Crustal structure of the Colima rift, western Mexico: gravity models revisited
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Resumen
Se reportan resultados del análisis de la estructura del rift de Colima a partir del modelado de dos perfiles de gravedad orientados ESE-WNW con longitudes de 250 km y 280 km, localizados en el sector sur (SCR) y central (CCR) del graben. Estimaciones estadísticas de la profundidad de las interfaces se obtienen del análisis espectral. Las anomalías se modelan a partir de dos tipos distintos de modelos: un grupo asume que la anomalía es debida a fuentes profundas en la interface corteza-manto y el otro grupo considera una combinación de fuentes profundas y someras en un arreglo estratificado en la corteza. Para estimar el espesor cortical, se usan dos métodos iterativos que incluyen arreglos de prismas verticales o de polígonos para representar la interface y un contraste fijo de densidades. Las estimaciones estadísticas espectrales de profundidades y la topografía del Moho se usan para la construcción de modelos poligonales de corteza tipo Talwani. Los resultados del modelado indican una estructura para el sector sur del rift en la región costera que consiste en un graben 80-90 km de ancho y unos 7-9 km de profundidad. Este graben forma una continuación de la depresión que se extiende al NW del puerto de Manzanillo al SE del poblado de Tecomán. El Moho es más somero en la zona, donde tiene una profundidad de 17-18 km. Estos modelos difieren de interpretaciones previas en las cuales se propuso un modelo para el SCR con dos grábenes separados por un ‘ridge’. El graben al NE tiene un ancho de 35 km y una profundidad de 8 km y el otro graben al SE es 60 km de ancho y 6 km de profundidad. La estructura somera en el sector central CCR se caracteriza por una depresión asimétrica de 9-10 km de profundidad con el límite NW abrupto e intrusiones graníticas en esta zona. El espesor cortical disminuye en el sector occidental del graben de Colima hasta unos 22 km y es alrededor de 28-30 km en el perfil CCR.
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ALLAN, J. F., 1985. Sediment depth in the northern Colima graben from 3-D interpretation of gravity. Geofísica Internacional, 56, 992-1002. DOI: https://doi.org/10.22201/igeof.00167169p.1985.24.1.1063
ALLAN, J. F., 1986. Geology of the northern Colima and Zacoalco grabens, southwest Mexico: Late Cenozoic rifting in the Mexican volcanic belt. Geol. Soc. Am. Bull.,97, 473-485. DOI: https://doi.org/10.1130/0016-7606(1986)97<473:GOTNCA>2.0.CO;2
ALLAN, J. F., S. A. NELSON, J. F. LUHR, I. S. E. CARMICHAEL, M. WOPAT and P. J. WALLACE, 1991. Pliocene-Recent rifting in SW Mexico and associated volcanism: an exotic terrane in the making. In: The Gulf and Peninsular Province of the Californias, J. P. Dauphinand B. Simoneit (Eds.), Am. Assoc. Petrol. Geol. Mem, 47.
ALVA-VALDIVIA, L., J. URRUTIA-FUCUGAUCHI, H. BÖHNEL and D. J. MORAN-ZENTENO, 1991. Aeromagnetic anomalies and paleomagnetism in Jalisco and Michoacan, southern Mexico continental margin. Tectonophysics, 192, 169-190. DOI: https://doi.org/10.1016/0040-1951(91)90255-Q
BANDY, W. L., C. A. MORTERA-GUTIERREZ and J. URRUTIA-FUCUGAUCHI, 1993. Gravity field of the southern Colima graben, Mexico. Geofísica Internacional, 32, 561-567. DOI: https://doi.org/10.22201/igeof.00167169p.1993.32.4.602
BANDY, W. L., C. A. MORTERA-GUTIERREZ, J. URRUTIA-FUCUGAUCHI and T. W. C. HILDE, 1995. The subducted Rivera-Cocos plate boundary: Where is it, what is it, and what is its relationship to the Colima rift? Geophys. Res. Lett., 22, 3075-3078. DOI: https://doi.org/10.1029/95GL03055
BANDY, W., C. A. MORTERA-GUTIERREZ and J. URRUTIA-FUCUGAUCHI, 1996. Reply to comments on gravity field of the southern Colima graben. Geofísica Internacional, 35, 89-91. DOI: https://doi.org/10.22201/igeof.00167169p.1996.35.1.1106
BOURGOIS, J. et al., 1988. Active fragmentation of the North American plate: Offshore boundary of the Jalisco block off Manzanillo. C. R. Acad. Sci. Paris, t. 307, Ser. II, 1121-1130.
