The mineral assemblages can be correlated imperfectly with episodes of deformation and metamorphism. Relict staurolite and associated garnet occur locally as remnants of an assemblage formed early in regional metamorphism, presumably early in the first period of deformation. The dominant assemblage biotite-cordierite-garnet-magnetite-plagioclase-potassic feldspar-quartz-sillimanite and associated assemblages having fewer phases, were formed during period one and period two deformations, the principal episodes of regional dynamothermal metamorphism in the central part of the Front Range. A minor assemblage andalusite-biotite-magnetite-plagioclase-quartz was formed later, possibly coincident with a third period of deformation, largely cataclastic in effects, which was more local than the earlier deformations and metamorphism.
Phase equilibria studies of the assemblage biotite-cordierite-garnet-magnetite-plagioclase-potassic feldspar-quartz-sillimanite and associated assemblages are interpreted to indicate that the cordierite assemblages approach a state of chemical equilibrium. The scatter of points in a distribution diagram can be interpreted in terms of at least two sets of equilibrium conditions that prevailed during the major plastic deformations. Other discrepancies indicating departure from a homogeneous equilibrium can be explained as a result of mosaic equilibrium involving limited diffusion of iron and magnesium for short distances.
The mineral assemblages and the compositions of the ferromagnesian minerals in the cordierite rocks of this region are dependent primarily on the bulk composition of the rocks and variations in the mineral species that comprise the rocks and, to a lesser degree, on the grade of metamorphism. Biotite and cordierite are markedly more magnesian in the more mafic cordierite-gedrite-biotite gneiss than in the potassic feldspar-bearing cordierite-garnet-sillimanite-biotite gneiss.
Associated microcline gneiss and biotite-sillimanite gneiss that contains muscovite as a primary stable mineral provides a means to define the metamorphic grade in the area of study. It is concluded from analyses of the assemblages with respect to theoretical phase relations in the system SiO2-Al2O3-Na2O-K2O-H2O that at least some of the rocks in the Central City-Nederland area are above the sillimanite-potassic feldspar isograd as defined by Evans and Guidotti (1966). In rocks of appropriate composition, muscovite is a stable phase in assemblages containing potassic feldspar and sillimanite.
The cordierite assemblages and associated rocks are inferred to have formed in an environment having a load pressure of 3–5 kilobars (fluid pressure equaled load pressure) and a temperature somewhat in excess of 620° C.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/SPE128","usgsCitation":"Gable, D.J., and Sims, P., 1969, Geology and regional metamorphism of some high-grade cordierite gneisses, Front Range, Colorado: Special Papers of the Geological Society of America, v. 128, 85 p., https://doi.org/10.1130/SPE128.","productDescription":"85 p.","startPage":"1","endPage":"84","costCenters":[],"links":[{"id":480311,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1130/spe128","text":"Publisher Index Page"},{"id":390908,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","otherGeospatial":"Front Range","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -106.512451171875,\n 38.59970036588819\n ],\n [\n -104.612060546875,\n 38.59970036588819\n ],\n [\n -104.612060546875,\n 41.017210578228436\n ],\n [\n -106.512451171875,\n 41.017210578228436\n ],\n [\n -106.512451171875,\n 38.59970036588819\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"128","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Gable, Dolores J.","contributorId":52957,"corporation":false,"usgs":true,"family":"Gable","given":"Dolores","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":825664,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Sims, Paul K.","contributorId":67852,"corporation":false,"usgs":true,"family":"Sims","given":"Paul K.","affiliations":[],"preferred":false,"id":825665,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70225578,"text":"70225578 - 1969 - History of the Redwall Limestone of northern Arizona","interactions":[],"lastModifiedDate":"2022-11-21T18:01:35.023539","indexId":"70225578","displayToPublicDate":"1969-01-01T14:27:35","publicationYear":"1969","noYear":false,"publicationType":{"id":4,"text":"Book"},"publicationSubtype":{"id":15,"text":"Monograph"},"title":"History of the Redwall Limestone of northern Arizona","docAbstract":"Throughout most of northern Arizona the Redwall Limestone of Mississippian age is readily divisible into four lithologic units, designated in ascending order as the Whitmore Wash, Thunder Springs, Mooney Falls, and Horseshoe Mesa Members. The first and third members are thick-bedded to massive carbonate rock. The Horseshoe Mesa Member is relatively thin-bedded limestone, and the Thunder Springs Member is distinctive because it consists of chert beds alternating with thin beds of carbonate rock.
