Skip to main content
Dryad

Data from: A unique Late Cretaceous fossil wood assemblage from Chilean Patagonia provides clues to high-latitude continental environment

Cite this dataset

Martínez, Leandro C. A. et al. (2023). Data from: A unique Late Cretaceous fossil wood assemblage from Chilean Patagonia provides clues to high-latitude continental environment [Dataset]. Dryad. https://doi.org/10.5061/dryad.kwh70rz9p

Abstract

Fossil plants, including large trunks, stems, some branches, and twigs, were collected from the Maastrichtian (68.9 Mya), upper Dorotea Formation in the Magallanes/Austral Basin, 16 km north of the Cerro Guido-Las Chinas complex in the southern Chilean Magallanes region. These fossil trunks range from 0.2 m to 2.2 m in length. Petrographic slides were made in three sections (transverse, radial, and tangential) and analysed under a light microscope to study the permineralised fossils. The woods and stems belong to Austroginkgoxylon gen. et sp. nov., Agathoxylon antarcticum, Podocarpoxylon paradoxi sp. nov., Podocarpoxylon mazzonii, Palmoxylon subantarcticae, and Nothomalvaceoxylon magallanense gen.et sp. nov. The growth rings of gymnosperms and anatomical characters of angiosperms were analysed to obtain palaeoecological data. Interactions between gymnosperm roots growing into the secondary xylem of an angiosperm (nurse logs) are recorded. The data obtained from the fossil woods suggest warm and humid conditions in this southern South American locality during the Late Cretaceous, providing a unique opportunity to study continental environments at high southern latitudes, which are poorly represented on a global scale.

README

DATA SET INCLUDE 7 (seven) files

  1. Coexistence Approach method.ods

  2. Mean Sensitivy.ods

  3. CSDM CURVE CPAP 7192.ods

  4. CSDM CURVE CPAP 7193.ods

  5. CSDM CURVE CPAP 7194.ods

  6. CSDM CURVE CPAP 7195.ods

  7. CSDM CURVE CPAP 7196.ods.

COEXISTENCE APPROACH METHOD

Author/Principal Investigator Information: Leandro C. A. Martnez
Co-Investigator Information: Juan Pablo Pino M.
Name: Juan Pablo Pino M.
ORCID: https://orcid.org/0000-0002-2092-023X.
Institution 1: Laboratorio de Paleoecologa, Facultad de Ciencias, Universidad de Chile.
Address 1: Las Palmeras 3425, uoa, Santiago, Chile.
Institution 2: Laboratorio de Paleobiologa de Antrtica y Patagonia, Instituto Antrtico Chileno.
Address 2: Lautaro Navarro 1245, Punta Arenas Chile
Email: juanpablo.pinomorales@gmail.com
Date of data collection: 2023-20-05
Geographic location of data collection: El Puesto. Las Chinass River Valley, Magallanes Region, Chile.
Information about funding sources that supported the collection of the data: The fossil woods and thin sections are stored in the Paleontological Collection of Antarctica and Patagonia of the Chilean Antarctic Institute (INACH) located in Punta Arenas, Magallanes Province, Chile.
File List: Coexistence Approach method.ods

Methodological information
Each tab corresponds to a single analyzed family (Araucariaceae, Podocarpaceae, Arecaceae, and Malvaceae), while all data are collectively analyzed and presented in the RESULTS tab.
In the data sheet for each analyzed family, MAT (Mean Annual Temperature), CMMT (Minimum Temperature of the Coldest Month), and MART (Temperature Annual Range) are expressed in °C. The empty cells in these datasets represent duplicated data, which was removed during the data curation process. In the RESULTS data sheet, the abbreviations correspond to the following plant families: ARAU (Araucariaceae), PODO (Podocarpaceae), ARECA (Arecaceae), and MALVA (Malvaceae). The variables MAX (maximum) and MIN (minimum) represent the climatic range for each Nearest Living Relative (NLR). The overlap or coexistence zone was calculated using the 90th (upper limit) and 10th (lower limit) percentiles of the climatic range for each NLR to ensure precise estimates.

