This file was created by the TYPO3 extension publications --- Timezone: CEST Creation date: 2026-05-14 Creation time: 13:04:42 --- Number of references 15 article Avendaño2023 Lake Chalco, in Central Mexico, has a long diatom record which provides an excellent opportunity to document the biotic and hydrological responses of this ecosystem to orbital- and millennial-scale climatic variability during the last 150 ka. Detrended correspondence analysis was used to evaluate the ecological turnover and to identify diatom species associations throughout the sequence. Millennial-scale climatic fluctuations were identified as peaks in freshwater (mostly small Fragilariaceae spp.) or as peaks in salt-tolerant species. At orbital scales, species turnover involved changes between freshwater assemblages dominated by Stephanodiscus spp. – small Fragilariaceae spp. – Cocconeis placentula, present during low-evaporation, cool intervals [late Marine Isotope Stage (MIS)6, MIS5d, MIS2] against salt-tolerant taxa, dominated by Stephanocyclus and Cyclotella spp., in higher evaporation, higher salinity conditions (MIS5e, MIS5c–a, MIS4, MIS3, early MIS1). Comparatively, MIS6 and MIS5d seem to have been cooler (~ −6 to −7 °C) and wetter than MIS2 (~ − 4 to −5 °C). In contrast, MIS5e and early MIS1 (11.5–6 ka) had similar warmer, low lake level, saline conditions. In addition, MIS5 was a period of intense climatic change associated with wide-amplitude orbital forcing that favored a Stephanocyclus–Cyclotella spp. ecological succession (S. meneghinianus, C. tlalocii, C. poyeka, S. quillensis). In contrast, smaller temperature changes were inferred during MIS4 and MIS3. © 2023 The Authors Journal of Quaternary Science Published by John Wiley & Sons Ltd. 2023 English 02678179 10.1002/jqs.3507 Journal of Quaternary Science John Wiley and Sons Ltd Posgrado de Ciencias de la Tierra, Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico; Laboratorio de Paleolimnología, Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico; Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, Mexico https://www.scopus.com/inward/record.uri?eid=2-s2.0-85148423211&doi=10.1002%2fjqs.3507&partnerID=40&md5=0762f5ecd06019a136b1ec7e61275950 cited By 0 D. Avendaño M. Caballero B. Ortega-Guerrero S. Lozano-García article Chávez-Lara2022 We present a palaeohydrological reconstruction of Lake Chalco from 70 to 11.5 ka BP based on ostracod records consisting of three species: Limnocytherina axalapasco, Candona patzcuaro, and Cypridopsis vidua. Overall, the presence of these species helped investigate Lake Chalco water level fluctuations, and thus water salinity variations. Moreover, this work helped improve our knowledge of L. axalapasco and Candona alchichica, two endemic species of Central Mexico, the latter of which was replaced by C. patzcuaro after the cold and dry MIS4. Five ostracod zones reflect the main environmental changes that occurred during the Late Pleistocene. During 70–62 ka BP (Zone 5), shallow and very variable salinity conditions were inferred with a possible occupancy of submerged macrophytes. The Lake Chalco water level increased from 62 to 49 ka BP (Zone 4) and relatively less saline conditions were inferred. The warmer period from of 49–39 ka BP (Zone 3) was characterised by lower lake levels and a gradually increasing salinity. The evaporation rates continued to increase during 39–27 ka BP (Zone 2). However, a higher runoff input helped maintain a relatively high lake level. Later on, cold and dry conditions from 27 to 11.5 ka BP (Zone 1) inhibited the ostracod occupancy in Lake Chalco. © 2022 Elsevier Ltd 2022 English 08959811 10.1016/j.jsames.2022.103944 Journal of South American Earth Sciences 119 Elsevier Ltd Instituto de Geofísica, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, CP, Ciudad de Mexico, 04510, Mexico; Instituto de Geología, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, CP, Ciudad de Mexico, 04510, Mexico; Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, CP, Ciudad de Mexico, 04510, Mexico environmental change; evapotranspiration; ostracod; paleohydrology; Pleistocene; salinity; warming; water level, Lake Chalco; Mexico [North America] https://www.scopus.com/inward/record.uri?eid=2-s2.0-85137371288&doi=10.1016%2fj.jsames.2022.103944&partnerID=40&md5=13adccdbed3b5867d03da3f6de5c5abc cited By 2 C.M. Chávez-Lara S. Lozano-García B. Ortega-Guerrero D. Avendaño M. Caballero-Miranda article SardarAbadi2022 Understanding the moisture history of low latitudes from the most recent glacial period of the latest Pleistocene to post-glacial warmth in continental tropical regions is hampered by the lack of continuous time series. We conducted downhole spectral gamma (γ) ray and magnetic susceptibility logs over 300 m of lacustrine deposits of Lake Chalco (Mexico City) to reconstruct an age-depth model using an astronomical and correlative approach, and to reconstruct long-term moisture availability. Our results suggest that the Lake Chalco sediments contain several rhythmic alternations with a quasi-cyclic pattern comparable to the Pleistocene benthic stack. This allows us to calculate a time span of about 500,000 years for this sediment deposition. We developed proxies for moisture, detrital input, and salinity, all based on the physical properties of γ-ray spectroscopy and magnetic susceptibility. Our results indicate that Lake Chalco formed during Marine Isotope Stage 13 (MIS13) and the lake level gradually increased over time until the interglacial MIS9. Moisture content is generally higher during interglacials than during glacials. However, two periods, namely MIS6 and MIS4, have higher moisture contents. We developed a model by comparing the obtained moisture proxy with climatic drivers, to understand how different climate systems drove effective moisture availability in the Chalco sub-basin over the past 