Trends in thickness of the various members indicate that the sediment that formed the Redwall was deposited on an even, gently sloping shelf that extended westward from the Defiance positive element, a low landmass located near the present eastern border of northern Arizona. The Peach Springs and Payson ridges projected west and southwest, respectively, from the positive element. These ridges, which were partly submerged and partly above sea level during Mississippian time, are indicated by the patterns of isopach lines and, in part, by the distribution of faunas. The ridges divided the Arizona section of the shelf into three segments: the northern-most, which slopes northwest toward the Cordilleran geosyncline, and the other two, which slope toward the south and southwest.
Two transgressions and two regressions of the western and southern seaways are believed to be represented by the Redwall. The first transgression, which is recorded by thick beds of clastic sediment of the Whitmore Wash Member, was less extensive than the second, which is recorded by massive beds of the Mooney Falls Member, for on the western margins of the Defiance positive element the Mooney Falls Member overlaps the two lower members. Furthermore, south of Grand Canyon the Whitmore Wash and Thunder Springs Members lap against the Payson ridge without covering it, whereas the Mooney Falls Member, although relatively thin, extends across it. Regression is believed to be represented by thin beds of the Thunder Springs and Horseshoe Mesa Members, which are interpreted to be the result of low base level caused by silting up with clastic material and consequent retreat of the sea.
Cycles in sedimentation are well developed in some parts of the Redwall, especially in the upper two members in which differences in grain size represent five major cycles recognized throughout the extent of the Grand Canyon. These textural differences, ranging from aphanitic to coarse grained, are considered to be not measures of the amount of transportation, as with terrigenous sediments, but reflections of the degree of turbulence or the lack of turbulence during deposition.
They are interpreted as indicators of cyclic fluctuations in environment, probably related to changes in wave base.
Several clearly defined facies within the Redwall indicate environments of deposition. The clastic limestone that forms a major part of the formation, especially in the offshore areas to the west and south, is believed to represent normal marine conditions where circulation was good and turbulence moderate to strong. Uniform finely crystalline dolomite probably developed through early diagenetic processes on the sea floor. On the basis of its distribution pattern the dolomite seems to have formed under shoal conditions, especially where it borders the shore of the Defiance positive element and along Peach Springs ridge. Oölitic limestone at the top of both major transgressive units is interpreted as reflecting the oscillatory conditions of sea level that provided wave and current agitation at times of maximum sea advance in shoal areas bordering the ridges. Aphanitic limestone, representing accumulations of lime mud, seems to be developed best in the uppermost, or Horseshoe Mesa, member, where, as the seas regressed, nearshore waters may have been isolated and certainly were very calm.
Original textures and some structures are preserved in most limestones of the Redwall, and they give much evidence concerning oceanographic factors of the time. Generalizations have been developed concerning the character of the bottom, degrees of energy represented, depth, salinity, and other factors for various parts of the formation. Although these factors differed greatly with time and space, the general conclusions reached are that (1) depths were very shallow to moderate, (2) the sea floor was composed nearly entirely of lime mud and lime sand, which contained no terrigeneous material but with great crinoidal accumulations locally, (3) turbulence ranged from considerable to none, and (4) the sea was clear and warm and nowhere contained saline concentrations sufficient to form evaporites.
Chert forming thin irregular beds, locally lenticular and nodular, occurs at two prinicpal positions in the stratigraphic section, and in each it alternates with thin beds of carbonate rock. Chert is prominent throughout the Thunder Springs Member and forms thin but definite zones near the top of the Mooney Falls Member. This chert is believed to have formed on the sea floor during early diagenesis, as evidenced by petrography, paleogeography, and faunal relations. Regional differences in the abundance and type of associated fossils, recorded on a series of 4-foot-square sample plots made throughout the Grand Canyon, suggest a probable relation between fossil distribution and genesis of the chert.
The fauna of the Redwall is abundant and varied, but preservation in many places is poor, and numerous specimens can be collected only locally. The most common fossils are brachiopods, corals, foraminifers, and crinoids, but blastoids, gastropods, cephalopods, and pelecypods are not rare. Bryozoans are abundant in the chert of the Thunder Springs Member but uncommon elsewhere. Other organisms locally distributed but not common are algae, trilobites, fish, holothurians, and ostracodes. These groups have been studied by specialists and are the subject of Chapters V through XIII.
Certain of the faunal groups, notably the corals and foraminifers, show some degree of vertical zoning and so have furnished important data on age and correlation. Among the corals, the zones of Dorlodotia inconstans and Michelinia expansa are especially significant because of their persistence from section to section across broad areas. The foraminiferal zones are broader and less sharply defined, but they represent a series of major changes in species from bottom to top of the formation.
