Analysis of repeated leveling surveys suggests significant contemporary vertical deformation in at least three distinct areas in the vicinity of the Rio Grande rift. These areas include Socorro, New Mexico; the Diablo Plateau region of Trans-Pecos Texas; and the Espanola basin in northern New Mexico. The Socorro area is characterized by uplift relative to its surroundings. Maximum relative uplift of about 20 cm between 1911 and 1951 occurred about 25 km north of Socorro. The primary anomaly, defined by a north-south profile between El Paso, Texas and Albuquerque, New Mexico, extends from 15 km south to 55 km north of Socorro. The Diablo Plateau region is also characterized by relative uplift. Uplift of approximately 13 cm during the period from 1934 to 1958 was observed along an approximately east-west profile from El Paso, Texas to Carlsbad, New Mexico. The leveling anomaly suggests broad uparching of the basin and range structures between El Paso and Carlsbad, with the maximum occurring near the eastern side of the Diablo Plateau. In contrast to the observed relative uplift near Socorro and on the Diablo Plateau, leveling data within the Espanola basin in northern New Mexico show a pronounced zone of relative subsidence. Maximum observed subsidence relative to nearby benchmarks was 4.9 cm between September 1934 and March 1939. Subsidence is observed over a distance of approximately 19 km, extending from 4 km north to 23 km north-northwest of Espanola. The consistency of available geological and geophysical evidence suggests that these three leveling anomalies are due to crustal deformation and not to measurement errors or near surface effects. Although other possibilities exist, deformation in all three areas can be related, with different degrees of uncertainty, to crustal magmatic activity. This hypothesis is consistent with the tectonic history of the rift, being a predominently extensional environment where magma intrusion might be expected. Tertiary intrusives and crustal conductivity anomalies occur near all three locations. The observed patterns of deformation in all three areas are generally consistent with relatively simple models of magma intrusion in the crust. The Socorro and Espanola areas are seismically active, have high heat flow, are characterized by Quaternary volcanics and are transected by major structural lineaments. On the other hand, the Diablo Plateau region is aseismic at present and lacks evidence of young volcanic activity. The most direct evidence for magma within the crust comes from seismic wave propagation anomalies (reflected phases from magma-crust boundary and filtering effects of low rigidity material) which so far have been detected only in the Socorro area. Thus, although crustal magmatic activity appears to be the most likely cause for the crustal movements described here, the evidence supporting this hypothesis is strongest for the Socorro area.

Seismology and the IGY Jack Oliver, Jack Oliver Lamont Geological Observatory, Palisades, New YorkSearch for more papers by this author Jack Oliver, Jack Oliver Lamont Geological Observatory, Palisades, New YorkSearch for more papers by this author Book Editor(s):Hugh Odishaw, Hugh OdishawSearch for more papers by this authorStanley Ruttenberg, Stanley RuttenbergSearch for more papers by this author First published: 01 January 1958 https://doi.org/10.1029/GM002p0190Citations: 1Book Series:Geophysical Monograph Series AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Geophysics and the IGY: Proceedings of the Symposium at the Opening of the International Geophysical Year, Volume 2 RelatedInformation

As many of you are aware, the American Political Science Association has recently experienced an extraordinary outpouring of frustration with the current state of the American Political Science Review, the APSA, and the profession generally. An anonymous scholar writing as "Mr. Perestroika" circulated to an extensive roster of political scientists a passionate memo asking many provocative, indeed painful, questions. Why do so many leaders of our profession not even read, much less submit, to the APSR7 Why is purchase of the APSR made mandatory for membership, thus subsidizing a journal many find unsatisfactory, instead of permitting membership without the journal or with other journals? Why do the APSA Council and APSR Editorial Board seem to be chosen essentially by their predecessors? Why does the APSR and why do other prominent professional fora seem so intensively focused on technical methods, at the expense of the great, substantive political questions that actually intrigue many APSA members, as well as broader intellectual audiences? Though some recipients may have felt uncomfortable with the anonymous authorship and the highly polemical tone of this post, nonetheless an astonishing number of scholars, from all ranks of the profession, felt impelled to announce that they, too, shared these profound dissatisfactions with the status quo. Many noted that in 1998 an APSA membership survey reportedly found that, in fact, a very large proportion of APSA members, to say nothing of scholars who have given up on APSA, were critical of the current condition of the APSR. A lively discussion ensued, in which scholars discussed whether the problems arose from the biases of APSR editors and APSA leaders, from more structural problems in the reviewing processes, or from problems in AmeriEditor's Note