500,000 years. Carbon dioxide, eccentricity, and precession are all key drivers of the moisture content of Lake Chalco over the past 500,000 years. © 2022 The Authors 2022 English 02773791 10.1016/j.quascirev.2022.107739 Quaternary Science Reviews 294 Elsevier Ltd LIAG, Leibniz Institute for Applied Geophysics, Stilleweg 2, Hannover, 30655, Germany Carbon dioxide; Climate models; Continuous time systems; Gamma rays; Glacial geology; Lakes; Magnetic susceptibility; Magnetism; Moisture determination; Sediments; Tropics, %moisture; Authigenic; Authigenic urania; Cyclostratigraphy; Depth models; Milankovitch cycle; Palaeoclimatology; Quaternary; Spectral gamma rays; Tropical north america, Moisture, astronomy; borehole logging; interglacial; lacustrine deposit; lake level; magnetic susceptibility; moisture content; paleoclimate; Pleistocene; Postglacial; precession; reconstruction; uranium, Federal District [Mexico]; Lake Chalco; Mexico City; Mexico [North America] https://www.scopus.com/inward/record.uri?eid=2-s2.0-85138817916&doi=10.1016%2fj.quascirev.2022.107739&partnerID=40&md5=42779e5a48290b7909df06c828116dc1 cited By 0 M. Sardar Abadi C. Zeeden A. Ulfers T. Wonik article Chávez-Lara2022359 A sediment record from Lake Chalco, Basin of Mexico, revealed the presence of two endemic ostracod species during the latter part of Marine Isotope Stages (MIS) 6 (146–130 ka) and MIS5 (130–72 ka), namely Candona alchichica and Limnocytherina axalapasco. Higher abundance of C. alchichica was found during MIS6, when prevailing conditions were cold, lake waters were fresh, and relatively deep bottom waters were anoxic. The species is typically associated with saline environments today, consistent with its presence in MIS5 sediments. The Chalco record, however, reveals that it coexisted with freshwater diatom species during MIS6. Thus, we suggest that C. alchichica had a wider salinity tolerance, ranging from freshwater to more saline environments. Examination of MIS5 substages provides further insights into ostracod species responses to changing lake conditions. During MIS5e, the lake water level declined and salinity and dissolved oxygen in the water column increased, thereby favouring L. axalapasco productivity, whereas C. alchichica productivity decreased. Enhanced runoff and lower than average evaporation during MIS5d coincided with the increasing abundance of C. alchichica, suggesting a period of relatively high lake level and more dilute waters. These environmental conditions, however, changed during MIS5c when lake stage dropped once again and L. axalapasco abundance increased. Shallow conditions during this substage were optimal for L. axalapasco. Subsequently, as the lake level continued to decline during MIS5b, both ostracod species disappeared from the sediment record. Finally, during MIS5a, runoff increased and both ostracod species reappeared in the record, with L. axalapasco dominating, suggesting another period of lake level recovery. Increased evaporation rates during the last part of this substage (75–72 cal ka BP) may have led to disappearance of ostracods from the sediment record. Overall, during MIS5, we detected higher L. axalapasco, which represent relatively shallow lake conditions. © 2022, The Author(s), under exclusive licence to Springer Nature B.V. 2022 English 09212728 10.1007/s10933-022-00237-w Journal of Paleolimnology 67 Springer Science and Business Media B.V. 359-373 Instituto de Geología, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Mexico, 04510, Mexico; Instituto de Geofísica, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Mexico, 04510, Mexico; Posgrado en Ciencias de la Tierra, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Mexico, 04510, Mexico; Large Lakes Observatory &, Department of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN 55812, United States 4 dissolved oxygen; environmental conditions; lake level; lake water; marine isotope stage; ostracod; paleoecology; runoff; seawater, Lake Chalco; Mexico [North America]; Valley of Mexico https://www.scopus.com/inward/record.uri?eid=2-s2.0-85125750119&doi=10.1007%2fs10933-022-00237-w&partnerID=40&md5=55775fb1716c2acef5c2f08b878604a4 cited By 4 C.M. Chávez-Lara S. Lozano-García B. Ortega-Guerrero M. Caballero-Miranda D. Avendaño E.T. Brown article Lozano-García2022 A new detailed pollen record of the penultimate glacial–interglacial–glacial cycle corresponding to the late marine isotopic stages (MISs) 6–3 (146–35 ka ago) has been obtained from Lake Chalco, in the Basin of Mexico. This record provides an insight into vegetation dynamics and climate variability at the northern limit of the American tropics. The pollen record displays a high temporal resolution with a mean sampling interval of ∼230 years. The changes in plant composition were reconstructed by pollen analysis and differences in plant composition between distinct periods were established. The wettest cold stage, indicated by a combination of diverse open vegetation and mesophytic taxa correlates with the penultimate late glacial MIS 6 (146–130 ka), when Lake Chalco was a deep freshwater lake. The penultimate interglacial MIS 5e (126.5–123.6 ka) shows a dominance of Pinus forests, with tropical taxa suggesting warmer than present conditions; environmental proxies indicate drier conditions and that the lake transitioned into a saline water body. Open communities and Pinus and Quercus forests with mesophytic taxa and, during the stadial periods, MIS 5 d, 5c, and 5 b (125–90 ka), with tropical taxa, characterize the record of interstadials. Pinus-dominated forests characterize the landscape during MIS 5a. MIS 5c to MIS 3 showed lower and variable evenness and palynological richness, along with an increase in fire activity. During MIS 4 and 3, a trend towards drier conditions was also recorded with enhanced carbonate precipitation and proxies indicating