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A review of recently active faults in Taiwan

Six faults associated with five large earthquakes produced surface displacements ranging from 1 to 3 m in the period 1906 through 1951. Four of the ruptures occurred in the western coastal plain and foothills, and two occurred in the Longitudinal Valley of eastern Taiwan. Maps are included showing the locations and dimensions of the displacements. The published geological literature probably would
Authors
Manuel G. Bonilla

Rutile and sphene in blueschist and related high-pressure facies rocks

Sphene and rutile are characteristic accessory minerals of blueschist facies metamorphic rocks. However, only sphene is present in the lowerr grade blueschist assemblages. In many areas of the world these blueschists pass into, or are in fault contact with, higher grade glaucophane schists, rutile-bearing amphibolites, and eclogites. The origin of the rutile may be related to a prograde metamorphi
Authors
M.C. Blake, Benjamin A. Morgan

Major chemical characteristics of Mesozoic Coast Range ophiolite in California

Sixty-four major element analyses of rocks representative of the Coast Range ophiolite in California were compared with analyses of other onland ophiolite sequences and those of rocks from oceanic ridges. The rocks can be classed in five groups harzburgite-dunite, clinopyroxenite-wehrlite, gabbro, basalt-spilite, and keratophyre-quartz keratophyre which on various diagrams occupy nonoverlapping fi
Authors
E. H. Bailey, M. C. Blake, Jr.

Fresh lunar impact craters: Review of variations in size

Thirty-three morphologic characteristics are reviewed for fresh lunar impact craters wide than1 km. Bar graphs express the way each characteristic varies with crater size. The features are grouped as crater structure, ejecta, and downhill flow features. Major structural transition occur at diameters of about 15 and 200 km. Details of the ejecta blanket, which include several kinds of lineations, d
Authors
Keith A. Howard

Lunar basin formation and highland stratigraphy

Multiring impact basins, formed after solidification of the lunar crust, account for most or all premare regional deposits and structures expressed in the lunar landscape and for major topographic and gravity variations. A fresh basin has two or more concentric mountain rings, a lineated ejecta blanket, and secondary impact craters. Crackled material on the floor may be impact melt. The ejecta bla
Authors
Keith A. Howard, D.E. Wilhelms, D. H. Scott

Origin of Franciscan melanges in Northern California

In northern California, chaotic Franciscan melange occurs beneath the overlying ophiolite and Great Valley Sequence. Identical melanges occur to the west, separating well-bedded, coherent Franciscan units that differ markedly in age. Detailed studies in several places indicate that these melanges mark the boundaries of imbricate thrust sheets, and they appear to occur at several discrete structura
Authors
M. Clark Blake, D. L. Jones

Geologic Exploration of Taurus-Littrow: Apollo 17 Landing Site

Apollo 17 landed in a deep graben valley embaying the mountainous highlands southeast of the Serenitatis basin. Impact-generated breccias underlie the massifs adjacent to the valley, and basalt has flooded and leveled the valley floor. The dark mantle inferred from orbital photographs was not recognized as a discrete unit; the unusually thick regolith of the valley floor contains a unique high con
Authors
W.R. Muehlberger, R. M. Batson, E.A. Cernan, V. L. Freeman, M.H. Haitt, H. E. Holt, Keith A. Howard, K.B. Jackson, V.S. Larson, J.J. Reed, J. J. Rennilson, H.H. Schmitt