The Middle Rio Grande Basin: Historical Descriptions and Reconstruction
CHAPTER 4 THE MIDDLE RIO GRANDE BASIN: HISTORICAL DESCRIPTIONS AND RECONSTRUCTION This chapter provides an overview of the historical con- The main two basins are flanked by fault-block moun- ditions of the Middle Rio Grande Basin, with emphasis tains, such as the Sandias (Fig. 40), or volcanic uplifts, on the main stem of the river and its major tributaries in such as the Jemez, volcanic flow fields, and gravelly high the study region, including the Santa Fe River, Galisteo terraces of the ancestral Rio Grande, which began to flow Creek, Jemez River, Las Huertas Creek, Rio Puerco, and about 5 million years ago. Besides the mountains, other Rio Salado (Fig. 40). A general reconstruction of hydro- upland landforms include plateaus, mesas, canyons, pied- logical and geomorphological conditions of the Rio monts (regionally known as bajadas), volcanic plugs or Grande and major tributaries, based primarily on first- necks, and calderas (Hawley 1986: 23–26). Major rocks in hand, historical descriptions, is presented. More detailed these uplands include Precambrian granites; Paleozoic data on the historic hydrology-geomorphology of the Rio limestones, sandstones, and shales; and Cenozoic basalts. Grande and major tributaries are presented in Chapter 5. The rift has filled primarily with alluvial and fluvial sedi- Historic plant communities, and their dominant spe- ments weathered from rock formations along the main cies, are also discussed. Fauna present in the late prehis- and tributary watersheds. Much more recently, aeolian toric and historic periods is documented by archeological materials from abused land surfaces have been and are remains of bones from archeological sites, images of being deposited on the floodplain of the river.
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