The volcanic emplacement and subsequent weathering of the Deccan Traps of India is believed to have had a significant influence in driving global climatic shifts from the Late Cretaceous and through the Cenozoic. The magnitude of the Deccan Traps' impact on Earth's surface environment is largely dependent on the speculated original footprint of the large igneous province. To test established estimates for the pre-erosive northern extent of the Deccan Traps, we applied low-temperature apatite (U-Th)/He thermochronology (AHe) on rocks from the Bundelkhand craton and overlying Proterozoic Vindhyan successions of central India ∼150–200 km northeast of the northernmost preservation of Deccan basalts. New AHe data reveal young ∼5–85 Ma AHe dates with low effective uranium concentrations (eU) between 5–22 ppm, with a steep positive date-eU correlation that plateaus at ∼350 Ma in grains with eU values >50 ppm. Inverse thermal history modeling—utilizing AHe diffusion parameters of the Radiation Damage Accumulation and Annealing Model (RDAAM)—indicate that observed AHe date-eU correlations are most consistent with thermal histories that require the craton and Vindhyan strata to be at or near surface temperatures by ∼66 Ma, followed by a discrete reheating event associated with Deccan volcanism. These results establish new minimal areal constraints for the northern extent of Deccan volcanism which thermally perturbed much of the Vindhyan succession. Thermal alteration of organic rich Vindhyan sediment may have provided an additional source of volatile emissions that facilitated late Maastrichtian warming at the onset of Deccan volcanism. New minimal northern constraints on Deccan volcanism additionally confirm that large volumes of Deccan basalts have been stripped away since the time of their emplacement, which poses considerable implications for unraveling their role in Cenozoic cooling.

印度德干圈闭的火山侵位和随后的风化被认为对推动从晚白垩世到新生代的全球气候变化产生了重大影响。德干圈闭对地球表面环境的影响程度在很大程度上取决于推测的大型火成岩省的原始足迹。为了检验对德干圈闭侵蚀前北部范围的既定估计，我们对来自邦德尔坎德克拉通和上覆的印度中部元古界温德岩层序的岩石应用低温磷灰石 (U-Th)/He 热年代学 (AHe)德干玄武岩保存最北端东北200公里。新的 AHe 数据显示年轻的~5-85 Ma AHe 日期具有 5-22 ppm 的低有效铀浓度 (eU)，具有陡峭的日期-eU 正相关性，在 eU 值 >50 ppm 的谷物中稳定在~350 Ma。逆热历史建模——利用辐射损伤累积和退火模型 (RDAAM) 的 AHe 扩散参数——表明观察到的 AHe 日期-eU 相关性与需要克拉通和 Vindhyan 地层处于或接近地表温度的热历史最一致∼66 Ma，随后是与德干火山活动相关的离散再加热事件。这些结果为德干火山活动的北部范围建立了新的最小区域限制，该火山活动对温德亚序列的大部分进行了热扰动。富含有机质的温迪安沉积物的热变可能提供了额外的挥发性排放源，促进了德干火山活动开始时马斯特里赫特晚期的变暖。