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    A Trail Guide to the Dominguez – Velez de Escalante Expedition 1776

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    In 1939, Herbert E. Bolton stated a need for a synthesizing map of the Dominguez - Velez de Escalante route through the four states of New Mexico, Colorado, Utah, and Arizona. Dr. Bolton urged that a joint effort be undertaken between state and government agencies to establish an Escalante Way through the four states to commemorate the historic trek. The Trail Guide to the Dominguez - Velez de Escalante Expedition 1776 is an answer to the Challenge given by Herbert Bolton. It is essentially a set of maps, accurately drawn, simplified for lay read­ ing and enlivened by supporting text. This trail guide is separated into three main sections: 1) The Beginning, 2) The Ending, and 3) The Trail. 1) The Beginning. The Dominguez-Escalante expedition resulted as one of Spain\u27s attempts to shore up her northwestern borders against foreign encroachment by the French, Russians and British. A route to Monterey from the northern Spanish stronghold, Santa Fe, would consolidate the Spanish domination of the Southwest and enhance commercial ties with important sources of supply. For this attempt two Franciscan priests were selected to lead eight other adventurers over two thousand miles in an attempt to find a practicable route to the California coast. 2) The Ending. The results of what then was thought to be failure to secure a viable route west were important to subsequent exploration and administrative problems both to the crumbling Spanish colonies and to American expansion. Both the journal kept by Escalante and the map drawn by Don Bernardo Miera had influence beyond their time and intent. 3) The Trail. The last section of the Guide is a narrative of the trail keyed to accompanying detailed maps (24) of the route through the four states of New Mexico, Colorado, Utah, and Arizona. The narrative blends the experience of both the Spanish party in 1776 and the author in 1973. The maps show the route taken by the Spaniards superimposed upon modern landmarks such as cities, highways and dams. Each campsite made by the party in 1776 is shown and names given prominent geographical features by the Spanish travelers at the time they passed through the country are also given. Where the modern place and feature names have changed in the ensuing period, both have been given on the maps