Age determination made on the basis of foraminifers and brachiopods indicate that the base of the Redwall is progressively younger as it passes from areas that were offshore eastward or northward toward the Defiance positive element; the top of the Redwall, in contrast, is shown to be progressively younger away from the positive element. Thus basal beds of Kinderhook age are recognized at Grand Wash, Quartermaster, and Meriwitica Canyons to the northwest, but the lowest strata are of Osage age at Bridge Canyon, Grandview, and other sections closer to the landmass. Likewise, units with fossils of middle Meramec age occur in western Grand Canyon, but, except in the one place discussed in the following paragraph, topmost beds farther east in Grand Canyon are of Osage age. South of Grand Canyon the youngest member of the Redwall (Horseshoe Mesa) has been removed by pre-Supai Formation erosion.
Rocks still younger than the Horseshoe Mesa once may have covered the entire region, possibly representing a third sequence of transgression and regression. At Bright Angel trail in eastern Grand Canyon, for example, a unique unit at the top of the Redwall section contains fossils of Chester age and apparently represents a remnant of Late Mississippian rocks that survived as an inlier there.
","language":"English","publisher":"Geological Society of America","doi":"10.1130/MEM114","usgsCitation":"McKee, E.D., and Gutschick, R.C., 1969, History of the Redwall Limestone of northern Arizona, v. 114, 700 p., https://doi.org/10.1130/MEM114.","productDescription":"700 p.","costCenters":[],"links":[{"id":480312,"rank":0,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1130/mem114","text":"Publisher Index Page"},{"id":390903,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Arizona","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -114.488525390625,\n 34.07996230865873\n ],\n [\n -109.00634765625,\n 34.07086232376631\n ],\n [\n -109.00634765625,\n 37.02886944696474\n ],\n [\n -114.08203125,\n 37.020098201368114\n ],\n [\n -114.10400390625,\n 36.32397712011264\n ],\n [\n -114.2138671875,\n 36.06686213257888\n ],\n [\n -114.3896484375,\n 36.24427318493909\n ],\n [\n -114.774169921875,\n 36.10237644873644\n ],\n [\n -114.7412109375,\n 35.567980458012094\n ],\n [\n -114.7412109375,\n 35.40696093270201\n ],\n [\n -114.63134765625001,\n 35.200744801724014\n ],\n [\n -114.7412109375,\n 35.110921809704756\n ],\n [\n -114.7412109375,\n 34.813803317113155\n ],\n [\n -114.488525390625,\n 34.542762387234845\n ],\n [\n -114.466552734375,\n 34.415973384481866\n ],\n [\n -114.202880859375,\n 34.279914398549934\n ],\n [\n -114.488525390625,\n 34.07996230865873\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"114","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"McKee, Edwin D.","contributorId":60207,"corporation":false,"usgs":true,"family":"McKee","given":"Edwin","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":825662,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gutschick, Raymond C.","contributorId":12054,"corporation":false,"usgs":true,"family":"Gutschick","given":"Raymond","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":825663,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70200394,"text":"70200394 - 1969 - The linear decision rule in reservoir management and design: 1, Development of the stochastic model","interactions":[],"lastModifiedDate":"2018-10-16T14:09:40","indexId":"70200394","displayToPublicDate":"1969-01-01T14:09:28","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3722,"text":"Water Resources Research","onlineIssn":"1944-7973","printIssn":"0043-1397","active":true,"publicationSubtype":{"id":10}},"title":"The linear decision rule in reservoir management and design: 1, Development of the stochastic model","docAbstract":"With the aid of a linear decision rule, reservoir management and design problems often can be formulated as easily solved linear programing problems. The linear decision rule specifies the release during any period of reservoir operation as the difference between the storage at the beginning of the period and a decision parameter for the period. The decision parameters for the entire study horizon are determined by solving the linear programing problem. Problems may be formulated in either the deterministic or the stochastic environment.