saline conditions. Tree-line changes in response to climate change and taxa migration were documented. A comparison with long records from the Greenland ice cores, the marine Cariaco Basin and insolation parameters revealed that the pollen data and the Pinus pollen accumulation rates evidence the response of the vegetation to glacial and interglacial changes and to millennial-scale variability. Wetter conditions were inferred to exist during the Greenland interstadials, while drier conditions persisted during Heinrich events. © 2022 Elsevier Ltd 2022 English 02773791 10.1016/j.quascirev.2022.107830 Quaternary Science Reviews 297 Elsevier Ltd Universidad Nacional Autónoma de México, Instituto de Geología, Ciudad de México, 04510, Mexico; Universidad de Guadalajara, Centro Universitario de La Costa Sur, Jalisco48900, Mexico; Universidad Nacional Autónoma de México, Instituto de Geofísica, Ciudad de México, 04510, Mexico Forestry; Glacial geology; Lakes; Saline water; Tropics; Vegetation, Basin of mexico; Dry condition; Last glacial; Marine isotopic stages; Me-xico; Millennial-scale variability; Penultimate interglacial; Plant diversity; Pollen analysis; Vegetation dynamics, Climate change, climate change; climate variation; coniferous forest; glacial-interglacial cycle; Last Glacial; late glacial; marine isotope stage; Neotropical Region; palynology; reconstruction; vegetation dynamics; vegetation history, Arctic; Atlantic Ocean; Cariaco Basin; Caribbean Sea; Greenland; Lake Chalco; Mexico [North America]; Valley of Mexico https://www.scopus.com/inward/record.uri?eid=2-s2.0-85140807059&doi=10.1016%2fj.quascirev.2022.107830&partnerID=40&md5=f131b185af7806968c279ca3020e137e cited By 1 S. Lozano-García E. Torres-Rodríguez B. Figueroa-Rangel M. Caballero S. Sosa-Nájera B. Ortega-Guerrero C. Acosta-Noriega article Martínez-Abarca2021 The responses of lake productivity, vegetation, and fire events in the Basin of Mexico to orbital changes from late MIS 6 to MIS 3 (146–35 ka) have been studied based on geochemical (Ti, TIC, TOC, C/N), charcoal (CHAR) and pollen data of the sediment core CHA08 from Lake Chalco. The paleoenvironmental reconstruction identifies the MIS 6 as a wetter period with episodes of dry conditions, low forest cover and low fire activity. A sudden change from wetter to dry environments with low to high forest cover and fire activity episodes characterized the end of the MIS 6 (132–130 ka) coincident with high spring insolation. Variations in vegetation composition, with a tendency towards higher forest cover, fire-activity, runoff, and organic matter availability, are recorded during the MIS 5, MIS 4, and MIS 3. However, a reduction in the fire-activity was recorded for the cold and dry MIS 4. Spectral analysis based on the titanium concentration record of Lake Chalco suggests a precessional forcing on runoff variations. We explored the impact of the Intertropical Convergence Zone latitudinal migrations which have been related to the summer insolation at 65° N by comparing runoff data with other sedimentary records from North and Central America. Our results highlight the sensitivity of the high altitude tropical basin to climate variations. © 2021 Elsevier Ltd 2021 English 08959811 10.1016/j.jsames.2021.103231 Journal of South American Earth Sciences 109 Elsevier Ltd Instituto de Geología, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Ciudad de Mexico, CP 04510, Mexico; Instituto de Geofísica, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Ciudad de Mexico, CP 04510, Mexico; Large Lakes Observatory & Dept. of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN 55812, United States; Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Ciudad de Mexico, CP 04510, Mexico environmental change; fire history; glacial-interglacial cycle; paleoenvironment; palynology; reconstruction; vegetation dynamics, Lake Chalco; Mexico [North America] https://www.scopus.com/inward/record.uri?eid=2-s2.0-85102044799&doi=10.1016%2fj.jsames.2021.103231&partnerID=40&md5=c24a118b593709563e6502627abc786f cited By 11 L.R. Martínez-Abarca S. Lozano-García B. Ortega-Guerrero C.M. Chávez-Lara E. Torres-Rodríguez M. Caballero E.T. Brown S. Sosa-Nájera C. Acosta-Noriega V. Sandoval-Ibarra article Martínez-Abarca20212519 Lake Chalco lies south of the Basin of Mexico and has been the subject of studies related to Late Quaternary climate variability. In 2016, the International Continental Scientific Drilling Program “MexiDrill Project” recovered a 520-m sediment record from Lake Chalco. Magnetic susceptibility measurements revealed substantial changes in sediment physical properties between 343 and 285 m depth, suggesting changes in composition associated with fluctuations in the depositional environment. We targeted sediments in the 343–285 m interval for high-resolution facies analysis, to develop a model of Lake Chalco formation. We identified three facies associations, using sediment composition, texture, mineralogy and micro-morphological characteristics: (1) detrital facies, consisting of laminated silt, massive sand, stratified silty sand, clast-supported gravel and matrix-supported gravel; (2) biogenic facies, which include diatom ooze and bivalve coquina; and (3) volcaniclastic facies, represented by clast-supported pumice deposits. We propose that formation of Lake Chalco occurred in four stages, which we identified by changes in sediment characteristics. The first stage was an alluvial delta environment, in which debris and hyper-concentrated flows were the main sediment transport agents. The second was characterized by turbulent flows in a fluvial deltaic environment, which alternated with laminar flows associated with floodplains. The third stage was a time of fluvio-lacustrine transition in the basin, with formation of the previously identified Paleo-Chalco-I Lake, in response to wet conditions. During