Digging Deep into Ghana's Slavery History - Archeogeophysics Survey Project

The Digging Deep into Ghana’s Slavery History Project is a fully integrated multidisciplinary research program to systematically investigate sites associated with the slave trade in Ghana using state-of-the-art geophysical methods. The trans-Atlantic slave trade had devastating impacts on Africa. These slave relics and sites will provide crucial insights into slave trade routes and the living conditions of enslaved people. One of the sites investigated is the Fort at Tantumquery. The first archaeological and geophysical investigation of the Fort at Tantumquerry was conducted in September 2024. A team from the Department of Physics of the Kwame Nkrumah University of Science and Technology (KNUST) and the University of Ghana’s Department of Archaeology and Heritage Studies (DAHS), with a representative of the Ghana Museums and Monuments Board (GMMB), conducted excavations and geophysical prospections (Electrical Resistivity survey and Ground Penetrating Radar) of the ruinous site of the fort. Background The fort at Tantumquerry was constructed by the Royal African Company (RAC), an English Trading Company, in the 1720s as part of their expanding network of coastal fortifications. The fort’s strategic location enabled control over local trade routes. Historical records indicate that the fort functioned as both a military installation and a commercial hub, facilitating trade relationships with local communities while asserting British territorial claims. The fort is perched on the summit of a low hill, about 30 m above sea level, and about 250 m off the coast of Ekumfi Otuam. The fort at Tantumquery is in Otuam in the Ekumfi District of the Central Region of Ghana. Soils are predominantly sandy loam, grading to clay loam on upper slopes. The tropical climate is characterized by high humidity and distinct wet (April-October) and dry (November-March) seasons, with implications for seasonal variations in soil moisture, which can affect geophysical measurements. Data The workflow for the study involved site selection, unmanned aerial vehicle (UAV) photography, geophysical surveys, archaeological excavation and documentation of archaeological relics. Unmanned aerial vehicle photography was conducted with a DJI Mini 3 Pro system equipped with high-resolution imaging. Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR) were selected based on site conditions, including surface topography and the anticipated complexity of subsurface archaeological features. A multichannel resistivity system was used to collect apparent resistivity data, whereas a MALA GPR ProEx system was used to acquire GPR data. The data in this collection are processed images of GPR and ERT data, images for site description, artifacts, general images of the team working in the field. The collection has the following data: Geophysics Ground Penetrating Radar processed data Electrical Resistivity processed data Photos Drone shots of site Photographs of Architectural Features Photographs of artifacts General photos of the team working in the field and off-site《深挖加纳奴隶制历史项目》（The Digging Deep into Ghana’s Slavery History Project）是一套完全整合的多学科研究计划，旨在采用前沿地球物理方法，系统调查加纳境内与奴隶贸易相关的遗址。跨大西洋奴隶贸易对非洲造成了毁灭性影响。这些奴隶遗存与遗址将为揭示奴隶贸易路线以及被奴役群体的生存境况提供关键洞见。本次调查的遗址之一是坦坦姆奎里堡垒（Fort at Tantumquery）。2024年9月，针对坦坦姆奎里堡垒开展了首次考古与地球物理调查。由夸梅·恩克鲁玛科技大学（Kwame Nkrumah University of Science and Technology, KNUST）物理系团队、加纳大学考古与遗产研究系（Department of Archaeology and Heritage Studies, DAHS）团队，以及加纳博物馆与古迹委员会（Ghana Museums and Monuments Board, GMMB）的代表组成的联合队伍，对该堡垒的废墟遗址开展了考古发掘与地球物理勘探——包括电阻率法测量与探地雷达（Ground Penetrating Radar, GPR）探测。 背景 坦坦姆奎里堡垒由英国贸易公司皇家非洲公司（Royal African Company, RAC）于18世纪20年代修建，作为其不断扩张的海岸堡垒防御网络的组成部分。该堡垒凭借战略位置得以掌控当地贸易路线。历史记录显示，该堡垒兼具军事设施与商业枢纽双重功能，在与当地社区建立贸易关系的同时，也彰显了英国的领土主张。堡垒坐落于一座低矮山丘的顶部，海拔约30米，距离埃库姆菲·奥图阿姆（Ekumfi Otuam）海岸约250米。坦坦姆奎里堡垒位于加纳中部地区埃库姆菲区的奥图阿姆镇。该区域土壤以砂壤土为主，上坡区域逐渐过渡为黏壤土。当地属于热带气候，湿度较高，且存在分明的湿季（4月至10月）与干季（11月至3月），这会导致土壤湿度出现季节性变化，进而对地球物理测量结果产生影响。 数据 本研究的工作流程涵盖遗址遴选、无人机（unmanned aerial vehicle, UAV）摄影、地球物理勘探、考古发掘以及考古遗存建档。本次无人机摄影采用搭载高分辨率成像设备的DJI Mini 3 Pro系统完成。电阻率层析成像（Electrical Resistivity Tomography, ERT）与探地雷达（GPR）的选型基于遗址现场条件，包括地表地形与预期的地下考古遗存复杂性。研究采用多通道电阻率系统采集视电阻率数据，同时使用MALA GPR ProEx系统获取探地雷达数据。本数据集包含的内容为：探地雷达与电阻率层析成像的处理后图像、遗址场景描述照片、出土文物照片，以及野外与场外作业团队的全景照片。 本数据集包含以下数据类型： 地球物理数据 探地雷达处理后数据 电阻率层析成像处理后数据 影像资料 遗址无人机航拍影像 建筑特征照片 出土文物照片 作业团队野外与场外场景全景照片