","language":"English","publisher":"AGU","doi":"10.1029/WR005i004p00767","usgsCitation":"Revelle, C., Joeres, E., and Kirby, W.H., 1969, The linear decision rule in reservoir management and design: 1, Development of the stochastic model: Water Resources Research, v. 5, no. 4, p. 767-777, https://doi.org/10.1029/WR005i004p00767.","productDescription":"11 p.","startPage":"767","endPage":"777","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":358403,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"5","issue":"4","noUsgsAuthors":false,"publicationDate":"2010-07-09","publicationStatus":"PW","contributors":{"authors":[{"text":"Revelle, Charles","contributorId":209744,"corporation":false,"usgs":false,"family":"Revelle","given":"Charles","email":"","affiliations":[],"preferred":false,"id":748706,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Joeres, Erhard","contributorId":209745,"corporation":false,"usgs":false,"family":"Joeres","given":"Erhard","email":"","affiliations":[],"preferred":false,"id":748707,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Kirby, William H.","contributorId":7294,"corporation":false,"usgs":true,"family":"Kirby","given":"William","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":748708,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70224277,"text":"70224277 - 1969 - Modern coastal mangrove swamp stratigraphy and the ideal cyclothem","interactions":[],"lastModifiedDate":"2021-09-17T16:39:33.710762","indexId":"70224277","displayToPublicDate":"1969-01-01T11:26:07","publicationYear":"1969","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"seriesTitle":{"id":5614,"text":"Special Papers of the Geological Society of America","printIssn":"0072-1077","active":true,"publicationSubtype":{"id":24}},"title":"Modern coastal mangrove swamp stratigraphy and the ideal cyclothem","docAbstract":"The general stratigraphy of the “ideal” cyclothem of Late Paleozoic age can be recognized in a modern succession of sedimentary units underlying the coastal mangrove swamps of southwestern Florida. Because coal deposition is associated with the formation of cyclothems, this stratigraphic similarity has geologic importance with respect to coal formation.
The lower part of the succession in Florida consists of nonmarine sediments, the middle part of brackish-water or fresh-water mangrove peat, and the upper part of brackish-water and marine units. This sequence of sediments records a relative rise in sea level. In comparison, the lower part of the ideal cyclothem consists basically of nonmarine units, the central sedimentary member is coal, and the upper units are brackish-water and marine sediments.
The ideal cyclothem is thought to have formed in part in a deltaic environment and to record a periodic fluctuation in terrigenous sediment supply and a relative rise in sea level. In contrast, southwestern Florida has essentially no deltas, as most of its paralic sediments are derived from coastal sources. In view of this, the stratigraphic similarity noted above must reflect a partial duplication of sedimentary environments brought about by a relative rise in sea level across a low coastal platform supporting peat-depositing paralic and fresh-water swamps and forests. This conclusion tends to support the point of view that the coal member of some cyclothems formed in a swampy environment penecontemporaneously with a relative rise in sea level. The coal member, therefore, is in part a transgressive unit.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Environments of coal deposition: Papers presented at a symposium by the coal geology division of the Geological Society of America at the annual meeting Miami Beach, Florida, 1964","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/SPE114-p37","usgsCitation":"Scholl, D.W., 1969, Modern coastal mangrove swamp stratigraphy and the ideal cyclothem, chap. of Environments of coal deposition: Papers presented at a symposium by the coal geology division of the Geological Society of America at the annual meeting Miami Beach, Florida, 1964: Special Papers of the Geological Society of America, v. 114, p. 37-62, https://doi.org/10.1130/SPE114-p37.","productDescription":"26 p.","startPage":"37","endPage":"62","costCenters":[],"links":[{"id":389404,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Florida","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -83.07861328125,\n 29.180941290001776\n ],\n [\n -82.97973632812499,\n 27.72243591897343\n ],\n [\n -81.27685546875,\n 24.946219074360084\n ],\n [\n -82.100830078125,\n 24.597080137096412\n ],\n [\n -81.771240234375,\n 24.297040469311558\n ],\n [\n -80.233154296875,\n 25.005972656239187\n ],\n [\n -82.5732421875,\n 29.34387539941801\n ],\n [\n -83.07861328125,\n 29.180941290001776\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"114","noUsgsAuthors":false,"publicationDate":"1969-01-01","publicationStatus":"PW","contributors":{"editors":[{"text":"Dapples, Edward C.","contributorId":265809,"corporation":false,"usgs":false,"family":"Dapples","given":"Edward","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":823438,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Hopkins, M. E.","contributorId":265810,"corporation":false,"usgs":false,"family":"Hopkins","given":"M.","email":"","middleInitial":"E.","affiliations":[],"preferred":false,"id":823439,"contributorType":{"id":2,"text":"Editors"},"rank":2}],"authors":[{"text":"Scholl, David W. 0000-0001-6500-6962 dscholl@usgs.gov","orcid":"https://orcid.org/0000-0001-6500-6962","contributorId":3738,"corporation":false,"usgs":true,"family":"Scholl","given":"David","email":"dscholl@usgs.gov","middleInitial":"W.","affiliations":[{"id":186,"text":"Coastal and Marine Geology Program","active":true,"usgs":true},{"id":520,"text":"Pacific Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":true,"id":823437,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70226141,"text":"70226141 - 1969 - Geologic Settings of Subsidence","interactions":[],"lastModifiedDate":"2021-11-12T16:26:31.571608","indexId":"70226141","displayToPublicDate":"1969-01-01T10:20:23","publicationYear":"1969","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Geologic Settings of Subsidence","docAbstract":"This paper reviews the role of geologic processes that contribute to subsidence in order to aid those starting investigations of ground-surface subsidence. Subsidence occurs, or at least is discovered, only infrequently, and little organized information has been available. In order to assess our present state of knowledge, the author gathered fragmentary bits of information from many sources widely scattered in the literature of geology and other earth sciences.