the fourth stage, a deep eutrophic lake formed (Paleo-Chalco-II), with an origin that appears to have been related to regional volcanism. Our working age-depth model indicates establishment of the lake at ca. 400 ± 46 ka. This paper presents the only available record of the transition from alluvial to lacustrine sedimentation of Lake Chalco. Our results allow us to establish (1) how the lake was formed and what the phases of its development were, (2) how a major volcanic event altered and transformed the lacustrine sedimentation, and (3) which climatic conditions dominated during the lake formation. The age for the onset of the lacustrine sedimentation in Chalco is for the first time constrained to around 400 ka. This enables to expand our knowledge of the climate for a time for which there is no information from terrestrial records of tropical North America. © 2021, Geologische Vereinigung e.V. (GV). 2021 English 14373254 10.1007/s00531-020-01964-z International Journal of Earth Sciences 110 Springer Science and Business Media Deutschland GmbH 2519-2539 Posgrado en Ciencias de La Tierra, Universidad Nacional Autónoma de México, Mexico City, CP. 04510, Mexico; Instituto de Geofísica, Universidad Nacional Autónoma de México, Mexico City, CP. 04510, Mexico; Instituto de Geología, Universidad Nacional Autónoma de México, Mexico City, CP. 04510, Mexico; Instituto Pirenaico de Ecología – CSIC, Apdo 13034, Zaragoza, 50080, Spain; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, United States; Large Lakes Observatory & Dept. of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN 55812, United States; School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom 7 climate conditions; climate variation; depositional environment; facies analysis; fluvial deposit; lacustrine deposit; Quaternary; sedimentation; stratigraphy; volcanism, Lake Chalco; Mexico [North America]; Valley of Mexico, Bacillariophyta; Bivalvia https://www.scopus.com/inward/record.uri?eid=2-s2.0-85099255072&doi=10.1007%2fs00531-020-01964-z&partnerID=40&md5=c4212c41d77b885c8ae5f3d9e52b327d cited By 5 R. Martínez-Abarca B. Ortega-Guerrero S. Lozano-García M. Caballero B. Valero-Garcés D. McGee E.T. Brown M. Stockhecke A.G.E. Hodgetts article Ortega-Guerrero2020 Sediments from Lake Chalco in central Mexico spanning from ca. 150 to 35 ka ago provide evidence of paleoclimatic variability in the North American tropics associated with the end of Marine Isotopic Stage (MIS) 6, the transition to the last interglacial (MIS 5.5, ca. 130-115 ka ago), and part of the last glacial (MIS 5.4 to early MIS 3, 115 to 35 ka ago). We applied a multiproxy approach based on the analysis of mineral magnetism, diatom assemblages and major elements geochemistry. The reconstructed paleoenvironmental history identify the end of the globally cool MIS 6 as wetter than present, with high lake level, and a subsequent change to drier climates at the onset of the last interglacial (ca. 130 ka). Large amplitude changes in most of the analyzed parameters from ca. 130 to 74 ka are approximately coincident with MIS 5 (130-71 ka). The amplitude of these changes decreases in MIS 4 (71-57 ka) and the early part of MIS 3 (57-35 ka). We proposed that the inferred climatic oscillations follow insolation variations during MIS 6 and part of MIS 5 (150-88 ka). Low summer and spring insolation and lower seasonality inhibited evaporation and favored high lake levels. Conversely, maxima in spring and summer insolation promoted dry conditions and low lake levels. The major wet-cold glacial and dry-warm interglacial relationship found in Lake Titicaca (Bolivia) and Lake Chalco records shows the sensitivity of high altitude tropical sites to climatic variability. © 2020 Elsevier Ltd 2020 English 02773791 10.1016/j.quascirev.2020.106163 Quaternary Science Reviews 230 Elsevier Ltd Universidad Nacional Autónoma de México, Instituto de Geofísica, Ciudad de México, 04150, Mexico; Universidad Nacional Autónoma de México, Posgrado en Ciencias de la Tierra, Ciudad de México, 04150, Mexico; Universidad Nacional Autónoma de México, Instituto de Geología, Ciudad de México, 04150, Mexico; University of Minnesota Duluth, Large Lakes Observatory and Department of Geological Sciences, Duluth, MN 55812, United States Glacial geology; Incident solar radiation; Magnetic properties; Magnetism; Minerals; Paleolimnology; Tropics, Climatic oscillations; Climatic variability; Interglacial(s); Magnetic mineralogy; Marine isotopic stages; Multiproxy approach; North America; Pleistocene, Lakes, interglacial; Last Glacial Maximum; Last Interglacial; magnetic property; marine isotope stage; mineralogy; paleoclimate; paleolimnology; Pleistocene; reconstruction; seasonal variation; seasonality, Bolivia; Lake Chalco; Lake Titicaca; Mexico [North America], Bacillariophyta https://www.scopus.com/inward/record.uri?eid=2-s2.0-85077947755&doi=10.1016%2fj.quascirev.2020.106163&partnerID=40&md5=72054372ef57a7a644474f59af867f5b cited By 12 B. Ortega-Guerrero D. Avendaño M. Caballero S. Lozano-García E.T. Brown A. Rodríguez B. García H. Barceinas A.M. Soler A. Albarrán article González-Flores2020 The shallow structures of the Chalco and Xochimilco sub-basins (southeastern Mexico Basin) are established based on a seismic line that stretches trough both depressions. Interpretation of the seismic line was constraint by the stratigraphic column cut by the approximately 3000 m deep Tulyehualco well. The seismic line was converted to depth based on a vertical transverse isotropy velocity model determined from the interval, and root mean square (rms) velocities of the geologic units as established at the Tulyehualco deep well. P-wave modelling confirmed the results. The volcano-sedimentary infill established is consistent with the stratigraphic column of the 502 m deep MexiDrill borehole. It was possible to establish 1) the base of the