    Base-metal deposits of the Cordillera Negra, department of Ancash, Peru

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    The Cordillera Negra, the westernmost range in the Departamento de Ancash, is just north of the central mineral province of Peru. Within several kilometers of its crest and along a length of 140 kllometers are more than 60 base-metal deposits that total several hundred veins. These deposits were studied in 1947 by the Umted States Geological Survey m cooperation with the Instituto Geológico del Perú. Ores in the deposits contain principally the sulfides of lead and zinc and, in some places, copper, one mine produces antimony ore and another, silver. Basemetal production is wholly dependent on silver content of ore, hence only argentiferous sulfides of lead or copper are sought and sphalerite, which contains little or no silver, is discarded. At the time of our examination, three mines were operated on a comparatively large scale, but one of these subsequently closed, in 1947 the three produced about 37,000 tons of ore, which was concentrated in flotation plants. In the same year fifteen small mines produced probably less than 1,000 tons of ore, which was concentrated by hand cobbing or hand jigging. The deposits in the Cordillera Negra have been worked for many years, so the majority of both large and small active mines now contain small reserves. The reserves of most of the abandoned mines could not be estimated, owing to inaccessibility of their workings. The oldest rocks that can be dated in the Cordillera are Cretaceous in age An estimated 2,200-meter-thick sequence of sedimentary rocks of Early Cretaceous age consists predominantly of nonmarine sandstone and shale but includes several coal beds, a thin unit of limestone, and, toward the top of the sequence, a unit of tuff. These rocks are overlain by Albian to Turonian limestone, estimated to be from 200 to 400 meters thick. This sedimentary sequence is overlain by a sequence of layered volcanic rocks, possibly in part of Late Cretaceous age but mostly of Tertiary age The volcanic rocks are estimated to be at least 1,000 meters thick, lava and agglomerate are the most common rocks, but some tuff and a few beds of nonvolcanic sediments are included in the sequence. Most of the -lava and the agglomerate is porphyritic andesite and most of the tuff is rhyolite. The volcanic sequence can be divided into two groups a lower group includes layers that are moderately closely folded, an upper group includes those that are only slightly folded. The sedimentary and volcanic rocks are intruded by granodwntic and granitic batholiths and stocks, by porphyritic andesite and rhyolite stocks and plugs, and by sills and dikes ranging from pegmatite to andesite in composition. Some sedimentary rock has been converted to andalusite schist near contacts with the batholiths or the larger gramtic stocks. The layered rocks have been deformed during two periods of major orogeny, the first of possible Late Cretaceous or very early Tertiary age, and the second of possible early Tertiary age. Each is marked by a conspicuous unconformity. The lower unconformity is between the sedimentary sequence and the folded lower volcanic group, and the upper is between the folded lower volcanic group and the slightly folded upper volcanic group. Plutonic intrusion of granodiorite and granite and shallow-seated intrusion of porphyry seems to have occurred in the Tertiary Strata of the sedimentary sequence are closely folded and those of the lower volcanic group are moderately closely folded, and strata of both are broken by thrust and reverse faults. Axial planes of folds dip steeply and strike generally N 30° W, parallel to the structural trend of the Andean Cordillera in this part of Peru. Open folds and warps characterize deformation in the upper volcanic group, and are accompanied by steeply dipping normal and reverse faults of small displacement. Only limited regional metamorphism of the older rocks resulted during orogenesis, slaty cleavage is found in some shale. Most deposits are minerahzed fractures containig pyrite, galena, and sphalerite in a gangue of quartz and carbonate, other minerals that may be present are arsenopyrite, chalcopyrite, enargite, or tetrahedrite. Other deposits are quartzpyrite veins, and in some the sulfides commonly are marmatite, pyrrhotite, and pyrite. One vein contains stibnite and pyrite in quartz. Either primary or secondary silver minerals occur in all deposits, in some in sufficient quantities to repay fairly high mining costs, gold also is present in many deposits but generally in insignificant amounts. Nearly all minerals were deposited as fissure-fillings, but some replaced wall-rock on a small scale in several veins. Alteration in most deposits was slight and altered zones are confined to adjacent wall-rock. Several deposits, however, occur in widespread altered zones. Textures and the prevalence of low-temperature minerals suggest that the deposits were formed at shallow depths, and that the vertical range of ore deposition was small. Minining discloses the maximum range was almost 600 meters At several mines zoning is well developed in both vertical and horizontal dimensions, in distances as small as 200 meters. The type of minerals, degree of crystalhnity, and vein structures indicate that the veins formed at shallow depths under conditions of moderate to low temperature and pressure, and thus can be classed as ranging from mesothermal to epithermal. Although 600 meters is about the maximum vertical range of strongly mineralized deposits, most veins do not reach this depth Veins range in length from several meters to 2.5 kilometers, and range in width from several centimeters to many meters. Lenticular ore shoots of irregular sizes and shapes occupy only small parts of most veins, this precludes any great increase in the rate at which ore is mined

    Responses to Missionization at Missions San Antonio, San Carlos, and Soledad

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    The converted populations of Missions San Antonio, San Carlos, and Soledad never participated in an organized revolt against the Franciscan missionaries like other populations did throughout the American West. Yet, the converts were subjected to the same methods of control by the Franciscan missionaries. Because the tribes of the Monterey area were small and relatively unconnected to their neighbors, the groups could not organize as one once they were on the missions. For these missions individual revolt was how the converts responded to the types of control that they were subjected to. This paper analyzes the common threads in the violent revolts throughout the American West and demonstrates that these were present at Missions San Antonio, San Carlos, and Soledad. This paper then demonstrates that the neophytes on these missions did revolt, just on an individual as opposed to a group basis

    New Mexico and the Pimería Alta

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    Colonialism and the process of state expansion into new territories far from the capitol and mother country have occurred for thousands of years across the globe. Within the American Southwest, colonial encounters and the processes of colonialism played out in notably divergent manners through time and space. The chapters in New Mexico and the Pimería Alta: The Colonial Period in the American Southwest, focus on the two major areas of the Southwest that witnessed the most intensive and sustained colonial encounters: the New Mexico Colony and the Pimería Alta. Although these broad areas share a similar early colonial history, the particular mix of players, socio-historical trajectories, and social relations within each area both led to, and were transformed by, markedly diverse colonial encounters. Understanding these different mixes of players, history, and social relations provides the foundation for conceptualizing the enormous changes wrought by colonialism throughout the region
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