Share Icon Share Twitter Facebook Reddit LinkedIn Reprints and Permissions Cite Icon Cite Search Site Citation Jack Oliver, Henry Frankel; Shocks and Rocks: Seismology in the Plate Tectonics Revolution. Physics Today 1 May 1997; 50 (5): 63–64. https://doi.org/10.1063/1.881836 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentPhysics Today Search Advanced Search

This COCORP deep seismic survey provides a comprehensive image of the southeast-Texas part of the Gulf passive margin and its accreted Ouachita arc foundation. Beneath the updip limit of the Cenozoic sediment wedge, a prominent antiformal structure is imaged within the interior zone of the buried late Paleozoic Ouachita orogen. The structure appears to involve Precambrian Grenville basement. The crest of the antiform is coincident with the Cretaceous-Tertiary Luling-Mexia-Talco fault zone. Some of these faults dip to the northwest, counter to the general regional pattern of down-to-the-basin faulting, and appear to sole into the top of the antiform, suggesting that the Ouachita structure has been reactivated as a hingeline to the subsiding passive margin. The antiform may be tied via this fault system and the Ouachita gravity gradient to the similar Devils River, Waco, and Benton uplifts, interpreted as Precambrian basement-cored massifs.Above the Paleozoic sequence, a possible rift-related graben is imaged near the updip limit of Jurassic salt.Paleoshelf edges of the major Tertiary depositional sequences are marked by expanded sections disrupted by growth faults and shale diapirs. Within the Wilcox Formation, the transect crosses the mouth of the 900-m-deep Yoakum Canyon, a principal pathway of sediment delivery from the Laramide belt to the Gulf.Beneath the Wilcox, the Comanchean (Lower Cretaceous) shelf edge, capped by the Stuart City reef, is imaged as a pronounced topographic break onlapped by several moundy sediment packages. Because this segment of the line parallels strike, the topographic break may be interpreted as a 2000-m-deep embayment in the Cretaceous shelf-edge, and possibly a major submarine canyon older and deeper than the Yoakum Canyon.

This paper describes a synthesis characterized by broad scope, substantial support, and some speculation. The framework for the synthesis is the speculative concept that the process of convergence and collision of large landmasses disrupts the fluid regime of the collision zone and adjoining areas. The disturbed fluids leave a record of their disruption and transport in great spots and stains. Some of these spots and stains persist in the modern geologic record where they are known as mineral deposits, mineral occurrences, oil fields, gas fields, tar sands, diagenesis, authigenesis, metamorphism, dolomitization, fluid inclusions, and paleoremagnetization. Various observed characteristics of these phenomena provide supporting evidence of such diversity and consistency that the concept seems firmly rooted in observation. Nevertheless, many opportunities for further testing remain. If the synthesis is more or less correct, then a major link between plate tectonics, or global-scale geodynamics, and a wide variety of terrestrial geological observations of lesser scale is in hand.

In keeping with the nature of the symposium, part I is a brief summary of the author's recollection of research activities in earthquake seismology at the Lamont Geological Observatory that contributed to the development of the concept of plate tectonics in the 1960's.As the productive and euphoric period of the late 1960's that marked the advent of plate tectonics waned, it was followed in the 1970's and 1980's by various efforts to cause yet another major advance in earth science. One focus of such efforts was, and is, the continental crust. A new paradigm has not yet appeared, but part II describes how the earth scientist's perspective of the continents is changing as a consequence of those efforts. Surface geology can now sometimes be extrapolated to the base of the crust. Comprehensive global exploration of the entire volume of the continental crust has become a reasonable and achievable goal. The Moho, the traditional crust-mantle boundary, is recognized as a dynamic feature and no longer is considered the lower bound of the continent. Fluids propagating for long distances horizontally in the crust may link a variety of geologic phenomena with the large-scale geodynamic processes of the interior. The story of the earth's slowly evolving continents is rapidly evolving.