fine stratified lacustrine sediments, and 2) the top of the basalts along the Xochimilco and Chalco sub-basins. The Xochimilco and Chalco sub-basins are separated by a shallow structural high (interpreted as due volcanic flows) against which the lacustrine sediments abut. A conspicuous anticline shaped structural high (adjacent to Xico tuff ring) divides the Chalco sub-basin into two depressions. The top of the basaltic basement matches with the upper volcanic unit horizon. In the western trough, the basement gets deeper from east to west (from 336 m at the structural high, to 660 m to the west). Immediately east of the anticline-shaped structural high, the basement is located at 510 m. Beneath the Xochimilco trough (at 180 m approximately) the volcanic basement shallows up smoothly northwestwards. In the eastern part of the Xochimilco sub-basin, the shallow lacustrian sediments are relatively thin. Northwestwards of the Tulyehualco well, their thickness diminishes. This apparent thinning is accounted by the fact that there the seismic line occupies the northern rim of the depression. Reflections in the upper 300 m of the section are not continuous. Beneath the central part of Chalco lake the reflectors are horizontal with a slight westward dip. At both sides of this central zone, reflectors are inclined or have dome shapes. This indicates that deposition along the Chalco sub-basin has been deformed. The thickness of the reflections associated with the fine laminated to volcanoclastic material transition zone is approximately constant, but thins and finally abuts against the structural high. In the eastern trough, seismic reflections at the shallow first 300 m are not as fine as in the western trough. These low magnitude seismic reflections might be associated with coarse fluvial volcanoclastic material from nearby Popocatéptl volcano. Seismic amplification in these two tectonic depressions by numerical modelling of seismic wave propagation can be based on the structure here established. Between 8 and 9 high amplitude reflectors in the first 300 m of the infill sequence are interpreted as due to impedance contrasts between geological units. Density and velocity logs along the MexiDrill borehole support this interpretation. Shallow strata are approximately 30 m thick. Towards the basin base, the strata are thicker (70 m approximately). These thicknesses are consistent with the nature of the volcano-sedimentary infill cut by the MexiDrill borehole. In particular, each seismic reflection would represent a sedimentation cycle of approximately 30,000 years (corresponding to a mean thickness of 30 m). If a sedimentation rate of 0.8 mm per year holds along the first 200–300 m of the basin infill (i.e., neglecting compaction effects, etc.) then this upper sequence comprises a record of paleo-ambiental changes that affected the southern Mexico Basin during the last 250,000 to 375,000 years. © 2020 The Authors 2020 English 08959811 10.1016/j.jsames.2020.102722 Journal of South American Earth Sciences 103 Elsevier Ltd Posgrado en Ciencias de La Tierra, UNAM, Mexico City, Mexico; Instituto de Geofísica, UNAM, México City, Mexico; University of Texas at Austin Hildebrand Department of Petroleum and Geosystems Engineering, United States; Instituto Mexicano del Petróleo, Mexico City, Mexico; Petróleos Mexicanos Activo de Producción Samaria Luna Región Sur, Mexico City, Mexico basin analysis; data interpretation; P-wave; seismic data; stratigraphy; transverse isotropy; wave modeling; wave propagation, Chalco; Federal District [Mexico]; Mexico City; Mexico [Mexico (NTN)]; Mexico [North America]; Xochimilco https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087706490&doi=10.1016%2fj.jsames.2020.102722&partnerID=40&md5=55daab76caba58ee4e9895613c0fa01d cited By 0 E. González-Flores J.O. Campos-Enríquez R.V. Wong C. Torres-Verdín D.E. Rivera-Recillas E. Camacho-Ramírez article Cevallos-Ferriz2019193 A fragment of mummified wood collected from a Quaternary sedimentary sequence of Lake Chalco, Central Mexico, in the depocenter of the Basin (19°15'26"N, 98°58'32"W), has anatomical characteristics of Abies. Identification is based on the presence of a warty layer in the walls of the tracheids, prismatic crystals in ray cells, taxodioid pits in the cross-fields, and lack of ray tracheids and normal intercellular canals, among other well-preserved characteristics. This specimen represents the first macrofossil evidence of the genus in this region and suggests that by the late Quaternary it was already established in the surroundings of Lake Chalco, and most probably in what is now central Mexico. Unfortunately, as with morphological and genetic characteristics, the anatomical attributes of the wood of the genus have not been useful for the delimitation of species. Most wood characteristics have been considered of little diagnostic value. However, comparison of available anatomical descriptions of fossil and living species highlight differences among them, even with Abies religiosa wood, which is the closest species to Lake Chalco. Other characteristics or plant organs are needed to assemble a whole plant that can be used to establish phylogenetic relationships and clarify the evolutionary history of the genus. Meanwhile this wood is assigned to a new fossil taxon, Abies cuitlahuacii Cevallos-Ferriz, Ríos-Santos & Lozano-García. © Boletín de la Sociedad Geológica Mexicana 2019. 