Drill core from borehole taken in 1981 from the Nördlinger Ries. There are distinctive layers of light-coloured dolomite between fine-layered dark sediments of the former crater lake.
Photo: Gernot Arp, Göttingen University
15 million years before 'Creation Week', when creationists think Earth was magically created out of nothing, a meteorite struck in what is now southern Germany, just north of the Danube, creating a circular crater that filled with water to form a lake, in an area surrounded by the hills known as the Nördlinger Ries.
Now the sedimentary rocks formed on the lakebed are revealing their locked-up record of the geological and biological changes in the intervening 15 million years of Earth's 'pre-Creation' history.
They are also providing useful information about what any signs of life in Martian craters might look like.
First, a little AI information about Nördlinger Ries:
What information do you have on the Nördlinger Ries, in southern Germany and the associated meteor crater? The Nördlinger Ries is a large circular depression in southern Germany, located in the state of Bavaria. It is the result of a meteorite impact that occurred approximately 14.8 million years ago during the Miocene epoch. The impact formed a crater with a diameter of about 24 kilometers (15 miles), making it one of the best-preserved large impact structures on Earth.An analysis of dolomite in core samples has revealed an interesting sequence of events in the history of the lake that once filled the crater. A high proportion of the carbon isotope 13C is attributed to strong methane formation by microorganisms known as archaea in water with a low sulphate content. Earlier in its history, the core samples showed clear traces of high sulphate content and bacterial decomposition of sulphates. This changed shows that there were changes in the groundwater pathways and consequent mineralisation of the water in the lake as the crater floor cooled.
Here are some key points about the Nördlinger Ries and its associated meteor crater:The Nördlinger Ries serves as a valuable natural laboratory for scientists studying impact cratering processes and their implications for planetary geology. The study of impact structures like this one contributes to our understanding of Earth's geological history and provides insights into the broader processes that shape planetary surfaces.
- Formation: The Nördlinger Ries was formed when a large asteroid or comet collided with the Earth's surface. The impact caused significant geological and environmental changes in the region.
- Crater Characteristics: The impact crater is well-defined and has a distinct circular shape. Over time, the original crater has undergone various geological processes, and the central uplift structure has eroded, leaving a depression surrounded by a raised rim.
- Geological Features: The area around the Nördlinger Ries exhibits unique geological features, including suevite, which is a rock type formed from impact breccia. Suevite contains a mixture of shocked minerals and rock fragments that were fused together during the intense heat and pressure generated by the impact.
- Popigai Impact Structure: The Nördlinger Ries is often compared to the Popigai crater in Russia, as both are considered "double-layer" or "nested" impact structures. These types of structures result from complex impact events that involve the penetration of the Earth's crust and the formation of multiple rings of shattered rock.
- Impact Ejecta: The impact ejected material from the Nördlinger Ries is found in various locations, including distal deposits that extend beyond the immediate vicinity of the crater. Researchers study these ejecta layers to better understand the dynamics of the impact and its environmental consequences.
- Tourism and Research: The Nördlinger Ries has become a site of interest for both tourists and scientists. The distinctive landscape and geological features make it an attractive location for researchers studying impact cratering processes and the effects of such events on Earth's history.
The results of this analysis are published in the journal Geochimica et Cosmochimica Acta.
AbstractIn other words, when looking for signs of life in impact craters, it is important to allow for changes caused by geological changes in the underlying rocks and the source of water in any lake formed in the crater, and not attribute changes just to climate change.
In impact crater lakes, the lacustrine sedimentary records may not solely reflect climatic changes but also potential erosional effects from lithologically distinct impactite formations. The hydrochemical and biogeochemical processes during the deposition of the Nördlinger Ries impact crater lake, which fall in the range of the mid-Miocene Climate Transition, were studied by analysing microcrystalline authigenic carbonates in a drill core succession, using stable oxygen and carbon isotopes in conjunction with biomarkers. These investigations revealed an early sulfidic interval characterized by thiophenes, iso- and anteiso-C15:0 acids derived from sulfate reducing bacteria, and dolomites with low to intermediate δ13Ccarb values. The subsequent distinctive interval is characterized by extremely 13C-enriched dolomite (δ13Ccarb up to +20.93 ± 0.05‰ V-PDB), decline of iso- and anteiso-C15:0 acids and is rich in an Archaea-derived archaeol that is 13C-enriched (−14.7‰), indicating extensive methanogenesis in sulfate-depleted lake porewater during early diagenesis. The sulfate decline results from successive sulfate reduction when replenishment by sulfate-bearing inflow water is limited. The carbonates exhibit enriched 18O due to pronounced evaporation in a long-resided water body and enriched 13C by methanogenesis. A change in provenance of water derived from the sulfur-rich suevite (impact melt-bearing breccia) and crystalline source rocks to the sulfur-poor Bunte Breccia (continuous ejecta blanket) is required. Intermittently high Si/Al and Zr/Al at the high δ13C interval suggests sporadic short-term runoff increase, leading to fluctuating physiochemical lake conditions. A subsequent decline in both δ13Ccarb and archaeol indicates a decreasing lake level with intermittent subaerial exposure events, supported by bioturbation and mud cracks. The concomitant lake oxygenation is well supported by increasing Pr/Ph ratios and lipids derived from aerobic methanotrophs (13C-depleted 3-methyl-hopanoids). In the youngest unit, allochthonous lignites and biomarkers from lacustrine/soil sources appear, high total sulphur contents and thiophenes recur, and stable C and O isotope values decrease again. These observations suggest another major provenance change of the inflowing solutes, with increasing influx from weathered pyrite-bearing Jurassic claystones. These findings demonstrate that the climatic record expected from the stable carbon and oxygen isotopes of the Ries carbonates is strongly overprinted by hydrochemical and biogeochemical processes due to changing ion influx from substrate rocks, along the course of the successive ejecta erosion and catchment changes. Such an intrinsic control of lacustrine biogeochemical processes is also expected for other hydrologically closed impact crater lake basins, where catchment rocks with distinctively different lithologies are present.
Zeng, Lingqi; Gätjen, Jochen; Reinhardt, Manuel; Böttcher, Michael E.; Reimer, Andreas; Karius, Volker; Thiel, Volker; Arp, Gernot
Extremely 13C-enriched dolomite records interval of strong methanogenesis following a sulfate decline in the Miocene Ries impact crater lake
Geochimica et Cosmochimica Acta 362; 22-40. https://doi.org/10.1016/j.gca.2023.10.013
© 2023 Elsevier Ltd.
Reprinted under the terms of s60 of the Copyright, Designs and Patents Act 1988.
For creationists however, there is the trivial matter of these rocks containing a record of changes going back to 15 million years before they think Earth was magicked out of nothing. Creationism must be about the only belief system that staggers on regardless of how many facts disprove it. This illustrates the power of brainwashing and the ability of creationists to delude themselves into thinking all facts contradicting their claims are the product of lies, conspiracies, forgeries and tricks because they find it impossible to imagine that their ignorant intuition isn't the best available measure of reality, far surpassing anything science can produce.
The same fundamentalist cult also purports to believe that vanity and self-idolatry are sins.
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