A pair of oppositely dipping, crustal-scale shear zones imaged within Grenville basement beneath the Paleozoic cover of Ohio can be correlated, via geopotential lineaments, with similarly oriented geologic and seismically imaged structures hundreds of kilometres to the northeast and southwest, suggesting a relatively simple structural framework for the eastern midcontinent region. An east-dipping zone extending from Lake Huron through western Ohio, and possibly farther southwest, marks the western edge of the Grenville province. Perhaps of greater consequence to an understanding of Grenville tectonics is the discovery of a west-dipping zone underlying the Appalachian basin from northern Alabama to New York within the Grenville province. Correlation of this feature with the seismogenic Clarendon-Linden fault in western New York and a boundary between terranes containing magmatic-arc rocks exposed in Canada suggests that it could mark the site of an intra-Grenville province suture zone. Implications of this interpretation are that the Precambrian foundation of the eastern U.S. midcontinent comprises a relatively simple assemblage of laterally extensive terranes or belts of coeval terranes accreted by familiar plate tectonic processes, and that deep seismic profiling is an effective tool for mapping the three-dimensional distribution of these terranes.

Research Article| February 01, 1988 Discovery and innovation in geoscience: Address as Retiring President of The Geological Society of America, October 1987 JACK OLIVER JACK OLIVER 1Institute for the Study of the Continents and Department of Geological Sciences, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar Author and Article Information JACK OLIVER 1Institute for the Study of the Continents and Department of Geological Sciences, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1988) 100 (2): 157–159. https://doi.org/10.1130/0016-7606(1988)100<0157:DAIIG>2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation JACK OLIVER; Discovery and innovation in geoscience: Address as Retiring President of The Geological Society of America, October 1987. GSA Bulletin 1988;; 100 (2): 157–159. doi: https://doi.org/10.1130/0016-7606(1988)100<0157:DAIIG>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract No abstract available This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Research Article| December 01, 1988 COCORP profiles from the Montana plains: The Archean cratonic crust and a lower crustal anomaly beneath the Williston basin Thomas S. Latham; Thomas S. Latham 1Institute for the Study of the Continents, Snee Hail, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar J. Best; J. Best 2Department of Geological Sciences and Institute for the Study of the Continents, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar T. Chaimov; T. Chaimov 2Department of Geological Sciences and Institute for the Study of the Continents, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar J. Oliver; J. Oliver 2Department of Geological Sciences and Institute for the Study of the Continents, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar L. Brown; L. Brown 2Department of Geological Sciences and Institute for the Study of the Continents, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar S. Kaufman S. Kaufman 2Department of Geological Sciences and Institute for the Study of the Continents, Snee Hall, Cornell University, Ithaca, New York 14853-1504 Search for other works by this author on: GSW Google Scholar Geology (1988) 16 (12): 1073–1076. https://doi.org/10.1130/0091-7613(1988)016<1073:CPFTMP>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Thomas S. Latham, J. Best, T. Chaimov, J. Oliver, L. Brown, S. Kaufman; COCORP profiles from the Montana plains: The Archean cratonic crust and a lower crustal anomaly beneath the Williston basin. Geology 1988;; 16 (12): 1073–1076. doi: https://doi.org/10.1130/0091-7613(1988)016<1073:CPFTMP>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract New COCORP deep seismic reflection profiles from the Montana plains between the Rocky Mountains and the Williston basin image the crystalline continental basement of the Archean Wyoming cratonic province on a regional scale. The crust is, in general, reflective throughout its entire thickness. West of the Williston basin, the crust-mantle boundary is at the base of the reflective zone and is not marked by the presence of any distinctive reflections. The lowermost crust beneath the Williston basin is, in contrast, characterized by a prominent, laterally extensive zone of relatively high-amplitude reflections. If, as the spatial correlation suggests, the anomalously reflective lower crustal zone is causally related to the subsidence of the basin, then the data place constraints in addition to those of the sedimentary record on physical models for the evolution of the Williston basin. