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The article critiques the comments made by Landing et al. on their paper, emphasizing that their interpretation of Cambrian strata in the Caledonian Highlands is flawed and lacks scientific support. It also discusses the issues with forced lithostratigraphic frameworks, the inadequate correlation methods used by Landing et al., and the inaccuracies in their data and interpretations regarding the Cambrian geological record.

Readers will be led down a random path from continental dynamics to paleoclimate. A key to understanding continental dynamics is recognizing that differences in gravitational potential energy per unit area between high and low terrain govern much of large-scale continental deformation. Removal of mantle lithosphere, not just crustal thickening, plays a crucial, but difficult-to-test, role in changes in surface elevation. Although measuring past surface heights remains a challenge, indications of such processes suggest that surface uplift associated with such removal can affect relative plate motion. Climate change, from a warmer to cooler climate, and associated changes in erosion and sedimentation introduce further complications to determining past elevations. The phenomena that led to such cooling include a number of possibilities, but I favor the emergence of islands in the Maritime continent, which transformed the Pacific Ocean from one with a warm eastern tropical Pacific, as during El Niño events, to the present-day La Niña–like background state. Teleconnections from the eastern tropical Pacific to Canada affect the duration of summers and the potential of high-latitude ice to accumulate. Lateral gradients in gravitational potential energy per unit area (GPE), a force per unit length, govern large-scale continental dynamics. Removal of mantle lithosphere and thickening of crust raise GPE; knowledge of mean surface elevations provides a test of these processes. Climate change from a warmer to cooler climate and from one with less to more erosion can give the false impression of elevation change. Emergence of Indonesian islands, more rain over them, a stronger Walker Circulation, and cooler eastern Pacific may have led to ice ages. [ABSTRACT FROM AUTHOR]

Geological maps are powerful models for visualizing the complex distribution of rock types through space and time. However, the descriptive information that forms the basis for a preferred map interpretation is typically stored in geological map databases as unstructured text data that are difficult to use in practice. Herein we apply natural language processing (NLP) to geoscientific text data from Canada, the U.S., and Australia to address that knowledge gap. First, rock descriptions, geological ages, lithostratigraphic and lithodemic information, and other long-form text data are translated to numerical vectors, i.e., a word embedding, using a geoscience language model. Network analysis of word associations, nearest neighbors, and principal component analysis are then used to extract meaningful semantic relationships between rock types. We further demonstrate using simple Naive Bayes classifiers and the area under receiver operating characteristics plots (AUC) how word vectors can be used to: (1) predict the locations of "pegmatitic" (AUC = 0.962) and "alkalic" (AUC = 0.938) rocks; (2) predict mineral potential for Mississippi-Valley-type (AUC = 0.868) and clastic-dominated (AUC = 0.809) Zn-Pb deposits; and (3) search geoscientific text data for analogues of the giant Mount Isa clastic-dominated Zn-Pb deposit using the cosine similarities between word vectors. This form of semantic search is a promising NLP approach for assessing mineral potential with limited training data. Overall, the results highlight how geoscience language models and NLP can be used to extract new knowledge from unstructured text data and reduce the mineral exploration search space for critical raw materials. [ABSTRACT FROM AUTHOR]

The Marron Volcanics of South-Central British Columbia are host to a suite of zeolites and other minerals, the most significant of which are brewsterite-Sr and wakefieldite-(Ce). Tschernich ([28]) states that according to the nomenclature established by the IMA in Coombs et al. ([10]), and analysis information given to Tschernich in conversations with Wise, heulandite from "Yellow Lake" should be labeled heulandite-Ca. Tschernich ([26]) describes one exceptional vein 50 meters long and 0.5-2 cm wide in which one side was primarily covered with colorless brewsterite with calcite crystals and brown, acicular goethite; on the opposite side were grown proportionally equal amounts of "Sr-bearing heulandite", brewsterite, and calcite crystals. The Yellow Lake occurrence is the third recorded for the wakefieldite subgroup of minerals, after Wakefield, Quebec [wakefieldite-(Y)] and the Kusu mine, Democratic Republic of Congo [Pb-bearing wakefieldite-(Ce), formerly I kusuite i ]. [Extracted from the article]