2019 English 14053322 10.18268/BSGM2019v71n1a10 Boletin de la Sociedad Geologica Mexicana 71 Instituto de Geología, Universidad Nacional Autónoma de México 193-206 Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Circuito de la Investigación Científica, Coyoacán CDMX, 04510, Mexico; Posgrado en Ciencias Biológicas, Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Circuito de la Investigación Científica, Coyoacán CDMX, 04510, Mexico 1 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85067013155&doi=10.18268%2fBSGM2019v71n1a10&partnerID=40&md5=405f531eeb1da4535ace3a8fbd1af4bc cited By 1 S.R.S. Cevallos-Ferriz C. Ríos-Santos S. Lozano-García article Caballero201962 Diatom-based transfer functions for salinity, precipitation and temperature were developed using a training set that included data from 40 sites along central Mexico. These transfer functions showed good performance parameters and were subsequently applied to the previously published diatom record from lake Chalco, southern Basin of Mexico. Heinrich stadials (HS-3 to HS-0) were reconstructed as cold and dry events, with HS-2 representing the coldest and driest conditions, while HS-1 shows a complex bimodal cooling pattern. Orbital scale variability is also recorded. High and variable lake salinities from ∼34 to 29 ka BP (marine isotope stage 3, MIS-3) corresponded with times of maximum summer insolation and evidences of frequent fires. MIS-2 was identified as a cold period, with low lake salinity associated with low evaporation, with two cold intervals during the minima in spring (∼25.5 ka BP) and summer (∼20 ka BP) insolation. The ∼20 ka BP cold event together with HS-2 (24-23 ka BP), defined a bimodal maximum cooling during the last glacial maximum (LGM: 24.5–19.5 ka BP) within the range of pollen-based estimates, further supporting a maximum tropical cooling of 4–5 °C for the LGM. The deglacial (19.5–11.5 ka BP) showed the highest precipitation anomalies with three peaks that closely correlated with glacier advances in the nearby mountains (Iztaccihuatl). The early Holocene marked a change towards high lake salinities and the highest positive temperature anomalies (+3.5 °C) during a peak in summer insolation. Even though at orbital scale Chalco showed a nearly opposite trend to the record from the more southerly lake Peten-Itza (Guatemala), at millennial scale it showed a common pattern of cold and dry conditions during HSs, comparable to other tropical latitude sites in the northern hemisphere and further supporting the idea that there is a strong coupling between tropical and higher latitudes climates, in particular with the North Atlantic. © 2018 Elsevier Ltd 2019 English 02773791 10.1016/j.quascirev.2018.12.002 Quaternary Science Reviews 205 Elsevier Ltd 62-75 Laboratorio de Paleolimnología, Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, Ciudad de México, CP 04510, Mexico; Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, Ciudad de México, CP 04510, Mexico Glacial geology; Incident solar radiation; Lakes; Paleolimnology; Tropics, Diatoms; Late Pleistocene; Micropaleontology; Monsoon; North America; Paleoclimatology, Transfer functions, climate variation; diatom; micropaleontology; monsoon; paleoclimate; paleolimnology; paleotemperature; Pleistocene; precipitation (climatology); quantitative analysis; salinity; transfer function, Atlantic Ocean; Atlantic Ocean (North); Guatemala [Central America]; Lake Peten Itza; Mexico [North America]; Peten; Valley of Mexico, Bacillariophyta https://www.scopus.com/inward/record.uri?eid=2-s2.0-85058506660&doi=10.1016%2fj.quascirev.2018.12.002&partnerID=40&md5=7503376714a91f5bb647f868343a1383 cited By 28 M. Caballero S. Lozano-García B. Ortega-Guerrero A. Correa-Metrio article Brown20191 The primary scientific objective of MexiDrill, the Basin of Mexico Drilling Program, is development of a continuous, high-resolution <span classCombining double low line"inline-formula ∼4400kyr lacustrine record of tropical North American environmental change. The field location, in the densely populated, water-stressed Mexico City region gives this record particular societal relevance. A detailed paleoclimate reconstruction from central Mexico will enhance our understanding of long-term natural climate variability in the North American tropics and its relationship with changes at higher latitudes. The site lies at the northern margin of the Intertropical Convergence Zone (ITCZ), where modern precipitation amounts are influenced by sea surface temperatures in the Pacific and Atlantic basins. During the Last Glacial Maximum (LGM), more winter precipitation at the site is hypothesized to have been a consequence of a southward displacement of the mid-latitude westerlies. It thus represents a key spatial node for understanding large-scale hydrological variability of tropical and subtropical North America and is at an altitude (2240 a.s.l.), typical of much of western North America. In addition, its sediments contain a rich record of pre-Holocene volcanic history; knowledge of the magnitude and frequency relationships of the area's explosive volcanic eruptions will improve capacity for risk assessment of future activity. Explosive eruption deposits will also be used to provide the backbone of a robust chronology necessary for full exploitation of the paleoclimate record. Here we report initial results from, and outreach activities of, the 2016 coring campaign. © Author(s) 2019. 2019 English 18168957 10.5194/sd-26-1-2019 Scientific Drilling 26 Copernicus GmbH 1-15 Large Lakes Observatory and Dept. of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN 55812, United States; Instituto de Geofísica, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico; Department of Earth and Planetary Science, University of New Mexico, Albuquerque, NM 87131, United States; Instituto de Geología, Universidad Nacional Autónoma de México, Mexico City, 04510, Mexico; Institut für Geosysteme und Bioindikation, Technische Universität Braunschweig, Braunschweig, 38106, Germany; Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford, OX1 3TG, United Kingdom; Instituto Pirenaico de Ecología, Agencia Consejo Superior de Investigaciones Científicas, Avda Montañana 1005, Zaragoza, 50059, Spain; School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, United Kingdom; Department