The author cites examples for each geologic process that is a potential contributor to ground-surface subsidence together with geologic evidence for diagnosing their causes. The geologic processes involved are: (1) solution of gypsum and salt and redistribution of transient fill materials through solution cavities in calcareous rocks; (2) underground erosion of uncemented or lightly cemented silt and sand through temporary underground passageways; (3) lateral plastic flow of salt, gypsum and anhydrite, shale, and clay under loading; (4) compaction of sediments by loading, drainage, vibration, and hydrocompaction; (5) tectonic movements including primary and secondary effects of earthquakes, folding, and warping; and (6) volcanic activity. Because the first four processes may be accelerated by various engineering activities, examples have been selected to illustrate subsidence both under natural conditions and under conditions modified by man's activities.
Although this extensive search for existing information on the role of geologic factors in subsidence indicates that much detailed work remains to be done, the future prospects for advancing our geologic knowledge are excellent. Methods of measuring ground-surface displacements are improving rapidly. Also, broadly based investigations of known areas of major subsidence throughout the world are developing new methods of diagnosis and treatment and are yielding quantitative data that will aid our evaluation of the rates and magnitude of present-day geologic processes.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Reviews in Engineering Geology","largerWorkSubtype":{"id":15,"text":"Monograph"},"language":"English","publisher":"Geological Society of America","doi":"10.1130/REG2-p305","usgsCitation":"Allen, A.S., 1969, Geologic Settings of Subsidence, chap. of Reviews in Engineering Geology, v. 2, p. 305-342, https://doi.org/10.1130/REG2-p305.","productDescription":"42 p.","startPage":"305","endPage":"342","costCenters":[],"links":[{"id":391615,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"editors":[{"text":"Varnes, David J.","contributorId":86322,"corporation":false,"usgs":true,"family":"Varnes","given":"David J.","affiliations":[],"preferred":false,"id":826626,"contributorType":{"id":2,"text":"Editors"},"rank":1},{"text":"Kiersch, George","contributorId":267948,"corporation":false,"usgs":false,"family":"Kiersch","given":"George","email":"","affiliations":[],"preferred":false,"id":826627,"contributorType":{"id":2,"text":"Editors"},"rank":2}],"authors":[{"text":"Allen, Alice S.","contributorId":268784,"corporation":false,"usgs":false,"family":"Allen","given":"Alice","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":826625,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70011507,"text":"70011507 - 1969 - A paleomagnetic study of secular variation in New Zealand","interactions":[],"lastModifiedDate":"2020-11-29T18:07:51.155521","indexId":"70011507","displayToPublicDate":"1969-01-01T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1427,"text":"Earth and Planetary Science Letters","active":true,"publicationSubtype":{"id":10}},"title":"A paleomagnetic study of secular variation in New Zealand","docAbstract":"Ancient secular variation in New Zealand was determined from paleomagnetic measurements on 22 volcanic formations with ages of less than 0.68 m.y. The angular standard deviation from the field of an axial dipole is 13.2° with 95% confidence limits between 10.9° and 16.7°. The angular standard deviation of the corresponding virtual geomagnetic poles is 19.6° with confidence limits between 16.2° and 24.7°. These values are larger than those predicted by most models for secular variation. No difference was detected between the angular secular variation in New Zealand and that at the same latitude in North America.
Over 3 500 measurements of surface heat-flux have been catalogued and analyzed to study the large-scale variations of terrestrial heat-flow. It was found that heat-flow values are correlated with major geologic provinces: higher averages and scattered values in active tectonic regions, and lower averages and more uniform values in stable areas. Analyzing the data in the light of new global tectonics shows that the variations of heat-flow are consistent with the hypotheses of sea-floor spreading and plate tectonics. The observed heat-flow across the mid-oceanic ridges can be accounted for by a simple model of a spreading sea floor.
