The first geologic map of New Mexico Spencer G. Lucas, New Mexico Museum of Natural History and Science, 1801 Mountain Road NW, Albuquerque, New Mexico 87104 Introduction 2), and Kues (1985a, fig. 11; 1985b, fig. 7) the United States that placed him among a reproduced parts of the map in black and competitive group of compilers of such In 1858 the French geologist Jules Marcou white. DeFord (1972) also discussed some maps, including James Hall, Edward (1824–1898) published the first geologic aspects of Marcou’s map. Here, I re-pub- Hitchcock, and Henry Rogers, who map of New Mexico. This map was a prod- lish Marcou’s entire map in color at about worked in the decades immediately pre- uct of Marcou’s 1853 traverse of the New half of its original size (Fig. 2). My text is in ceding the Civil War (Nelson, 1999). Mexico Territory as the geologist of the four parts—a brief overview of the context Indeed, as Goetzmann (1959, p. 311) Whipple expedition to determine a route of Marcou’s map, an explanation of the noted, Marcou “published the first geolog- for a transcontinental railroad (Fig. 1; geologic units Marcou mapped, a summa- ic map of the West, which made him a con- Kues, 1985a). Marcou’s map (Fig. 2) is not ry of the map, and a brief evaluation of its troversial figure in American scientific cir- a complete geologic map of the territory strengths and weaknesses. cles for most of his later career.” Much of (nor of the current state)—it encompasses the controversy focused on Marcou’s work about one degree of latitude around 35°N. in New Mexico, where he identified vast

Nevertheless, it was the first map explicit- Context of Marcou’s map expanses of Triassic and Jurassic strata, ly titled “Geological Map of New Mexico.” particularly under the southern High It predates, by about 70 yrs, the first pub- In 1853 Marcou served as chief geologist of Plains (e.g., Goetzmann, 1959; Kues, 1985b; lished, statewide maps of Ellis (1925) and the Army Corp of Topographical Engin- Nelson, 1989, 1999). Darton (1928). Indeed, Blake’s (1856) geo- eers’ Survey of the 35th Parallel Route for logic map of Marcou’s route is a crude the Pacific Railroad, under the leadership Marcou’s stratigraphy effort based on Marcou’s data by some- of Lieutenant Amiel Whipple (Goetzmann, body who never visited the state (Kues, 1959). This survey was authorized and Born in Salins, France, near the Jura Moun- 1985a). funded by the U.S. Congress and traversed tains, Marcou first studied mathematics Marcou’s map is little known to geolo- from Fort Smith, Arkansas, to Los Angeles, and then trained in geology. His outstand- gists working in New Mexico today, large- California, between July 1853 and March ing talent brought him a professorship in ly because of the rarity of the book in 1854 (Fig. 1). As survey geologist, one of mineralogy at the Sorbonne in 1846 and a which it first appeared as an approximate- Marcou’s (1853, p. 58) primary goals was curatorship (in fossil conchology) at the ly 63 x 14 cm (25 x 6 inch) color foldout “to synchronize the sedimentary rocks of Jardin de Plantes in 1847. He subsequently (Marcou, 1858, pl. 8). Kelley and Northrop America with those of Europe.” The results traveled to the United States, married into (1975, fig. 8), Hook and Cobban (1979, fig. of Marcou’s efforts were geologic maps of a wealthy family, and ultimately spent

84 NEW MEXICO GEOLOGY August 2001 Marcou’s map employs eight carto- graphic units, three of igneous or meta- California Oklahoma morphic rocks and five of sedimentary rocks. In temporal order (oldest to Los Fort youngest), they are: Angeles Arizona New Smith (1) Granite, Gneiss, Porphyry, etc. (G); Mexico (2) Carboniferous (M for Mountain Lime- stone); (3) New Red Sandstone (R); Texas (4) Jurassic (J); (5) Cretaceous (C); (6) Volcanos (sic) (V); Marcou’s (7) Trap (T); and Map (8) Quaternary (O).

FIGURE 1—Route of the Whipple expedition of 1853, and area included in FIGURE 2—Jules Marcou’s geologic map of Marcou’s (1858) geological map of New Mexico (Fig. 2; after Goetzmann, 1959). New Mexico (from Marcou, 1858, pl. 8).