of Geology and Environmental Science, University of Pittsburgh, Pittsburgh, PA 15260, United States; Leibniz-Institut für Angewandte Geophysik, Stilleweg 2, Hannover, 30655, Germany; LacCore and Continental Scientific Drilling Coordination Office, Department of Earth Sciences, University of Minnesota Twin Cities, Minneapolis, MN 55455, United States; Instituto de Geología, Universidad Nacional Autónoma de México, Cd. de México, 04510, Mexico; Instituto de Geofísica, Universidad Nacional Autónoma de México, Cd. de México, 04510, Mexico; Large Lakes Observatory and Dept of Earth and Environmental Sciences, University of Minnesota Duluth, Duluth, MN 55812, United States; Department of Geosciences, Pennsylvania State University, University Park, PA 16802, United States; Leibniz Institute of Applied Geophysics, Stilleweg 2, Hannover, 30655, Germany; Deutsches GeoForschungsZentrum, Helmholtz-Zentrum Potsdam, Geomikrobiologie, Potsdam, 14473, Germany; Department of Geosciences, University of Arizona, Tucson, AZ 85719, United States; Institut für Geo-und Umweltnaturwissenschaften, Albert-Ludwigs-Universität Freiburg, Freiburg, 79104, Germany; Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, United Kingdom Explosives; Infill drilling; Oceanography; Risk assessment; Surface waters; Volcanoes, Environmental change; Hydrological variability; Intertropical convergence zone; Natural climate variabilities; Paleoclimate reconstruction; Paleoclimate records; Scientific objectives; Sea surface temperature (SST), Tropics https://www.scopus.com/inward/record.uri?eid=2-s2.0-85076097631&doi=10.5194%2fsd-26-1-2019&partnerID=40&md5=868fbde0b595a248576347b1b13030a2 cited By 11 E.T. Brown M. Caballero E. Cabral Cano P.J. Fawcett S. Lozano-García B. Ortega L. Pérez A. Schwalb V. Smith B.A. Steinman M. Stockhecke B. Valero-Garcés S. Watt N.J. Wattrus J.P. Werne T. Wonik A.E. Myrbo A.J. Noren R. O'Grady D. Schnurrenberger R.M. Abarca A.O. Beltrán C. Caballero L. Cappio R. Cossio T. Ferland K. Hesse J. Kallmeyer D. Kumar S.G. Leon I. Martínez C.A. Noriega F. Preusser H. Rawson A.M. Soler S. Sosa-Nájera D.A. Villeda C. Zeeden article Friese2017200 Subsurface exploration relies on drilling. Normally drilling requires a drilling fluid that will infiltrate into the drill core. Drilling fluid contains non-indigenous materials and microbes from the surface, so its presence renders a sample unsuitable for microbiological and many other analyses. Because infiltration cannot be avoided, it is of paramount importance to assess the degree of contamination to identify uncontaminated samples for geomicrobiological investigations. To do this, usually a tracer is mixed into the drilling fluid. In past drilling operations a variety of tracers have been used, each has specific strengths and weaknesses. For microspheres the main problem was the high price, which limited their use to spot checks or drilling operations that require only small amounts of drilling fluid. Here, we present a modified microsphere tracer approach that uses an aqueous fluorescent pigment dispersion with a similar concentration of fluorescent particles as previously used microsphere tracers. However, it costs four orders of magnitude less, allowing for a more liberal use even in large operations. Its applicability for deep drilling campaigns was successfully tested during two drilling campaigns of the International Continental Drilling Program (ICDP) at Lake Towuti, Sulawesi, Indonesia, and Lake Chalco, Mexico. Quantification of the tracer requires only a fluorescence microscope or a flow cytometer. The latter allowing for high-resolution data to be obtained directly on-site within minutes and with minimal effort, decreasing sample processing times substantially relative to traditional tracer methods. This approach offers an inexpensive, rapid, but powerful alternative technique for contamination assessment during drilling campaigns. © 2017 Association for the Sciences of Limnology and Oceanography. 2017 English 15415856 10.1002/lom3.10159 Limnology and Oceanography: Methods 15 Wiley Blackwell 200-211 GFZ German Research Center For Geosciences, Section 5.3. Geomicrobiology, Potsdam, 14473, Germany; Department of Geoarchives, Laboratorio de Paleolimnologia, Instituto de Geofísica, UNAM, Mexico City, Mexico; Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, Indonesia 2 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85012942108&doi=10.1002%2flom3.10159&partnerID=40&md5=3510ecc7a8321f77eb30ea0e69c59c51 cited By 18 A. Friese J. Kallmeyer J.A. Kitte I.M. Martínez S. Bijaksana D. Wagner ICDP Lake Chalco Drilling Science Team Team article Lozano-García2017299 This paper presents a short description of the coring operations undertaken to recover the full lacustrine sedimentary sequence from Chalco. Geophysical techniques were used to determine the distribution and thickness of the sediments in order to select the drilling site. Resonance frequencies determined from H/V spectral ratios were used to determine an area where lake sediments reached 300 m thickness. Electromagnetic survey showed two changes in electric resistivity which were related to changes in sediment composition, the first from 100 to 120 m, related to an increase in volcanoclastic sediments and the second from 330 to 400 m related to the presence of a basaltic flows. Three wells were drilled with continuous recovery, reaching depths of 420 m in well A, 310 in B and 520 in C. Samples for geomicrobiological and metagenomics studies were collected during drilling operations. A total of 1152 m of core sediments were recovered reaching a maximum depth of 520 m. Recovery percentages were between 88 and 92 % in the three wells. Magnetic susceptibility analyses in the three sequences show that the first 260 m are mostly lake sediments, between 260 and 300 m sediments are coarser and below 300 m they are mostly volcaniclastic. Analysis of the sedimentary sequence of Lake Chalco that covers the last ~300000 years will allow documenting and extending the knowledge of climate variability in area, the paleoenvironmental history, basin closure history, lacustrian system development and volcanic activity recurrence. Studies of the physical properties of this sequence will be important for seismic propagation and basin structure modeling, and also will improve modeling of the subsidence process that this region experiences. 