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General Disclaimer One Or More of the Following Statements May Affect This Document General Disclaimer One or more of the Following Statements may affect this Document This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible. This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available. This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white. This document is paginated as submitted by the original source. Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission. Produced by the NASA Center for Aerospace Information (CASI) (NASA—CR - 16908 WORKSHOI CN THE RIO GRANDE N82-26893 CRUSTAL MODELING AND Aki-LICATICNS OF I(EMOT13 SENSING fLuflar and klacetary lust.) 58 p 1IC AU4/MF A01 CSCL 08G Uncias G3/46 24228 WORKSHOP ON THE RIO GRANDE RIFT: CRUSTAL MODELING AND APPLICATIONS OF REMOTE SENSING Saiwe do (iriato We C*Wa romnaml (7) EAGI A- 12,000' 91000, 01000, 3000' Sea level ,6,000 'R^GEIVED 000-1 LPI Technical Report Number 81-07 two LUNAR AND PLANETARY INSTITUTE 3303 NASA ROAD I HOUSTON, TEXAS 77058 WORKSHOP ON THE RIO GRANDE RIFT; CRUSTAL MODELING AND APPLICATIONS OF REMOTE SENSING Editor: Douglas P. Blanchard A Workshop Cosponsored shy The Lunar and Planetary Institute and The Planetary and Earth Sciences Division of the Johnson Space Center April 21.23, 1980 Lunar and Planetary Institute 3303 NASA Road 1 Houston, Texas 77058 LPI Technical Report 81.07 r: ^4 Compiled in 1982 by the 1-11NAR AND I I I>ANU, I'AR1' INS Il Ill 11? 'the Institute is operated b y universities Space Research Association under Contract NASW»1180 with the National Aeronautics nod Spnee Administra►tints, Material in this doclunem may he copied Mhout restraint for library, ahmmet service, educational or personal march purposm; however, rcImMation of any portion recpdms the written permission of the authors as well as appropriate acknowledgment of this publication, this report play he cited its: Illanchard 1). 11. (1982) Warkshola rut lice Rio Grande Rtjt; C'rustnl Motleling rtrtrl ,^tpl►litvttiaars ol` Reillote 8en ing. 1,111 lich. Rpt. 81 .117, Lunar and Phine- tary Institute, Houston. S4 pp. papers in this report may be cited as: Author A, (19sm Title of put, Ire Workshop atr file Rio Grtutrle R(flr 011. of Altarl liar,^f rtttrl.^lhl^ltt^rttir^rrsr^/ l^'rat►trtlt^.^'r^t ►+iu,^^(l).1 1.Illauchard, i?tl,), p sx-yy. ITT lick Rpt. 81.07, Lunar and Plunctary Institute, Ilouston, 'Phis report. is distributed by: 1 111RARYANFORMAtIf)N (°1-.N111t Lunar 11110 Pho►ctary Institute 1101 NASA Road 1 ilomston, .1:S 77058 (+Lail order rctluestors will be invoiced for the cost of pmmnpc and 1landliog. ^r r ^^ Cover: Figure 2 fro. ^ Lipman, F. W. and Mehnert H. H. The Taos Volcanic Field, Northern Rio Grande Rift, New Mexico. In Rio Grande Rift. Tectonics and Magmatism (R, E, Riecker, Ed,) p. 289,311, Washington, American Geophysical Union, }i Contents Introduction 1 '` A f nctional definition of the Rio Grande Rift 3 Workshop Summary 5 Douglas Blanchard A Nonprioritized List of Major Scieotific and Resources Problems 9 Related to Continental Rifts in General and the Rio Grande Rift Specifically Summaries of Working Sessions 11 Nonprioritized List of Things Necessary to Advance the Present 19 State of Understanding of the Pico Grande Rift Program 21 Participants 25 Abstracts 29 The Role of Regional Linea►ncnts and Pre-existing Structures on the Late Cenozoic 31 Rio Grande Rift W. Scott Baldridge and .Andrea Kron Petrology and Resource Potential, Cenozoic Igneous Rocks, Trans Pecos, Texas 33 D. S. Barker Qua►ttitiatiue Analysis and Digital Processing of Potential Field Data frorn the 3a Rio Grande Rift, Colorado and New Mexico Robert C. Belcher Tectonic Interpretation from Seasat Radar Imagery; Southern Appalachians 37 J. P, Ford New Grauity and Magnetotelluric Studies in the Rio Grande Rift 39 G, R, Jiracek and F. S, Birch Some Results of COCORP Surveys in the Rio Grande Rift Area 42 S. Kaufman, et al. Regional Crustal Structure of the Rio Grande Rift 43 G. R. Keller An Approach to Curie Isotherm Mapping Using Long Wavelength Satellite Magnetic 44 Anomalies with Application to the Rio Grande Rift M. A. Mayhew Digital Lineament Analysis In Crustal Modeling 45 Kenneth T. Meehan Rio Grande Rift Overview 45 William R, Muehlberger Rifts: A Brief Review 47 William R. Muehlberger Crustal Structure of the Rio Grande Rift from Seismic Refraction Profiling: Some Results 46 and Future Prospects K. H. Olsen Passive Microwave Applications 50 J. F, Paris Magma Types and Chronology in the Raton-Clayton Volcanic Field; Analogies with the 51 Taos Plateau John C, Stormer, David W. Phelps, Joseph L, Wooden and Douglas P. Blanchard Introduction t This volume contains abstracts of talks presented at a Workshop on the Rio Grande Rift held at the Lunar and Planetary Institute on April 21- 23, 1980, Related materials, also found