Exploring for the Future petrophysical testing program data release, NDI Carrara 1, Carrara Sub-basin, Australia

NDI Carrara 1 is a deep stratigraphic borehole that was drilled in 2020 under the MinEx CRC’s National Drilling Initiative (NDI) program in collaboration with Geoscience Australia and the Northern Territory Geological Survey. NDI Carrara 1 is the first stratigraphic test of the recently described Carrara Sub-basin, a Proterozoic aged depocentre located in the South Nicholson region of northwest Queensland and the Northern Territory. The borehole was drilled to a total depth of 1751 m and penetrated a succession of Cambrian aged Georgina Basin carbonate and siliciclastic rocks that unconformably overly a thick succession of Proterozoic age siliciclastic and carbonate-rich sediments. Although drilled on the western flank of the Carrara Sub-basin, NDI Carrara 1 did not penetrate to basement. Interpretation of the L210 deep-crustal seismic survey suggests that further Proterozoic sedimentary packages known from the northern Lawn Hill Platform in northwest Queensland are likely to be found underlying the succession intersected in NDI Carrara 1. The borehole was continuously cored from 283 m to total depth, and an extensive suite of wireline logs was acquired. Geoscience Australia and partners have undertaken an extensive analytical program to understand the depositional, structural, and diagenetic history of the sediments intersected in NDI Carrara 1. This program includes a targeted petrophysical study that aims to characterise the physical properties of these Proterozoic rocks through laboratory analysis of core samples, the results of which are summarised in this data release.This data release provides data from new X-ray Computerised Tomography (XCT) scanning and gas porosity and permeability testing for 32 samples from NDI Carrara 1. Additional low permeability tests were undertaken on select samples that were identified as being ultra-tight (permeability

NDI Carrara 1为一口深层地层钻孔，于2020年在MinEx CRC国家钻探计划（National Drilling Initiative，NDI）框架下，联合澳大利亚地质调查局（Geoscience Australia）与北领地地质调查局钻探完成。该钻孔是近年被报道的卡拉拉次盆地（Carrara Sub-basin）的首口地层勘探井；卡拉拉次盆地为一处元古宙（Proterozoic）沉积中心，位于昆士兰州西北部与北领地的南尼科尔森地区。该钻孔终孔深度达1751米，揭露了一套寒武纪乔治娜盆地（Georgina Basin）碳酸盐岩与硅质碎屑岩序列，该序列不整合覆盖于一套厚层元古宙富碳酸盐硅质碎屑沉积物序列之上。尽管钻孔布置在卡拉拉次盆地西翼，但并未钻遇基底。对L210深部地壳地震勘探（L210 deep-crustal seismic survey）的解译结果显示，在昆士兰州西北部劳恩希尔台地（Lawn Hill Platform）北部所识别的元古宙沉积地层组，大概率存在于NDI Carrara 1所揭露地层序列的下方。该钻孔自283米至终孔深度段实施了连续取芯，并获取了一套完整的测井曲线数据。澳大利亚地质调查局及其合作方已开展大规模分析计划，以解析NDI Carrara 1所揭露沉积物的沉积、构造与成岩演化历史。该计划包含一项针对性岩石物理研究（petrophysical study），旨在通过岩芯样品实验室分析表征这套元古宙岩石的物理性质，其研究成果总结于本数据集发布内容中。本数据集发布内容提供了NDI Carrara 1的32份样品的全新X射线计算机断层扫描（X-ray Computerised Tomography，XCT）数据与气体孔隙度、渗透率测试数据。并针对被鉴定为特低渗（ultra-tight）的筛选样品开展了额外的低渗透率测试（permeability