Paleohydrology of the Santiaguillo Basin (Mexico) since late last glacial and climate variation in southern part of western subtropical North America

Abstract

Stratigraphy, geochemistry and radiocarbon dating of a succession of sediment in the Santiaguillo Basin (central-northern Mexico) help reconstruct the millennial-scale dynamics of hydrological variability that occurred in the southern part of western subtropical North America since the late last glacial. Runoff was generally above average during the late last glacial from ~ 27 to 18 ka. Following this interval, runoff decreased and deposition of authigenic carbonate and aeolian transported sediment increased until ~ 4 ka. Heinrich 1 and 2, and Younger Dryas were intervals of reduced runoff and increased aeolian activity. The wetter climate of central-northern Mexico and arid conditions in north–northwestern Mexico during the late last glacial were probably related to formation of tropical cyclones in the eastern North Pacific during the autumn with restricted rainfall swaths and an absent/weaker North American Monsoon. Enhanced North American Monsoon and tropical cyclones with expanded rainfall swaths brought more summer and autumn precipitation to a broader region extending from the central-northern Mexico to the continental interiors of southwestern US during the early Holocene.

A 14‐ka Record of Dust Input and Phytoplankton Regime Changes in the Subtropical NE Pacific: Oceanic and Terrestrial Processes Linked by Teleconnections at Suborbital Scales

“…(i) During the deglaciation, between 14 and 11 ka, the region experienced discrete episodes of effective moisture during summer (at ~13, 12, and 11 ka) identified by discrete highstands of lake levels (Ortega et al, ), vegetation changes in the BCP (Rhode, ), alluvial fan deposits, and aggradation activity (Antinao et al, ; Spelz et al, ). (ii) During the early Holocene interval between ~11 and 7 ka, the region showed an increase in winter precipitation relative to the previous period with punctuated episodes of alluvial fan deposition (at ~ 10.5, 9.5, 9, and 8 ka; Antinao et al, ; Arriaga‐Ramírez & Cavazos, ), with overall wetter condition than today for most of the Sonora desert (Ortega‐Rosas et al, ; Roy et al, , ). (iii) The middle‐ to late‐Holocene over the last 7 ka shows the interruption of alluvial fan aggradations matching with desiccation of all lakes and the progressive drying of the BCP (Antinao et al, ; Arriaga‐Ramírez & Cavazos, ; Ortega et al, ; Ortega‐Rosas et al, ; Roy et al, , , ).…”

Orbital‐scale droughts in central‐northern Mexico during the late Quaternary and comparison with other subtropical and tropical records

“…However, sediments deposited during the drought of c. 13.5 ka are characterized by more calcite and less Ti/Ca compared with sediments representing the drought of c. 7 ka. In previous studies, Chávez‐Lara et al () and Roy et al () reconstructed runoff and water column salinity of the Santiaguillo lake between c. 27 and 4 ka. The new core is collected from a relatively central part of the lake, while both the previous studies are based on sediments from the modern shore.…”

“…In a regional synthesis of palaeoclimate records, Metcalfe et al () observed that the hydroclimate of the NAM region was affected by changes in the summer and autumn solar irradiances, location of ITCZ and ENSO variability. An earlier proxy‐based precipitation record representing the late last glacial–early Holocene from Santiaguillo showed first‐order positive correlation with the autumn insolation (Roy et al, ). We intended to identify possible climatic forcings on orbital‐scale drought dynamics of central‐northern Mexico and evaluated geographic coverage of the arid intervals that occurred only during the well‐constrained MIS 2 and MIS 1 (Fig.…”

“…(2015) and Roy et al (2015) reconstructed runoff and water column salinity of the Santiaguillo lake between c. 27 and 4 ka. The new core is collected from a relatively central part of the lake, while both the previous studies are based on sediments from the modern shore.…”

“…In a sedimentary record reaching up to the Marine Isotope Stage (MIS) 4, Roy et al () proposed that the winter storms had minimal influence in the regions located south of 29°N latitude during the last glacial period and the hydroclimate of northern Mexico was mainly influenced by the dynamics of the summer precipitation. During the LGM, precipitation was restricted to central‐northern Mexico, and a broader region in north‐northwestern Mexico remained dry (Roy et al, ). Northward expansion of the summer moisture during the deglaciation brought more humidity up to the Great Basin (Lyle et al, ).…”