DE METS, C. and S. STEIN, 1990. Present-day kinematics of the Rivera plate and implications for tectonics in southwestern Mexico. J. Geophys. Res., 95, 21, 931-21, 948. DOI: https://doi.org/10.1029/JB095iB13p21931
ESCANERO-FIGUEROA, E.,1986. Profundidad media estimada depafiles espectrales gravimétricos. Tesis Ing. Geofísico, Facultad de Ingeniería, UNAM, 11988.
FERRARI, L., 1995. Miocene shearing along the northern boundary of the Jalisco block and the opening of the southern Gulf of California. Geology, 23, 751-754. DOI: https://doi.org/10.1130/0091-7613(1995)023<0751:MSATNB>2.3.CO;2
GARCIA-ABDESLEM, J., 1996. Comments on gravity field of the southern Colima graben. Geofísica Internacional, 35, 87-88. DOI: https://doi.org/10.22201/igeof.00167169p.1996.35.1.1105
GARDUÑO, V. H. and A. TIBALDI, 1991. Kinematic evolution of the continental active triple junction of the western Mexican volcanic belt. C. R. Acad. Sci. Paris, t 312, Ser. II, 135-142.
JOHNSON, C. A. and C. G. A. HARRISON, 1990. Neotectonics in central Mexico. Phys. Earth Planet. Inter., 64, 187-210. DOI: https://doi.org/10.1016/0031-9201(90)90037-X
LONDSDALE, P., 1995. Segmentation and disruption of the East Pacific rise in the mouth of the Gulf of California. Marine Geophys. Res., 17, 323-359. DOI: https://doi.org/10.1007/BF01227039
LUHR, J., S. NELSON, J. ALLAN and I. S. E. CARMICHAEL, 1985. Active rifting in southwestern Mexico: Manifestations of an incipient eastward spreading-ridge jump. Geology, 13, 54-57. DOI: https://doi.org/10.1130/0091-7613(1985)13<54:ARISMM>2.0.CO;2
MARSH, B. D. and J. G. MARSH, 1976. On global gravity anomalies and two-scale mantle convection. J. Geophys.Res., 81, 5267-5280. DOI: https://doi.org/10.1029/JB081i029p05267
MEDINA, F., J. M. ESPINDOLA, M. DE LA FUENTE and M. MENA, 1996. A gravity model of the Colima, Mexico region. Geofísica Internacional, 35, 409-414. DOI: https://doi.org/10.22201/igeof.00167169p.1996.35.4.533
MERCIER DE LEPINAY, B., F. MICHAUD, T. CALMUS, J. BOURGOIS, G. POUPEAU, P. SAINT-MARC and THE NAUTIMATE TEAM, 1997. Large Neogene subsidence event along the Middle America trench off Mexico (18-19 N): Evidence from submersible observations. Geology, 25, 387-390. DOI: https://doi.org/10.1130/0091-7613(1997)025<0387:LNSEAT>2.3.CO;2
MICHAUD, F., J. BOURGOIS and J. AUBOUIN, 1990. Active fragmentation of the North American plate: The Jalisco block, west Mexican Pacific coast. Oceanol. Acta, 10, 87-96.
MICHAUD, F., J. BOURGOIS, J.-F. PARROT, H. TAUD and M. KASSER, 1994. Tectonic development of the Jalisco triple junction (western Mexico) from SPOT-DEM data processing. C. R. Acad. Sci. Paris, t. 318, Ser. II, 1117-1124.
PAL, P. C., K. K. KHURANA and P. UNNIKRISHNAN, 1979. Two examples of spectral approach to source depth estimation in gravity and magnetics. Paleogeoph., 117 (78/79).
RADHAKRISHNA MURTHY, I. V. and B. RAO, 1979. Gravity anomalies of two-dimensional bodies of irregular cross-section with density contrast varying with depth. Geophys. Prosp., 44, 1525-1530.