","language":"English","publisher":"Elsevier","doi":"10.1016/0031-9201(69)90026-0","issn":"00319201","usgsCitation":"Lee, W., 1969, On the global variations of terrestrial heat-flow: Physics of the Earth and Planetary Interiors, v. 2, no. 5, p. 332-341, https://doi.org/10.1016/0031-9201(69)90026-0.","productDescription":"10 p.","startPage":"332","endPage":"341","numberOfPages":"10","costCenters":[],"links":[{"id":219594,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"2","issue":"5","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a6dd3e4b0c8380cd75348","contributors":{"authors":[{"text":"Lee, W.H.K.","contributorId":35303,"corporation":false,"usgs":true,"family":"Lee","given":"W.H.K.","affiliations":[],"preferred":false,"id":358175,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70009778,"text":"70009778 - 1969 - Geochemistry and origin of formation waters in the western Canada sedimentary basin-I. Stable isotopes of hydrogen and oxygen","interactions":[],"lastModifiedDate":"2020-11-29T20:38:46.584417","indexId":"70009778","displayToPublicDate":"1969-01-01T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Geochemistry and origin of formation waters in the western Canada sedimentary basin-I. Stable isotopes of hydrogen and oxygen","docAbstract":"Stable isotopes of hydrogen and oxygen, together with chemical analyses, were determined for 20 surface waters, 8 shallow potable formation waters, and 79 formation waters from oil fields and gas fields. The observed isotope ratios can be explained by mixing of surface water and diagenetically modified sea water, accompanied by a process which enriches the heavy oxygen isotope. Mass balances for deuterium and total dissolved solids in the western Canada sedimentary basin demonstrate that the present distribution of deuterium in formation waters of the basin can be derived through mixing of the diagenetically modified sea water with not more than 2.9 times as much fresh water at the same latitude, and that the movement of fresh water through the basin has redistributed the dissolved solids of the modified sea water into the observed salinity variations. Statistical analysis of the isotope data indicates that although exchange of deuterium between water and hydrogen sulphide takes place within the basin, the effect is minimized because of an insignificant mass of hydrogen sulphide compared to the mass of formation water. Conversely, exchange of oxygen isotopes between water and carbonate minerals causes a major oxygen-18 enrichment of formation waters, depending on the relative masses of water and carbonate. Qualitative evidence confirms the isotopic fractionation of deuterium on passage of water through micropores in shales.
The Paradox Basin region is approximately bounded by the south flank of the Uinta Basin to the north, the Uncompahgre uplift and San Juan Mountains to the east, the Four Corners structural platform to the southeast, the north rim of the Black Mesa Basin and the Grand Canyon to the south and southwest, and the Wasatch Plateau and Hurricane fault system to the west. Some of these geologic features are areas of ground-water recharge or discharge whereas others such as the Four Corners platform do not directly influence fluid movement. The aquifer systems studied were: (1) Mississippian rocks; (2) Pinkerton Trail Limestone of Wengerd and Strickland, 1954; (3) Paradox Member of the Hermosa Formation; (4) Honaker Trail Formation of Wengerd and Matheny, 1958; (5) Permian rocks.
Recharge in the Paradox Basin occurs on the west flank of the San Juan Mountains and along the west side of the Uncompahgre uplift. The direction of ground-water movement in each analyzed unit is principally southwest-ward toward the topographically low outcrop areas along the Colorado River in Arizona. However, at any point in the basin, flow may be in some other direction owing to the influence of intrabasin recharge areas or local obstructions to flow, such as faults or dikes. A series of potentiometric surface maps was prepared for the five systems studied. Material used in construction of the maps included outcrop altitudes of springs and streams, drill-stem tests, water-well records, and an electric analog model of the entire basin. Many structurally and topographically high areas within the basin are above the regional potentiometric surface; recharge in these areas will drain rapidly off the high areas and adjust to the regional water level.
With a few exceptions, most wells in formations above the Pennsylvanian contain fresh (< 1,000 mg/l T.D.S.2) to moderately saline (< 10,000 mg/l T.D.S.) water. In only a few cases are true brines (> 35,000 mg/l T.D.S.) reported. Most water samples from strata below the Permian are brines of the sodium chloride type but with large amounts of calcium sulfate or calcium chloride type water commonly occurring. Because evaporite facies occur in the Paradox Member, this unit has brines with as much as 400,000 mg/l dissolved solids content.
Previous analysis of the San Juan Basin has indicated the presence of an osmotic membrane system. The highly permeable Jurassic formations were postulated to be the outflow side of the membrane. It is also possible that the Upper Paleozoic units with known brines and with an otherwise inexplicably high potentiometric surface in the Four Corners area of New Mexico could be the outflow receptors of the San Juan membrane system.