most of his later life in this country (Lurie, above). Thus, his 1858 text abounds in Granite, gneiss, porphyry, etc. 1974). In reviewing Marcou’s geologic map close comparison of the European and of New Mexico, we should realize that, North American rock successions, tinged Based on his observations in the Sangre de although Marcou was an all-round geolo- with clear satisfaction when a close corre- Cristo and Sandia Mountains, Marcou gist in the best tradition of his times, his spondence/correlation is established. This (1858, pp. 20–21) noted that “masses of research and expertise focused on sedi- is well reflected by Marcou’s ready use of Granite…form the centre of the line of dis- mentary rocks and fossils. Indeed, Sarjeant European names such as “Mountain location of the Rocky Mountains.” He fur- (1980, p. 1648) appropriately labeled Limestone” and “New Red Sandstone” for ther observed (p. 21) that in the Sandia Marcou a “stratigrapher, structural geolo- New Mexican strata. And, where he Mountains (Tijeras Canyon) he encoun- gist and invertebrate paleontologist.” judged lithologic similarity to be less close, tered a succession of “quartzose metamor- Like most European geologists of the Marcou proposed direct correlation of the phic rocks,” then “serpentine,” and then early nineteenth century, Marcou expected New Mexican units to their European granite. However, Marcou provided no to find a close correspondence between the equivalents; for example, his correlation of further information on these basement rock formations already delineated in the marine Cretaceous strata of north-cen- rocks, probably because his interests and western Europe and those in North tral New Mexico to the European “White expertise lay elsewhere. America (see quote from Marcou, 1853 Chalk.”

August 2001 NEW MEXICO GEOLOGY 85 Carboniferous Jurassic is mostly the Entrada Sandstone, river….” Marcou, however, offered no now recognized across the state and detailed description of these rocks, which Based on what he’d seen of the European known to be of Middle Jurassic age. he probably assumed to be very young section, Marcou would have expected the because of their coarse-grained and uncon- New Mexican Carboniferous to consist of a solidated textures. lower, limestone-dominated interval and Cretaceous an upper, coal-bearing interval. Marcou Marcou gave no thickness for these rocks applied the British terms “Mountain and described them (p. 22) as mostly a Summary of the map Limestone” (in Europe these strata form white, friable sandstone that is horizontal- Four pages of explanatory text (Marcou, mountains) and “Coal Measures” to these ly stratified with index fossils of the 1858, pp. 54–57) accompany Marcou’s geo- rocks. In New Mexico, Marcou’s most Cretaceous, including Inoceramus, “Ammo- logic map. This text begins with a short detailed examination of these rocks was in nites,” and Scaphites. The shark tooth found introduction, concluded by a disclaimer: the Sandia Mountains (Tijeras Canyon) near Galisteo in these strata that Marcou “This map must be regarded as a first essay where he described them as “grayish blue named Ptychodus whipplei was the first ver- upon a country about which the geological limestone, containing a great quantity of tebrate fossil described from New Mexico. notions have hitherto been very vague, and fossils” (p. 20). Above them are a “black Marcou correlated the New Mexican I publish it only as a first attempt upon a slate” or “black schistose clay” assigned to Cretaceous to the White Chalk (Craie terra incognita.” The remaining text is struc- the “coal measures” but not mapped sepa- Blanche) of France. He also stated (p. 22) tured as a narrative organized by Marcou’s rately (p. 20). Marcou states the Mountain that “the discordance of stratification of 38 camps in New Mexico and the traverses Limestone in New Mexico has a mean the Upper Cretaceous of New Mexico, between these camps. Here, I divide thickness of 700 ft (p. 21). His assessment with all the sedimentary rocks found there, Marcou’s map into three geographic por- of the fossils he collected and described indicates that this formation was deposit- tions—east-central, north-central, and (mostly brachiopods) led him to incorrect- ed after the principal dislocation of the west-central New Mexico. ly assign the New Mexican Mountain Rocky Mountains, which took place at the Limestone to the Early Carboniferous. But, end of the American Jurassic period.” This East-central New Mexico as Newberry (1861) first determined, and repudiation of basic principles led Marcou Marcou traversed east-central New Mexico as stressed by Kelley and Northrop (1975, to an erroneous conclusion, as the from east to west, just north of the 35th pp. 35–44), who reviewed Marcou’s Cenozoic uplift of the Rocky Mountains parallel, and stayed at ten camps. The geo- Carboniferous fossils in detail, they are all postdates the Cretaceous strata that are, in logic map across this traverse identifies Pennsylvanian in age. part, dislocated by the Rocky Mountain only two stratigraphic units—lowlands of orogeny, not the