Evidence of Sunspots From the Early Permian Forest Fires

Fossil forest reveals sunspot activity in the early Permian

Authors:

Luthardt et al

Abstract:

Modern-day periodic climate pattern variations related to solar activity are well known. High-resolution records such as varves, ice cores, and tree-ring sequences are commonly used for reconstructing climatic variations in the younger geological history. For the first time we apply dendrochronological methods to Paleozoic trees in order to recognize annual variations. Large woody tree trunks from the early Permian Fossil Forest of Chemnitz, southeast Germany, show a regular cyclicity in tree-ring formation. The mean ring curve reveals a 10.62 yr cyclicity, the duration of which is almost identical to the modern 11 yr solar cycle. Therefore, we speculate and further discuss that, like today, sunspot activity caused fluctuations of cosmic radiation input to the atmosphere, affecting cloud formation and annual rates of precipitation, which are reflected in the tree-ring archive. This is the earliest record of sunspot cyclicity and simultaneously demonstrates its long-term stable periodicity for at least 300 m.y.

Sakmarian Permian Chemnitz Petrified Forest was a wet Oasis in a Variable Semi Arid/Semi Humid Climate

Palaeoclimatic and site-specific conditions in the early Permian fossil forest of Chemnitz—Sedimentological, geochemical and palaeobotanical evidence

Authors:

Luthardt et al

Abstract:

As significant indicators of deep-time palaeoclimate, a number of new palaeontological, pedological and geochemical characteristics are provided for the Chemnitz Fossil Lagerstätte to depict more precisely its environmental conditions. For the first time, several lines of evidence indicate that this fossil forest, instantaneously preserved by volcanic deposits, once received an annual precipitation of around 800–1100 mm, but grew on a nearly unweathered palaeosol. Although the composition of this rich and diverse T0 assemblage suggests a hygrophilous, dense and multi-aged vegetation dominated by conservative lineages, the habitat was affected by environmental disturbances and pronounced seasonality. Repeated changes in local moisture availability are suggested by geochemical proxies, the co-occurrence to intergrowth of calcic and ferric glaebules in the palaeosol and developmental traits of perennial vegetational elements. Specific substrate adaptation is reflected by different root systems and cyclic growth interruptions recorded in the stems, branches and roots of long-lived woody plants. Many differentially adapted terrestrial animals complete the more comprehensive reconstruction of a late Sakmarian ecosystem and its climatic and preservational controls. Albeit spatially confined, this diverse in-situ record may contribute to understand wetland–dryland dynamics of sub-tropical Northern Hemisphere Pangaea.

An Exquisite Seed Fern From the Chemnitz Petrified Forest, Germany

Micro-CT investigation of a seed fern (probable medullosan) fertile pinna from the early Permian Petrified Forest in Chemnitz, Germany

Authors:

1. Zhuo Feng (a, b, c)
2. Ronny Röβler (b)
3. Volker Annacker (b)
4. Ji-Yuan Yang (a)

Affiliations:

a. Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China

b. DAStietz, Museum für Naturkunde, Moritzstraße 20, D-09111 Chemnitz, Germany

c. State Key laboratory of Palaeobiology and Stratigraphy (Nanjing Insitute of Geology and Palaeontology, CAS), Nanjing 210008, China

Abstract:

A new bipinnate fertile pinna, Sterzelitheca chemnitzensis, bearing alternate synangia, is described from the Chemnitz Petrified Forest, Germany. The specimen occurs in the basal volcanic ash of the Zeisigwald Tuff Horizon, Leukersdorf Formation, Lower Permian. Because it is partially embedded in the tuffaceous matrix, X-Ray micro-Computer Tomography was employed to investigate the complete morphology without mechanical preparation of the hand specimen. The pinna is 66 mm long and branched once at least, the ultimate pinnae alternately positioned on the penultimate axis at angles of 45-55°. Stalked synangia are bell-like, borne alternately on both the terminal portion of the penultimate axis and the ultimate axes at angles of 25-60°. The smooth walled stalk is 3-7 mm long, 1-1.5 mm wide. Individual synangia are up to 6.5 mm in diameter and 10 mm long, and bear 12-14 elongated sporangia. Tubular sporangia are thin walled, circular in transverse section, arranged at the rim of the circular synangial pad around a central hollow. The unique preservational mould of the studied specimen is neither a permineralisation nor a compression-impression. It is three-dimensionally preserved, but lacks any organic remains. We provide the first detailed three-dimensional features of a probable medullosan male reproductive organ from the Chemnitz Fossil Lagerstätte. The relatively simple structure of the specimen offers a better understanding of the Palaeozoic seed ferns.