","language":"English","publisher":"Elsevier","doi":"10.1016/0009-2541(69)90050-3","issn":"00092541","usgsCitation":"Hanshaw, B., and Hill, G., 1969, Geochemistry and hydrodynamics of the Paradox Basin region, Utah, Colorado and New Mexico: Chemical Geology, v. 4, no. 1-2, p. 263-294, https://doi.org/10.1016/0009-2541(69)90050-3.","productDescription":"32 p.","startPage":"263","endPage":"294","numberOfPages":"32","costCenters":[],"links":[{"id":221376,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado, New Mexico, Utah","otherGeospatial":"Paradox Basin region","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -110.390625,\n 34.32529192442733\n ],\n [\n -105.40283203124999,\n 34.32529192442733\n ],\n [\n -105.40283203124999,\n 39.30029918615029\n ],\n [\n -110.390625,\n 39.30029918615029\n ],\n [\n -110.390625,\n 34.32529192442733\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"4","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a16d4e4b0c8380cd55295","contributors":{"authors":[{"text":"Hanshaw, B.B.","contributorId":25928,"corporation":false,"usgs":true,"family":"Hanshaw","given":"B.B.","email":"","affiliations":[],"preferred":false,"id":361446,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hill, G.A.","contributorId":83666,"corporation":false,"usgs":true,"family":"Hill","given":"G.A.","email":"","affiliations":[],"preferred":false,"id":361447,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70045464,"text":"70045464 - 1969 - Hydrology of the San Luis Valley, south-central Colorado","interactions":[],"lastModifiedDate":"2013-05-23T11:41:05","indexId":"70045464","displayToPublicDate":"1969-01-01T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":6,"text":"USGS Unnumbered Series"},"seriesTitle":{"id":375,"text":"Open-File Report","active":false,"publicationSubtype":{"id":6}},"title":"Hydrology of the San Luis Valley, south-central Colorado","docAbstract":"An investigation of the water resources of the Colorado part of the San Luis Valley was begun in 1966 by the U.S. Geological Survey, in cooperation with the Colorado Water Conservation Board. (See index map, fig. 1). The purpose of the investigation is to provide information for planning and implementing improved water-development and management practices. The major water problems in the San Luis Valley include (1) waterlogging, (2) waste of water by nonbeneficial evapotranspiration, (3) deterioration of ground-water chemical quality, and (4) failure of Colorado to deliver water to New Mexico and Texas in accordance with the Rio Grande Compact. This report describes the hydrologic environment, extent of water-resource development, and some of the problems related to that development. Information presented is based on data collected from 1966 to 1968 and on previous studies. Subsequent reports are planned as the investigation progresses. The San Luis Valley extends about 100 miles from Poncha Pass near the northeast corner of Saguache County, Colo., to a point about 16 miles south of the Colorado-New Mexico State line. The total area is 3,125 square miles, of which about 3,000 are in Colorado. The valley is nearly flat except for the San Luis Hills and a few other small areas. The Colorado part of the San Luis Valley, which is described in this report, has an average altitude of about 7,700 feet. Bounding the valley on the west are the San Juan Mountains and on the east the Sangre de Cristo Mountains. Most of the valley floor is bordered by alluvial fans deposited by streams originating in the mountains, the most extensive being the Rio Grande fan (see block diagram, fig. 2 in pocket). Most of the streamflow is derived from snowmelt from 4,700 square miles of watershed in the surrounding mountains. The northern half of the San Luis Valley is internally drained and is referred to as the closed basin. The lowest part of this area is known locally as the \"sump.\" The remainder of the valley is drained by the Rio Grande and its tributaries. The climate of the San Luis Valley is arid, and a successful agricultural economy would not be possible without irrigation. It is characterized by cold winters, moderate summers, and much sunshine. The average annual precipitation on the valley floor ranges from 7 to 10 inches. More than half the precipitation occurs from July to September. Moisture deficiency in the valley is shown by the graph comparing pan evaporation and precipitation {fig. 3}. For the years 1961-67 average pan evaporation for the period April through September was 52.25 inches, but average precipitation for the period was only 5.02 inches. Average annual precipitation was 7.8 inches. Owing to the short growing season (90-120 days), crops a.re restricted mainly to barley, oats, potatoes, and other vegetables.