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Research Article| September 01, 1988 Structure of the central Death Valley pull-apart basin and vicinity from COCORP profiles in the southern Great Basin LAURA SERPA; LAURA SERPA 1Institute for the Study of Continents and Department of Geological Sciences, Cornell University, Ithaca, New York 14853 Search for other works by this author on: GSW Google Scholar BEATRICE DE VOOGD; BEATRICE DE VOOGD 1Institute for the Study of Continents and Department of Geological Sciences, Cornell University, Ithaca, New York 14853 Search for other works by this author on: GSW Google Scholar LAUREN WRIGHT; LAUREN WRIGHT 2Department of Geosciences Pennsylvania State University, University Park, Pennsylvania 16802 Search for other works by this author on: GSW Google Scholar JAMES WILLEMIN; JAMES WILLEMIN 3Institute for the Study of Continents, Cornell University, Ithaca, New York 14853 Search for other works by this author on: GSW Google Scholar JACK OLIVER; JACK OLIVER 1Institute for the Study of Continents and Department of Geological Sciences, Cornell University, Ithaca, New York 14853 Search for other works by this author on: GSW Google Scholar ERNEST HAUSER; ERNEST HAUSER 3Institute for the Study of Continents, Cornell University, Ithaca, New York 14853 Search for other works by this author on: GSW Google Scholar BENNIE TROXEL BENNIE TROXEL 4Department of Geology, University of California, Davis, California 95616 Search for other works by this author on: GSW Google Scholar Author and Article Information LAURA SERPA 1Institute for the Study of Continents and Department of Geological Sciences, Cornell University, Ithaca, New York 14853 BEATRICE DE VOOGD 1Institute for the Study of Continents and Department of Geological Sciences, Cornell University, Ithaca, New York 14853 LAUREN WRIGHT 2Department of Geosciences Pennsylvania State University, University Park, Pennsylvania 16802 JAMES WILLEMIN 3Institute for the Study of Continents, Cornell University, Ithaca, New York 14853 JACK OLIVER 1Institute for the Study of Continents and Department of Geological Sciences, Cornell University, Ithaca, New York 14853 ERNEST HAUSER 3Institute for the Study of Continents, Cornell University, Ithaca, New York 14853 BENNIE TROXEL 4Department of Geology, University of California, Davis, California 95616 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1988) 100 (9): 1437–1450. https://doi.org/10.1130/0016-7606(1988)100<1437:SOTCDV>2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation LAURA SERPA, BEATRICE DE VOOGD, LAUREN WRIGHT, JAMES WILLEMIN, JACK OLIVER, ERNEST HAUSER, BENNIE TROXEL; Structure of the central Death Valley pull-apart basin and vicinity from COCORP profiles in the southern Great Basin. GSA Bulletin 1988;; 100 (9): 1437–1450. doi: https://doi.org/10.1130/0016-7606(1988)100<1437:SOTCDV>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract COCORP deep seismic reflection profiles in the vicinity of the central Death Valley pull-apart basin in southeastern California provide three-dimensional information on the subsurface of an active extensional terrane. Variations in the orientation and density of reflectors indicate that the crust and upper mantle of the region is divisible into three seismic zones which may represent regions of differing lithology, rheology, or both. The reflections in the upper ∼5 s (15 km) of the data have gentle to moderate dips; between 5 and 10 s, reflections are predominantly subhorizontal; and below ∼ 10 s (30 km), there are no notable reflections. The boundaries between the above reflecting zones are marked by prominent reflecting horizons which are continuous throughout the survey region.The observed reflection geometries resemble those predicted by the crustal model of the region proposed by Wright and Troxel (1973) on the basis of geological studies. In addition, many of the upper-crustal reflectors can be traced directly to mapped features. Based on those correlations, the upper reflecting zone (0-5 s) is interpreted to be a region of brittle deformation with the various upper-crustal reflectors interpreted as faults and basin sediments. The reflecting horizon at the base of the upper zone appears to be the lower boundary of the faulted upper crustal blocks and, it has been suggested that it locally includes partially molten rock. The observed geometries and amplitudes of reflections from the lower crust (15-30 km depth or 5-10 s two-way traveltime) are consistent with the model of Wright and Troxel for a ductilely deformed and intruded lower crust. The prominent reflecting horizon at the base of that zone is designated the reflection Moho and the seismically transparent lowest zone appears to correspond to the upper mantle.The seismic data define a zone of faults (referred to here as the "Wingate Wash fault zone") which appears to form the southern boundary of the central Death Valley basin and also may have provided a conduit for the migration of magma from a mid-crustal magma body to the surface. The Wingate Wash fault zone appears to intersect the southern Death Valley fault zone and the frontal faults of the Black Mountains in the subsurface beneath the youngest volcanic edifice in the region. Those three fault zones appear to separate the Panamint, Owlshead, and Black Mountain upper-crustal fault blocks. From the available data, a reconstruction of the possible fault-block movements during the time of basin subsidence is presented. That reconstruction suggests that the central Death Valley basin formed as a result of the combined down-to-the-east rotation and northwest translation of the fault blocks in manner similar to that proposed by Reches for other parts of the Basin and Range. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.