Abstract Micropaleontology is crucial branch of Earth Sciences, with a pivotal role in the success of the oil and gas industry over the decades. This sector of paleontology is based on the taxonomical description of microfossils, which encompass fossils with size variation from 0.001 mm to 1 m. Normally these microorganisms have a high rate on preservation, thus they are widely accepted as reliable evidence to infer about paleodepositional settings and paleoclimate change. Furthermore, microfossils are critical to understanding the evolution through time, being many of them recognized as index fossil and providing useful biozones to correlation. Since 1950, microfossils have been taxonomically described mainly by stereomicroscopes. However, as the technology progress, traditional ways to study these organisms are challenged and improved by nondestructive three-dimensional imaging techniques, as X-ray tomographic microscopy (SRXTM), three-dimensional X-ray microscopy (3D-XRM), the X-ray computed microtomography (microCT) and X-ray computed nanotomography (nanoCT). Recently, one of the most compelling research areas in micropaleontology is the desire to automatize and enhance the details of systematic classification. Thereby, an increasing number of researches have applied the high-resolution X-ray analysis aiming to improve the morphological, taxonomic and taphonomic examination. Most of them have detailed the enhancement provided by the technique when compared with the standard microscopes, and raised questions about the traditional characters used on the microfossil systematic taxonomy. Nevertheless, even with the surpassing detail on microfossil characterization, the application of microCT has been hampered by the costs and sometimes by the needs of specific computer skill. Thus, this research has evaluated the use of microCT as the technique to classify a random bulk of microfossil (comprising foraminifers, ostracods, radiolarians, gastropods and echinoderms) with no further software treatment. No standard microscope analysis was performed. Despite chemical composition of microfossils, most of the specimens morphology, especially internal structures, have been easily acquired and analyzed. 96% of the microfossils of the dataset were identified at least on genus level. Irrespective of the deepness of detail, when considering the overall taxonomic identification, the microCT seems to be effective as the standard microscope. Nonetheless, when problematic specimens are evaluated, the microCT seems to be a more reliable and practical tool than other methods as Scanning Electron Microscopy. Thus, the technique can be used solo or as a complementary method to the stereomicroscope. Additionally, the high-resolution has the potential to lead to the expected automatized micropaleontology, since they can provide numerous images in several planes. This may create a strong database necessary to machine learning and computer identification.

中文翻译：

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在微化石鉴定中测试 X 射线计算机显微断层扫描：以巴西塞尔吉佩-阿拉戈斯盆地为例

摘要 微古生物学是地球科学的重要分支，几十年来在石油和天然气行业的成功中起着举足轻重的作用。古生物学的这一部分基于微化石的分类描述，其中包括大小变化从 0.001 毫米到 1 米的化石。通常这些微生物具有较高的保存率，因此它们被广泛认为是推断古沉积环境和古气候变化的可靠证据。此外，微化石对于理解随时间的进化至关重要，其中许多被认为是指标化石，并为相关性提供了有用的生物区。自 1950 年以来，微化石主要通过立体显微镜进行分类描述。然而，随着技术的进步，研究这些生物的传统方法受到无损三维成像技术的挑战和改进，如 X 射线断层显微术 (SRXTM)、三维 X 射线显微术 (3D-XRM)、X 射线计算机显微断层扫描 (microCT)和 X 射线计算机纳米断层扫描 (nanoCT)。最近，微古生物学中最引人注目的研究领域之一是自动化和增强系统分类细节的愿望。因此，越来越多的研究应用了高分辨率 X 射线分析，旨在改进形态学、分类学和土壤学检查。他们中的大多数都详细说明了与标准显微镜相比该技术提供的增强功能，并对微化石系统分类学中使用的传统特征提出了质疑。尽管如此，即使在微化石表征方面具有超凡的细节，microCT 的应用也受到成本的阻碍，有时还受到特定计算机技能需求的阻碍。因此，这项研究评估了使用 microCT 作为对随机大量微化石（包括有孔虫、介形动物、放射虫、腹足动物和棘皮动物）进行分类的技术，无需进一步的软件处理。没有进行标准显微镜分析。尽管微化石的化学成分不同，但大部分标本的形态，尤其是内部结构，很容易获得和分析。数据集中 96% 的微化石至少在属水平上得到鉴定。不管细节的深度如何，在考虑整体分类识别时，microCT 似乎是标准显微镜的有效工具。尽管如此，当评估有问题的标本时，显微 CT 似乎是比扫描电子显微镜等其他方法更可靠和实用的工具。因此，该技术可以单独使用或作为立体显微镜的补充方法。此外，高分辨率有可能导致预期的自动化微古生物学，因为它们可以在多个平面上提供大量图像。这可能会创建机器学习和计算机识别所需的强大数据库。因为它们可以在多个平面上提供大量图像。这可能会创建机器学习和计算机识别所需的强大数据库。因为它们可以在多个平面上提供大量图像。这可能会创建机器学习和计算机识别所需的强大数据库。