in this volume, include a summary of the workshop, results of the working sessions, the program, and participant list, This workshop was organized by Douglas Blanchard of the Planetary and Earth Sciences Division of the Johnson Space Center as part of their Program on Continental Rifts, run under the auspices of the NASA Office of Space and Tcrrestriai Applications Branch of Non-Renewable Resources, William Muehlberger of the University of Texas, Austin served as chairman of the sessions, Participants were asked to consider two questions; (1) What are the important problems associated with regions of continental rifting, and how are they important to the goals of the OSTA Non-Renewable Resources Program? (2) Which of these important problems are associated with the Rio Grande Rift, and how can they best be approached? The goals of the workshop were. (1) To outline the elements of a program that could address significant earth science problems by combining remote sensing and traditional geological, geophysical, and geochemical approaches; (2) To r'; identify specific areas and tasks related to the Rio Grande Rift which fit into such a program; and (3) To promote dialogue between ground-based and remote- sensing-based geoscientists, i? pRECEDING PAGE BLANK NOT FILMED 3 A functional definition of the Rio Grande Rift The more or less narrow linear belt extending from Leadville, Colorado, at least to El Paso, Texas, In which geologic and geophysical evidence suggests that the crust of the earth has been pulled apart and extended beginning about 26 My ago, The rift region includes all those parts of the crust and mantle affected by this extension and related processes during that interval of time, ^i 1( it kw" PRECEDING PACE ©LANK NOT FILMED 5 Workshop Summary Douglas Blanchard The "Workshop on the Rio Grande Rifts Crustal Modeling and Applications of Remote Sensing" was convened as part of Johnson Space Center's effort to define a project which advances the goals of the Non-Renewable Resources Branch of NASA's Office of Space and Terrestrial Applications, Approximately 45 scientists from a variety of geologic, geophysical, geochemical, and remote sensing areas of expertise attended the three day workshop. Nearly all the participants have been actively involved in research In the Rio Grande Rift. A list of participants is i, icluded in this report. The workshop was divided into 2 parts: (1) presentation and discussion sessions intended to familiarize attendees with the present state of knowledge about the Rio Grande Rift (RGR) and (2) working sessions intended to define topical problems, assess the potential contributions of various disciplines, especially remote sensing, and identify the best next steps for continued research, Monday was spent in a plenary session of information and discussion. Tuesday morning, the workshop split into two working groups, each with the same task: to make a nonprioritized list of significant geoscience and resource problems that can be addressed by the study of continental rifta, specifically the RGR. The unabridged lists are included in this report. The lists are somewhat uneven in level of detail and scale of problems, but they are inclusive, Tuesday afternoon was devoted to discipline oriented presentations on remote sensing techniques, The Tuesday evening session was an informal gathering with, for the most part, unstructured discussion among the various scientists and groups. Wednesday morning the group met in plenary session to categorize the questions formulated on Tuesday into topical research areas. After some discussion, the group agreed upon four topical areas: History of crustal deformation Configuration of the crust and mantle Composition and physical state of the crust-mantle system History of mapmatism Having agreed on the broad topical areas of research, the group then listed the various disciplines which could be brought to bear on these problems. They then engaged in a somewhat artificial exercise to rank the potential for contribution of each disci,)line. to each of the topical areas of research, The numerical ratings are presented in Table 1, The rankings are interesting, but the real value in the exercise was the discussion of the possibilities for interdisciplinary research that evolved, Recorders for each discipline were appointed to summarize the discussion; their comments are also included in this report, Finally, the group compiled a list of things that they felt were needed to advance the state of knowledge regarding the RGR and would foster fruitful interdisciplinary interaction, This list is also included. Discussion The workshop accomplished the entire process of information exchange and work laid out for it, This is a compliment to the participants who steadfastly stayed with the process and contributed to it throughout.
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