Access to the geochemical conditions of paleoenvironments is made through the analysis of the chemical composition of the hydroxyapatite of fossil bones. This is because the bones were able to incorporate chemical elements from adjacent fluids into their pores and channels during the fossildiagenesis process, and as a result, have their original apatite substituted. The main goal of the present study was to seek geochemical signatures in bones and related sedimentary rocks from three well-known fossiliferous units of the Paraná Basin in southern Brazil: Irati Formation, Cisuralian (three bones/rocks sampled); Rio do Rasto Formation, Guadalupian (three bones/rocks sampled) and Santa Maria Supersequence, Late Ladinian–Early Norian (nine bones/rocks sampled). Fossils and rocks were analyzed by ICP-MS. Although the Permian fossil and rock samples (from Irati + Rio do Rasto Formations) have variations among them, some geochemical parameters are common (high Be–Co–Cu–Zn–Y–W–Pb contents). This composition differentiates them from the Triassic fossils and rocks (from Santa Maria Supersequence - high contents of V–As–Ba). The P content (essential in apatite) was used to determine the degree of preservation of the studied material. The better-preserved Permian specimen has a mean = 434.19 ratio (P content of fossil bones/P content of rock) and the lowest ratio = 1.87. Within the Triassic specimens, the better preserved has ratio = 205.64 and lowest = 2.24. In Permian specimens, Y shares similar ionic radio with Ca. For Triassic specimens, Y replaces Ca and As either replaces P or is associated with minerals in bone cavities. So, Y and As substitute Ca in the analyzed material. Therefore, the Permian samples are better preserved than the Triassic ones based on their P contents; Y and As can be used as indicators to differentiate Permian fossils (high Y values) from Triassic ones (high As values). These geochemical signatures can help in forensic cases, such as robbery or illegal transport of fossils.

通过分析化石骨骼中羟基磷灰石的化学成分，可以进入古环境的地球化学条件。这是因为在化石成岩过程中，骨骼能够将相邻流体中的化学元素掺入其孔隙和通道中，从而替代了原来的磷灰石。本研究的主要目的是从巴西南部巴拉那盆地的三个著名的化石单元中寻找骨骼和相关沉积岩中的地球化学特征：Ciruralian的Irati组（取样的三个骨骼/岩石）；瓜达拉普安河的里约杜拉斯托组（取样了三个骨头/岩石）和拉丁裔－早诺里安晚期的圣玛丽亚超序列（取样了九个骨头/岩石）。化石和岩石通过ICP-MS分析。尽管二叠纪化石和岩石样品（来自Irati + Rio do Rasto地层）之间存在差异，但一些地球化学参数是常见的（Be-Co-Cu-Zn-Y-W-Pb含量高）。这种成分将它们与三叠纪化石和岩石区分开（与圣玛丽亚超序列-V–As–Ba含量高）不同。P含量（磷灰石中必需的）用于确定研究材料的保存程度。保存得更好的二叠纪标本的平均比为434.19（化石骨的P含量/岩石的P含量），最低的比值为1.87。在三叠纪标本中，保存得更好的比率为205.64，最低的比率为2.24。在二叠纪标本中，Y与Ca具有相似的离子辐射。对于三叠纪标本，Y替代Ca，而As替代P或与骨腔中的矿物质有关。所以，分析材料中的Y和As替代Ca。因此，基于它们的P含量，二叠纪样品比三叠纪样品保存得更好。Y和As可用作区分二叠纪化石（Y值高）和三叠纪化石（As值高）的指标。这些地球化学特征可以在法医案件中提供帮助，例如抢劫或非法运输化石。