reverse! New Red Sandstone and uplands of New Red Sandstone Jurassic strata. Volcanos (sic) Marcou’s observations at Pyramid During the early 1800s British geologists Mountain (pp. 18–21; Fig. 3), between referred to most of the strata between the Marcou mapped volcanic rocks across camps 4 and 5, proved critical to these Carboniferous and Lower Jurassic (Liassic) large parts of north-central and west-cen- determinations (DeFord, 1972; Kues, as the New Red Sandstone (Wilmarth, tral New Mexico. His text offers brief 1985b). Here, Marcou collected gryphaeid 1925). In Europe, these are largely Permian descriptions of volcanoes near Galisteo, bivalves from shales near the butte sum- and Triassic red beds, with some intervals San Felipe Pueblo, Mount Taylor, and east mit. Gryphea is a characteristic Jurassic of evaporites and marine limestone. of Zuni Pueblo. He was particularly bivalve in Marcou’s native Jura Mountains Marcou applied the term New Red impressed by “immense overflowings of region, so he reasonably inferred a Jurassic Sandstone in a similar way in New Mexico, lava” (p. 22) in west-central New Mexico, age for the New Mexico fossils and but there is no evidence that he considered and noted that the lava flows “are destitute assigned a Jurassic age to all of the strata any of these strata to be Permian (or Dyas of vegetation, and give to the country, defending the Llano Estacado and its ero- in age, a term Marcou preferred to where they are found, an arid and desolate sional outliers. But, these fossils are not Permian; Marcou, 1892) in age. Marcou aspect, named by the Mexicans, very true Gryphaea and instead belong to a assigned the New Mexican New Red appropriately, Mal Pais” (pp. 22–23). closely related Early Cretaceous taxon, Sandstone a Triassic age and described it now called Texigryphaea. Thus, the shale as mostly red sandstone, but including Trap strata at Pyramid Mountain are actually of beds of gypsum and dolomite. According Cretaceous age, and Marcou’s error engen- to Marcou, these strata are 4,000–5,000 ft Marcou used the term trap to refer to dikes dered a lengthy debate that was never thick in New Mexico (p. 10). formed by dark-colored igneous rocks. He resolved in his lifetime (Lurie, 1974; Kues, mapped such dikes in the Galisteo area 1985b). Marcou’s assignment of the under- Jurassic and near Fort Defiance on the western lying rocks to the Triassic lacked a paleon- edge of the map. Marcou offered no dis- tological basis; instead, stratigraphic posi- Marcou’s identification of Jurassic strata in cussion of these rocks, but did note near tion and similarity to the nonmarine New Mexico was his most controversial Galisteo (p. 56) “a trap dyke, direction 30° Keuper (Upper Triassic) strata of Europe conclusion (DeFord, 1972; Kues, 1985b). east-east-north and 30° west-west-south, provided the principal basis for Marcou’s Marcou stated that these rocks are as much cutting through the strata of the New Red determination. as 400 ft thick on the Llano Estacado in Sandstone.” From Camp 1 (near present San Jon) to eastern New Mexico, where they are most- Camp 7 (near present-day Santa Rosa), the ly white and yellow sandstone, minor Quaternary lowland country is largely Upper Triassic limestone, and a “blue clay” with a charac- red beds (now Chinle Group). But as teristic Jurassic invertebrate fauna that Marcou termed the youngest sediments he Marcou traversed northwestward, up the includes the bivalves “Gryphaea” (now saw in New Mexico Quaternary (in the Pecos River (Camps 8–10), he failed to rec- termed Texigryphaea) and Ostrea (p. 20). text, “Quarternary” [sic]). He noted (p. 22) ognize, as distinct, the underlying Permian This “blue clay,” the Tucumcari Shale of “the plain of the Rio Grande del Norte, strata. Indeed, on Marcou’s map, all the current usage, is now assigned an Early where the Granite is found covered with nonmarine red beds are New Red Cretaceous age. The “white and yellow Drift and Alluvium, which form the whole Sandstone, including strata now distin- sandstone” Marcou assigned to the plain as far as the right bank of the guished as Permian (Abo, Yeso, and

86 NEW MEXICO GEOLOGY August 2001 Glorieta Formations), Triassic (Moenkopi Formation and Chinle Group), and Eocene (Diamond Tail and Galisteo Formations). And, at some locations (notably Tijeras Canyon in the Sandia Mountains), Marcou even included in the New Red Sandstone strata now known to be Jurassic. North-central New Mexico North-central New Mexico encompasses the area from Marcou’s camps 11 (Galisteo River) to 26 (just southwest of Albuquer- que). Marcou correctly identified Creta- ceous strata just east of Galisteo, based in large part on their fossil content, which included inoceramid bivalves and ammonites known to him to be Late Creta- ceous fossils in Europe. He also identified volcanic rocks of the Gold Hills–Ortiz Mountains, which are now known to be mid-Cenozoic (primarily Oligocene) in age. Understandably, having no way to determine precise ages, Marcou included basalts of late Cenozoic age he encoun- FIGURE 3—Mesozoic strata of Pyramid Mountain viewed