Abstract Ancient human footprints have been known from Managua, Nicaragua, since the 1880s. The main footprint site, long preserved in the Acahualinca Tracks Museum ( Huellas de Acahualinca ), reveals hundreds of human footprints that represent a minimum of 12 clearly defined trackways and a trampled trail or path. Deer, opossum and bird tracks are also present at Acahualinca, and bison and tapir tracks have been documented from the nearby and stratigraphically equivalent El Recreo site. The age of the Acahualinca footprints is controversial, but the best current estimate is about 2–2.2 ka BP. The Acahualinca site is one of the most scientifically important human footprint sites known from the Holocene. It exhibits footprints that are very abundant, well-preserved, accessible for study and part of a large sample that demonstrates variation within a single population. The Acahualinca site has historical, cultural and archaeological importance in preserving at least two intervals of human occupation, that of the footprints and of the ceramics in much younger layers. Its significance to anthropology and palaeontology as a sub-fossil footprint locality is clear and the volcanological history of the area is intimately related to determining the age and the circumstances of footprint registration at Acahualinca. The Acahualinca footprints merit geoheritage status.

Abstract The Chortis Block of Central America is a cratonic-type peri-Gondwanan terrane and is commonly included in Neoproterozoic–Paleozoic palaeogeographical reconstructions. At present, most research has focused on the Mesozoic evolution of the Chortis Block, however, its earlier history remains poorly constrained. As a result, there is considerable debate surrounding the internal complexities of the Chortis Block and its tectonothermal evolution has not been well established by geochronological and geochemical data. New field investigations from the Nueva Segovia Schist (Northern Nicaragua), considered one of the oldest exposed parts of the Chortis Block, reveal it is composed primarily of deformed sequences of greenschist facies marine clastic and chemical sediments in conformable contact with felsic volcanics. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) detrital zircon data from two samples taken from the Nueva Segovia Schist reveal a youngest age peak of c. 250 Ma with other significant peaks at c. 500 Ma, c. 1.0 Ga and c. 1.2 Ga. Taken together with field observations, these data suggest the Nueva Segovia Schist was likely deposited between c. 250 and 110 Ma proximal to Amazonia during the Late Paleozoic, and they support a Precambrian age for the basement of the East Chortis Terrane. Taken together the data support a Pangaean position of the Chortis Block, adjacent to Amazonia inboard of Oaxaquia.

ABSTRACT A comprehensive correlation chart of Pennsylvanian–Eocene stratigraphic units in Mexico, adjoining parts of Arizona, New Mexico, south Texas, and Utah, as well as Guatemala, Belize, Honduras, and Colombia, summarizes existing published data regarding ages of sedimentary strata and some igneous rocks. These data incorporate new age interpretations derived from U-Pb detrital zircon maximum depositional ages and igneous dates that were not available as recently as 2000, and the chart complements previous compilations. Although the tectonic and sedimentary history of Mexico and Central America remains debated, we summarize the tectonosedimentary history in 10 genetic phases, developed primarily on the basis of stratigraphic evidence presented here from Mexico and summarized from published literature. These phases include: (1) Gondwanan continental-margin arc and closure of Rheic Ocean, ca. 344–280 Ma; (2) Permian–Triassic arc magmatism, ca. 273–245 Ma; (3) prerift thermal doming of Pangea and development of Pacific margin submarine fans, ca. 245–202 Ma; (4) Gulf of Mexico rifting and extensional Pacific margin continental arc, ca. 200–167 Ma; (5) salt deposition in the Gulf of Mexico basin, ca. 169–166? Ma; (6) widespread onshore extension and rifting, ca. 160–145 Ma; (7) arc and back-arc extension, and carbonate platform and basin development (ca. 145–116 Ma); (8) carbonate platform and basin development and oceanic-arc collision in Mexico, ca. 116–100 Ma; (9) early development of the Mexican orogen in Mexico and Sevier orogen in the western United States, ca. 100–78 Ma; and (10) late development of the Mexican orogen in Mexico and Laramide orogeny in the southwestern United States, ca. 77–48 Ma.