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Denver, CO","doi":"10.3133/70045464","collaboration":"Prepared in cooperation with the Colorado Water Conservation Board","usgsCitation":"Emery, P.A., Boettcher, A.J., Snipes, R., and Mcintyre, H., 1969, Hydrology of the San Luis Valley, south-central Colorado: Open-File Report, ii, 22 p.; 3 Plates: 23.79 x 27.78 inches or smaller, https://doi.org/10.3133/70045464.","productDescription":"ii, 22 p.; 3 Plates: 23.79 x 27.78 inches or smaller","numberOfPages":"26","additionalOnlineFiles":"Y","temporalStart":"1966-01-01","temporalEnd":"1968-12-31","costCenters":[{"id":191,"text":"Colorado Water Science Center","active":true,"usgs":true}],"links":[{"id":271022,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/unnumbered/70045464/report-thumb.jpg"},{"id":272738,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/unnumbered/70045464/report.pdf"},{"id":272739,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/unnumbered/70045464/plate-2.pdf"},{"id":272740,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/unnumbered/70045464/plate-4.pdf"},{"id":272741,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/unnumbered/70045464/plate-7.pdf"}],"country":"United States","state":"Colorado","county":"Alamosa;Conejos;Costilla;Custer;Huerfano;Rio Grande;Saguache","otherGeospatial":"San Luis Valley","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -105.25,37.0 ], [ -105.25,38.5 ], [ -106.75,38.5 ], [ -106.75,37.0 ], [ -105.25,37.0 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"516fc466e4b05024ef3cd408","contributors":{"authors":[{"text":"Emery, P. A.","contributorId":49392,"corporation":false,"usgs":true,"family":"Emery","given":"P.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":477543,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Boettcher, A. J.","contributorId":25965,"corporation":false,"usgs":true,"family":"Boettcher","given":"A.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":477541,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Snipes, R.J.","contributorId":16813,"corporation":false,"usgs":true,"family":"Snipes","given":"R.J.","affiliations":[],"preferred":false,"id":477540,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Mcintyre, H.J. Jr.","contributorId":34027,"corporation":false,"usgs":true,"family":"Mcintyre","given":"H.J.","suffix":"Jr.","email":"","affiliations":[],"preferred":false,"id":477542,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70011562,"text":"70011562 - 1969 - The determination of the acoustic parameters of volcanic rocks from compressional velocity measurements","interactions":[],"lastModifiedDate":"2020-11-29T18:04:51.48621","indexId":"70011562","displayToPublicDate":"1969-01-01T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2071,"text":"International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts","active":true,"publicationSubtype":{"id":10}},"title":"The determination of the acoustic parameters of volcanic rocks from compressional velocity measurements","docAbstract":"A statistical analysis was made of the relationship of various acoustic parameters of volcanic rocks to compressional wave velocities for data obtained in a volcanic region in Nevada. Some additional samples, chiefly granitic rocks, were also included in the study to extend the range of parameters and the variety of siliceous rock types sampled. Laboratory acoustic measurements obtained on 62 dry core samples were grouped with similar measurements obtained from geophysical logging devices at several depth intervals in a hole from which 15 of the core samples had been obtained. The effects of lithostatic and hydrostatic load on changing the rock acoustic parameters measured in the hole were noticeable when compared with the laboratory measurements on the same core. The results of the analyses determined by grouping all of the data, however, indicate that dynamic Young's, shear and bulk modulus, shear velocity, shear and compressional characteristic impedance, as well as amplitude and energy reflection coefficients may be reliably estimated on the basis of the compressional wave velocities of the rocks investigated. Less precise estimates can be made of density based on the rock compressional velocity.
The possible extension of these relationships to include many siliceous rocks is suggested.
","language":"English","publisher":"Elsevier","doi":"10.1016/0148-9062(69)90022-9","issn":"01489062","usgsCitation":"Carroll, R.D., 1969, The determination of the acoustic parameters of volcanic rocks from compressional velocity measurements: International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, v. 6, no. 6, p. 557-579, https://doi.org/10.1016/0148-9062(69)90022-9.","productDescription":"23 p.","startPage":"557","endPage":"579","numberOfPages":"23","costCenters":[],"links":[{"id":221182,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"6","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505baa9fe4b08c986b3228db","contributors":{"authors":[{"text":"Carroll, R. D.","contributorId":53373,"corporation":false,"usgs":true,"family":"Carroll","given":"R.","email":"","middleInitial":"D.","affiliations":[],"preferred":false,"id":361410,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70010497,"text":"70010497 - 1969 - Methane-derived marine carbonates of pleistocene age","interactions":[],"lastModifiedDate":"2020-11-29T19:34:34.151245","indexId":"70010497","displayToPublicDate":"1969-01-01T00:00:00","publicationYear":"1969","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3338,"text":"Science","active":true,"publicationSubtype":{"id":10}},"title":"Methane-derived marine carbonates of pleistocene age","docAbstract":"In some calcium carbonate-bearing sandstones from the edge of the continental shelf off the northeast United States, the δC13 range is from -30 and -60 per mil for both aragonite and high-magnesium calcite. The δC13 of co-existing shells of Modiolus sp. is normal (+ 1.7 to -2.7 per mil). The δO18 values of around + 3.5 per mil in all samples suggest deposition at temperatures around 0°C. Quaternary methane oxidized either chemically or microbiologically to carbon dioxide is the probable source of carbon in these carbonates.