Strong-scattering medium can usually form a good sealing medium for oil and gas resources. However. conventional elastic full-waveform inversion (EFWI) methods are difficult to build reliable velocity models under the condition of lacking low-frequency information. The elastic direct envelope inversion (EDEI) method has been proven to be able to model large-scale Vp and Vs structures ... https://www.roneverhart.com/50-Pack-Red-Biodegradable-Balloons-12-Thickened-Extra-Strong-Eco-friendly-Latex-Helium-Party-Balloons/