from the east. tered just west of the Rio Grande (Cerros del Rio volcanic field, Santa Ana basalts) in the same cartographic unit of volcanic Albuquerque westward across the Rio his map the Zunis are similar to the Jemez rocks. Furthermore, lack of attention to Puerco, south of Mount Taylor, around the Mountains—a linear welt of granite lithologic detail probably also explains southeastern edge of the Zuni Mountains flanked on both sides by Carboniferous why Marcou included all igneous rocks, and on to El Morro, Zuni Pueblo, and what New Red Sandstone, and Jurassic strata. In other than a few dikes, in one map unit. is now Arizona. On this traverse, Marcou fact, the basement-cored Zunis are overlain Marcou identified the relatively young assigned the rocks to units already encoun- to the northeast by sedimentary strata (as sediments along the Rio Grande valley tered to the east. Marcou depicts, though very little (now mostly Santa Fe Group of Miocene– He thus identified the Mount Taylor and Carboniferous rock is actually present) but Pleistocene age) as Quaternary. Marcou’s Zuni–Bandera volcanic fields, assigning separated on the southwest from Mesozoic mapping of these sediments differentiates them to his general cartographic unit strata by faults that dip to the west-south- the Española basin outcrop belt from the “Volcanos.” This again underscores Mar- west, away from the range. Limestone- Albuquerque basin outcrop belt and even cou’s expertise in sedimentary rocks and dominated strata of the Permian San shows the northward right shift of the rift fossils, for he failed to differentiate the Andres Formation in the Zuni Mountains basins, although Marcou attributed no sig- very young lava flows in west-central New evidently were mistaken by Marcou for his nificance to these patterns. Mexico from the older and lithologically “Mountain Limestone.” After Marcou reached Albuquerque, he different igneous rocks in the Galisteo area went east and northeast through the of north-central New Mexico. Further- Sandia Mountains and up to Pecos in the more, Marcou’s map shows a broad area of Conclusion—strengths and Sangre de Cristo Mountains (“Rocky volcanic rocks east of Mount Taylor weaknesses of the map Mountains” on Marcou’s map). In the extending east of the Rio Puerco. No such Sandias he first encountered rocks he cor- volcanic rocks exist; probably they are an The great strength of Marcou's map is its rectly identified as Carboniferous, assign- unwarranted extrapolation by Marcou of accurate depiction of the basic geologic ing them (based largely on their fossil con- the Albuquerque volcanoes and basalts structure of part of New Mexico—south- tent) to the Mountain Limestone, which in westward to meet the Mount Taylor field. ern High Plains mantled by largely flat- current terminology would be Missis- In west-central New Mexico, Marcou lying Mesozoic strata, basement-cored sippian (they are actually Pennsylvanian). identified vast expanses of Jurassic strata, block-faulted mountains in central New Marcou recognized the granitic cores of the mostly the yellow cliff-forming sandstones Mexico draped with Carboniferous marine Sandia and Sangre de Cristo Mountains, now called the Entrada Sandstone. A sig- strata, Rio Grande valley filled with young and their principal sedimentary cover as nificant omission is Marcou’s failure to Cenozoic sediments, and southern Colo- marine strata of Carboniferous age. He identify Cretaceous strata in west-central rado Plateau covered in large part by thus reasonably (but incorrectly) extrapo- New Mexico. Indeed, in his text (p. 57) he Jurassic strata and extensive volcanic lated this structure onto the Jemez claims to have found Gryphaea dilatata var. fields. The most significant weaknesses of Mountains, which he did not visit. tucumcarii near Camp 30 (near present-day the map are its evident errors: misidentifi- Doubtless, if he had, he would have imme- Cubero), which must be an error for one of cation of Lower Cretaceous strata on the diately recognized their volcanic origin. the common and superficially similar southern High Plains as Jurassic, incorrect Indeed, the eastern flank of the Jemez Cretaceous bivalves now assigned to basic structure of the Jemez and Zuni Mountains as depicted by Marcou—broad Pycnodonte (though long assigned to Mountains, and failure to identify outcrop belts of Carboniferous, New Red Gryphaea). Cretaceous strata in west-central New Sandstone, and Cretaceous—is one of the Marcou’s map gives little or no hint of Mexico. Yet, in spite of its flaws, Marcou's more significant errors on his map. the presence of the San Juan Basin, which geologic map of New Mexico represents a in its broadest sense begins on the north- remarkable first effort. Thereby, it not only West-central New Mexico eastern flank of the Zuni Mountains. laid a foundation for subsequent work, but Here, west-central New Mexico refers to Indeed, Marcou’s portrayal of the Zuni the controversy it engendered drew Marcou’s camps 27–38, a traverse from Mountains is not completely correct. On greater geologic attention to New Mexico.