RADHAKRISHNA MURTHY, I. V. and S. JAGANNADHA RAO, 1989. A Fortran 77 program for inverting gravity anomalies of two-dimensional basement structures. Computer. Geosci., 15, 1149-1156.
RADHAKRISHNA MURTHY, I. V., P. RAMARAO and S. JAGANNADHA RAO, 1990. The density difference and generalized programs for two- and three-dimensional gravity modeling. Computer. Geosci., 16, 277-287.
PAL, P. C., K. K. KHURANA and P. UNNIKRISHNAN,1979. Two examples of spectral approach to source depth estimation in gravity and magnetics. Paleogeoph., 117(78/79). DOI: https://doi.org/10.1007/BF00879978
RADHAKRISHNA MURTHY, I. V. and B. RAO, 1979. Gravity anomalies of two-dimensional bodies of irregular cross-section with density contrast varying with depth. Geophys. Prosp., 44, 1525-1530. DOI: https://doi.org/10.1190/1.1441023
RADHAKRISHNA MURTHY, I. V. and S. JAGANNADHA RAO, 1989. A Fortran 77 program for inverting gravity anomalies of two-dimensional basement structures. Computer. Geosci., 15, 1149-1156. DOI: https://doi.org/10.1016/0098-3004(89)90126-X
RADHAKRISHNA MURTHY, I. V., P. RAMARAO and S. JAGANNADHA RAO, 1990. The density difference and generalized programs for two- and three-dimensional gravity modeling. Computer. Geosci., 16, 277-287. DOI: https://doi.org/10.1016/0098-3004(90)90064-Z
RAMARAO, P. and RADHAKRISHNA MURTHY, I. V.,1989. Two Fortran 77 function subprograms to calculate gravity anomalies of bodies of finite and infinite strike length with the density contrast differing with depth. Computer. Geosci., 15, 1265-1277. DOI: https://doi.org/10.1016/0098-3004(89)90091-5
ROSAS-ELGUERA, J., L. FERRARI, V. H., GARDUÑO and J. URRUTIA-FUCUGAUCHI, 1996. Continental boundaries of the Jalisco block and their influence in the Pliocene-Quaternary kinematics of western Mexico. Geology, 24, 921-924. DOI: https://doi.org/10.1130/0091-7613(1996)024<0921:CBOTJB>2.3.CO;2
SERPA, L., S. SMITH, C. KATZ, C. SKIDMORE, R. SLOAN and T. PAVLIS, 1992. A geophysical investigation of the southern Jalisco block in the State of Colima, Mexico. Geofísica Internacional, 31, 475-492. DOI: https://doi.org/10.22201/igeof.00167169p.1992.31.4.1369
SIMPSON, R. W., R. C. JACHENS and R. J. BLAKELY, 1986. A new isostatic residual gravity map of the conterminous United States with a discussion on the significance of isostatic residual anomalies. J. Geophys. Res., 91, 8348-8372. DOI: https://doi.org/10.1029/JB091iB08p08348
SPECTOR, A. and F. S. GRANT, 1970. Statistical models for interpreting aeromagnetic data. Geophysics, 35, 293-302. DOI: https://doi.org/10.1190/1.1440092
TALWANI, M., J. L. WORZEL and M. LANDISMAN, 1959. Rapid gravity computations for two-dimensional bodies with application to the Mendocino submarine fracture zone. J. Geophys. Res., 64, 49-59. DOI: https://doi.org/10.1029/JZ064i001p00049
URRUTIA-FUCUGAUCHI, J. and R. MOLINA-GARZA,1992. Gravity modeling of regional crustal and upper mantle structure of the Guerrero terrane- 1. Colima graben and southern Sierra Madre Occidental, western Mexico. Geofísica Internacional, 31, 493-507. DOI: https://doi.org/10.22201/igeof.00167169p.1992.31.4.1370
URRUTIA-FUCUGAUCHI, J. and J. H. FLORES-RUIZ,1996. Bouguer gravity anomalies and regional crustal structure in central Mexico. Int. Geol. Rev., 38, 176-194. DOI: https://doi.org/10.1080/00206819709465330