2017 English; Spanish 14053322 10.18268/BSGM2017v69n2a2 Boletin de la Sociedad Geologica Mexicana 69 Instituto de Geología, Universidad Nacional Autónoma de México 299-311 Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, C.P. 04510, Mexico; University of Minnesota, Large Lakes Observatory, Duluth, MN 55812, United States; Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, C.P. 04510, Mexico; University of Pittsburgh, Department of Geology and Environmental SciencePA 15260, United States; University of New Mexico, Department of Earth and Planetary SciencesNM 87131, United States; Institute of Geosystem and Bioindication, Technical University of Braunschweig, Braunschweig, 38106, Germany; Instituto Pirenaíco de Ecología, Avda. Montaña 1005, Zaragoza, 50059, Spain; CSDCO/LacCore, University of Minnesota MinneapolisMN 55455, United States; Departmento de Geofísica, Instituto Steinmann, Universidad de Bonn, Meckenheimer Allee 176, Bonn, Alemania, 53115, Germany; Grupo de Geofísica, Departmento de Gedesia y Geoinformation, Viena Universidad de Tecnología, Gußhausstr. 25-29, Viena, 1040, Austria; Leibniz-Institut für Angewandte Geophysik LIAG, Hannover, Germany; University of Birmingham, School of Geography, Earth and Environmental Sciences, United Kingdom 2 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85028953927&doi=10.18268%2fBSGM2017v69n2a2&partnerID=40&md5=1c258cef699f14fb8251fe9d04698bcb cited By 19 S. Lozano-García E.T. Brown B. Ortega M. Caballero J. Werne P.J. Fawcett A. Schwalb B.L. Valero-Garcés D. Schnurrenberger R. O'Grady M. Stockhecke B. Steinman E. Cabral-Cano C. Caballero S. Sosa-Nájera A.M. Soler L. Pérez A. Noren A. Myrbo M. Bücker N. Wattrus A. Arciniega T. Wonik S. Watt D. Kumar C. Acosta I. Martínez R. Cossio T. Ferland F. Vergara-Huerta article Bücker2017279 Paleolimnological studies require a broad understanding of the geometry and depth of the sedimentary fill of lake basins prior to coring campaigns. Seismic methods are routinely employed for the indirect characterization of lake-bottom sediments. However, the use of seismic methods might occasionally be limited due to surface conditions or poor seismic contrasts between the stratigraphic units, which lead to data quality that is too poor to provide sufficient information for the selection of drill sites. Sources of cultural noise are one of the main reasons why seismic methods fail in study areas near or within large cities, such as Mexico City. Under certain conditions, electrical and electromagnetic methods might be a suitable substitute or complement to seismic exploration, as they respond to different physical properties of the subsurface. To evaluate the applicability of such methods, here we present two recent case studies from the desiccated lakes Chalco and Xochimilco both located in urban areas within the Basin of Mexico where electrical resistivity tomography (ERT), transient electromagnetic (TEM) and magnetotelluric (MT) soundings were conducted for the characterization of lake basement and lacustrine sediments. In both examples, the results of the geophysical exploration contributed valuable stratigraphic information for the following drilling and core recovery, which highlights the potential of electrical and electromagnetic methods in paleolimnological studies. 2017 English 14053322 10.18268/BSGM2017v69n2a1 Boletin de la Sociedad Geologica Mexicana 69 Instituto de Geología, Universidad Nacional Autónoma de México 279-298 Fachbereich Geophysik, Steinmann-Institut, Universität Bonn, Meckenheimer Allee 176, Bonn, 53115, Germany; Forschungsgruppe Geophysik, Department für Geodäsie und Geoinformation, TU-Wien, Gußhausstr. 25-29, Wien, 1040, Austria; Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, C.P. 04510, Mexico; Instituto de Geofísica, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, C.P. 04510, Mexico; Departamento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, Ciudad de México, C.P. 04510, Mexico; Geotem Ingeniería S.A. de C.V., AlheliMz.7 Lt.13-A, Col. Ejidos San Pedro Mártir, Ciudad de México, C.P. 14640, Mexico; Large Lakes Observatory and Department of Earth and Environmental Sciences, University of Minnesota Duluth, 2205 E. 5th St., Research Laboratory Building 207, Duluth, MN 55812, United States; Department of Geology and Environmental Sciences, University of Pittsburgh, 505 SRCC, 4107 O'Hara Street, Pittsburgh, PA 15260, United States; Instituto Pirenaico de Ecología - CSIC, Avda. Montañana 1005, Zaragoza, 50059, Spain; Institut für Geosysteme und Bioindikation, Technische Universität Braunschweig, Langer Kamp 19c, Braunschweig, 38106, Germany; Fachbereich Geophysik, Steinmann-Institut, Universität Bonn, Meckenheimer Allee 176, Bonn, 53115, Germany; Departamento de Sismotectónica y Exploración Geofísica, Gerencia de Estudios de Ingeniería Civil, Comisión Federal de Electricidad, Augusto Rodin 265, Col. Noche Buena, Del. Benito Juarez, Ciudad de México, C.P. 03820, Mexico 2 https://www.scopus.com/inward/record.uri?eid=2-s2.0-85028992372&doi=10.18268%2fBSGM2017v69n2a1&partnerID=40&md5=ef8258cf71af43aa8248c9feaffa0fad cited By 9 M. Bücker S.L. García B.O. Guerrero M. Caballero L. Pérez L. Caballero C.P. Paz A. Sánchez-Galindo F.J. Villegas A.F. Orozco E. Brown J. Werne B.V. Garcés A. Schwalb A. Kemna E. Sánchez-Alvaro N. Launizar-Martínez A. Valverde-Placencia F. Garay-Jiménez