See methods in:
GREENWOOD, D. R., ARCHIBALD, S. B., MATHEWES, R. W. and MOSS, P. T. 2005. Fossil biotas from the Okanagan Highlands, southern British Columbia, and northeastern Washington State: climates and ecosystems across an Eocene landscape. Canadian Journal of Earth Sciences, 42, 167185.
KERSHAW, A. P. 1997. A bioclimatic analysis of early to middle Miocene brown coal floras, Latrobe Valley, south-eastern Australia. Australian Journal of Botany, 45, 373387.
MOSBRUGGER, V. 1999. The nearest living relative method. In JONES, T. P. and ROWE, N. P. (eds.) Fossil Plants and Spores: Modern Techniques, The Geological Society, London, 261265 pp.
MOSBRUGGER, V. and UTESCHER, T. 1997. The coexistence approacha method for quantitative reconstructions of Tertiary terrestrial palaeoclimate data using plant fossils. Palaeogeography, Palaeoclimatology, Palaeoecology, 134, 6186.
REICHGELT, T., KENNEDY, E. M., MILDENHALL, D. C., CONRAN, J. G., GREENWOOD, D. R. and LEE, D. E. 2013. Quantitative palaeoclimate estimates for early Miocene southern New Zealand: evidence from Foulden Maar. Palaeogeography, Palaeoclimatology, Palaeoecology, 378, 3644.
THOMPSON, R., ANDERSON, K., PELLTIER, R., STRICKLAND, L., BARTLEIN, P. and SHAFER, S. L. 2012. Quantitative estimation of climatic parameters from vegetation data in North America by the mutual climatic range technique. Quaternary Science Reviews, 51, 1839.
UTESCHER, T., BRUCH, A. A., ERDEI, B., FRANOIS, L., IVANOV, D., JACQUES, F. M. B., KERN, A.K., LIU, Y.S., MOSBRUGGER, V. and SPICER, R. A. 2014. The Coexistence ApproachTheoretical background and practical considerations of using plant fossils for climate quantification. Palaeogeography, Palaeoclimatology, Palaeoecology, 410, 5873.
Software:
Libre Office. Version: 7.3.6.2 (x64) / LibreOffice Community
Past 4.03. Paleontological stadistics software for education and data analysis.

MEAN SENSITIVY

Author/Principal Investigator Information: Leandro C. A. Martnez
Name: Leandro C. A. Martnez
ORCID: https://orcid.org/0000-0003-3761-4869.
Institution: CONICET, Museo Histrico Regional, Gobierno de la provincia del Neuqun.
Address: Boulevard Nahuel Huapi 2177. Villa La Angostura (8407), Neuqun, Argentina.
Email: gesaghi@gmail.com
Date of data collection: 2016-20-02
Geographic location of data collection: El Puesto. Las Chinass River Valley, Magallanes Region, Chile.
Information about funding sources that supported the collection of the data: The fossil woods and thin sections are stored in the Paleontological Collection of Antarctica and Patagonia of the Chilean Antarctic Institute (INACH) located in Punta Arenas, Magallanes Province, Chile.
File List: 2. Mean Sensitivy.ods

Methodological information
Each tab corresponds to an analyzed specimen. In the data sheet, the column 'Rings' represents the number of growth rings, and the column 'µm' indicates their diameter in microns.

