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https://ntrs.nasa.gov/search.jsp?R=19760011108 2020-03-22T16:23:33+00:00Z 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) ^ t ^ SITE EVALUATION FOR LASER N SATELLITE-TRACKING STATIONS N. H. MAO and R. A. MOHR (NASA-CR-146427) SITE EVALUATION FOR LASER N76-18196 SATELLITE - TRACKING STATIONS ( Smithsonian Astrophysical Observatory) 131 p HC $6.00 CSCL 14B Unclas G3/14 20043 v .............. ...:..:..:..:.... MAR 1978 rt' c7j` RECEIVED r - NASA STI FACILITY j INPUT BRANCH \ ,r r. Smithsonian Astrophysical Observatory SPECIAL REPORT 371 I Research in Space Science SAO Special Report No. 371 SITE EVALUATION FOR LASER SATELLITE-TRACKING STATIONS N. K. Mao and P. A. Mohr February 6, 1976 Smithsonian Institution Astrophysical Observatory Cambridge, Massachusetts 02138 TABLE OF CONTENTS Page It ABSTRACT ........................................................ vii I 1 INTRODUCTION .................................................... 1 2 COMODORO RIVADAVIA, ARGENTINA ......... ...... ................ 9 3 BERMUDA, ATLANTIC OCEAN ........ .. ... ................ .. 13 4 ORRORAL VALLEY, AUSTRALIA . ..................... .......... 17 5 NATAL AND PORTO ALEGRE, BRAZIL ...................................... 21 6 SAO FRANCISCO, BRAZIL ....... ............ ............... .. 23 7 FORT RESOLUTION, CANADA 25 8 QUITO, ECUADOR ...... ......... ... ........................ 29 9 CAIRO, EGYPT .................................................... 33 10 DEBRE ZEIT, ETHIOPIA ............. ..... .. ........... .. 37 11 ATHENS, GREECE .............. ......... ............. ..... .. 41 12 BANGALORE, INDIA ............................. ... .......... 45 j 13 NAINI TAL, INDIA .......... ....... .. ........ ........ 49 i 14 TOKYO, JAPAN .. .. ...... ............ ........... ....... 51 r 15 PUSAN, KOREA ............. ......................... ..... 57 16 RAPA NUI, PACIFIC OCEAN .. .. ...... 59 17 GUAM, PACIFIC OCEAN ............ .... ...... ............. 65 18 MAUI, HAWAII, PACIFIC OCEAN ..................................... 69 19 TUTUILA, SAMOA, PACIFIC OCEAN ................................... 75 20 TAHITI, PACIFIC OCEAN ................................................. 79 21 WAKE ISLAND, PACIFIC OCEAN ............ .. ..................... 83 iii 1 TABLE OF CONTENTS (Cont.) Page 22 AREQUIPA, PERU .................................................. 85 23 SAN FERNANDO, SPAIN ..................... ........... ......... 89 24 UPPSALA, SWEDEN ....... ... ...... ....... ................ 93 25 BANGKOK, THAILAND . .......................... ........... 97 26 MT. HOPKINS, ARIZONA, USA ................. .......... .. 101 27 CONCLUSIONS ..................................................... 107 28 ACKNOWLEDGMENTS ... .... ...... ........... ..... 109 29 REFERENCES ........... ......... .... .......... .... ... .. 111 APPENDIX A: GEOLOGICAL TIME SCALE ...... ...... .............. A-1 t ILLUSTRATIONS Page 1 World map showing station sites, earthquake epicenters for the period 1961 through 1967, relative motions of plates, andshield areas .............................................. 2 Tectonic map of southern Argentina ............................ 11 3 Age of ocean basins of the North Atlantic, with inset of Bermuda...................................................... 14 4 The Australian Shield, showing its provinces, some geophysical parameters, and its present seismicity ....................... 18 5 Tectonic outline of the Brazilian platform ................... 22 6 Geological map of the northwestern corner of the Canadian Shield.. .................... ..................... .. .. 26 7 Seismicity of Peru and Ecuador for the years 1961-1968 ....... 30 8 Geological map of Ecuador .................................... 32 9 Tectonic map of E gypt ......... .... ..... ..... 34 10 Structural map of the northern sector of the main Ethiopian rift . ......... ........ ... .. .... ..... .. .... 38 11 Structural map and present seismicity of Ethiopia ............ 40 12 Tectonic map of the Hellenides, with Moho depth computed from gravity and seismic data ..................................... 42 13 Tectonic map of India and adjoining regions .................. 46 14 Map of India showing seismic zones ....... ..... ...... 47 - 15 Structural elements of the Philippine Sea with tectonic prov- incesof Korea .. .. ...... .. .... 