Geology

All clastic sediments are subject to compaction (and reduction of porosity) as the result of increasingly tighter packing of grains under a thickening overburden. Decompaction - the estimation of the decompacted thickness of a rock column - is an important part of subsidence (or geohistory) analysis. The following exercise is loosely based on the excellent basin analysis textbook by Allen & Allen (2013), especially their Appendix 56. Import stuff import numpy as np import matplotlib.pyplot as plt import functools from scipy.optimize import bisect %matplotlib inline %config InlineBackend.figure_format = 'svg' plt.rcParams['mathtext.fontset'] = 'cm' Posing the problem Given a sediment column of a certain lithology with its top at $y_1$ and its base at $y_2$, we are trying to find the thickness and average porosity of the same sediment column at a different depth (see figure below). We are going to set the new top $y_1’$ and work towards finding the new base $y_2’$. ...

Eustasy constitutes a key control on continental-shelf accommodation along with tectonism. The combined effect of these processes influences relative sea level, which is thought to regulate the locati…

Generating a realistic earth model that simultaneously fits data observed at multiple well locations has been a long-standing problem in petroleum geology. Two insights are offered for solving this pr…

Changes in sediment supply and caliber during the last ∼ 130 ka have resulted in a complex architectural evolution of the Y channel system on the western Niger Delta slope. This evolution consists of …

Generating a realistic earth model that simultaneously fits data observed at multiple well locations has been a long-standing problem in petroleum geology. Two insights are offered for solving this pr…

Although numerous case studies exist to illustrate the large-scale stratigraphic architecture of salt-withdrawal minibasins, there is no clear understanding of how stratal patterns emerge as a functio…