See methods in:
CREBER, G. T. 1977. Tree rings: a natural data-storage system. Biological Reviews, 52, 349383.
CREBER, G. T. and CHALONER, W. G. 1984. Influence of environmental factors on the wood structure of living and fossil trees. The Botanical Review, 50, 1448.
CREBER, G. T. and FRANCIS, J. E. 1999. Fossil tree-ring analysis: palaeodendrology. In JONES, T. P. and ROWE, N. P. (eds.) Fossil Plants and Spores: Modern Techniques, Geological Society, London, 245250 pp.
FRITTS, H. C. 1976. Tree Rings and Climate. Academic Press, London.
Software:
Libre Office. Version: 7.3.6.2 (x64) / LibreOffice Community

CUMULATIVE SUM DEVIATION FROM THE MEAN CURVES (CSDM)

Author/Principal Investigator Information: Leandro C. A. Martnez
Name: Leandro C. A. Martnez
ORCID: https://orcid.org/0000-0003-3761-4869.
Institution: CONICET, Museo Histrico Regional, Gobierno de la provincia del Neuqun.
Address: Boulevard Nahuel Huapi 2177. Villa La Angostura (8407), Neuqun, Argentina.
Email: gesaghi@gmail.com
Date of data collection: 2016-20-02
Geographic location of data collection: El Puesto. Las Chinass River Valley, Magallanes Region, Chile.
Information about funding sources that supported the collection of the data: The fossil woods and thin sections are stored in the Paleontological Collection of Antarctica and Patagonia of the Chilean Antarctic Institute (INACH) located in Punta Arenas, Magallanes Province, Chile.
File List: 2. CSDM CURVE CPAP 7192.ods, CSDM CURVE CPAP 7193.ods, CSDM CURVE CPAP 7194.ods, CSDM CURVE CPAP 7195.ods, and CSDM CURVE CPAP 7196.ods.

Methodological information
Each tab corresponds to a ring section of analyzed specimen. In the data sheet, the first column correspond to the number of cell in the ring, from earlywood to latewood. F1 to F5 correspond to the diameter in microns of a particular file of cells across of a particular ring.
Because a slightly different number of cells was present in each measured file, in order to create meaningful average plots data from the shorter sequences were stretched out by adding spaces into the spreadsheet so that data from the ring boundaries coincided exactly.

See methods in:
FALCON-LANG, H. J. 2000a. A method to distinguish between woods produced by evergreen and deciduous coniferopsids on the basis of growth ring anatomy: a new palaeoecological tool. Palaeontology, 43, 785793.
FALCON-LANG, H. J. 2000b. The relationship between leaf longevity and growth ring markedness in modern conifer woods and its implications for palaeoclimatic studies. Palaeogeography, Palaeoclimatology, Palaeoecology, 160, 317328.
Software:
Libre Office. Version: 7.3.6.2 (x64) / LibreOffice Community

Methods

The fossil woods described here are based on observations of 12 logs of silicified woods and stems collected from 16 km to the north of the Cerro Guido locality, Magallanes region, southern Chile (Fig. 1). Observations and descriptions of the slides were carried out with light microscopic (LM). Slides of the cross (CS), radial (RS), and tangential (TS) wood sections were prepared for observation using a Nikon light microscope. The terminology used follows, in general, the IAWA list of microscopic features (IAWA 2004, 1989). Cell dimensions are based on a minimum of 25 measurements, and the numbers in brackets indicate the minimum and maximum values. 

Two indices were used to quantify the intertracheary pitting:  the ‘Contiguity percentage index (Cp) and Seriation index (Si)’ of Pujana et al. (2016). Values of Si equal to or close to 1.00 indicate that all the intertracheary pits are uniseriate, while values of Si >1.00 indicate two or more seriate pits. Values of Cp equal to or close to 0% indicate that pits are non-contiguous, and values of Cp close to 100% indicate that all pits are contiguous.

Usage notes

Libre Office. Version: 7.3.6.2 (x64) / LibreOffice Community

Past 4.03. Paleontological stadistics software for education and data analysis.

Funding

Agencia Nacional de Investigación y Desarrollo, Award: 1151389

Agencia Nacional de Promoción Científica y Tecnológica, Argentina, Award: PICT-2019-03749