52 16 Tectonic map of the south Fossa Magna area and uplift of marine Simosueyosi terrace of the Kanto Plain during the last 125,000 yr ... .. ... ... .... ....... ...... 54 17 Map showing epicenters of earthquakes for '1961-1972,,physio- graphic features of the east Pacific Ocean, and earthquake focal-mechanism solutions . .. ... ..... .... .... 60 C ', v ILLUSTRATIONS (Cont.) Page 18 Geological map of Rapa Nui ......... ............. .......... 61 19 Structural map of Guam and vicinity .......................... 66 20 Loci of shield volcanoes in the Hawaiian-Emperor chain ....... 70 21 Geological map of the island of Maui ......................... 71 22 Sketch map of Samoa islands region ..... .. ................ 76 23 Geological map of Tutuila Island .. ............... ........ 77 24 Sketch map of Tahiti ......................................... 80 25 Sketch map of the Pacific Ocean showing tectonic features and the age boundary of the ocean basin .......................... 81 26 Geological map of Peru ... ..... ....... ..........• ..... 86 27 Map showing seismic activity in the Azores-Gibraltar region between 1910 and 1970, and the tectonic divisions of the westernmost part of the Alpine chain ......... ............ 90 28 Tectonic map of the Baltic Shield, with contemporary uplift .. 94 29 Geological map of Thailand ..................... ... •.... 98 30 Tectonic map of the Mt. Hopkins area ......................... 102 31 Map showing heat flow and physiographic provinces in the western United States ...... ....... .. .... .. 104 TABLES 1 Strain-rate and strain-release risks of the stations investi- gated for potential laser sites .............................. 5 2 Monthly and annual mean-cloudiness data ...................... 6 3 Operational factors ......... ... ........... ... 7 4 Summary of factors for evaluation of laser stations ..........,108 i i vi }} t i 1 ^ 1 ABSTRACT Twenty-six locations for potential laser satellite-tracking stations, four of them actually already occupied in this role, have been reviewed in terms of their known local and regional geology and geophysics. Laser track- ing techniques are now reaching a precision where tectonic motions of station sites can be significant. d The chosen sites are scattered over the globe such that every major plate, except only for Antarctica, carries at least one site. In selecting the locations, preference has been given to shield areas stable since the early history (> 2 G.y.) of the earth. Other favorable criteria include re- moteness from active plate margins or intrapl ate deformation zones and from recently glaciated areas and coastal margins. The station sites have been classified in a simple scheme incorporating strain-accumulation and strain release (earthquake) risks. Fifteen of the 26 sites qualify as suitable for a stable station whose a motions are likely to reflect only gross plate motion. The others, including two of the present laser station sites (Arequipa and Athens), fail to qualify unless ext; °d monitoring schemes can be included, such as precise geodetic surveying of ground deformation. 3 Additional to their geological and geophysical constraints, the sites are considered briefly in terms of weather and operational factors, 1 vii SITE EVALUATION FOR LASER SATELLITE-TRACKING STATIONS 9 N. H. Mao and P. A. Mohr 1. INTRODUCTION This report gives a preliminary evaluation of 26 existing or proposed laser-station sites from the point of view of their susceptibility to sig- nificant, local tectonic displacements. Operational and cloud-cover data are also included. The distribution of these sites is global (Figure 1) and, at least in the case of the existing stations, has been determined by factors that have not included consideration of tectonic stability. However, for the forthcoming generation of laser tracking stations, from which ranging preci- sions of only a few centimeters are expected, significant ground displace- ments within a regional reference frame of a few hundred kilometers can be effected, especially by seismic phenomena. In order for a station site to be considered reasonably free from tec- tonic risk sufficient to impinge on the expected precision of laser observa- tions made over a period of some years, it is desirable that the site be A. On a shield area, free from regional crustal deformation, gentle epeirogenic movements excepted, since about 2500 to 2000 m.y.