August 2001 NEW MEXICO GEOLOGY 87 Acknowledgments. Bonnie Roach made Goetzmann, W. H., 1959, Army exploration in the two reports on the prairies of Arkansas and possible access to an original copy of American West 1803–1863: University of Texas, the Rocky Mountains of New Mexico, and Marcou (1858), Daniel Weissman produced Nebraska Press, Lincoln, 489 pp. the Sierra Nevada of California, originally made Hook, S. C., and Cobban, W. A., 1979, Prionocyclus for the United States government: Zürcher and an electronic copy of Marcou’s map, and novimexicanus (Marcou)—common Upper Creta- Furrer, Zurich, 144 pp. Barry Kues, Peter Lessing, Clifford Nelson, ceous guide fossil in New Mexico: New Mexico Marcou, J., 1892, On the classification of the Dyas, and Linda Zellmer provided helpful com- Bureau of Mines and Mineral Resources, Annual Trias, and Jura in northwest Texas: American ments on an earlier version of the manu- Report 1977–78, pp. 34–42. Geologist, v. 10, pp. 369–377. script. Kelley, V. C., and Northrop, S. A., 1975, Geology of Nelson, C. M., 1989, Geologic maps of American Sandia Mountains and vicinity, New Mexico: West: Hall vs. Marcou (abs.): 28th International New Mexico Bureau of Mines and Mineral Geological Congress, Washington, DC, Abstracts, References Resources, Memoir 29, 135 pp. v. 2, pp. 504–505. Kues, B. S., 1985a, Early geological explorations in Nelson, C. M., 1999, Toward a reliable geologic map Blake, W. P., 1856, Report of the geology of the northeastern and east-central New Mexico; in of the United States, 1803–1893; in Carter, E. C., II route, no. 1—General report upon the geological Lucas, S. G., and Zidek, J. (eds.), Santa Rosa– (ed.), Surveying the record—North American sci- collections; in Reports of explorations and sur- Tucumcari region: New Mexico Geological Soci- entific exploration to 1930: Memoirs of the veys to ascertain the most practicable and eco- ety, Guidebook 36, pp. 103–118. American Philosophical Society 231, pp. 51–74. nomical route for a railroad from the Mississippi Kues, B. S., 1985b, Stratigraphy of the Tucumcari Newberry, J. S., 1861, Geological report; in Ives, J. River to the Pacific Ocean, vol. 3, part IV: U.S. area—a historical account; in Lucas, S. G., and C., Report upon the Colorado River of the West: 33rd Congress, Second Session, Senate Executive Zidek, J. (eds.), Santa Rosa–Tucumcari region: U.S. 36th Congress, First Session, Senate Document 78 and House Executive Document 91, New Mexico Geological Society, Guidebook 36, Executive Document 77 and House Executive pp. 121–164. pp. 119–140. Document 90, 154 pp. Darton, N. H., 1928, Geologic map of New Mexico: Lurie, E., 1974, Marcou, Jules; in Gillispie, C. C. Sarjeant, W. A. S., 1980, Geologists and the history Washington, DC, U.S. Geological Survey, scale (ed.), Dictionary of scientific biography, volume of geology—an international bibliography from 1:500,000. 9: Charles Scribner and Sons, New York, pp. the origins to 1978. Volume 3: Arno Press, New DeFord, R. K., 1972, Marcou in east-central New 99–101. York, 489 pp. Mexico; in Kelley, V. C., and Trauger, F. D. (eds.), Marcou, J., 1853, A geological map of the United Wilmarth, M. G., 1925, The geologic time classifica- East-central New Mexico: New Mexico Geolo- States, and the British Provinces of North Amer- tion of the United States Geological Survey com- gical Society, Guidebook 23, pp. 65–71. ica, with an explanatory text, geological sections, pared with other classifications accompanied by Ellis, R. W., 1925, Geologic map of the state of New and plates of the fossils which characterize the the original definitions of Era, Period, and Epoch Mexico: University of New Mexico, Albuquer- formations: Gould and Lincoln, Boston, 92 pp. terms: U.S. Geological Survey, Bulletin 769, 138 que, scale 1 inch = 12 mi. Marcou, J., 1858, Geology of North America, with pp.

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